Antimicrobial Lipids from Plants and Marine Organisms: Comparison
Please note this is a comparison between Version 1 by Eliana Alves and Version 2 by Vivi Li.

Medicinal plants and marine organisms are natural sources of many antimicrobial compounds. Plant components with antimicrobial activity include alkaloids, sulfur-containing compounds, diterpenes/terpenoids, fatty acids (FA), some carbohydrates, steroidal glycosides, and phenolic compounds. Both primary and secondary metabolites are “generally recognized as safe” (GRAS) substances and the chance of triggering antimicrobial resistance is low. The most studied antimicrobial compounds of marine origin are peptides and alkaloids, contrarily to lipids. However, lipids are ubiquitously distributed in the different marine phyla, being quite abundant in some of them. Besides, several lipid classes from marine organisms have been recognized by their biological activity with a high potential to discover new antimicrobial compounds.

  • fatty acid
  • lipid extract
  • lipidomics
  • macroalga
  • marine invertebrate
  • mechanism of action
  • microalga
  • minimum inhibitory concentration
  • monoacylglycerol
  • natural antimicrobial

1. Introduction

The consumption of antibiotics in the world population is alarming. In 2016, the top five World Health Organization (WHO)’s major antibiotic consuming countries were Brazil, Turkey, Iran, Russia, and France, by decreasing order [1]. In Brazil, more than 2000 metric tons of antibiotics were consumed annually, followed by ca. 1000 metric tons in Turkey and Iran [1].
Both misuse and overuse of antibiotics has led to the development of antimicrobial resistance (AMR) in microorganisms, which has been a global problem and a growing threat for many years. Antimicrobial resistant microbes are found in people, animals, food, and the environment (hospital or other health care facilities, water, soil and air). Because of AMR, several disease conditions are becoming harder to treat, as tuberculosis, pneumonia, blood poisoning, gonorrhea, and foodborne diseases [2]. AMR leads to higher medical costs, prolonged hospital stays, and increased mortality, causing an economic burden for health care systems. The major cause of AMR is mostly due to misuse of antibiotics.
A number of 700,000 deaths occur worldwide because of drug-resistant diseases [3]. Tuberculosis causes 1.8 million deaths per year, while multidrug-resistant (MDR) tuberculosis causes 250,000 deaths per year and is a global priority for research and development. Gram-negative bacteria can cause death in days because of the lack of treatment options. By 2050, it is foreseen that drug-resistant diseases could cause 10 million deaths each year [3]. In 2017, the WHO identified a priority list of highly antimicrobial-resistant pathogenic microorganisms, also known as superbugs, that have developed survival mechanisms to circumvent the action of last-line antimicrobials (isoniazid, rifampicin, fluoroquinolone, carbapenem, third-generation cephalosporin, or vancomycin) [4]. There are twelve bacteria that have critical and high priority for treatment discovery, besides Mycobacterium tuberculosis, the causing agent of tuberculosis, including the “ESKAPE” pathogens: Enterococcus faeciumStaphylococcus aureusKlebsiella pneumoniaeAcinetobacter baumanniiPseudomonas aeruginosa, and Enterobacteriaceae [5]. Superbugs cause 33,000 deaths each year, in Europe, by antibiotic-resistant bacterial infections. Italy is the European country with one-third of all cases (11,000 deaths in total), followed by France (more than 5500 deaths) and Germany (with 2300 deaths) [6][7][6,7].
The world now lives the so-called “post-antibiotic era.” The current guidelines and recommendations from the WHO claim for an interconnected action and national action plans in a multisectoral and sustained “One Health” approach. This is aimed to tackle AMR and achieve the United Nations’ Sustainable Development Goals for 2030 toward humans, food and feed, plants and crops, environment, terrestrial and aquatic animals [8].
According to a recent WHO’s report, there are 252 antimicrobial agents in preclinical pipeline, being developed to treat WHO’s priority pathogens, but at very early stages of development [9]. Even so, very few target the most critical resistant Gram-negative bacteria, thus, they will generate little benefit over existing treatments [9]. As such, it appears that the future will come up with an increased need for new compounds with antimicrobial activity and combined therapeutic strategies, which can be effective against superbugs and bring revenue to the pharmaceutical industry. At the same time, several alternative approaches to conventional antibiotics have been extensively studied, not only to be used in the clinical field but also in animal health, control insect pest, protect agricultural crops, improve food safety, and water disinfection. Developing strategies include antimicrobial peptides (AMP), phage therapy, photodynamic antimicrobial chemotherapy (PACT), nanoparticles, probiotics, lysins, antibodies, quorum sensing inhibitors, and immunotherapeutic agents [5][10][11][12][13][14][5,10,11,12,13,14]. Combination therapy or multi-target approaches are being developed to hinder antibiotic resistance or to sensitize microorganisms to antibiotic action [15]. Another strategy to overcome AMR is the combination of conventional antibiotics with other molecules, as natural products and/or antimicrobials from natural sources, as plants and marine organisms, to enhance the antimicrobial effect against a wide range of pathogens.
Medicinal plants and marine organisms are natural sources of many antimicrobial compounds [14][16][17][18][14,16,17,18]. Plant components with antimicrobial activity include alkaloids, sulfur-containing compounds, diterpenes/terpenoids [19], fatty acids (FA) [20][21][22][20,21,22], some carbohydrates [23], steroidal glycosides, and phenolic compounds [24]. Both primary and secondary metabolites are “generally recognized as safe” (GRAS) substances and the chance of triggering antimicrobial resistance is low [25]. Simultaneously, marine organisms, mainly slow-moving or sessile, have developed adaptive defense mechanisms to protect themselves against pathogenic microorganisms. In some cases, marine organisms maintain associations with microbiota, being bacterial symbionts responsible by the synthesis of antimicrobial molecules [26][27][26,27].

2. Antimicrobial Lipids from Plants

Over the evolution, higher plants have developed several resilience strategies that allow them to resist or escape external attacks (e.g., microorganisms, pathogens, and predators). Their innate immune system had to be equipped with highly complex mechanisms of resistance and survival. The defense mechanisms of plants are unique and consist of both physical barriers and production of secondary metabolites. Plant secondary metabolites are formed in particular biosynthetic pathways by means of substrate-specific enzymes. The precursors of these secondary metabolites stem from primary metabolites, such as amino acids, FA, sugars, or acetyl-CoA. Some of the secondary metabolites serve as constitutive chemical barriers against the microbial attack (phytoanticipins) while others serve as inducible antimicrobials (phytoalexins) [28][44]. Oxylipins are a large family of plants’ secondary metabolites derived from PUFA that make part of their immune system and play key roles as antimicrobial agents. They are formed through enzymatic or radical oxidation of FA 18:2 and 18:3, in order to protect plants against pests and pathogens [29][45]. The enzymatic biosynthesis of these molecules is triggered by an alpha-dioxygenase (DOX) and by lipoxygenases (LOX) [30][31][46,47] that lead to the formation of the different types of molecules, including hydroxy-, hydroperoxy-, divinyl-, oxo-, and keto-derivatives of FA. Oxylipins are formed during abiotic and biotic stresses [32][48]. They are plant signaling molecules that can induce cell death and have an effect on the growth of eukaryotic microbes [29][45]. A deeper knowledge on plant response to stresses at molecular, physiological and metabolic levels will allow the development of new plant-derived antimicrobial molecules for use in the clinical field and as biopesticides [32][48]. The search for novel antimicrobials has led to exploring also amide derivatives of FA because they are natural self-defense agents in plants. FA amides are bioactive lipids [33][49] formed by the amidation of long chain saturated and unsaturated FA (UFA) [34][50]. They have higher antimicrobial activity against yeasts and bacteria than unmodified FA [35][51]. Amide derivatives of FA possess a broad bioactivity against different pathologic conditions (bacterial and parasitic infections, cancer, inflammation, etc.,) and their mechanisms of action imply protein synthesis inhibition and membrane leakage [36][52]. Also, microorganisms inside healthy plant tissues are unique to explore novel bioactive compounds. The FA and their amides from plant’s endogenous microorganisms have been scarcely reported despite being bioactive in a variety of processes and should be more explored as new therapeutic agents [36][52]. Lipids represent up to 7% of the dry weight of the leaves of higher plants and are important constituents of cell membranes, chloroplasts, and mitochondria [37][53]. Besides their structural function as main constituents of cell membranes, they have functional roles in plants (intracellular mediators, extracellular signalers, inter-species communication, and plant defense) and also serve as energy reserves (namely in seeds during germination) [21]. Palmitic acid (16:0) is the major saturated FA in leaf lipids. On the other hand, chloroplast membranes can have up to 90% α-18:3 FA in some lamellae [21]. FA exist in plants mainly linked to more complex molecules, as acylglycerols, esterified to a glycerol backbone in the form of triacylglycerols, sterol esters, MAG and diacylglycerols, phospholipids, or glycolipids. Several lipid classes, besides FA and MAG, have been identified in a diverse group of higher plants and tested for their antimicrobial activity, as will be detailed in the next sub-sections. Figure 12 illustrates the chemical structures of the different lipid classes with antimicrobial activity isolated from natural sources.
Figure 12. Chemical structures of the different lipid classes isolated from natural sources with antimicrobial activity.

2.1. Extraction and Isolation of Plant Lipids

Studies that extract or isolate lipids from plants to test their antimicrobial activity are scarce (Table 1). The biomass used to extract lipids includes leaves, fruits, seeds, stems, rhizomes, shoots, stem barks, and heartwoods (Table 1). Lipid extraction from plants is usually carried out with organic solvents of different polarities (mainly n-hexane, CHCl3, CH2Cl2, EtOAc, EtOH, BuOH, MeOH, and their mixtures) (Table 1). Liquid/liquid extractions or Soxhlet extraction are commonly performed to obtain total lipid extracts [38][39][40][41][42][54,55,56,57,58]. Instead of analyzing one lipid class or one lipid molecule, some studies have analyzed the total lipid extracts that were obtained by sequential extraction.
Table 1. Plant potential antimicrobial lipids or lipid-rich extracts, their origin and extraction method grouped by botanic family.
Botanical Name Family Common Name Country of Collection Plant Part Extracting Solvent/Method Isolated Lipids or Lipid Mixtures Ref.
Sesuvium portulacastrum L. Aizoaceae Sea purslane India Leaves MeOH/benzene/sulfuric acid (200:100:10, v/v)
 summarizes the information about the antimicrobial properties, the tested organisms, and the antimicrobial assays for each marine invertebrates’ species listed in Table 5Figure 12 illustrates the chemical structure of the main lipid classes with antimicrobial properties from these natural sources.
Table 5. Marine invertebrate lipids or lipid-rich extracts with antimicrobial potential, their origin and extraction method.
Scientific Name Phylum

(Class)
Collection Site Extracting Solvent(s)/Method Isolated Lipids or Lipid Classes Compound Identification Methods Ref.
FAME
Acanthodendrilla sp.
Table 6. Antimicrobial activity of lipids or lipid-rich extracts from marine invertebrates.
Scientific Name Activity Tested (Micro)Organisms Antimicrobial Testing Method/Evaluation Reference Antimicrobial (Positive Control) MIC, Diameter of Inhibition Zone (IZ) or Other Ref.
Porifera (Demospongiae) Gokasho Bay, Tokyo, Japan MeOH. Aqueous residue extracted with Et2O and n-BuOH. Organic extract fractionated by SiO2 (MeOH/CHCl3), purified by ODS column and C18 RP HPLC[ Steroid sulfates43] 1
Acanthodendrilla sp. Antifungal Yeast: S. cerevisiae (A364A, STX338-2C, 14028g, GT160-45C)[60]
Disk diffusion method  H and 13C NMR [135] IZ (mm): 7–11[169]
[135][169] Blutaparon portulacoides (A. St.-Hil.) Mears Amaranthaceae Capotiraguá Brazil Porifera (Demospongiae)
Antibacterial

Antifungal
KundingarengkekeRoots

Island, Indonesia
G(+): S. aureus, B. subtilis

G(-):
EtOH

E. coli,

Yeast: C. albicans

Fungi: EtOH, acetone and MeOH. Crude extract partitioned between aqueous MeOH and hexane, EtOAc, and BuOH. Hexane extract fractionated on normal-phase SiO2 column (n-hexane/EtOAc, 7:3, v/v). Purification by semi-preparative HPLCAcyl steryl glycosides (sitosteryl 3-β-O-glucoside 6’-O-palmitate and stigmasteryl 3-β-O-glucoside 6’-O-palmitate)
[44][70]
Sesterterpenes

(Luffariellolide derivatives, Acantholides) Cladosporium herbarum1H and 13C NMR, ESI-MS, HR-EI-MS Disk diffusion method   IZ (mm)

S. aureus: 7–11

B. subtilis: 7–12

E. coli: 7–12

C. albicans: 9–10

C. herbarum: 10–20[136][190]
[136][190] Arthrocnemum indicum (Willd.) Moq., Salicornia brachiata Roxb., Suaeda maritima (L.) Dumort. and Suaeda monoica Forsk. Glasswort for Salicornia genus, herbaceous seepweed for  Agelas oroidesS. maritima, and South-Indian seepweed for S. monoica Porifera (Demospongiae)India Gökçeada, Northern Aegean Sea,

TurkeyShoots of A. indicum and S. brachiata, and leaves of S. maritima and S. monoica
MeOH, MeOH/CHCl3 (1:1, v/v) and CHCl3. Extract dissolved in MeOH/H2O (9:1, v/v) partitioned against n-hexane. n-hexane, CH3Cl and MeOH extracts fractionated on SiO2 (EtOAc (0 → 100%) in hexane). Sephadex LH20 and C18 flash column [FA 1H and 13C NMR, 1D and 2D NMR, GC-MS, ESI-MS 3H]-hypoxanthine incorporation assay, 96-well microtiter plates, inhibition of enzymatic activityDry MeOH/benzene/sulfuric acid (200:100:10, v/v) FAME Artemisinin, Benznidazole, Melarsoprol, Miltefosine, Podophyllotoxin, Triclosan IC50 (µg/mL)

Antibacterial

M. tuberculosis: 9.4–>50

E. coli: 0.07–>50[45][61]


[137][162] Alternanthera brasiliana
Antiprotozoal: 0.35–>30 [137][162] Brazilian joyweed Brazil Root, stem and leaves EtOH and EtOAc Linoleate oxylipins Caminus sphaeroconia Porifera (Demospongiae) Dominica MeOH extracts chromatographed on Sepahdex LH 20 (MeOH and EtOAc/MeOH/H2O 20:5:2). Purification by gradient on SiO2 (CH2Cl2 to CH2Cl[
Caminus sphaeroconia Antibacterial G(+): MRSA, Enterococcus (VRE)

G(-): E. coli
2/MeOH 9:1, v/v)46][65]
Glycolipid (Caminoside) 1H and 13C NMR, ESI-MS in vitro inhibition   MIC (µg/mL)

MRSA: 12[123][147]
Phoenix dactylifera L. Arecaceae Date palm India Seeds CHCl3 and acetone Sterol and triterpenes [47][66]
Asphodelus aestivus Brot. Asphodelaceae (formerly Liliaceae) Summer asphodel Turkey Seeds Petroleum ether with Soxhlet extractor FA (C4:0, 6:0, 8:0, 10:0, 16:0, 18:0, 21:0, 24:0, 14:1, 15:1, 18:1n9t, 20:1, 24:1, 18:2, 18:2n6t, 18:2n6c, 20:2n6, 20:3n3, 22:6n3, and others unidentified) [38][54]
Artemisia incisa Pamp. Asteraceae   Pakistan Roots MeOH and recovered after elution on a SiO2 column with CH2Cl
P. aeruginosa
 ATCC 17853, 
S. typhi
 laboratory strain
Disk diffusion method
Rifampicin P. aeruginosa (9 mm at 0.25 mg/mL), S. aureus (7 mm, 1 mg/mL), S. typhi (9 mm at 1 mg/mL), B. cereus (10.5 mm at 2 mg/mL) Steryl glycoside:

