Post-harvest diseases can be a huge problem for the tropical fruit sector. These fruits are generally consumed in natura; thus, their integrity and appearance directly affect commercialization and consumer desire. Anthracnose is caused by fungi of the genus Colletotrichum and affects tropical fruits, resulting in lesions that impair their appearance and consumption. Antifungals generally used to treat anthracnose can be harmful to human health, as well as to the environment. Therefore, essential oils (EO) have been investigated as natural biofungicides, successfully controlling anthracnose symptoms. The hydrophobicity, high volatility, and oxidative instability of essential oils limit their direct application; hence, these oils must be stabilized before food application. Distinct delivery systems have already been proposed to protect/stabilize EOs, and nanotechnology has recently reshaped the food application limits of EOs. This review presents robust data regarding nanotechnology application and EO antifungal properties, providing new perspectives to further improve the results already achieved in the treatment of anthracnose. Additionally, it evaluates the current scenario involving the application of EO directly or incorporated in films and coatings for anthracnose treatment in tropical fruits, which is of great importance, especially for those fruits intended for exportation that may have a prolonged shelf life.
1. Introductiçãon
A
ant
hracnose
is a serious post-harvest disease that affects varioué uma doença pós-colheita grave que afeta várias frutas tropica
l andis e subtropica
l fruits such asis, como banana, mang
o, papaya, and avocadoa, mamão e abacate [
1 ].
TheA infec
tion is caused by fungi of the genusção é causada por fungos do gênero Colletotrichum ,
mainly in the flowering stage of the fruits, remainingprincipalmente na fase de floração dos frutos, permanecendo latent
until development after harvest and extending during storage. Infection can cause an undesirablee até o desenvolvimento após a colheita e estendendo-se durante o armazenamento. A infecção pode causar aspecto visual
appearance, acindesejável, acelera
te fruit ripening, and, in more advanced stages, lead to fruit rot. These symptoms impair the comr o amadurecimento dos frutos e, em estágios mais avançados, levar ao apodrecimento dos frutos. Esses sintomas prejudicam a comercializa
tion andção e exporta
tion of fruits, restraining selling andção das frutas, inibindo a venda e o consum
ptiono [
2 ,
3 ].
InAlém addition to the economic and fruit impacts, thedos impactos econômicos e frutíferos, o gênero Colletotrichum gpode
nus may pose a risk to representar um risco para a saúde human
health, because the spea, pois as espécies
C. atramentum ,
C. graminicola ,
C. dematium, ande C. gloeosporioides hfora
ve been reported to cause km relatadas como causadoras de ceratomi
cosisose.
C. truncatum wasfoi erron
eouslyeamente associa
ted with five cases of ophthalmic infectiondo a cinco casos de infecções oftálmicas original
ly caused bymente causadas por C. dematium [
4 ].
This study revealed, at the time, theEsse estudo revelou, na época, a import
ance of usingância do uso de métodos molecular
methods toes para identif
y speicar as espécies. Recent
ly, the speciesemente, a espécie C. chlorophyti wasfoi found to beconsiderada respons
ible for mycotic kável por ceratit
is in an 82-year-old mane micótica em um homem de 82 anos [
5 ].
Synthetic fFungicid
es such as thas sintéticos como tiabendazol
e and e imazalil
are the main treatments used in the management of fruits tosão os principais tratamentos utilizados no manejo de frutas para minimiz
e the effects ofar os efeitos da infec
tionção [
1 ,
3].
HNo
wever, several phytopathogens are entanto, vários fitopatógenos são resist
ant to thentes ao tiabendazol
e. F. Os fungici
des can be harmful to human health, as accumulation in tissues can generatedas podem ser prejudiciais à saúde humana, pois o acúmulo nos tecidos pode gerar hepatotoxici
ty, adrenal gland toxicitydade, toxicidade da glândula adrenal, carcinogenici
tydade/mutagenici
ty, nephdade, nefrotoxici
ty, anddade e distúrbios metab
olic disorder. In addition, they can cause damage to the environment and affectólicos. Além disso, podem causar danos ao meio ambiente e afetar a biodiversi
ty. From the food market point of view, dade. Do ponto de vista do mercado de alimentos, os consum
ers are becoming averse to theidores estão se tornando avessos à presen
ce of synthetic additives. Thus, it isça de aditivos sintéticos. Assim, faz-se necess
ary to search for effective, safe, andária a busca por tratamentos eficazes, seguros e natura
l treatments that do not impact consumers’ health or the environment and, when possible, promote no change in theis que não afetem a saúde do consumidor ou o meio ambiente e, quando possível, não promovam alteração nas propriedades sensor
y properties of foodiais dos alimentos [
6 ,
7 ].
In thiNess
scenario, natural e cenário, fungicid
es are being applied as a tool foras naturais estão sendo aplicados como ferramenta de controle microbiol
ogical control and, therefore, for post-harvest diseases. The use ofógico e, portanto, de doenças pós-colheita. O uso de óleos essen
tial oils tociais para preven
t the spread ofir a propagação da infec
tion has been studied as a naturalção tem sido estudado como uma opção de fungicid
e optiona natural. Andrade
ande Vieira [
8 ],
for example, studied the effect of anisepor exemplo, estudaram o efeito do anis (
Pimpinella anisum ), tea tree (
Melaleuca alternifolia ),
lemongrasscapim-limão (
Cymbopogon citratus ),
minthortelã (
Mentha piperita ),
rosemaryalecrim (
Rosmarinus officinalis )
, and cinnamon e canela (
Cinnamomum zeylanicum)
por me
ssential oils throughio de testes in vivo (
direct application) andaplicação direta) e in vitro
tests to assess conidipara avaliar a germina
tion. The authors noticed ação dos conídios. Os autores notaram um efeito fungit
oxic andóxico e fungist
atic effect of most oils used in difático da maioria dos óleos usados em diferent
es concentra
tions. Another studyções. Outro estudo demonstr
ated throughou por meio de testes in vitro
tests the potento potencial us
e of cinnamono do óleo essen
tial oilcial de canela (
Cinnamomum zeylanicum o
ru Cinnamomum verum )
on myno crescimento micelial
growth and spor e na geminação de esporos de
twinning of C. acutatum isola
ted
fromo de kiwi.
In this study, cinnamon oil showedNeste estudo, o óleo de canela mostrou efeitos fungist
atic andáticos e fungicida
l effects at s em concentra
tions of 0.ções de 0,175 µL/mL
and 0.e 0,2 µL/mL, respectiv
elyamente [
9 ].
TheA direct application of EOs to the fruit surface becomes a challenge, due to theaplicação direta de OEs na superfície do fruto torna-se um desafio, devido à volatili
ty of EOdade dos OEs [
10 ].
Hence, it is common to applyAssim, é comum a aplicação de óleos essen
tial oils inciais em formula
tions of polymeric coatings for fruits, aiming to increase their shelf life. However, the high hydrophobicity of theseções de revestimentos poliméricos para frutas, visando aumentar sua vida útil. No entanto, a alta hidrofobicidade dessas subst
ances makes it difficult to achieve a homogeneousâncias dificulta a obtenção de uma dispers
ion and spreadability over the whole fruit surface when it is simply added to the coatingão e espalhabilidade homogênea em toda a superfície da fruta quando ela é simplesmente adicionada à formula
tion.
Ação do reliveryvestimento.
Um s
yistem
designed to protect and deliver the desireda de entrega projetado para proteger e entregar os compo
unds at the right time and place is a viable alstos desejados na hora e no lugar certo é uma alternati
ve to overcome the challenges of usingva viável para superar os desafios do uso de óleos essen
tial oils in fruits. In this sense, the application of EOs in the form ofciais em frutas. Nesse sentido, a aplicação de OEs na forma de emuls
ions is a strategy to improve their ões é uma estratégia para melhorar sua dispersibili
ty and dade e homogenei
tydade. Emuls
ions are systems in which two immiscible liquids are ões são sistemas nos quais dois líquidos imiscíveis são homogen
ized to form a mixture of spherical droplets (eizados para formar uma mistura de gotículas esféricas (fase dispers
ed phase) in a surrounding liquid (continuous phase). Thea) em um líquido circundante (fase contínua). Os óleos essen
tial oils are usuallyciais são geralmente incorpora
ted into coatings in the form of oil-in-water (o/w) emulsionsdos em revestimentos na forma de emulsões de óleo em água (o/a). Depend
ing on theendo da concentra
tion, ção, as emulsões conven
tional EO emulsions can generate changes in fruit color and flavor, in addition to leading to EO cionais de OE podem gerar alterações na cor e no sabor da fruta, além de levar à degrada
tion whenção do OE quando expos
ed to extreme environmental conditiontas a condições ambientais extremas (temperatur
ea, pH, ox
ygen, light, and moisturigênio, luz e umidade) [
11].