β-sitosterol 3-O-β-D-glucopyranoside
[58][69]
Azadirachta indica A. Juss Multidrug-resistant clinical isolates of S. aureusSalmonella enterica serovar typhi


VRE: 12

E. coli: > 100 [123][147] Dominica MeOH extract purified by Sephadex LH-20 (MeOH). Sephadex LH-20 (EtOAc/MeOH/H2O (20:5:2, v/v)) Glycolipid (Caminoside) 1
Antibacterial G(+): MRSA, Enterococcus (VRE)

G(-): Xanthomonas maltophilia

Plant pathogen: Pythium ultimum
H and 13C NMR, ESI-MS [138][176] Disk diffusion method   V. vulnificus: 8–12
MIC (µg/disk)

MRSA: 6.3–>100

VRE: 3.1–>100

X. maltophilia: 25–>100

P. ultimum: 25–>100
[138][176] Dysidea arenaria Porifera (Demospongiae) Hainan Island, South China Sea, China CHCl3-soluble portion was repartitioned between petroleum ether and 90% MeOH. MeOH extract on flash SiO2 column (ether/EtOAc gradient) Sesquiterpenoid

(Sesquiterpenoid hydroquinone)
1H and 13C-NMR, ESI-MS[83
Dysidea arenaria Antiviral] Virus: HIV-1[99]
[  139][184] PFA IC50 (µM) 16.4–239.7 [139][184] Codium amplivesiculatum Antibacterial G(+): S. aureus (ATCC BAA-42, resistant to methicillin, penicillin, ampicillin/sulbactam, oxacillin, cefalotine)

G(-): V. parahaemolyticus (17802)
Disk diffusion method   MIC (µg/mL)/IZ (mm)

S. aureus: 125/15, S. dysenteriaeE. coliVibrio choleraeK. pneumoniae, and P. aeruginosa
MIC determined by microbroth dilution method and antibacterial sensitivity of SQDG determined by disk diffusion method (CLSI protocol) Not mentioned MIC of 32 μg/mL for S. typhi and two isolates of S. dysenteriae; MIC of 64 μg/mL for three isolates of S. typhiE. coli and V. cholerae and 256 μg/mL for K. pneumoniae SQDG [59][71]


V. parahaemolyticus: >250/8 Azadirachta indica A. Juss Raillietina spp. (helminth parasite) Ultrastructural changes by scanning electron microscopy Praziquantel Anthelmintic activity of SQDG with 0.5 and 1 mg/mL, respectively: paralysis time of 1 h and 0.7 h; death time of 1.6 h and 0.9 h SQDG [60][72]
Carapa guianensis and Carapa vasquezii Phytopathogenic fungi: A. flavusA. niger, and F. oxysporum Fungal mycelial growth inhibition trials developed in 96-well microtiter plates adding 10 μL of conidia suspensions (2 × 105 conidia mL−1) and 90 μL yeast peptone dextrose. Inhibition of germination observed under light microscopy 20 mM hydrogen peroxide MIC (μg/mL): 125–250 of C. guianensis and 15.6–125 of C. vasquezii against the three phytopathogenic fungi FA, FAME, squalene, β-sitosterol [42][58]
Ficus lutea Vahl Mucor miehei and B. subtilis Disk diffusion method Nystatin IZ of 17 mm for M. miehei; of 16 mm for B. subtilis; and of 12 mm for C. albicans exposed to 40 μg of compound Glycosphingolipid [1-O-β-D-glucopyranosyl-(2S,3R,5E,12E)-2N-[(2′R)-hydroxyhexadecanoyl]-octadecasphinga-5,12-dienine] named lutaoside [61][76]
Ficus pandurata Hance Yeast: C. albicans ATCC 90028, C. glabrata ATCC 90030, C. krusei ATCC 6258, A. fumigatus ATCC 90906, MRSA ATCC 33591, Cryptococcus neoformans ATCC 90113, S. aureus ATCC 2921, E. coli ATCC 35218, K. pneumoniae ATCC 13883, P. aeruginosa ATCC 27853, and Mycobacterium intracellulare ATCC 23068); chloroquine sensitive (D6, Sierra Leone) and resistant (W2, Indochina) strains of Plasmodium falciparum; parasite: Leishmania donovani promastigotes Modified versions of the NCCLS methods Antibacterial agent and antifungal agents not mentioned; antimalarial agents: chloroquine and artemisinin; anti-leishmanial agents: pentamidine and amphotericin B No activity was observed for any compound Ceramides [panduramides A-D, and newbouldiamide] [62][75]
Kunzea ericoides (A. Rich) J. Thompson E. coli ATCC 25922 and S. aureus ATCC 25923 Broth microdilution method utilizing the redox dye resazurin Not mentioned 0.625–10 mg/mL for S. aureus and more than 10 mg/mL in E. coli Steryl esters, triacylglycerols, free FA, sterols and phospholipids [63][77]
Pentagonia gigantifolia Ducke C. albicans ATCC 90028 and fluconazole-resistant C. albicans strains MIC and MFC determined by using a modified version of the microdilution NCCLS methods; sphingolipid reversal assay Amphotericin B, fluconazole and flucytosine C. albicans ATCC 90028 (0.52 to 1.04 μg/mL) Acetylenic acids: 6-octadecynoic acid and 6-nonadecynoic acid [64][38]
Hedyotis pilulifera (Pit.) T.N. Ninh S. aureus NBRC 100910, B. subtilis NBRC 13719, M. smegmatis NBRC 13167 Microdilution method Ampicillin Oleanolic acid (MIC value of 2.5 μg/mL against M. smegmatis), rotungenic acid (MIC value of 2.5, 2.5, and 1.25 μg/mL against S. aureusB. subtilis, and M. smegmatis, respectively), rotundic acid (MIC value of 5 μg/mL against B. subtilis) Triterpenoids, steroids, FA, glycolipids, and a ceramide [65][83]
Withania somnifera (L.) Dunal, Euphorbia hirta L., Terminalia chebula Retz. E. coli MTCC 46, P. aeruginosa MTCC 1934), Proteus mirabilis MTCC 3310, Raoultella planticola MTCC 2271, Enterobacter aerogenes (now Klebsiella aerogenes) MTCC 2822, B. subtilis MTCC 121, S. aureus MTCC 3160 Disk diffusion method for antibiotic susceptibility testing. Broth microdilution method for determination of MIC values Streptomycin MIC: W. somnifera leaf (0.039 mg/mL on P. aeruginosa); T. chebula fruits and stems (0.039 mg/mL on E. coli) and T. chebula stems and fruits (0.039 mg/mL on S. aureus): MBC of 0.039 mg/mL of T. chebula bark on S. aureus Sterols fraction [66][67]
Kaempferia pandurata Roxb. (synonym of Boesenbergia rotunda (L.) Mansf.) and Senna alata (L.) Roxb. MRSA, extended spectrum beta-lactamase (ESBL), and carbapenemase-resistant Enterobacteriaceae (CRE) Broth microdilution method Tetracycline and vancomycin for MRSA, cefotaxime and meropenem for ESBL-producing bacteria and for CRE MIC: K. pandurata extract (256 μg/mL) and S. alata extract (512 μg/mL) against MRSA Sterols and triterpenoid [67][68]
Zygophyllum oxianum Boriss. S. aureus ATCC 29213 and B. subtilis ATCC 6059 Modified disk diffusion method Ampicillin, gentamicin sulfate, and nystatin MIC: 2-mg leaves and stems extract (8 mm in S. aureus and 6 mm in B. subtilis, weak antibacterial activity); 2 mg-BuOH extract of whole air-dried aerial organs extract (5 mm in B. subtilis, 4 mm in E. coli and 20 mm in C. maltosa, good antifungal activity) Total lipid extract from leaves, stems and aerial organs (hydrocarbons,

triterpenol and steryl esters, triacylglycerols, free FA, sterols, phospholipids)
[68][59]
Abbreviations: CLSI, Clinical and Laboratory Standards Institute (formerly NCCLS); CRE, carbapenemase-resistant Enterobacteriaceae; ESBL, extended-spectrum beta-lactamase; FA, fatty acid; FAME, fatty acid methyl ester; G(-), Gram-negative; G(+), Gram-positive; IC50, half maximal inhibitory concentration; IZ: inhibition zone; LC50, concentration (ppm) at which 50% of larvae showed mortality; LC90, concentration (ppm) at which 90% of larvae showed mortality; MBC, minimum bactericidal concentration; MFC, minimum fungicidal concentration; MIC, minimum inhibitory concentration; MIQ, minimum inhibition quantity; MRSA, methicillin-resistant Staphylococcus aureus; MSSA, methicillin-sensitive Staphylococcus aureus; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (tetrazolium dye); NCCLS, National Committee for Clinical Laboratory Standards; ppm, parts per million; SQDG, sulfoquinovosyldiacylglycerol.
The fractionation of the extracts has been usually carried out by column chromatography and the purification of the compounds can be achieved by semi-preparative HPLC.
Different analytical platforms have been used to identify and characterize the structure of lipids in plant extracts. Generally, in natural products research, several complementary methods are used, such as 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, gas chromatography (GC) coupled to a flame ionization detector (GC-FID) or to a mass spectrometer (GC-MS), as well as MS with electrospray ionization (ESI-MS). Liquid chromatography-MS (LC-MS) and LC-MS/MS has not been much used on antimicrobial plant lipids’ research, only for sphingolipids analysis [50][74] and for linoleate oxylipins’ structural characterization [46][65]. Besides these common techniques, two-dimensional NMR techniques (2-D NMR such as correlation spectroscopy-COSY, nuclear Overhauser effect spectroscopy-NOESY, heteronuclear single quantum coherence-HSQC, and heteronuclear multiple bond correlation-HMBC) have been used for the identification of artemceramide-D [48][73] and glyceroglycolipids [60][72]. Other methods are regularly used for the analysis of lipid extracts or their fractionation, such as TLC [41][58][50][63][57,69,74,77], column chromatography as mentioned above, or paper chromatography, but the information is very limited [58][69]. Analysis of FA is mostly performed by GC-FID or GC-MS, after derivatization. Total lipid extracts or lipid fractions are subjected to derivatization techniques using acid or alkaline hydrolysis or transmethylation to obtain FAME.
To identify and/or quantify mixtures of compounds, simpler techniques can be applied as biochemical assays using colorimetric tests, as for instance, for sterols’ and steryl glycosides’ identification and quantification [67][58][60][68,69,72]. The data obtained for compounds’ identification in these studies on antimicrobial plant lipids are normally compared with data reported in the literature, especially for spectroscopic data [60][65][72,83].

2.2. Susceptibility Testing, Inhibitory, and Microbicidal Activities of Plant Lipids

Several microbial strains were used in plant lipid studies, comprising Gram-positive bacteria, Gram-negative bacteria, acid-fast bacteria, yeasts, filamentous fungi, parasitic protozoa, and some MDR strains and/or hospital isolated strains, such as MRSA (Table 2).
The lowest MIC against S. aureus were observed for the mixture of lipid classes from the aerial parts of Hedyotis pilulifera (1.25 µg/mL) [65][83], the artemceramide-B from the roots of A. incisa (0.0313 mg/mL) [48][73], the linoleate oxylipins isolated from Alternanthera brasiliana (50 µg/mL) [46][65], and the FAME extracted from the shoots of Salicornia brachiata (60 µg/mL, the same MIC also verified for a MRSA strain) [45][61]. In the case of artemceramide-B, its high inhibitory potential against S. aureus was assigned to this polar lipid bearing four hydroxyl groups and an amide linkage between two long aliphatic chains [48][73]. In the case of the linoleate oxylipins from A. brasiliana plant tissues, five isolated oxylipins were also found to be synthesized by endophytic Bacillus strains isolated from this plant. So, it was speculated that the antimicrobial activity of the oxylipins from this plant could be derived from the endophytic bacteria, supposing an ecological crosstalk between this plant and its endogenous microbiome [46][65]. Also, the LC-MS/MS approach was crucial to identify these antimicrobial compounds both in the plants and in the bacteria, shedding some light on the plant–bacteria interplay [46][65].
The FA from the extract of Cassia tora’s leaves and stems exhibited MIC between 200 and 1000 μg/mL against MRSA [39][55]. The minimum bactericidal concentrations (MBC) against MRSA were determined on FAME from the leaves of Excoecaria agallocha (0.25 mg against S. aureus) [51][62], for MRSA the leaves of Sesuvium portulacastrum (1.0 mg/mL) [52][79], and the hexadecanoate methyl and hexadecanoic acid <n-> obtained from the stem bark of Scaphium macropodum (3.13 mg/mL against S. aureus) [57][82].
Other studies have tested the antimicrobial activity of lipids against other pathogenic microorganisms of great relevance for the clinical area and included in WHO’s guidelines, such as those of the “ESKAPE” group. The lipid extracts with greater inhibiting capacity over Escherichia coli were the FA and their derivatives from n-hexane and CHCl3 extracts of the heartwood of A. adianthifolia (1 µg) [52][79], and the acyl steryl glycosides obtained from roots of B. portulacoides (50 µg/mL) [44][70]. Also with low MIC values, the FAME extracted from the shoots of S. brachiata (0.5 mg/mL) [45][61] and the FAME and steroids from Trigonella foenum-graecum seeds (100 µg/mL) [54][63]. A MBC range between 1.0 and 2.0 mg/mL was verified for FAME extracts from the leaves of different plants [43][45][51][60,61,62].
Some lipid extracts were found to have low MIC against P. aeruginosa, as the FA and their derivatives obtained from the n-hexane and CHCl3 extracts of the heartwood of A. adianthifolia (50 µg) [52][79], FAME and steroids from fenugreek seeds (T. foenum-graecum, 100 µg/mL) [54][63], and the SQDG extracted from the neem leaves (A. indica, 128 µg/mL) [59][71]. MBC toward P. aeruginosa between 0.1 and 2.0 mg/mL were verified for the extracts of FAME from leaves of different plants [43][45][51][60,61,62], similarly to the findings for the E. coli strains.
For strains of Salmonella typhimurium, a high MIC value of 25 mg/mL was obtained from the stem bark extract of S. macropodum which contained four compounds including two FA (hexadecanoate methyl and hexadecanoic acid <n->) [57][82]. The SQDG extracted from the neem leaves showed antimicrobial activity against MDR strains of Salmonella typhi and Shigella dysenteriae, both with a MIC range between 32 and 64 µg/mL, and also against MDR strains of E. coli (64–128 µg/mL), P. aeruginosa (128 µg/mL), S. aureus (128–256 µg/mL), and K. pneumoniae (256 µg/mL) [59][71]. Also, identical MIC values (0.5 mg/mL) of FAME extracts [43][45][51][60,61,62] and FA [38][54] from different plants were observed against K. pneumoniae.
Studies with Mycobacterium sp. demonstrated antimicrobial activity of extracts of fenugreek seeds that contained a mixture of FAME and steroids, having a MIC of 100 µg/mL against M. tuberculosis [54][63]. Activity against Mycobacterium smegmatis was also verified by extracts containing hexadecanoate methyl and hexadecanoic acid <n-> FA from the stem bark of Malva nut, S. macropodum (3.13 mg/mL) and a MBC of 6.25 mg/mL [57][82]. Finally, the triterpenoids oleanolic acid and rotungenic acid were found to have activity against M. smegmatis with a MIC of 2.5 µg/mL and 1.25 µg/mL, respectively [65][83].
The fenugreek seed extracts from which conjugated linoleic acid methyl ester, saturated FAME, and steroids were identified, showed an inhibitory effect against Plasmodium falciparum with a MIC of 0.29 µg/mL [54][63].
The glycolipid SQDG isolated from neem has a broad-spectrum of activity against MDR bacterial strains [59][71] and anti-helminthic activity [60][72], which proves to be a promising natural antimicrobial agent. This class of compounds isolated from neem has demonstrated antiviral activity (herpes simplex viruses, HSV-1 and HSV-2) [59][71], significant DNA binding properties [69][84], and anti-leukemic activity [70][85]. However, it is difficult to isolate a single compound or a class of compounds from complex matrices as plants. In most studies, the antimicrobial effects may be due to a synergistic effect between several natural antimicrobial compounds, and not just to the referred lipids. As such, more studies must be done to understand which lipids can effectively be responsible by the inhibitory or microbicidal effect and the structure–activity relationship.