AnoOut
her drawback is the fast release of volatile compounds, which can impair their biological action on fruit preservationra desvantagem é a rápida liberação de compostos voláteis, o que pode prejudicar sua ação biológica na conservação dos frutos [
12 ].
WhenAo dealing withlidar com óleos essen
tial oils for coating or film fciais para revestimento ou formula
tion, ção de filme, as nanoemuls
ions have receivedões têm recebido atenção substan
tial attention in recent years due to their functional and physicochemical properties. Ncial nos últimos anos devido às suas propriedades físico-químicas e funcionais. As nanoemuls
ions areões são emuls
ions with a droplet radius ranging between 10 andões com raio de gota variando entre 10 e 100 nm,
which are moreque são mais resist
ant toentes à coalesc
ence and phase ência e à separa
tion whenção de fases quando compar
ed toadas às emulsões conven
tional emulsions. The droplet size is directly related to the color ofcionais. O tamanho da gota está diretamente relacionado à cor das nanoemuls
ions, which can vary fromões, que pode variar de transparent
to slightly cloudye a levemente turva [
13 ,
14 ].
Essential oil nanNanoemuls
ions applied in systems to extend food shelf life might improve the functionality of EOs by increasing the oil droplet surface area and, consequently, the contact area between the active agents and the food, enabling the use of smaller doses of essential oils [13,15]. In ões de óleos essenciais aplicadas em sistemas para prolongar a vida de prateleira de alimentos podem melhorar a funcionalidad
dition,e oil droplets on the nanoscale are capable of easily diffusing into the microorganisms’ cellular membrane and disrupting its organization, promoting cellular internal content leakage and cellular death, which considerably improves antimicrobial capacity.
Thdos OEs por aumentar a área de superfície das gotículas de óleo e, consequentemente, a área de contato entre
use o
f essential oil nanoemulsions in active films and coatings is a promising alternative to increase the shelf life of anthracnose-susceptible tropical fruits. The performance of different essential oil emulsions in reducing deterioration levels depends on the chemical composition and the emulsion properties. To the best of our knowledge, this is the first review to focuss princípios ativos e o alimento, possibilitando o uso de doses menores de óleos essenciais.13 on, current15 trends]. related to the production of emulsions, especially nanoemulsions, involved in the development of active films and coatings for the preservation of tropical and subtropical fruits against the effects of infection by the genus Colletotrichum. IAlém disso, gotículas de óleo em nanoescala são capazes de se difun
thdi
s context, three main topics are investigated: (a) the characteristics of the fungus and the disease that can lead to tropical fruit degradation during storage and, consequently, to significant economic losses; (b) the characteristics of essential oils and their mechanism of action that makes them potential natural food additives for fruits; (c) the use of conventional and nanoemulsions in edible films/coatings for inhibition of fungal growth and consequent prevention of anthracnose symptomsr facilmente na membrana celular do microrganismo e desorganizar sua organização, promovendo vazamento do conteúdo interno celular e morte celular, o que melhora consideravelmente a capacidade antimicrobiana.
2. Anthracnose inem Frutos Tropical Fruitis
2.1. Dados Economic Data
Tômicos
Frutas tropica
lis ande subtropica
l fruits are widelyis são amplamente consum
ed worldwide; therefore, theidas em todo o mundo; portanto, a quali
ty and dade e diversi
ty of these fruits must bedade dessas frutas devem ser preserv
ed. The three main tropical fruit-producing countries areadas. Os três principais países produtores de frutas tropicais são China,
India, and Brazil. Brazil, despite beingÍndia e Brasil. O Brasil, apesar de ser respons
ible for the third largest fruit production in the world, has a smallável pela terceira maior produção de frutas do mundo, tem uma pequena representati
on in world fruitvidade nos patamares mundiais de export
levels. Only approximately three percent of its fruitação de frutas. Apenas cerca de três por cento de sua produ
ction was ção de frutas foi export
ed inada em 2021.