3. Antimicrobial Lipids from Marine Organisms

The most studied antimicrobial compounds of marine origin are peptides and alkaloids [71][72][73][86,87,88], contrarily to lipids. However, lipids are ubiquitously distributed in the different marine phyla, being quite abundant in some of them. Besides, several lipid classes from marine organisms have been recognized by their biological activity with a high potential to discover new antimicrobial compounds.

3.1. Marine Algae

Algal biomass is mainly composed by minerals, sugars, proteins, and lipids, that represent 1–15%, depending on the algal species and its habitat. Lipids found in the macroalgae from the three phyla, Rhodophyta, Chlorophyta, and Ochrophyta (Table 3), have demonstrated antimicrobial activity against Gram-positive and Gram-negative bacteria, yeasts, and fungi [74][75][76][77][78][29,89,90,91,92] (Table 4). Most of these antimicrobial lipids were isolated from Rhodophyta and Chlorophyta. While the former shows a high diversity of algal species as source of antimicrobial lipids, studies in Chlorophyta were focused on species belonging to the order Bryopsidales.
Table 3. Algae lipids and lipid-rich extracts with antimicrobial potential, their origin and extraction method.
Scientific Name Collection Site Extracting Solvent(s)/Method Isolated Lipids or Lipid Classes Methods for Compounds Identification Ref.
Table 4. Antimicrobial activity of algae lipids or algae lipid-rich extracts.
Scientific Name Antimicrobial Activity Tested Microorganisms Antimicrobial Testing Method/Evaluation Reference Antimicrobial (Positive Control) MIC, MBC, Diameter of Inhibition Zone (IZ, in mm) or Other Ref.
Macroalgae–Chlorophyta
Macroalgae–Chlorophyta
Caulerpa racemosa Qionghai, Hainan, China EtOH (95%). Extract partitioned with EtOAc and n-BuOH SQDG [2S-1,2-di-O-palmitoyl-3-O-(6’sulfo-α-D-quinovopyranosyl) glycerol] 1H and 
Caulerpa racemosa Antiviral13 Viruses: Cox B3, HSVC NMR, ESI-MS [79][95]
Cytopathic effect (CPE) reduction assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method Acyclovir (HSV), Ribavirin (Cox B3) IC50/CC50 (µg/mL)/SI

Cox B3: 31.3/500/16

HSV: 7.9/250
[79][95] Caulerpa racemosa, Caulerpa lentillifera Port Dickson, Malaysia CHCl3, MeOH PUFA, MUFA, Terpenoids LC-MS
Caulerpa racemosa, Caulerpa lentillifera Antibacterial G(+):MRSA (MTCC 381123)

G(-): E. coli K1 (MTCC 710859)
Disk diffusion method, crude extracts (CHCl3 and MeOH)[80][96]
Penicillin-streptomycin PI: 97.7% (C. racemosa) [80][96] Caulerpa racemosa, Ulva fasciata Buzios, Rio de Janeiro, Brazil Acetone insoluble material extracted with CHCl3/MeOH (2:1 and 1:2, v/v
Caulerpa racemosa, Ulva fasciata). Lipid extract partitioned on SiO2 Antiviral column, eluted with CHCl3, acetone or MeOH Glycolipid-rich extracts (Sulfoglycolipids, Glycosyldiacylglycerols) HPTLC [81][97]
Viruses: HSV-1-ACVs, HSV-1-ACVr Titer reduction     [81][97] Caulerpa spp., Chlorodesmis fastigiata, Halimeda spp., Penicillus capitatus, Penicillus dumentosus, Penicillus pyriformis, Rhipocephalus phoenix, Udotea argentea, Udotea cyathiformis, Udotea flabellum, Udotea petiolata Bahamas, Florida Keys, Puerto Rico, Belize, Guan, Hawaii, Australia, Mediterranean Sea
Caulerpa spp., Chlorodesmis fastigiata, Halimeda spp.CH2Cl2. Chlorophylls removed with MgO3Si. Fractionation with SiO2 column and purification by HPLC Sequiterpenoids, Diterpenoids TLC, NMR, HPLC , Penicillus capitatus, Penicillus dumentosus, Penicillus pyriformis, Rhipocephalus phoenix, Udotea argentea, Udotea cyathiformis, Udotea flabellum, Udotea petiolata Antibacterial, Antifungal G(-):Serratia marinoruba, Vibrio splendida, V. harveyi, V. leiognathi, Vibrio sp.

Undescribed bacteria: VJP Cal8101, VJP Cal8102, VJP Cal8103

Fungi: Leptosphaeria sp. Lulworthia sp., Alternaria sp., Dreschleria haloides, Lindra thallasiae,

Undescribed fungi: VJP Cal8104, VJP Cal8105[82][98]
Plate assay-disk method   IZ (mm) > 2 [82][98] Chaetomorpha linum IMTA, Mar Piccolo of Taranto, Italy CHCl3/MeOH (2:1, v/v), Soxhlet extractor, EtOH (95%) Lipid extracts 1H and 
Chaetomorpha linum Antibacterial G(+): Pseudomonas sp., Staphylococcus sp., Streptococcus agalactiaeEnterococcus sp.

G(-): 
13C NMR, 1D and 2D NMR, GC-FID, TLC Vibrio alginolyticus, V. harveyi, V. mediterranei, V. ordalii, V. parahaemolyticus, V. salmonicida, V. vulnificus[83][99]
Codium amplivesiculatum
DysideaBahía Magdalena, Mexico  sp.CH2Cl2 Porifera (Demospongiae)/EtOH (97:3, v/[ Lakshadweep Islands, Kerala, India
Dysidea sp.v). Liquid/liquid extraction CH2Cl2/H2O. Fractionation with CH2Cl2. Crystallization in hot MeOH Fraction with clerosterol as main constituent. Isolated clerosterol did not show activity EtOAc and MeOH. EtOAc extract chromatographed on Sephadex LH20 (MeOH/CHCl31H NMR, IR , 1:1, v/v), SiO2 (2% EtOAc petroleum ether)[84] Sesterterpenes

(Sesterterpene sulfates)[100]
84 Antibacterial G(+): S. aureus, B. subtilis, M. luteus

1H and 13C NMR, HR-FAB-MS][100]
G(-): P. vulgaris, S. typhimurium, E. coli[140 Broth macrodilution method] Linezolid[183] MIC (µg/mL) 0.117–>15 [140][183] Ulva fasciata Malvan, India EtOH, fractionated by neutral alumina column with EtOAc/MeOH Sphingosine (major component: N-palmitoyl-2-amino-1,3,4,5-tetrahydroxyoctadecane) 1H and 13C NMR, FAB-MS, IR [85] Ulva fasciata[ Antiviral Virus: Semeliki Forest Virus (SFV)101  ]
Erylus lendenfeldi Porifera (Demospongiae) Malvan, India EtOH (90%). Extract fractionated. n-hexane fraction chromatographed on SiO2 and flash SiO2 Ceramide (Erythro-sphinga-4,8-dienine-N-palmitate) 1H and 13C NMR, ESI-MS, GC-MS, IR [86][102]
Mediterranean Sea, Egypt CHCl3/MeOH (2:1, v/v). Glycolipid separation using acetone on SiO2 column Glycolipid-rich extracts (DGDG) Mediterranean Sea, Egypt MeOH/CHCl3 (2:1, v/v). Sulfolipid isolation: diethylaminoethyl-cellulose column eluted with CHCl3/MeOH (6:4, v/v) and NH3 Sulfolipids (SQDG) GC-MS, GC-FID, LC-MS/MS, IR [75][89]
Ulva rigida Cap Zebib and Ghar El Melh, Tunisia CH2Cl2 and CH2Cl2/MeOH (1:1, v/v). Extracts fractionated on SiO2 column and TLC with n-hexane/EtOAc/CH2Cl2/MeOH FA 1H and 13C NMR, GC [27]
Macroalgae–Rhodophyta
Chondria armata Goa, West coast of India; Mumbai, India MeOH and CHCl3, Polar fractions: petroleum ether/EtOAc (1:1, v/v), MeOH/CHCl3 (2:98, v/v), MeOH/CHCl3 (5:95, v/v) Neutral glycolipids [main compound MGDG(20:5/16:0)] 1H and 13C NMR, ESI-MS/MS [88][104]
Chondrus crispus, Gracilaria vermiculophylla, Porphyra dioica IMTA and Portuguese coast, Portugal EtOAc in Soxhlet extractor FA GC-FID [89][105]
Falkenbergia

(heteromorphic sporophyte of Asparagopsis taxiformis)
Kollam coast, India MeOH. Fractionation on SiO2 column (petroleum ether/EtOAc and EtOAc/MeOH). Purification with TLC and RP HPLC FA GC-MS [90][106]


Yeast: C. albicans,

Candida famata, C. glabrata
Disk diffusion method   GC-FID, LC-MS/MS [87][103]
Galaxaura cylindrica, Laurencia papillosa Red Sea, Egypt CHCl3/MeOH (2:1, v/v). Glycolipid separation using acetone on SiO2 columns Glycolipid-rich extracts

(DGDG)
LC-MS/MS [87][103]
Red Sea, Egypt MeOH/CHCl3 (2:1, v/v). Sulfolipid isolation: diethylaminoethyl-cellulose column (CHCl3/MeOH (6:4, v/v) and NH3) Sulfolipids (SQDG) GC-MS, GC-FID, LC-MS/MS, IR [75][89]
Gigartina tenella Sagami Bay, Kanagawa, Japan Acetone. Extract partitioned with EtOAc/H2O (3:1, v/v). Organic layer dissolved in EtOAc/MeOH/H2O (100:20:5, v/v) and chromatographed on SiO2 column Glycolipid (Sulfolipids) 1H and 13C NMR, HR-FAB-MS [91][107]
Gracilaria gracilis Ganzirri lagoon and Margi channel, Eastern Sicily, Italy CHCl3, Et2O in Soxhlet extractor FA GC-FID [92][94]
Gracilariopsis longissima Mar Piccolo of Taranto, Italy CHCl3/MeOH/H2O (2:1:1, v/v) FA 1H and 13C NMR, 1D and 2D NMR, GC-FID [93][108]
IZ (mm) Hypnea musciformis, Osmundaria obtusiloba, Porphyra acanthophora, Pterocladiella capillacea Buzios, Rio de Janeiro, Brazil Acetone insoluble material extracted with CHCl3/MeOH (2:1 and 1:2, v/v). Extract partitioned on SiO2 column (CHCl3, acetone or MeOH) Glycolipid-rich extracts (Sulfolipids, Glycosyldiacylglycerols) HPTLC [81][97]
Jania corniculata, Laurencia papillosa Suez Canal, Egypt EtOH (70%), CH2Cl2 FA GC-MS [94][93]
Laurencia okamurai Nanji Island in the East China Sea, Zhejiang Province, China EtOH (95%) extract partitioned with Et2O and fractionated by SiO2 (gradient system: petroleum ether –CH2Cl2 (10:0 → 1:9)), Sephadex column, and purification by semi-preparative C18 HPLC FA ethyl esters [(9Z,12Z,15Z,18Z,21Z)-ethyl tetracosa-9,12,15,18,21-Pentaenoate, (10Z,13Z)-ethyl nonadeca-10,13-dienoate, (9Z,12Z)-ethyl nonadeca-9,12-dienoate, (Z)-ethyl octadec-13-enoate (4), and (Z)-ethyl hexadec-11-enoate] 1H and 13C NMR, 1D and 2D NMR, IR, HR-EI-MS [95][109]
Laurencia spp. Pulau Tioman, Pahang, Pulau Karah, Terengganu, Pulau Nyireh, Terengganu, Malaysia MeOH. Extract partitioned with Et2O and H2O and fractionated by SiO2 column (hexane/EtOAc) Sesquiterpenes (Halogenated sesquiterpenes) 1H and 13C NMR, LREIMS, HREIMS [96][110]
Osmundaria obtusiloba Buzios, Rio de Janeiro, Brazil Acetone insoluble material extracted with CHCl3/MeOH (2:1 and 1:2, v/v). Extract partitioned (CHCl3/MeOH/0.75% KCl (8:4:3, v/v)). Fractionation on SiO2 column (CHCl3, acetone and MeOH). MeOH fraction purified on SiO2 column (CHCl3/MeOH, 90:10, v/v) Glycolipids (Sulfoglycolipids) 1H and 13C NMR, ESI-MS/MS [97][111]
Palmaria palmata, Grateloupia turuturu Batz-sur-Mer, France CH2Cl2/MeOH (2:1, v/v), MeOH/H2O (1:1, v/v) Polar lipids 1H and 13C NMR [98][112]
Pyropia orbicularis Maitencillo, Chile MeOH, acetone, CH2Cl2 Solanaceae, Euphorbiaceae, Combretaceae Ashwaganda, asthma-plant, black myrobalan India Fruits, leaf, stem, and root from W. somnifera and E. hirta and fruits, leaf, stem, and stem bark from T. chebula EtOAc Sterols fraction [66][67]
Kaempferia pandurata Roxb. (synonym of Boesenbergia rotunda (L.) Mansf.) and Senna alata (L.) Roxb. Zingiberaceae and Fabaceae, respectively Fingerroot and candle bush, respectively Indonesia Leaf of S. alata and rhizome of K. pandurata EtOH (96%) Sterols and triterpenoid [67][68]
Zygophyllum oxianum Boriss. Zygophyllaceae Beancaper Uzbekistan Leaves, stems, and fruit Acetone and CHCl3:MeOH (2:1, v/v) for total lipid extraction. Total lipids from each plant part separated in SiO2 columns. Neutral lipids eluted with CHCl3; glycolipids with acetone; phospholipids with MeOH. Total lipid extract from leaves, stems and aerial organs (hydrocarbons, triterpenol and steryl esters, triacylglycerols, free FA, sterols, phospholipids) [68][59]
In order to obtain a class of lipids or a particular lipid, the total lipid extract can be fractionated into different groups of lipids, depending on the polarity of the compounds, by thin-layer chromatography (TLC) or by column chromatography. Thus, for example, to recover the neutral lipids (e.g., sterol esters and triacylglycerols) by column chromatography, the extract can be eluted with CHCl3, followed by acetone to elute the glycolipids and, finally, with MeOH to elute the phospholipids, as mentioned for the leaves, stems and fruit of Zygophyllum oxianum [68][59]. The majority of the studies on antimicrobial plant lipids obtained and analyzed FA and their derivatives. FA have been isolated from a series of plant parts by using MeOH/benzene/sulfuric acid, 85% ethanol or supercritical fluid extraction (SFE) with CO2 and analyzed as FAME [40][43][45][51][54][56][56,60,61,62,63,64].
Mixtures of FA and FAME were obtained, but it was not clear if these FA were found in the free or esterified forms, since the derivatization methods (methylation) used in these studies convert free and esterified FA to FAME. However, because of their high abundance, presumably, the referred FA were esterified to other lipids. Several oxylipins were retrieved from roots, stems, and leaves of Brazilian joyweed (Alternanthera brasiliana) by extracting with EtOH and EtOAc [46][65]. Acetylenic FA were isolated from the roots of Pentagonia gigantifolia with 95% ethanol [64][38].
Other lipid classes isolated from plants for antimicrobial testing include sterols and sterol derivatives, glyceroglycolipids, and sphingolipids (Figure 12 and Table 1). The first group includes free sterols, steryl glycosides, and acyl steryl glycosides. Free sterols have been extracted together with triterpenes from the seeds of date palm (Phoenix dactylifera) by using CHCl3 and acetone [47][66], from several parts of Withania somniferaEuphorbia hirta, and Terminalia chebula with EtOAc [66][67] and leaves of candle bush (Senna alata) and rhizomes of fingerroot (Kaempferia pandurata) with EtOH [67][68]β-sitosterol 3-O-β-D-glucopyranoside, a steryl glycoside, was obtained from the leaves of Sendudok (Melastoma malabathricum) with CHCl3/acetone/MeOH [58][69] and the acyl steryl glycosides sitosteryl 3-β-O-glucoside 6’-O-palmitate and stigmasteryl 3-β-O-glucoside 6’-O-palmitate were obtained from the roots of capotiraguá (Blutaparon portulacoides) with EtOH [44][70]. Glyceroglycolipids, namely sulfoquinovosyldiacylglycerols (SQDG) were retrieved from neem (Azadirachta indica) leaves by extracting with MeOH and separating by SiO2 column chromatography with CHCl3/MeOH [59][71] or extracted with petroleum ether and re-extracted with MeOH [60][72].
In the group of sphingolipids, different chemical structures were identified belonging to different subclasses: ceramides and glycosphingolipids, also known as cerebrosides (Figure 12 and Table 1). Artemceramide-B was identified from the roots of Artemisia incisa after extraction with MeOH and recovered by SiO2 column chromatography after elution of the extract with CH2Cl2/MeOH following previous elution with n-hexane/EtOAc [48][73]. A cerebroside (soya-cerebroside I), a sphingolipid glycoside (1-O-β-D-glucopyranosyl(2S,3S,4R,10E)-2-[(2’R)-2-hydroxytetracosanoylamino]-1,3,4-octadecanetriol-10-ene), and its aglycone form (2S,3S,4R,10E)-2-[(2’R)-2-hydroxytetra-cosanoylamino]-1,3,4-octadecanetriol-10-ene) were isolated from the stems of cucumber (Cucumis sativus) by CHCl3 fractionation of the methanolic extract [50][74]. New glycosphingolipids were isolated and characterized from the fruits of fiddle leaf fig (Ficus pandurata), panduramides A–D and newbouldiamide [62][75], and from the woods of the giant-leaved fig (Ficus lutea), 1-O-β-D-glucopyranosyl-(2S,3R,5E,12E)-2N-[(2′R)-hydroxyhexadecanoyl]-octadecasphinga-5,12-dienine, commonly named lutaoside [61][76]. All these compounds are inhibitors of microbial growth, except panduramides A–D and newbouldiamide that did not reveal any activity (Table 2).
Table 2. Antimicrobial activity of plant lipids or plant lipid-rich extracts.
Botanical Name Tested (Micro)Organisms Antimicrobial Testing Method/Evaluation Reference Antimicrobial (Positive Control) MIC, MBC, Diameter of Inhibition Zone (in mm) or Other Isolated Lipids or Lipid Mixtures Ref.
Sesuvium portulacastrum L. G(+) bacteria: Bacillus subtilis NCIM 2063, B. pumilus NCIM 2327, Micrococcus luteus NCIM 2376 and S. aureus NCIM 2901; G(-) bacteria: P. aeruginosa NCIM 5031, K. pneumoniae NCIM 2957 and E. coli NCIM 2256. Ten isolates of MRSA and of MRSA NCTC 6571. Human pathogenic yeast type fungi: Candida albicansC. kruseiC. tropicalis and C. parapsilosis and mould fungi: Aspergillus nigerA. flavus, and A. fumigatus Inhibition zone (IZ) by disk diffusion test and minimum inhibitory concentration (MIC) by broth macrodilution method Ciprofloxacin for bacteria, methicillin, oxacillin and vancomycin for MRSA and amphotericin-B for fungi MIC: 0.25 mg/mL for B. subtilis, 0.5 mg/mL for S. aureus, MRSA, P. aeruginosaK. pneumoniae and C. albicans, and 1.0 mg/mL for E. coli; MBC: 0.5 mg/mL for B. subtilis, 1.0 mg/mL for S. aureus, MRSA and K. pneumoniae, and 2.0 mg/mL for P. aeruginosa and E. coli; MFC: 1 mg/mL for C. albicans FAME [43][60]
Blutaparon portulacoides (A. St.-Hil.) Mears Trypanosoma cruziLeishmania amazonensisS. aureus ATCC 25923 and 7+ penicillinase producer, Streptococcus epidermidis (6ep), E. coli ATCC 10538, Streptococcus mutans (9.1), Streptococcus sobrinus (180.3) Crude extracts and isolated compounds added to the trypomastigote-containing blood samples and incubated 24 h at 4 °C. Trypanocidal activity evaluated by counting the remaining trypomastigotes. L. amazonensis amastigote viability assessed colorimetrically by the reduction of a tetrazolium salt (MTT). Antimicrobial activity measured by the well-diffusionmethod in double layer Gentian violet for trypanocidal activity and gentamicin for antibacterial assays MIC: 100–500 μg/mL in T. cruzi trypomastigotes and 14–500 μg/mL in L. amazonensis amastigotes; 50 μg/mL in E. coliS. aureus ATCC 25923, S. aureus (7+) and 500 μg/mL in S. epidermidisS. mutans, and S. sobrinus Acyl steryl glycosides (sitosteryl 3-β-O-glucoside 6’-O-palmitate and stigmasteryl 3-β-O-glucoside 6’-O-palmitate) [44][70]
Arthrocnemum indicum (Willd.) Moq., Salicornia brachiata Roxb., Suaeda maritima (L.) Dumort. and Suaeda monoica Forsk. G(+) bacteria: B. subtilis NCIM 2063, B. pumilus NCIM 2327, M. luteus NCIM 2376, and S. aureus NCIM 2901; G(-) bacteria: P. aeruginosa NCIM 5031, K. pneumoniae NCIM 2957, and E. coli NCIM 2256; ten isolates of MRSA and of MRSA NCTC 6571; yeasts (C. albicans, C. krusei, C. tropicalis, and C. parapsilosis) and molds (A. nigerA. flavus, and A. fumigatus) Disk diffusion method and broth macrodilution method Ciprofloxacin for bacteria, methicillin, oxacillin and vancomycin for MRSA and amphotericin-B for fungi MIC of 0.06 mg/mL of S. brachiata extracts against B. subtilisS. aureus, and MRSA, and 0.5 mg/mL against P. aeruginosa; MIC of 0.5 mg/mL of all FAME extracts against E. coli and K. pneumoniae; MBC of 0.1 mg/mL of S. brachiata extracts against P. aeruginosa and of 1.0 mg/mL of all FAME extracts against E. coli and K. pneumoniae FAME [45][61]
Alternanthera brasiliana E. coli ATCC 25922, B. subtilis ATCC 6623, P. aeruginosa ATCC 15442, M. luteus ATCC 9341, and S. aureus ATCC 25923 Microdilution broth method according to NCCLS standardization Tetracycline and norfloxacin MIC: 50 μg/mL against B. subtilisM. luteus, and S. aureus Linoleate oxylipins [46][65]
Phoenix dactylifera L. Bacillus cereus and E. coli Disk diffusion method Streptomycin 20 mm against E. coli and 17 mm against B. cereus at 1 mg/mL of the acetone extract Sterol and triterpenes [47][66]
Asphodelus aestivus Brot. G(+) bacteria: S. aureus ATCC 6538-p, E. faecalis ATCC 29212; G(-) bacteria: E. coli ATCC 29998, K. pneumoniae ATCC 13883, P. aeruginosa ATCC 27853); yeasts: C. albicans ATCC 10239 and C. krusei ATCC 6258 Disk diffusion method and broth microdilution tests according to the recommendations of Clinical and Laboratory Standards Institute (CLSI) Ampicillin, ciprofloxacin and fluconazole MIC: 512 μg/mL against S. aureusE. faecalisK. pneumoniae, and C. albicans FA (4:0, 6:0, 8:0, 10:0, 16:0, 18:0, 21:0, 24:0, 14:1, 15:1, 18:1n9t, 20:1, 24:1, 18:2, 18:2n6t, 18:2n6c, 20:2n6, 20:3n3, 22:6n3, and others unidentified) [38][54]
Artemisia incisa Pamp. S. epidermidis and S. aureus2/MeOH (9:1, v/v) following previous elution with n Agar well diffusion method and MIC determined by a referenced method-hexane/EtOAc (5:4,  Streptomycin and tetracycline S. epidermidis (0.0157 mg/mL) and S. aureus (0.0313 mg/mL)v/v) Artemceramide-B Artemceramide-B [48][73[48][73]
] Pteranthus dichotomus Forssk. (also known as P. echinatus Desf.) Caryophyllaceae   Algerian Sahara Aerial parts
Pteranthus dichotomus Forssk. (also known as P. echinatus Desf.) S. aureus ATCC 25923, E. coli ATCC 25922, K. pneumoniae ESBL, and Enterobacter sp. ESBL Disk diffusion method Gulf of Eilat, Red SeaGentamicin and ampicillin   MeOH/CHCl3, RP on a C18 column (decreasing percentage of H2O in MeOH)P. dichotomus BuOH extracts at 0.25 g/mL (8 mm against E. coliK. pneumoniae ESBL); P. dichotomus EtOAc extract at 0.5 g/mL (7 mm against E. coli), at 65 mg/mL (8.33 mm against S. aureus), and at 0.25 g/mL (7 mm against Enterobacter sp. ESBL) Steroidal glycosideMeOH/H20 mg/mouse/7 days by giving 50% protection

(Eryloside)2O (80:20, v/
BuOH fraction contained 1-O-palmitoyl-3-[ 1Ov). Aqueous phase extracted successively with petroleum ether, EtOAc and n-BuOH. EtOAc fraction contained the sterols and steryl glycoside. BuOH fraction contained the glyceroglycolipids and the cerebroside. -(6-sulfo-α-D-quinovopyranosyl)-glycerol, 1,2-di-O-palmitoyl-3-O-(6-sulfo-α-D-quinovopyranosyl)-glycerol and soya cerebroside I. EtOAc fraction contained stigmat-7-en-3-ol, spinasterol, β-sitosterol and H and 13β-sitosterol-3-O-glucosideC NMR, UV, IRBuOH fraction contained the compounds: 1-O-palmitoyl-3-O-(6-sulfo-α-D-quinovopyranosyl)-glycerol, 1,2-di-O-palmitoyl-3-O-(6-sulfo-α-D-quinovopyranosyl)-glycerol and soya cerebroside I. EtOAc fraction contained the compounds: stigmat-7-en-3-ol, spinasterol, β-sitosterol and β-sitosterol-3-O-glycoside [49]85][101]
[141][
Erylus lendenfeldi Antifungal Yeast: C. albicans[78  ]172[49][78]
Cucumis sativus L.
  MIC (µg/mL) 15.6 [141][172] Cucumis sativusCucurbitaceae  L. AntiviralPhytopathogenic fungi (Cucumber Pythium aphanidermatumChina Viruses: Japanese encephalitis

virus (JEV), encephalomyocarditis (EMC) virus
96-well microtiter plates   CC50 (µg/mL)/EC50 (µg/mL)/TI

JEV: 7.8/3.9/2.0
[86][102]
]
Erylus placenta Porifera (Demospongiae) Hachijo Island, Japan
Erylus placenta Antifungal G(+): S. aureus

G(-): E. coli

Fungus: Mortierella ramanniana

Yeasts: S. cerevisiae (cdc28, act1-1, erg6)
n-PrOH/H2O (3:1, v/v). Extracts partitioned between H2O and CHCl3. H2O layer partitioned between n-BuOH and H2O. BuOH fraction separated by C18 flash (n-PrOH/H2Stems Botryosphaeria dothideaFusarium oxysporum f.sp. cucumerinum, and Botrytis cinerea); phytopathogenic bacteria [G(-): Xanthomonas vesicatoria ATCC 11633, Pseudomonas lachrymans ATCC 11921, and G(+) B. subtilis ATCC 11562] Mycelial radial growth inhibition assay and antifungal activity (pour plating method in potato dextrose agar medium) for fungi and agar-well diffusion assay for bacteria Carbendazim for fungi and streptomycin sulfate for bacteria O (1:9, 3:7, 5:5, and 8:2, v/v) and CHCl3/MeOH/H2O(6:4:1, v/v))5.5–100 inhibitory rate of mycelia growth inhibitory activity; IC50 of B. subtilis (50.2–110.9 μg/mL), X. vesicatoria (25.6–64.5 μg/mL), P. lachrymans (15.3–37.3 μg/mL) for sphingolipidsCHCl3 fraction of the crude methanolic extract Steroidal glycoside

(Sokodosides)Sphingolipids [(2S,3S,4R,10E)-2-[(2’R)-2-hydroxytetracosanoylamino]-1,3,4-octadecanetriol-10-ene, 1-O-β-D-glucopyranosyl-(2S,3S,4R,10E)-2-[(2’R)-2-hydroxytetracosanoylamino]-1,3,4-octadecanetriol-10-ene and soya-cerebroside I]Sphingolipids [(2
1H and  Disk diffusion method13C NMR, GC-FID, UV  [ IZ (mm)

M. ramanniana: 11–12

S. cerevisiae: 8–18S,3S,4R,10E)-2-[(2’142R)-2-hydroxytetracosanoylamino]-1,3,4-octadecanetriol-10-ene, 1-O-β-D-glucopyranosyl-(2S,3S,4R,10E)-2-[(2’R)-2-hydroxytetracosanoylamino]-1,3,4-octadecanetriol-10-ene and soya-cerebroside I]
[50][74]][174] [142][50][74]
[174] Excoecaria agallocha Euphorbiaceae
Excoecaria agallocha G(+) bacteria: B. subtilis NCIM 2063, Blind-your-eye mangrove B. pumilusIndia Leaves  NCIM 2327, M. luteus NCIM 2376, S. aureus NCIM 2901; G(-) bacteria: P. aeruginosa NCIM 5031, K. pneumoniae NICM 2957, and E. coli NCIM 2256; yeasts: C. albicansC. kruseiC. tropicalis, and C. parapsilosis Disk diffusion method for antibacterial and antifungal susceptibility tests; MIC tested in Mueller-Hinton broth for bacteria and yeast nitrogen base for yeasts by two-fold serial dilution method Ciprofloxacin and amphotericin B MIC: 0.125 mg for B. subtilis and S. aureus Antifungal, Antiviral Yeast: C. albicans;

Fungus: A. niger

Virus: HSV-1, 0.5 mg for P. aeruginosa
Disk diffusion method; plaque reduction assay (antiviral) and K. pneumoniae, and 1.0 mg for   E. coli
Euryspongia sp.; MBC: 0.25 mg for B. subtilis Porifera (Demospongiae) and S. aureus, 1.0 mg for MIC (µg/mL)/IZ (mm) Light House Reef, Koror, Palau MeOH. Extracts fractionated by HP20SS column (acetone/H2O)P. aeruginosa and K. pneumoniae, and 2.0 mg for E. coli; MFC: 1 mg for C. albicansC. krusei and C. parapsilosis