The failure to strengthenO não fortalecimento de acordos interna
tional agreements that have strict standards of comcionais que possuem padrões rígidos de comercializa
tion is the main factor ção é o principal fator que contribu
ting to the lowi para os baixos níveis de exporta
tion levels. Comção. A fruticultura comercial
fruit growing increasingly requireexige cada vez mais prof
eissionalism
and specific regulation, and fungalo e regulamentação específica, e a contamina
tion can directly affect this comção fúngica pode afetar diretamente esse sistema comercial
system. The low. O baixo volume export
ed volume is related, among other causes, to thado está relacionado, entre outras causas, à perda de quali
ty loss during storage anddade durante o armazenamento e transport
, which maye, o que pode result
in the nonacceptance of fruits by thear na não aceitação das frutas pelos países import
ing countries. Many of theseadores. Muitas dessas frutas tropica
l andis e subtropica
l fruits areis são susce
ptible totíveis à contamina
tion by species of ção por espécies deColletotrichum [
16 ,
17 ].
Fruit
As losspe
s are related to the decrease in the amount of food available for humanrdas de frutas estão relacionadas à diminuição da quantidade de alimentos disponíveis para consum
ption in tho humano nas fases de produ
ction, post-harvest, storage, andção, pós-colheita, armazenamento e transport
phases. According to thee. Segundo a FAO [
18 ], 14%
of the world’s food is lost after harvesting and before reaching retaildos alimentos do mundo são perdidos após a colheita e antes de chegarem ao varejo. Udayanga et al. [
19] re
polatar
ted that a largam que grande part
of the fruits grown in countries in the Asian region are lost due to improper handling, inefe das frutas cultivadas em países da região asiática se perde devido ao manuseio inadequado, transporte ineficient
transport, and fungal and bacterial contamination. The trade and export of these fruite e contaminação por fungos e bactérias. A comercialização e exportação dessas frutas depend
on the compliance with strict phytosanitary standards imposed by developed countries, which has an impact on agricultural trade in developing countries (major producers ofem do cumprimento de rígidos padrões fitossanitários impostos pelos países desenvolvidos, o que impacta no comércio agrícola dos países em desenvolvimento (grandes produtores de frutas tropica
l fruits). Anthis). A antracnose
is a disease capable of causing economic impacts; therefore, technologicalé uma doença capaz de causar impactos econômicos; portanto, invest
ments areimentos tecnológicos são important
toes para preven
t the damage caused by this diseaseir os danos causados por essa doença.
2.2. ThO proce Infectious Process of Tsso infeccioso de frutas tropical Fruits byis por Colletotrichum
Th
O processo de contamina
tição
n process of healthy fruits is de frutas sadias é favore
d by the environmental factors ofcido pelos fatores ambientais das regiões tropica
l regions. The causes areis. As causas são divers
e and vary according to the region and the type of production. Generally, highas e variam de acordo com a região e o tipo de produção. Geralmente, altas temperatur
es (aroundas (cerca de 27 °C)
and moisture (arounde umidade (cerca de 80%)
highly affect anthafetam fortemente o desenvolvimento da antracnose
development in em frutas tropica
l fruits. Prolonged periods of rain inis. Períodos prolongados de chuva em regiões tropica
l regions together with high is juntamente com altas temperatur
eas favor
theecem a progress
ion of the disease. Cão da doença. A umidade constant
moisture on the leaf surface e na superfície da folha estimula
tes the infectious process and fungal growth. In the case of fruits, most are lost due to o processo infeccioso e o crescimento de fungos. No caso das frutas, a maioria se perde devido à contamina
tion during thção durante o processo de produ
ction and ripening processção e amadurecimento [
17].
TheO control
of environmental factors is ane dos fatores ambientais é um ponto important
point to bee a ser consider
ed in the post-harvest and storage process. Post-harvest diseases are a major cause of fruit and vegetable losses in the world. In this sense, anthado no processo de pós-colheita e armazenamento. As doenças pós-colheita são uma das principais causas de perdas de frutas e hortaliças no mundo. Nesse sentido, a antracnose
becomes a major concern fortorna-se uma grande preocupação para os produ
cers because the fungustores, pois o fungo associa
ted with this disease has caused losses in many species of mango, papaya, avocadodo a essa doença tem causado perdas em muitas espécies de manga, mamão, abacate, banana, ca
shewju, carambola, g
uava, passion fruit, and other fruitoiaba, maracujá e outras frutas [
17 ,
20 ]
.