Dry MeOH, benzene and sulfuric acid (200:100:10, v/v)
FAME FAME C. albicans: 60/8,

A. niger: 80/13

HSV-1: 9.37–15.62%
[87][
Euryspongia sp.Steroid sulfates (Eurysterols)103][51]
Antifungal Yeasts: C. albicans1H and 13C NMR, ESI-MS, UV, IR[  (ATCC 32354, wild-type) (ATCC 90873, amphotericin B-resistant)[ Liquid antifungal assay62143][167] Amphotericin B MIC (µg/mL): 15.6–62.5 [143][167[51][62]
] Albizia adianthifolia Antibacterial, Antiviral G(+):
]  (Schumach) and Pterocarpus angolensis (DC) Fabaceae
Albizia adianthifolia (Schumach) and Pterocarpus angolensis (DC) Fasciospongia sp.Bacteria (E. coliB. subtilisFlat crown Albizia and African teak, respectively P. aeruginosaB. subtilisNigeria and Botswana, respectively S. aureus) and yeast ( RRL B-94

G(-): Heartwood of A. adianthifolia and stem bark of P. angolensis
C. albicans)E. coli NRRL B-3703

Virus: HSV-1n-hexane, CHCl3, MeOH, and 10% MeOH (aq)
Modified agar overlay method Chloramphenicol for bacteria and miconazole for fungi MIQ: 1 μg of  Porifera (Demospongiae)Disk diffusion methodn Chloramphenicol (bacteria), Acyclovir (virus)
Fasciospongia sp.Cape Leeuwin, Western Australia Antibacterial G(+):

S. aureus (ATCC 25923, ATCC 9144), B. subtilis (ATCC 6051, ATCC 6633)

G(-):

E. coli (ATCC 11775), P. aeruginosa (ATCC 10145)

Yeast: C. albicans (ATCC 90028)EtOH extract partitioned into n-BuOH and H2O soluble fractions. n-BuOH fraction subsequently defatted by sequential trituration in n-hexane and CH2Cl2 soluble fractions. CH
-hexane and CHCl3 extracts of A. adianthifoliaMIC (µg/mL)/IZ (mm)

PI(%)

E. coli: 60/13

B. subtilis: 40/16

HSV-1: 18.75–46.87%
[75][89]
2Cl2 fractions subjected to SPE or HLPC Meroterpene

(Meroterpene sulfate fascioquinol)
1H and 13C NMR, HR-ESI-MS, UVn-hexadecanoic acid (palmitic acid); oleic acid; chondrillasterol; stigmasterol, 24S 5α-stigmast-7-en-3-ol; 9,12-octadecadienoic acid (Z,Z)-, methyl ester; trans-13-octadecanoic acid, methyl ester; tetradecanoic acid; hexadecanoic acid, methyl ester; octadecanoic acid  against E. coli; 50 μg of n-hexane and CHCl3 extracts of A. adianthifolia against P. aeruginosa; 50 μg of CHCl3[52][79]
 extract of P. angolensis against B. subtilis and 100 μg of n-hexane extract of P. angolensis against B. subtilis 96-well microtiter plate and C. albicans n-hexadecanoic acid (palmitic acid); oleic acid; chondrillasterol; stigmasterol, 24S 5α-stigmast-7-en-3-ol; 9,12-octadecadienoic acid ( Penicillin, Fluconazole IC50Z,Z)-, methyl ester; trans-13-octadecanoic acid, methyl ester; tetradecanoic acid; hexadecanoic acid, methyl ester; octadecanoic acid  (µM)

S. aureus: 0.95–2.5

B. subtilis: 0.3–7.0[52][79]
[144][186] [144][186] Baphia massaiensis Jasmine pea Botswana Seeds n-hexane/1-propanol (3:1, v/
Baphia massaiensis E. coliB. subtilis, P. aeruginosaS. aureus, and v) with Soxhlet extractor Seed oil (total FA) C. albicans Ulva rigida Antibacterial G(+): S. agalactiae, S. aureus (ATCC 25923), S. aureus (ATCC 6538), E. faecalis (ATCC 29212), Micrococcus sp.

G(-): Vibrio tapetis (CECT4600), V. anguillarum (ATCC 12964T), V. alginolyticus (ATCC 17749T), E. coli O126-B16 (ATTC 14948), E. coli (ATCC 25922), E. coli (ATCC 8739), Pseudomonas cepacia, P. fluorescens (AH2), P. aeruginosa (ATCC 27853), Aeromonas salmonicida (LMG3780), A. hydrophila B3, S. typhimurium (C52)

Halichondria sp.Yeast: C. albicans[53 Agar well diffusion method  (ATCC10231) Porifera (Demospongiae)Disk diffusion method and broth microdilution technique   Unten Port, Okinawa, Japan
HalichondriaNot mentioned  sp. Antibacterial Antifungal G(+): M. luteus, B. subtilis

G(-):

E. coli

Yeasts: C. neoformans,

C. albicans,

Fungi: Paecilomyces variotii, A. niger, A. fumigatusMethanolic extract partitioned between H2O and EtOAc. EtOAc soluble material subjected to SiO2 column (CHCl3/MeOH, (95:5, v/v) and petroleum ether/Et2O (9:1, v/v))10 mm of inhibition zone against E. coli and S. aureus, and 16 mm against 
][80]
B. subtilis Seed oil (total FA) IZ (mm) Sesquiterpenoids

(Halichonadins)


6.3–16.3
[ Broth microdilution method153]  H and  MIC (µg/mL)

M. luteus: 0.52

[80]
C. neoformans[ Cassia tora L. (or Senna tora L. Roxb.) Sickle Senna India Leaves and stem Petroleum ether with Soxhlet extractor FA (the major were palmitic acid, linoleic acid, linolenic acid, margaric acid, melissic acid, and behenic acid) [
27] Cassia tora L. (or Senna tora L. Roxb.)39] MRSA, MSSA, B. subtilis,[55]
 and P. aeruginosa Broth microdilution method Ampicillin MIC for all bacteria between 125–1000 μg/mL FA (the major were palmitic acid, linoleic acid, linolenic acid, margaric acid, melissic acid, and behenic acid) [39][55] Trigonella foenum-graecum L.
13C NMR, EI-MS, IR : 0.0625

C. albicans: 2.09

P. variotii: 1.04

A. niger: 1.04 1.04
[145][187] [145 Macroalgae–Rhodophyta
][ Porifera (Demospongiae) ]


A. fumigatus:187]   MeOH extract partitioned between H2O and EtOAc. EtOAc-soluble material subjected to SiO2 column (n-hexane/EtOAc, 1:1 → MeOH). MeOH fraction subjected to SiO2 column (CHCl3 Western Carolines, Palau
Antibacterial Antifungal G(+): M. luteus

Yeast: C. neoformans

Fungi: T. mentagrophytes
/MeOH, 95:5 → 7:3). CHCl3/MeOH (7:3) fraction separated on SiO2 column (EtOAc/MeOH, 5:1 → MeOH) Sesquiterpenoid

(Halichonadins)
1H and 13C NMR, ESI-MS, HR-ESI-MS, IR     MIC (µg/mL)

M. luteus: 4

T. mentagrophytes: 8–16

C. neoformans[146][188]
: 16 [146][188] Fenugreek India
Trigonella foenum-graecum L. G(-) bacteria: E. coli and P. aeruginosa; G(+) bacteria: S. aureus and Streptococcus pyogenes; acid-fast bacteria: Seeds M. tuberculosisSupercritical fluid extraction (40–60 °C and 10–25 Mpa) Conjugated linoleic acid methyl ester, saturated FAME, steroids ; fungi:  Chondria armata Antibacterial, Antifungal G(+): S. aureus

G(-): E. coli, P. aeruginosa, S. typhi, Salmonella flexneri, Klebsiella sp., V. cholerae

Yeast: C. albicans, C. neoformans, Rhodotorula sp.

Fungi: Aspergillus fumigatus, A. niger[54][63]
Quercus leucotrichophora A. Camus Fagaceae Banjh oak India Fruits 85% aqueous EtOH. Ethanolic extract fractionated with hexane and EtOAc using Soxhlet extractor. Hexane extract was analyzed. FAME [40][56]
C. albicansA. niger and A. clavatus; parasite Plasmodium falciparum (etiological agent of malaria) Antimicrobial activity assessed by broth dilution method, anti-tuberculosis activity assessed by the slope method, in vitro anti-malarial assay according to a microassay protocol Gentamycin, chloramphenicol, ciprofloxacin and norfloxacin for bacteria; isoniazid and rifampicin for mycobacteria; nystatin and greseofulvin for fungi; chloroquine and quinine as anti-malarials MIC values of 100, 250, 125 μg/mL towards E. coliS. aureus, and S. pyogenes and P. aeruginosa, respectively. MFC value of 250 μg/mL of C. albicans. MIC value of 100 μg/mL toward M. tuberculosis Disk diffusion method and of 0.29 μg/mL toward P. falciparum Conjugated linoleic acid methyl ester, saturated FAME, steroids [54][63]
Streptomycin, Quercus leucotrichophora, A. Camus G(+) bacteria: B. subtilis CH₂Cl₂, purified by chromatography Sesterterpenoids

Haliclona simulans Anti-mycobacterial

Antitrypanosomal
Acid-fast bacterium: Mycobacterium marinum

Parasitic trypanosomatida: T. brucei


Nystatin 1 < IZ ≤ 4 [88 Broth microdilution method] Gentamycin MIC (µM): M. marinum: 156.9–288.8

T. b. brucei: 4.58–21.56[104]
Haliclona simulans Porifera (Demospongiae) Kilkieran Bay, Galway, Ireland Acetone and MeOH extracts subjected to HP20 chromatography (100% H2O → 100% MeOH). Fractionated on flash forward system. SiO2 column (100% hexane → 100% EtOAc) Steroids

(24-vinyl-cholest-9-ene-3β,24-diol, 20-methyl-pregn-6-en-3β-ol,5α,8α-epidioxy, 24-methylenecholesterol)
1H- and 13C NMR, GC-MS [147][170] [147][170]  and S. aureus; G(-) bacteria: P. aeruginosa and E. coli Chondrus crispus, Gracilaria vermiculophylla, Porphyra dioicaDisk diffusion method for antibacterial susceptibility tests; MIC was tested in Mueller-Hinton broth for bacteria by two-fold serial dilution method Ciprofloxacin Antibacterial, Antifungal G(+): Listeria innocua (NCTC 11286), B. cereus (ATCC 11778), E. faecalis (LMG S 19456 5002), Lactobacillus brevis (LMG 6906), S. aureus (ATCC 6538), MRSA

G(-): E. coli (ATCC 8739), Salmonella enteritidis (ATCC 3076), P. aeruginosa (ATTC 10145)

Yeast: Candida spp. (CCUG 49242)
Disk diffusion method Ampicillin (L. innocua), Cycloheximide (
Jaspis stelliferaCandida spp.), Chloramphenicol (other microorganisms) Porifera (Demospongiae)
Jaspis stelliferaIshigaki Island, Okinawa, Japan Antibacterial

Antifungal
G(+): Sarcina lutea

Yeast: C. neoformans

Fungi: T. mentagrophytesMeOH. EtOAc soluble material subjected to SiO2 column (CHCI3/MeOH, 9:1 and hexane/EtOAc, 3:7, v/v
MIC: 0.125 mg/mL for B. subtilis and S. aureus; 0.5 mg/mL for P. aeruginosa and 1.0 mg/mL for E. coli FAME ). EtOAc-soluble material subjected to SiO2 columns and C18 HPLCIZ (mm)  Nortriterpenoids

(Jaspiferals)

C. crispus: 5 < IZ ≤ 20

G. vermiculophylla: 10 < IZ ≤ 15

P. dioica: 5 < IZ ≤ 12[40
[89] 1H and ][56] [105]
13C NMR, EI-MS, UV, IR [148][181]   MIC (µg/mL)

S. lutea: 50

C. neoformans: 50

T. mentagrophytes: 12.5
[148][181] Quercus leucotrichophora A. Camus Banjh oak Garhwal region of Himalaya Leaves and bark MeOH
Quercus leucotrichophora A. CamusFA; linoleic acid in stem bark and leaves extracts and  Falkenbergia

(heteromorphic sporophyte of Asparagopsis taxiformis)G(-) bacteria: E. coli MTCC-582 and P. aeruginosa MTCC-2295; G(+) bacteria: S. aureus
cis-vaccenic acid in stem bark  MTCC-3160, B. subtilis Antibacterial[55][81]
 MTCC-441 and S. pyogenes MTCC-1924 Disk diffusion method G(+): Ampicillin S. epidermidis, S. aureus, B. subtilisIZ of both extracts against all microorganisms: 8.53 ± 0.50 to 19.07 ± 0.31 mm

G(-): V. vulnificus (MTCC 1145), V. parahaemolyticus (MTCC 451), FA; linoleic acid in stem bark and leaves extracts and cis-vaccenic acid in stem bark
V. harveyi (MTCC 3438), V. alginolyticus (MTCC 4439), V. alcaligenes (MTCC 4442), P. aeruginosa, K. pneumoniae[55] (Manoalides) 1H and 13C NMR, UV, IR [
Luffariella geometrica Antibacterial G(+): S. aureus, Micrococcus sp.