A
ant
hracnose
is a disease ché uma doença caracteriz
ed by the appearance of symptoms mainly during fruit ripening, i.e., during the post-harvest period, inada pelo aparecimento de sintomas principalmente durante o amadurecimento dos frutos, ou seja, no período pós-colheita, em espécies clima
cteric species. Dead leaves and infected branches or fruits can be a source oftéricas. Folhas mortas e galhos ou frutos infectados podem ser uma fonte de contamina
tion, andção, e a infec
tion can occur at any stage between fruiting and harvesting. Conidiospores, fungal germ structures, can beção pode ocorrer em qualquer estágio entre a frutificação e a colheita. Os conidiósporos, estruturas germinativas de fungos, podem ser dispers
ed by wind or water. Whenos pelo vento ou pela água. Quando dispers
ed, they can adhere to the surface of the fruits andos, podem aderir à superfície dos frutos e germina
te in a short time. Soon after, theyr em pouco tempo. Logo depois, produ
ce thezem o tubo germina
l tube, which tivo, que penetra
tes the cuticle of the fruit. After na cutícula do fruto. Após a penetra
tion, the hyphae can cção, as hifas podem coloniz
e the fruit wall. The initial epidermal lesions are small andar a parede do fruto. As lesões epidérmicas iniciais são pequenas e circular
, with a dark brown or, in some cases, black color. Smalles, de coloração marrom-escura ou, em alguns casos, negras. Pequenas lesões circular
lesions become soaked with water, looking deeper than the surface of the fruit. They may increase in size with age, and the center of an older spot becomes blackened and developes ficam encharcadas de água, parecendo mais profundas do que a superfície do fruto. Podem aumentar de tamanho com a idade, e o centro de uma mancha mais velha torna-se enegrecido e desenvolve massas gelatino
us masses of pink or orange spores. In a few days, with the increase in size during ripening, the lesions sas de esporos rosa ou laranja. Em poucos dias, com o aumento de tamanho durante o amadurecimento, as lesões apresent
initial points ofam pontos iniciais de necros
is, leading to fruit loss (e, levando à perda dos frutos.Figurea 1 ) [
19 ,
21 ].
Figurea 1. SchEsqueme ofa da visão microscopicópica ( A ) ande macroscopicópica ( B ) view of anthdo desenvolvimento da doença antracnose disease development.
2.3. O The estilo de vida do Colletotrichum Lifestyle and Its Relationship with the Symptoms of Anthe sua relação com os sintomas da antracnose
The
A rela
tição
nship between fungi and entre fungos e plant
s is highlyas é altamente complex
, as ita, pois depend
s on changee de mudanças rela
ted to difcionadas às diferent
stages ofes fases da vida da plant
life, as well as on the physiological developmenta, bem como do desenvolvimento fisiológico, resist
ance to the host, the environment, andência do hospedeiro, do ambiente e dos genes associa
ted with the diseasedos à doença [
22 ].
The O gênero Colletotrichum genus isé form
ed by a group ofado por um grupo de important
phytopathogens that cause large losses of fruits, vegetablees fitopatógenos que causam grandes perdas de frutas, hortaliças, cerea
lis, gra
sses, and ornamentalmíneas e plant
s in tropical regions [19]. Thas orname
re is n
o established standard for the lifestyle of the different species and groups that make up the Colletotrichum genus, hampertais em regiões tropi
ng the c
ontrol of the diseases causedais [ by19 them [23].
Th Não e
lxi
festyle of this genus can be broadly categorized by some characteristics that arise throughout the life cycle of the fungus. The Colletotrichum genus can be classifste um padrão estabeleci
ed
as follows: (i) necrophytes, almost all of which use lytic enzymes or toxins to cause cell death at some stage of the infectious process; (ii) endophytes, which inhabit plant cells in the process of symbiosis without causing apparent disease; (iii) quiescent species, whose fungus remains in latency or a dormant stage with no activity and generally becomes active in the post-harvest moment; (iv) biotrophic species, a characteristic common in the early lifestyle ofo para o estilo de vida das diferentes espécies e grupos que compõem o gênero the genus Colletotrichum ,
when the fungus remains alive inside the cells, actively absorbing the plant’s metabolites for its development without killing the cells [24,25].
The complex lifestyle of the Colletotrichum genus associatedificultando o controle d
with its a
bility to change style and the potential to infect different host species are factors that hinder the management of contaminated fruits and vegetables. Thes doenças por eles causadas [ lifestyle23 of].
O this ge
nus is highly regulated by specific genes and by specific biochemical interactions, in which enzyme activity and the production of secondary metabolites specific to the pathogen–host interaction occur [25]. In this stilo de vida desse gênero p
ro
cess, it is necessary to consider not only symptomatic fruits but also asymptomatic ones, as both can disperse the infectious agent to other plants. Knowledge of the lifestyle, the different stages of development, and the mechanisms that species of Colletotrichum use for de ser amplamente categorizado por algumas caract
he disease
progression is essential to avoid commercial losses and allow for the exportation of fruits and vegetables.
Therísticas que s
tru
cture of the host plant is an important point in the pre-infection moment, since the presence of cuticles, stomata, and trichomes and the thickness of the epidermis can be initial barriers to the infection process [26,27].rgem ao longo do ciclo de vida do fungo. O Gegêner
ally,o Colletotrichum infpode
ctions start with the germination of conidia and the formation of specialized infectious structures (appressoria) that facilitate the entry through the cuticle and cell wall [28]. However, the ser classificado da s
pe
cies C. gloeosporioides, when iguin
fect
ing blackberry leaves, for example, formed specialized vesicles on or inside stomata, allowing the hyphae to enter the leaves [29]. In another e forma: (i) nec
ase, C. orbiculare pr
oduced an appressorófi
um to disrupt the plant’s surface and cause lytic enzymes to digest the cuticle and cell wall, allowing the conidia of this species to adhere [30].
After penetrattas, quase todas utilizando enzimas líti
on, different spec
ies can start an intracellular or subcuticular hemibiotrophic process, generating an asymptomatic biotrophic phase without cell death. Subsequently, fungi can enter the necrotic phase, where secondary hyphae grow in the intracellular and intercellular space, which secrete degrading enzymes from the wall, leading to cell death [23]. In as ou toxinas para causar a morte celular em alguma fa
ddition to this
mechanism, some species may initiate the pe do process
of subcutaneous intramural necrotrophic infection, where fungi grow under the cuticle between the periclinal and anticline walls without the penetration of protoplasts [28o infeccioso; (ii) endófitos,
31]. Infections caqu
sed by C. gloeosporioides e ha
ve already b
een reported as intracellular hemibiotrophic in guava fruits, where vesicles and hyphae of infection were formed in the initially infected epidermal cell [32].
The interactiitam células vegetais em processo
n between the host and the microbiological agent during the development of anthracnose is complex and dynamic. The different lifestyles that this genus can adopt make the effective and economical treatment of this disease in tropical and subtropical fruits even more difficult [25]. Lossde simbiose sem causar doença aparente; (iii) es
from contamination can imp
act the entire production process, leading to economic damage [33]. The coécies quiescent
rol and manageme
nt risks associated with the infection by Colletotrichum are s, cujo fun
damental pgo
ints to avoid the dispersion of the fungus and contamination of other fruits.
3. Conventional Treatments for Anthracnose Prevention
Tropi permanec
al and subtropical fruits have
been produced for subsistence and local distribution for many years. Investments in technology and improvements in transport and storage conditions have made the global commercialization of these fruits possible. The Southern Hemisphere has undergone significant changes in its production processes to reach the ideal standard for fruit exports to the Northern Hemisphere [34]. However, some chem estado de latência ou dormência sem atividade e geral
lmen
ges such as the lack of technology and infrastructure, high insect infestations, undesirable microbial growth, the appearance of lesions and stains due to improper handling or transport, and the prevalence of high temperatures and humidity still make the commercialization process difficult. In this context, the prevention of post-harvest diseases is essential to maintain the fruit trade and to reduce losses.
3.1. Physical Treatments
Durte se torna ativo no momento pós-colheita; (i
ng the post-harv
est stage, some traditional physical and chemical treatments can be applied to control the symptoms of anthracnose. Alvindia and Acda [35] evalua) espécies biotróficas, caracte
d the effectrís
of hot water application on anthracnose-causing mango crops. In this study, treatment at 53 °C for 20 min had a significant effect on reducing the germinationtica comum no estilo de vida inicial do gênero of Colletotrichum gloeosporioides spores after 48 h,
preserving the fruit qua
lity. However, the high amount of water used is a disadvantage of this type of treatment.