Broth dilution method Yeast: Chloramphenicol, Nalidixic acid S. cerevisiaeIZ (mm)/MIC (µg)/MBC (µg)

S. epidermidis: 21/1250/270

S. aureus
Disk diffusion method: 21/750/170

B. subtilis
 : 23/750/180

V. vulnificus: 31/750/90

V. parahaemolyticus: 28/750/110

V. harveyi: 26/750/60

V. alginolyticus: 32/500/80

V. alcaligenes: 33/500/50

P. aeruginosa: 19/1250/420

K. pneumoniae: 15/1250/380
Luffariella geometrica Porifera (Demospongiae) Great Australian Bight, Australia CH2Cl2. Sequential fractionation to obtain pure compounds[ Sesterterpenes

(Luffarins)
90 1H and 13 EC (µg/disk)

S. aureus: 100[81]
][106]
C NMR, EI-MS, UV, IR

Micrococcus sp.: 100[149][178] [149][178] Vitex altissima L., V. negundo L. and V. trifolia L. Lamiaceae Peacock chaste tree, Chinese chaste tree, and simpleleaf chastetree, respectively India Leaves
Vitex altissima L., V. negundo L. and V. trifolia L.Dry MeOH/benzene/sulfuric acid (200:100:10, v Culex quinquefasciatus (early fourth-instar larvae)/v) FAME Larvicidal activity analyzed according to standard procedures (WHO-VBC 81.807, 1981) Not mentioned V. trifolia (LC Galaxaura cylindrica, Laurencia papillosa50 = 9.26 ppm and LC90 Antiviral = 21.28 ppm) Virus: HSV-1 Plaque reduction assay Acyclovir
Luffariella variabilis[ Porifera (Demospongiae)FAME Western Carolines, PalauInhibition (%) CH₂Cl₂, purified by chromatography

L. papillosa
Sesterterpenoids

: 9.37–31.25

56]
G. cylindrica: 15.62–28.12[ (Manoalide) 1H and 13C NMR, UV, IR56[87]
Luffariella variabilis[103]
[ Antibacterial150][ G(+): Streptomyces pyogenes, S. aureus  180   Active against S. pyogenes, S. aureus[64]
][64] [150][180] Linum usitatissimum L. Linaceae Common flax or linseed Algeria Seeds
Linum usitatissimumPetroleum ether with Soxhlet extractor  L. Antibacterial, AntiviralA. flavus MTTC 2799 and A. ochraceus CECT 2092 Determination of percent mycelial inhibition by growth radial technique on solid medium and by biomass technique on liquid mediumFAME G(+): B. subtilis NRRL B-94

G(-): E. coli NRRL B-3703

Virus: (HSV-1)
Disk diffusion method Chloramphenicol (bacteria), Acyclovir (virus) 151][179]
Antibacterial G(+): S. aureus, B. subtilis

G(-): E. coli, P. aeruginosa

Yeast: 
Not mentioned C. albicanAntifungal index of FAME in solid medium: 54.19 ± 0.85 at 10 μL in A. flavus and 40.48 ± 0.12 at 90 μL for A. ochraceus at 90 μL MIC (µg/mL)/IZ (mm)

PI(%)

L. papillosa

E. coli: -/8

B. subtilis: -/11FAME


HSV-1: 40.62–59.37%

[41][57]
[41][57]
G. cylindrica

E. coli: 80/11

B. subtilis: 80/11

HSV-1: 45.87–59.37%
[75][89] Scaphium macropodum (Miq.) Beumee ex. Heyne Malvaceae Malva nut or Kembang semangkok Malaysia Stem bark
Scaphium macropodum (Miq.) Beumee ex. Heyne Mycobacterium smegmatisE. coliS. typhimurium
Gigartina tenella Antiviral HIV-reverse transcriptase type 1     IC50 11.2 µM [91][107]
s     Active against S. aureus, B. subtilis [151][179] B. subtilis, and S. aureus Inhibitory activity of the extract by disk diffusion method; broth microdilution assay (MTT assay) was used to determine the MIC; MBC was determined via streak plate method Ampicillin and rifampicin IZ of 10.67 ± 0.58 mm in MeOH S. aureus and of 9 mm in P. aeruginosa at 0.25 mg/mL. S. aureus showed the lowest MIC (0.78 mg/mL) and MBC (3.13 mg/mL). For M. smegmatis, MIC value was 3.13 mg/mL and MBC was 25 mg/mLMethyl hexadecanoate, hexadecanoic acid <n-> Melophlus sarasinorum[ Porifera (Demospongiae)Methyl hexadecanoate, hexadecanoic acid < Makassar, Sulawesi Island, Indonesia
Melophlus sarasinorum Antibacterial

Antifungal
G(+): B. subtilis (DSM2109)

G(+): E. coli (DSM10290)

Yeast: S. cerevisiae
Acetone and MeOH. Extract partitioned between EtOAc and H2O. Aqueous extract on HP20 (MeOH, H2O). MeOH eluate on C18 (MeOH and Hn->57 2O, gradient elution)[57 Disk diffusion methodSteroidal glycosides

(Sarasinoside)]]
1H and [82]
13C NMR, HR-ESI-MS, LC-MS, UV   IZ (mm)

B. subtilis: 9

S. cerevisiae: 10–13
[82] [152][173] Gracilaria gracilis
[152][173] Melastoma malabathricum L. Melastomataceae Planter’s rhododendron or Sendudok Antibacterial Oceanapia sp.Malaysia G(+): Leaves B. subtilis Porifera (Demospongiae)

G(-): V. fischeri, V. cholerae, P. aeruginosaSalmonella sp., A. hydrophilaMeOH/H2O (4:1, v/
Disk diffusion method Chloramphenicol Kamagi Bay, Sada Peninsula, Japan MeOH extracts partitioned between ether and H2
Oceanapia sp.O. Organic phase partitioned between  Antibacterial

Antifungal
G(+):

B. subtilis, S. aureus

G(-): E. coli, P. aeruginosa

Yeast: S. cerevisiae, C. albicans (GT160-45C, cdc5, act1-1, YAT2296c)

Fungi: Penicillium chrysogenum, Mortierella ramannianan-hexane and MeOH/H
v), defatted with petroleum ether and extracted with CHCl3. Lipids recovered after elution of the CHCl3 extract by SiO2 column with CHClMIC: 5 µg/disk

IZ (mm)

B. subtilis 10.3–17.6 (CHCl33/acetone/MeOH (10:9:1, v/v).
)/10–15.6 (Et2Steryl glycoside:

β-sitosterol 3-O-β-D-glucopyranoside
[58]
Melastoma malabathricum L.O) [92][94]
2O (9:1, v[69]
S. aureus ATCC 25923, B. cereus ATCC 10876, /v). Aqueous MeOH fraction subjected to C18. Purification on SiO2 column (CHCl3, CHCl3/MeOH (9:1), CHCl3/MeOH/H2O (6:4:1), and MeOH) Acetylenic acid 1H and 13C NMR, FAB-MS, UV, IR Disk diffusion method   IZ (mm)

S. cerevisiae: 6.5–10

C. albicans: 8

E. coli: 8.5–12.0

P. aeruginosa: 8.5–13.0

B. subtilis: 11.0

S. aureus: 9.5–13.5[153][161]
[153][161] Azadirachta indica A. Juss Meliaceae Neem India Gracilariopsis longissima ParagrantiaAntibacterial, Antifungal  cf. waguensisLeaves G(+): S. agalactiae, Enterococcus sp.

G(-): P. aeruginosaV. salmonicidaV. fluvialis, V. vulnificus, V. cholerae non-O1, V. alginolyticus

Yeast: C. albicans, C. famataC. glabrataMeOH. Recovered after elution on a SiO
Disk diffusion method Porifera (Calcarea)
Paragrantia  Onna village, Okinawa, Japan  cf. waguensisMeOH extract partitioned between H Antibacterial G(+):

S. aureus (IAM 12084)

G(-): E. coli (ATCC 12600)2O and EtOAc. EtOAc extract subjected to Sephadex LH20 (CH2Cl2/MeOH, 1:1, v/2 column with CHCl3/MeOH (9:1, v/v)
IZ (mm)

V. alginolyticus: 25

V. fluvialisSQDG
: 8

V. vulnificus: 15

V. cholerae non-O-1:10[
v). Fraction separation on RP HPLC Acetylenic acid 1H and 13C NMR, ESI-MS, UV, IR Broth microdilution method Rifampicin, Nalidixic acid MIC (µg/mL)

S. aureus: 64

E. coli[93][108]59][71]
Azadirachta indica A. Juss
: 128[154][163]
[154][163] Neem India Hypnea musciformis, Osmundaria obtusiloba, Porphyra acanthophora, Pterocladiella capillaceaLeaves Petroleum ether (60–80 °C) for 24 h and extracted thrice with MeOH for 48 h each time at room temperature Antiviral Virus: HSV-1-ACVs, HSV-1-ACVr Titer reduction   PI(%)/VII

Petrosia weinbergi Porifera (Demospongiae) Acklin Island, Bahamas MeOH/CHCl3 (1:1, v/v). Aqueous suspension extracted with EtOAc, EtOAc/n-BuOH (1:1), and n-BuOH. Active extracts fractionated by C18 HPLCO. obtusiloba

Steroid sulfates

(Weinbersterol disulfates)ACVs-HSV-1: 82.2–99.5/0.75–2.35

Petrosia weinbergiSQDG [60][72]
HSV-1-ACVr: 99.7–99.9/2.5–4.5 Antiviral Viruses: Feline leukemia virus (FeLV), HIV  1H and 13C NMR, FAB-MS, IR[81][97]
  EC50 (µg/mL)

[155][166] Carapa guianensis Aubl. and Carapa vasquezii Kenfack Andiroba Brazil Seed oil Jania corniculata, Laurencia papillosan-hexane with Soxhlet extractor Antibacterial, Antifungal G(+): B. subtilis, Staphylococcus albus, E. faecalis

G(-): E. coli

Yeast: C. albicans

Fungus: A. flavusFA, FAME, squalene, 
Disk diffusion methodβ-sitosterol   11 < IZ ≤ 15

No IZ (A. flavus)[42][58]
[94][93] Ficus lutea Vahl Moraceae Giant-leaved fig or Lagos rubbertree Cameroon Woods CH2
Laurencia okamurai Antifungal Yeast: C.

neoformans (32609), C. glabrata (537)

Fungi: Trichophyton rubrum (Cmccftla), A. fumigatus (07544)
Cl2/MeOH (1:1,  Broth dilution methodv/v) and elution with EtOAc/10% MeOH Amphotericin B, fluconazole, voriconazole, ketoconazole MIC80 (µg/mL)

C. neoformans: 8–64

C. glabrata: 4–64

A. fumigatus: >64

T. rubrum: 64Glycosphingolipid [1-O-β-D-glucopyranosyl-(2
[95S,3][109R,5E,12E)-2N-[(2′R)-hydroxyhexadecanoyl]-octadecasphinga-5,12-dienine] named lutaoside ][61][76]
Ficus pandurata Hance Fiddle leaf fig
LaurenciaEgypt  spp. Antibacterial G(-): Chromobacterium violaceum, P. mirabilis,

P. vulgaris, ErwiniaFruits
 sp.,

70% MeOH. MeOH extract fractionated on a SiO2 column and purified by semi-preparative HPLC to afford pure ceramides
Ceramides [panduramides A-D, and newbouldiamide] V. parahaemolyticus, V. alginolyticus Disk diffusion method   MIC (µg/disk)

C. violaceum: 10–40

P. mirabilis: 20–40

P. vulgaris: 20–40

Erwinia sp.: 10–30

V. parahaemolyticus: 20–40

V. alginolyticus: 20–30[62][75]
[96][110] Kunzea ericoides (A. Rich) J. Thompson Myrtaceae Kanuka

(Maori), white manuka (Maori) or the white tea tree

(English)
Australia Leaves and twigs CH2Cl2:MeOH (1:1, v/v), CH2Cl2:MeOH (2:1, v/v) and CH2Cl2 (neat) Steryl esters, triacylglycerols, free FA, sterols, and phospholipids [63][77]
Osmundaria obtusiloba Antiviral Virus: HSV-1, HSV-2 Titer reduction Acyclovir EC50 (µg/mL)/SI/PI(%)

HSV-1: 42/1.7/75

HSV-2: 12/6/96
[97][111] Pentagonia gigantifolia Ducke Rubiaceae  
Palmaria palmata, Grateloupia turuturu AntibacterialPeru G(-): V. harveyiRoots  ORM4 Broth microdilution method95% EtOH. EtOH extract was fractionated on a SiO2 column using CHCl3/MeOH from 0% to 100% MeOH. Fraction eluted with 2% MeOH/CHCl3 was separated on C18 SiO  2 using 85% to 90% MeOH. Acetylenic acids: 6-octadecynoic acid and 6-nonadecynoic acid 0.2 < PI ≤ 7.9% [98][112[64][38]
] Hedyotis pilulifera (Pit.) T.N. Ninh   Vietnam , Aerial parts MeOH at 60 °C, suspended in water and successively partitioned with CHCl3 and EtOAc. EtOAc extract fractionated on a SiO2 column. Triterpenoids, steroids, FA, glycolipids, and a ceramide n-hexane. Soxhlet extractor. [65][83]
n-hexane extract fractionated on SiO2 column (2, 10, 20, 30 and 100% acetone) Phospholipids (main compounds PC-O, PE, PS, PI, SM, GlCer), Glycolipids (MGDG), Triacylglycerol, DAG LC-ESI-MS/MS
Pyropia orbicularis Antibacterial G( + ): S. aureus, B. cereus

G(-): E. coli
[ Disk diffusion method99][ Kanamycin113] 16 < IZ < 26 [99][113] Withania somnifera (L.) Dunal, Euphorbia hirta L., Terminalia chebula Retz.
Sphaerococcus coronopifolius Atlantic coast of Morocco MeOH/CH2Cl2. Extract separated on SiO2 column (hexane, gradients of hexane/CH2Cl2 and CH2
Sphaerococcus coronopifoliusCl2/acetone, and MeOH) Bromoditerpenes (Sphaerolabdadiene-3,14-diol (1), Sphaerococcenol) 1 Antibacterial, AntiplasmodialH and  G(+): S. aureus (ATCC # 6538)

Parasitic protozoa: P. falsciparum13C NMR, HRMS, EIMS, CIMS, FTIR, UV
 (FCB1)[100][114]
Antibacterial: Disk-diffusion, Antimalarial: inhibition of [3H]-hypoxanthine uptake by P. falsciparum cultured in human blood Macroalgae–Ochrophyta
  S. aureus-MIC: 0.104–0–146 µM

P. falciparum-IC50: 1 µM [100][114] Dictyota cervicornis, Dictyota menstrualis
Macroalgae–Ochrophyta
Dictyota cervicornis, Dictyota menstrualis Antiviral Virus: HSV-1-ACVs, HSV-1-ACVr Titer reduction     [81][97]
Dictyota fasciola, Taonia atomaria Antibacterial, Antifungal, Antiviral G(+): B. subtilis

G(-): E. coli

Fungi: C. albicans, A. niger

Virus: HSV-1
Disk diffusion method (antibacterial); Plaque reduction assay (antiviral)   D. fasciola:

Inhibition (%)

HSV-1: 50.00–81.25%

T. atomaria: MIC (µm/mL)/IZ(mm)

B. subtilis: 80/9, E. coli: 80/7, C. albicans: 80/10,

A. niger: 60/12

Inhibition (%)

HSV-1: 31.25–34.37%
[87][103]
Antibacterial, Antiviral G(+):B. subtilis NRRL B-94

G(-): E. coli NRRL B-3703

Virus: HSV-1
Disk diffusion method (antibacterial); Plaque reduction assay (antiviral) Chloramphenicol (bacteria), Acyclovir (virus) MIC (µg/mL)/IZ (mm)

PI(%)

D. fasciola

E. coli: -/8

B. subtilis: -/10

HSV-1: 46.87–70.12%

T. atomaria:

E. coli: 60/15

B. subtilis: 40/13

HSV-1: 43.75–56.25%
[75][89]
Fucus evanescens Antibacterial G(+): B. cereus, Clostridium difficile, MRSA, Propionibacterium acnes (ATCC and clinical isolate), 
FeLV: 4.0–5.2

HIV: 1.0 [155][166] Poecillastra wondoensis, Rhabdastrella wondoensis

(two-sponge association)
Porifera (Demospongiae) Cheju Island, South Korea MeOH (70%). Extract partitioned with Et2O and H2O. Aqueous phase extracted with n-BuOH, subjected to C18 flash chromatography and Sephadex LH-20. Purification on C18 HPLC Steroidal glycosides

(Wondosterols)
1H and 13C NMR, FAB-MS, UV, IR [156][175]
Poecillastra wondoensis, Rhabdastrella wondoensis

(two-sponge association)
Antibacterial G(-): P. aeruginosa,

E. coli
Disk diffusion method   Active concentration 10 µg/disk [156][175] Pseudoceratina purpurea Porifera (Demospongiae) Kaunakakai Harbor, O’ahu island, Hawaii, USA EtOH and methylene chloride. Combined extracts partitioned (hexane, methylene chloride and BuOH) Isolation: SiO2 flash column (hexane). Purification: Sephadex LH-20 Bromotyramine homoserine-derived (Mololipids) 1H and 13C NMR, HR-FAB-MS, UV, IR
Pseudoceratina purpurea Antiviral[ Virus: HIV-1157]  [191] S. pyogenes

G(-): Acinetobacter baumannii, E. coli, Haemophilus influenzae, K. pneumoniae, Legionella pneumophila, P. aeruginosa
Disk diffusion method   MIC100
  EC50 (µM): 52.2 [157][191] Axinyssa digitata Porifera (Demospongiae) Tunisia Acetone extract partitioned between H2O and Et2O. Aqueous residue re-extracted with n-BuOH and chromatographed on Sephadex LH-20 column (MeOH) and C18 HPLC Buzios, Rio de Janeiro, Brazil Acetone insoluble material extracted with CHCl3/MeOH (2:1 and 1:2, v/v). Extract partitioned on SiO2 column (CHCl3, acetone or MeOH) Glycolipid-rich extracts (Sulfoglycolipids, Glycosyldiacylglycerols) HPTLC [81][97]
Dictyota fasciola, Taonia atomaria Mediterranean Sea, Egypt CHCl3/MeOH (2:1, v/v). Glycolipid separation using acetone on SiO2 column Glycolipid-rich extracts (DGDG) GC-FID, LC-MS/MS [103]


V. ordalii: 8–1287] Mediterranean Sea, Egypt MeOH/CHCl3 (2:1, v/v). Sulfolipid isolation: diethylaminoethyl-cellulose column (CHCl3/MeOH (6:4, v/v) and NH3) Glycolipids (Sulfolipids) GC-MS, GC-FID, LC-MS/MS, IR [75][89]
Fucus evanescens West coast of Ungava Bay, Canada EtOAc (99%), CH2Cl2. EtOAc algal extract acetylated and organic layer purified by flash chromatography (0% → 50% EtOAc in hexane and flushed with 100% EtOAc and 5% MeOH in 95% EtOAc) Glycolipid-rich extracts 1H and 13C NMR [101][115]


[: 50 µg/mL [101][115]
Steroid sulfates

(Halistanol sulfates)
Axinyssa digitata Antiviral1 Viruses: HIV-1, HIV-2H and 13C NMR, FAB-MS     Himanthalia elongata Las Palmas, Spain Pressurized liquid extraction Hexane, EtOH, H2O Sterol (Fucosterol), FA GC-MS, HPLC-DAD Himanthalia elongata Antibacterial G(+): S. aureus ATCC 25923,

G(-): E. coli ATCC 11775

Yeast: C. albicans ATCC 60193

Fungi: A. niger ATCC 16404[102][116]
Broth microdilution method   MBC (mg/mL)

S. aureus: 6.25

E. coli: 6.00

MFC (mg/mL)

C. albicans: 8

A. niger: 12
[102][116] Laminaria cichorioides Khasan region of the Primorskii Territory, in the Troitsa Gulf (the Sea of Japan), Russia
Laminaria cichorioidesEtOH (96%). Lipophilic fraction extracted with CHCl3 Antibacterial, Antifungal. Fractionation of lipid classes on SiO2 column Glycolipids (MGDG, DGDG, SQDG), Free FA, PUFA G(+): S. aureus ATCC 21027

 
G(-): E. coli ATCC 15034

Yeast: Safale S04, C. albicans KMM 455

Fungi: A. niger KMM 4634, F. oxysporum KMM 4639[
Disk diffusion method77] Fucoxanthin, Nitrofungin[91]
IZ (mm)

S. aureus: 2–5

E. coli:1–6 Sargassum dentifolium Suez Canal, Egypt EtOH (70%), CH2Cl2 FA GC-MS [94][93]
Sargassum fusiforme, Sargassum vulgare Red Sea, Egypt Et2O, MeOH, EtOH, CHCl3 Terpenoids, FA GC-MS [103][117]
Sargassum pallidum Trinity Bay in the Peter the Great Gulf, Russia EtOH; EtOH/acetone (1:1, v/v), EtOH/CHCl3 (1:1, v/v). Fractionation of lipid classes on SiO2 column (hexane, Et2O/hexane with increasing ether concentration (95:5 → 50:50, v/v) and CHCl3) Glycolipids (MGDG, SQDG; DGDG), Free FA/Esters, Triacylglycerols, DAG   [104][118]


C. albicans: 1–6

A. niger: 1–3

F. oxysporum: 1–4
[77][91]
Sargassum dentifolium Antibacterial, Antifungal G(+): B. subtilis, S. albus, E. faecalis

G(-): E. coli

Yeast: C. albicans

Fungus: A. flavus
Disk diffusion method   11 < IZ (mm) ≤ 12

No IZ (A. flavus)
[94][93]
Sargassum fusiforme, Sargassum vulgare Antibacterial Multidrug resistant:

S. aureus,

P. aeruginosa,

Shigella flexneri,

E. coli,

Corynebacterium sp.
Agar well diffusion   9.33 < IZ (mm) ≤ 23.33

MIC: 50–100 mg/mL
[103][117]
Sargassum pallidum Antibacterial, Antifungal G(+): S. aureus ATCC 21027

G(-): E. coli ATCC 15034

Yeast: C. albicans KMM 455

Fungi: A. niger KMM 4634, F. oxysporum KMM 4639, Septoria glycines
Agar well diffusion   IZ (mm)

S. aureus: 0.7–14.5

E. coli: 0.5–6.7

C. albicans: 1.0–4.5

A. niger: 2.0–5.7

F. oxysporum: 1.0–5.2

S. glycines: 2.0–5.7
[104][118]
Sargassum vulgare Antiviral Virus: HSV-1, HSV-2 Titer reduction Acyclovir PI (%)

HSV-1: 96.0–99.9

HSV-2: 99.9
[105][119]
Sargassum wightii Antibacterial Xanthomonas oryzae pv. oryzae CAS ar01 Disk diffusion method   IZ (mm): 3.0–13.5 [106][120]
Microalgae
Chaetoceros muelleri Antibacterial, Antifungal G(+): Staphyloccocus aureus (ATCC 25923)

G(-):E. coli (ATCC 11775)

Yeast: C. albicans (ATCC 60193)
Broth microdilution method Chloramphenicol, Amphotericin B MBC (mg/mL)

E. coli: 12–15

S. aureus: 12–17

C. albicans: 7–9
[107][121]
Chlorococcum HS-101 Antibacterial G(+): MRSA, S. aureus ATCC 25923 Disk diffusion method Gentamicin, Amikacin, Cephalosporin, Habekacin, Ampicillin, Vancomycin, Oxytetracyclin, Erythromycin, Cefmetazole, Fosfomycin, Imipenem, Minomycin IZ (mm): 18.7–28.3 [108][122]
Dunaliella salina Antibacterial, Antifungal G(+): S. aureus ATCC 25923

G(-): E. coli ATCC 11775

Yeast: C. albicans ATCC 60193

Fungi: A. niger ATCC 16404
Disk diffusion method Chloramphenicol (bacteria),

Amphotericin B (yeast and fungi)
MBC (mg/mL)

E. coli: 6–30

S. aureus: 8–30

MFC (mg/mL)

C. albicans: 12–30

A. niger: 32–>35
[109][123]
Navicula delognei f. elliptica Antibacterial G(+): Staphyloccus aureus (ATCC 25923), S. epidermidis (ATCC 12228)

G(-): S. typhimurium (ATCC 14028), P. vulgaris (ATCC 13315), Enterobacter cloacae (ATCC 23355), E. coli (ATCC 25922), K. pneumoniae (ATCC 13883), Serratia marcescens (ATCC 8100)
Disk diffusion method Ampicillin, Tetracycline, Chloramphenicol IZ (mm)

S. aureus >4

S. typhimurium >4

S. epidermidis >2

P. vulgaris >2

E. coli IZ noticeable

No IZ (E. cloacae, K. pneumoniae, S. marcescens)
[110][124]
Phaeodactylum tricornutum Antibacterial, Antifungal G(+):

S. aureus

(SH1000), Bacillus weihenstephanensis

(10390), MRSA 252, MRSA 16a, S.

epidermidis, M. luteus (NCIMB 9278), Planococcus citreus

(NCIMB 1493), B. cereus (883-00)

G(-): Alteromonas

haloplanktis (NCIMB 19), A. hydrophila

(NCIMB 1108), Photobacterium

phosphoreum (NCIMB 64), Psychrobacter immobilis (NCIMB 308), Listonella anguillarum

(MT1637),

E. coli B,

P. aeruginosa (NCIMB 10775)

Yeast: C. glabrata, Candida neoformis,

Candida sp., Saccharomyces cerevisiae BY4741a
Disk diffusion method Ampicillin IC50 (µM)/MBC (µM)

S. aureus: 10–40/40–80
[111][125]
Antibacterial, Antifungal G(+):M. luteus (NCIMB 9278), Planococcus

citreus (NCIMB 1493), B. cereus (883-00), S. aureus (SH1000), B. weihenstephanensis (10390), MRSA 252, MRSA16a, S. epidermidis

G(-): Alteromonas haloplanktis (NCIMB 19), A. hydrophila (NCIMB 1108), Photobacterium phosphoreum (NCIMB 64), Psychrobacter immobilis (NCIMB308), Listonella anguillarum (MT1637), E. coli B, P. aeruginosa (NCIMB 10775)

Yeast:C. glabrata, C. neoformis, Candida sp., S. cerevisiae BY4741a
Agar well diffusion   Growth inhibition (mm2)

≤50–>50

S. aureus: 25–190 mm2
[112][126]
Synechocystis sp. Antibacterial G(+): S. aureus ATCC 25923

G(+): E. coli ATCC 11775,

Yeast: C. albicans ATCC 60193

Fungi: A. niger ATCC 16404
Broth microdilution method   MBC (mg/mL)

S. aureus: 7

E. coli: 5.6

MFC (mg/mL)

C. albicans: 12

A. niger: 14
[102][116]
Abbreviations: CC: cytotoxic concentration; EC: effective concentration; HSV: herpes simplex virus; IC: inhibitory concentration; IZ: inhibition zone; MIC: minimum inhibitory concentration; MBC: minimum bactericidal concentration; MFC: minimum fungicidal concentration; MRSA: methycillin-resistant Staphylococcus aureus; PI: percentage of inhibition; SI: selectivity index; TI: therapeutic index; VII: viral inhibition index.
Several studies have tested the antimicrobial activity of macroalgal extracts obtained with different solvents. Shanab (2007) compared extracts from three macroalgae species (Sargassum dentifoliumLaurencia papillosa, and Jania corniculata) using two solvents, EtOH and CH2Cl2 [94][93]. Both extracts exhibited similar antimicrobial activity against all microorganisms tested (bacteria and yeasts), except against the mold Aspergillus flavus [94][93]. Several extracts from Gracilaria gracilis were studied to identify potential bioactive compounds [92][94]. CHCl3 and Et2O extracts (apolar solvents) presented lower extraction yields (% of dry algal biomass) than extracts from more polar solvents (EtOH, MeOH, and acetone). Less polar solvents isolated minor lipid classes (e.g., neutral and medium polar lipids) and showed lower amounts of soluble carbohydrates and total phenols than polar solvents. However, the diameter of the inhibition zones against B. subtilis were slightly lower in these extracts than in the extracts obtained with polar solvents (rich in soluble carbohydrates and phenolic compounds) [92][94]. These results suggest that although less polar solvents have lower yields, they contain compounds with interesting antibacterial features.
The lipids or lipid mixtures, their extracting solvent(s), and the methods used for their characterization in algae species are summarized in Table 3. The results of the antimicrobial assays with lipids and lipid-rich extracts from these algae are summarized in Table 4. Chemical structures of lipids isolated from algae are represented in Figure 12.

3.2. Marine Invertebrates

The chemotaxonomic diversity of marine invertebrates is responsible for the large number of novel compounds identified in their phyla. Tropical biodiversity-rich benthic communities have been the most explored, thus the most fruitful in the identification of new potential antimicrobial compounds [113][114][115][137,138,139]. However, less conventional environments such as the Arctic ocean or mesopelagic communities have been started to be surveyed [116][117][140,141].
Marine invertebrates comprise a growing source of natural compounds, showing novel structures for biomedical and health-promoting applications [118][142]. Bioprospection of new compounds from marine invertebrates has revealed to be a prolific work to discover diverse bioactive compounds with action toward a broad spectrum of microorganisms [116][119][140,143]. Some of these reports have identified total lipid extracts as a potential source of bioactive compounds, lacking a sequential workflow of isolation, characterization, and purification of the metabolites responsible for the activity [83][119][99,143]. Although most of these studies used classical bioprospection methods to identify the bioactive compounds from marine species, others followed eco-friendly approaches by using fishing waste [117][141] or seafood by-products [120][144].
Phyla of marine invertebrates recognized as sources of antimicrobial compounds [16][121][16,145] include porifera [122][123][146,147], crustacean [124][125][148,149], mollusk [120][126][127][144,150,151], or cnidaria [113][115][137,139]. Some bacteria isolated from marine organisms have also disclosed antibacterial activity, such as Actinobacteria from sponges [26].
The main antibacterial natural products identified in marine invertebrates were peptides, polyketides, alkaloids, terpenes, and lipopeptides [14][128][126][129][14,34,150,152]. However, several antimicrobial lipids classes have been identified. Marine invertebrates produce an array of unique lipids originating from unusual biosynthetic pathways that are not common in other environments, as a result of thriving in diverse and extreme environments [118][130][142,153].
Porifera represents the most studied phylum of marine invertebrates for antimicrobial compounds’ bioprospection, including lipids [131][132][154,155]. The high contribution of these ancestral metazoans for bioactive compounds’ research seems to be related to their high filtering activity, pumping water during feeding, which expose them to viruses, bacteria, and eukaryotic organisms (pathogenic and non-pathogenic) [133][134][156,157].
Table 5 assembles the information regarding lipids from marine invertebrate species having antimicrobial activity. Table 6
EC
50
 (µg/mL)


HIV-1: 3–6


HIV-2: Not referred
[
158
]
[
165
]
[
158
]
[
165
]
Siliquariaspongia
 sp.
Porifera (Demospongiae)
Motualevu reef, Fiji
Siliquariaspongia sp. Antibacterial G(+):

S. aureus, MRSA
H2O and MeOH/CH2Cl2 (1:1, v/v). n-BuOH-soluble material from the aqueous extract and CHCl3-soluble material from the organic extract chromatographed on Sephadex LH-20 (MeOH/H2O, 3:1, v/v). Purification by RP HPLC Brominated long-chain acids (Motualevic acids) Disk diffusion method, Microbroth dilution  1H- and  MIC5013C-NMR, LC-MS, HR-ESI-MS, FT-IR  (µg/mL)

S. aureus: 1.2–10.9

S. aureus (MRSA):

3.9–400[159][164]
[159][164] Siphonodictyon coralliphagum Porifera (Demospongiae) Lighthouse Reef and Glover Reef, Belize
Siphonodictyon coralliphagum Antibacterial G(+): S. aureus,

EtOH. Aqueous suspension extracted with CH2Cl2, EtOAc and n-BuOH. EtOAc extract fractionated by chromatography and purified on SiO2 plates B. subtilisPhenolic aldehydes

(Siphonodictyal)
1H and 13C NMR, IR, UV  [  160] Active against S. aureus, B. subtilis[182]
[160][182] Spheciospongia purpurea Porifera (Demospongiae) Weizhou Island, Guangxi Autonomous Region, China
Spheciospongia purpurea Antifungal Yeasts: C. neoformans (32609), C. glabrata (537)

Fungi: T. rubrum (Cmccftla), A. fumigatus (07544),
Acetone. Extract resuspended in H2O and partitioned with Et2O. Et2O extract fractionated on SiO2 (petroleum ether/acetone, 1:0 → 0:1), Sephadex LH-20 (CH2Cl2/MeOH, 1:1). Purification by C18 HPLC Lysophospholipids

(PAF(16:0), PAF (16:1 n-5), PAF (18:0), PAF (18:1 n-7), PAF (18:1 n-11), PAF (18:1 n-13))
1H and  Broth dilution13C NMR, IR, ESI-MS, HR-ESI-MS, LC-MS/MS Amphotericin B, Fluconazole, Voriconazole, Ketoconazole MIC80 (µg/mL)

C. neoformans: 4–32

C. glabrata: 8–64

A. fumigatus: >64

T. rubrum: >64[122][146]
[122][146] Family Spongiidae
Family SpongiidaePorifera (Demospongiae) Antibacterial

Unten Port, Okinawa, Japan
Antifungal G(+): B. subtilis, M. luteus, S. aureus

G(-): E. coli

Yeasts: C. albicans, C. neoformans

Fungi: A. nigerMeOH extract partitioned between EtOAc and H2O. H2O-soluble portions extracted with n-BuOH. EtOAc and n-BuOH, soluble materials purified by SiO2 columns and C18 HPLC
 Sesquiterpenoid

(Sesquiterpenoid quinones, Nakijiquinones)
1H and 13C NMR, FAB-MS, UV, IR   MIC (µm/mL)

B. subtilis: 33.3

E. coli: >33.3

M. luteus: 16.7–33.3

S. aureus: 33.3

C. neoformans: 8.35

C. albicans: 8.35

[161][185]
A. niger: 16.7 [161][185] Suberites domuncula Porifera (Demospongiae) Rovinj, Croatia
Suberites domuncula Antibacterial Bacterium SB1 (strain isolated from S. domuncula with >98.0% similarity to the alpha-Proteobacterium (MBIC3368)MeOH and CHCl3. Combined extracts partitioned between H2O and BuOH. Organic layer fractionated by medium-pressure on C18 (linear gradient H2O → MeOH → CHCl3). Purification by RP HPLC Lysophospholipids

(PAF)
1H NMR, FIA-MS, LC-MS/MS [134][157]
Disk diffusion method   IZ (mm): 4.5–6.8 [134][157] Topsentia sp. Porifera (Demospongiae) Chuuk, Federated States of Micronesia
Topsentia sp. Antifungal G(+):MRSA,

Acid-fast bacterium: M. intracellulare

Parasitic protozoa: P. falciparum (D6 and W2 clones),

L. donovani

Yeasts: C. albicans, C. glabrata, Candida krusei, S. cerevisiae, C. neoformans

Fungus: 
CH2Cl2/MeOH (1:1, v/v). Extract fractionated by SPE using C18 cartridges A. fumigatusSteroid sulfates

(Eurysterols)
1H and  Broth microdilution method13C NMR, HR-ESI-MS, IR, UV Beauvericin FIC (µM)

C. albicans: 0.2–1.8

S. cerevisiae: 0.08–1.34[162][168]
[162][168] Xestospongia sp. Porifera (Demospongiae) Rasch Pass of Madang, Papua New Guinea Hexane, CH2Cl
Xestospongia sp.2 Antibacterial G(+): MRSA, S. mutans, S. sobrinus and EtOAc. Hexane extract subjected to flash column (gradient hexane/EtOAc (95:5, v/v) → EtOAc) Brominated FA Disk diffusion method1H and 13C NMR, IR, UV, HR-EI-MS, HR-APCI-MS, HR-FAB-MS   IZ (mm)

MRSA: 12

S. mutans: 17

S. sobrinus: 14[114][138]
[114][138] Hyas araneus,

Podopthalmus vigil,

Lauridromia dehanni, Charybdis helleri, Portunus sanguinolentus,

Portunus pelagicus
Arthropoda (Malacostraca) Vellar Estuary, India MeOH Lysoglycerolipids/glycerides

FA/esters
Hyas araneus, Podopthalmus vigil, Lauridromia dehanni, Charybdis helleri, Portunus sanguinolentus, Portunus pelagicus Antibacterial

Antifungal
G(+): S. aureus, MRSA, S. pyogenes

G(-): E. coliP. aeruginosa, S. typhiS. flexneriKlebsiella sp., V. choleraeAcinetobacter sp.

Yeasts: Rhodotorula

sp., C. albicansC. neoformans

Fungi: A. fumigatus
1H and 13C NMR, ESI-MS/MS, FT-IR A. niger Disk diffusion method Penicillin, Ketoconazole IZ (mm)

S. pyogenes: 1

S. typhi: 1–3

S. flexneri: 1–6

V. cholerae: 1–4

Acinetobacter sp.: 1[124][148]
[124][148] Meganyctiphanes norvegica Arthropoda (Malacostraca) Straits of Messina, central Mediterranean Sea, Italy H2O/acetone (1:1, v/v). Supernatant recovered with CH₂Cl₂. Extracts fractionated by semi-preparative RP HPLC-DAD on SB-C8 column FA

(EPA, DHA, ETA)
LC-MS, HPLC-UV-HR-MS [
Meganyctiphanes norvegica117] Antibacterial[141]
G(+): MRSA, MB5393, MSSA, ATCC 29213

G(-): E. coli (ATCC 25922), K. pneumoniae (ATCC 700603)

Acid-fast bacterium: M. tuberculosis (H37Ra ATCC 25177)
Well plate, REMA method Vancomycin hydrochloride, Aztreonam, Gentamycin sulfate MIC (µg/mL)

MRSA: 80–320

MSSA: 320

M. tuberculosis: 320
[117][141] Aplidium sp. Chordata (Ascidiacea) Northland, New Zealand MeOH-CH
Aplidium sp. Antibacterial

Antiviral

Antifungal
G(+): B. subtilis

Fungi: T. mentagrophytes
2Cl2 extract fractionated with RF C18 flash column (MeOH/H2O), Sephadex LH20 (MeOH), semi-preparative C18 HPLC Meroterpene derivatives

(Rossinones)
1H and 13C NMR, HR-FAB-MS, UV, IR [163][189]


Virus: HSV-1 Disk diffusion method   Eunicea succinea Cnidaria (Anthozoa) Mona Island, Puerto Rico, CHCl3/MeOH (1:1, v/v). Extract fractionated by SiO2 column chromatography FA

((5Z,9Z)-14-methyl-5,9-pentadecadienoic acid)
1H and 13C NMR, GC-MS, HR-MS, IR [113][137]
IZ (mm)

B. subtilis/T. mentagrophytes: 3–6

Antiviral activity at 2 μg/disk [163][189]
Eunicea succinea Antibacterial G(+): S. aureus (ATCC 25923), E. faecalis (ATCC 29212)

G(-): P. aeruginosa (ATCC 27853), E. coli (ATCC 25922)
Broth microdilution method   MIC (µmol/mL)/IC50 (µg/mL)

S. aureus: 0.24/36

E. faecalis: 0.16/<10
[ Lobophytum crassum Cnidaria (Anthozoa) Rameswaram, India Aqueous EtOH (95%), MeOH. Extract partitioned with H2O and EtOAc. EtOAc extract fractionated on SiO2 column (gradient hexane/EtOAc) Cembranoid diterpene

Ceramide
1H and 13C NMR, FAB-MS, IR [164][177]
113][137]
Lobophytum crassum Antibacterial G(+): S. epidermidis, B. subtilis, S. aureus

G(-): P. aeruginosa
Disk diffusion method Ampicillin IZ (mm)

S. epidermidis: 9.5–16.5

B. subtilis: 8.5–18.0

S. aureus: 9.0–19.5

P. aeruginosa: 9.0–14.0
[164][177] Antillogorgia elisabethae
Antillogorgia elisabethaeCnidaria (Anthozoa) Bahamas Antibacterial G(+): S. pyogenes (ATCC 19615), S. aureus (ATCC 25923), E. faecalis (ATCC 19433)

G(-): E. coli (ATCC 25933), P. aeruginosa (ATCC 27853)MeOH. Extract redissolved in EtOH/H2O (2:8, v/v). EtOH/H2O extract reextracted with EtOAc, SiO2 column (hexane, 0 → 100% EtOAc/hexane, 0 → 100% MeOH/EtOAc). Fractions subjected to RP HPLC (0 → 100% H2O/Acetonitrile)
Diterpenes

(Elisabethin)
1H, 13C NMR, HR-EI-MS, UV, IR Disk diffusion method   MIC (µg/mL)/IZ (mm)

S. pyogenes: 0.8–1.0/12–17

S. aureus: 2.0–2.3/8–11

E. faecalis: 3.2–3.8/8–9[165][192]
[165][192] Sinularia grandilobata,

Sinularia sp.
Cnidaria (Anthozoa) Andaman Islands, India
Sinularia grandilobata,

Sinularia sp.
Antibacterial

Antifungal
G(+): B. subtilis (MTCC 441), Bacillus pumilus (NCIM 2327)

G(-): E. coli

(MTCC 443), P. aeruginosa (MTCC 1688)

Yeast: C. albicans (MTCC 183)

Fungi: 
EtOH. Extract reextracted with EtOAc. Combined extracts fractionated on SiO2 column (gradient system hexane/EtOAc (100:0 → 0:100)) A. niger (MTCC 1344), Rhizopus oryzae (MTCC 1987)Sphingolipids Disk diffusion method

  IZ (mm)

B. subtilis: 11–18

B. pumilus: 11–16

E. coli: 11–17

P. aeruginosa: 11–17

C. albicans: 8–17

A. niger: 10–16

R. oryzae: 10–15
[115][139] Sargassum vulgare Sepetiba Bay, Brazil CHCl3/MeOH (2:1 and 1:2, v/v). Fractionated on SiO2 column (CHCl3, acetone and MeOH) Glycolipid-rich extracts (Sulfoglycolipids)
Holothuria scabra Antibacterial G(+): S. aureus (ATCC 6538), E. faecalis

G(-): P. aeruginosa (ATCC 8739), V. damsela, E. coli
1 Well-cut diffusion techniqueH and 13C NMR, ESI-MS-MS [105][  119]
AU

S. aureus: 1.2–2.8

E. faecalis: 1.7–3.2

P. aeruginosa1H and 13C NMR, FT-IR,
[120][144]
Saccostrea glomerata Mollusca

(Bivalvia)
Kovalam, Tamilnadu, India
Agelas oroides Antibacterial, Antiplasmodial Acid-fast bacterium: M. tuberculosis

Parasitic protozoa: P. falciparum,

Trypanosoma brucei rhodesiense,

T. cruzi, L. donovani

G(-): E. coli
Glycolipids 1H and 13C NMR, EI-MS [115][139]
Holothuria scabra Echinodermata (Echinozoa) Red Sea, Egypt EtOH (70%), MeOH, EtOAc and CHCl3/MeOH (2:1, v/v) Pigments

(Carotenoids)
HPLC-UV/VIS, GC-MS : 1.4–1.8

V. damsela: 1.6

E. coli: 1.2[166][193]
[166][193] Sargassum wightii Gulf of Mannar, India MeOH. Isolation on SiO Dosidicus gigas Mollusca (Cephalopoda) Hermosillo, Mexico
Dosidicus gigas2 column (hexane/EtOAc, EtOAc/MeOH). Purification on flash SiO Antibacterial

2 column (CHCl3/MeOH gradients)
Antifungal G(+): B. cereus (CCM 2010), Clostridium perfringens (CCM 4991), Listeria monocytogenes (CCM 4699), S. aureus subs. aureus (CCM 2461)

G(-): Haemophilus influenza (CCM 4456), K. pneumoniae (CCM 2318), S. enterica subs. entericaAcidified MeOH (MeOH/HCl, 99:1, v/v)
 (CCM 3807)

Yeasts: C. albicans (CCM 8186), C. glabrata (CCM 8270), C. tropicalis (CCM 8223)

Glycolipid (Sulfoglycerolipid, 1-O-palmitoyl-3-O(6′-sulfo-α-quinovopyranosyl)-glycerol)
1H and 13C NMR, IR Fungi: Pigments

(Ommochrome)[106]
Aspergillus clavatus, A. flavus, Aspergillus versicolor, Penicillium chrisogenum, Penicillium griseofulvum, Penicillium expansum[120]
Disk diffusion method   Inhibition (%)

B. cereus: 39.4

C. perfringens: 45.5

L. monocytogenes: 60.7

S. aureus subs. aureus: 57.8

H. influenza: 54.5

K. pneumoniae: 39.4

S. enterica subs. enterica: 93.9

C. albicans: 66.7

C. glabrata: 42.4

C. tropicalis: 33.3

A. clavatus: 48.4

A. flavus: 42.4

A. versicolor: 42.4

P. chrisogenum: 39.4

P. griseofulvum: 42.4

P. expansum: 48.5
[120][144] Microalgae
Hexane, EtOAc and MeOH. Purification on SiO
Saccostrea glomerata2 column (hexane/EtOAc and EtOAc/MeOH) Antibacterial

Antifungal
G(+): S. aureus

G(-): P. aeruginosaV. harveyiA. hydrophila, P. aeruginosa, Sterols [Cholesta-5,22-dien-3β-ol, Cholesterol, Ergosta-5,22-dien-3-ol, (3β,22E)-],

FA (6-Octadecenoic acid, Octadecanoic acid)
GC-MS, FT-IR V. harveyiV. parahaemolyticus

Yeast: C. albicans

Fungi: A. nigerA. flavusFusarium sp.

Virus: White spot syndrome virus (WSSV)
Disk diffusion method   IZ (mm)

P. aeruginosa: 4.1–16.0

V. harveyi: 3.8–14.9

A. hydrophila: 5.1–14.5

A. niger: No activity–High activity

C. albicans: No activity–High activity

Fusarium sp: No activity–High activity

Antiviral activity: PI < 91.85%[167][171]
Chaetoceros muelleri  
[167][171] Supercritical fluid extraction, EtOH (99.5%) Triacylglycerol, DAG, MAG, sterols (cholesterol), FA HPLC-ELSD, GC-FID [107][121]
Chlorococcum HS-101 Japan MeOH extract, partitioned with hexane. SiO2 column (MeOH/CHCl3 gradient). Active fraction recovered with MeOH/CHCl3 (5:95, v/v) FA 1H and 13C NMR, GC-MS [108][122]
Dunaliella salina Jerusalem, Israel Pressurized liquid extracts: hexane, petroleum ether, EtOH FA

Sesquiterpenoids (Neophytadiene), Diterpenoid (Phytol)
GC-MS [109][123]
Navicula delognei Lepreau Ledges, New Brunswick, Canada MeOH, CHCl3, extract chromatographed on SiO2 column (CHCl3 and CHCl3/MeOH) FA [(6Z,9Z,12Z,15Z)-hexadecatetraenoic acid, (6Z,9Z,12Z,15Z)-octadecatetraenoic acid), Ester ((E)-phytol (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate] 1H and 13C NMR, GC-MS [110][124]
Phaeodactylum tricornutum Experimental Phycology and Culture Collection of Algae at the University of Göttingen (Germany) EtOAc and MeOH extracts applied to SiO2 Sep Pak cartridges. EtOAc extract eluted with 10% step increases of hexane/EtOAc until 100% EtOAc. MeOH extract eluted with 10% step increases of EtOAc/MeOH until 100% MeOH Free FA (palmitoleic acid, HTA) 1H and 13C NMR, ESI-MS [111][125]
  MeOH/H2O (5:1, v/v). Extract redissolved in MeOH (70%) and fractioned on Sep Pak cartridge (MeOH (70%) followed by constant volumes of MeOH (5% steps → 100%)). Fractionated by RP HPLC FA (EPA) 1H NMR, ESI-MS [112][126]
Synechocystis sp. Las Palmas, Spain Pressurized liquid extraction: hexane, EtOH, H2O FA, Sesquiterpenoids (Neophytadiene) GC-MS, HPLC-DAD [102][116]
Abbreviations: AU: activity unit for the clear zone; EC: effective concentration; FIC: fractional inhibitory concentration; IZ: inhibition zone; MIC: minimum inhibitory concentration; PI: percentage inhibition.
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