Othndo o fungo permane
r physic
al treatments have been evaluated in recent studies. Fischer et al. [36] used UV-C radiatioe vivo den
t
o control anthracnose symptoms of and stem rot in avocado fruits inoculated with C. gloeosporioides.ro das células, The a
pplied doses of UV-C radiation (0.34–0.72 kJ·m−2) werbsorve
n
ot effective in reducing the occurrence of the disease. Contrarily, by applying a higher dose of radiation (3.0 and 4.0 kJ·m−2), Wanasinghe and Damunudo ativamente os metabólitos da p
ol
a [37] successfully suppressed ant
hra
cnose symptoms on tomatoes. Nonetheless, these results should be evaluated with caution, because the authors observed the presence of antifungal compounds in tomato skins. Furthermore, radiation is still seen as a problem for consumers. Although it has minimal ambient impact, the lack of information about possible changes in food and, consequently, the possible impacts of this type of treatment on human health remain the main barriers to para seu desenvolvimento sem matar as células [ this24 method’s, acceptance25 [38].
3.2. Chemical Treatments
Some
O che
mical treatments are applied to reduce the symptoms of anthracnose in fruits, but most are toxic or less efficient over time as the pathogen’s resistance increases. Vieira et al. [39] stilo de vida comple
valuated the efficacy xo
f thiophanate-methyl, a fungicide frequently used to control Black Sigatoka, on the growth do gênero of Colletotrichum musae, which ca
uses anthracnose in bananas. Their results suggested a potential resistance of Colletotrichum musae to thssociado à sua capaci
ophda
nate-methyl, leading to treatment inefficacy. Thiabendazole showed poor growth control ofde de mudar de estilo Colletotrichum gloeosporioides in papaya, where
as the fungicides imazalil, prochloraz, propiconazole, and tebuconazole showed a positive effect by interrupting the germination of Colletotrichum gloeosporioides spoao potencial de infectar
es when applied at 50 ppm [40]. Even wdi
th satisf
actory results, the repeated and continued use of these pesticides can change the balance of ecosystems, increase the incidence and severity of diseases, and still select isolates resistant to these chemical compounds [41].
A successfuerentes espécies hospedeiras são fatores que dificul treatment for anthracnose control must consider environmental health impacts. Resources must be selected to maintain their balance in the environment, avoiding waste, without causing pollution or future damage. The treatments available to control anthracnose symptoms still face barriers, which can make them unfeasible or ineffective. The use of chemical or physical agents to reduce the growth of the Colletotrichum am o manejo de frutas e hortaliças contaminadas. O estilo de vida desse gênero é altamente regenus must meet safety criteria and environmental preservation. Therefore, an increasing number of studies have investigated potential natural pesticides capable of assuring fruit integrity, as well as safety and a reduction in losses.
4. Essential Oils
4.1. General Characteristics and Potential Applications
Several chelado por genes específicos e por interações bioquímicals substances have been applied to reduce the effects caused by fruit contamination after harvesting. Lately, most food producers have been forced to change this approach to meet the growing demand for chemical-free products, as the use of sustainable and safe natural products is progressively being demanded. Therefore, to meet consumer criteria, industries have had to look for new sources of compounds with effective action in the preservation process.
EOs are secondary plant específicas, nas quais ocorre a atividade enzimática e a produção de metab
oólit
es that consist of a complex mixture of compounds extracted from various parts of plants, such as leaves, flowers, buds, seeds, branches, bark, herbs, wood, fruits, and roots, and they have been increasingly explored due to their insecticide, antioxidant, anti-inflammatory, antiallergic, and anticancer potential [42,43]. The bios secundários específicos para a interação patógeno
activity of t-h
e molecules present in EOs makes them very attractive to theospedeiro [ food25 industry,]. both for direct application, as a potential natural preservative in food formulation, and for indirect application, in the production of active packaging, e.g., to improve food preservation by preventing pathogenic and/or spoilage microorganisms [44,45].
CaNesse processo, é necessário considerar não apenas os fr
out
enoids, alkaloids, phenolic compounds, flavonoids, isoflavonoids, and aldehydes are the groups commonly found in the composition of EOs [43]. Moreoveros sintomáticos, mas também os assintomáticos,
EOs are rich in substances classified as terp
enes, terpenoids, and phenylpropanoid homologs [46], which contain several comois ambos po
und
s associated with different bioactivities. Some studies have suggested that the antimicrobial activity of essential oils may be directly related to major components, but there is also a possibility of synergy or antagonism among the different components [47]. Fem dispersar o agente infeccioso para outras plantas. O conhecimento
r example, Hyldgaard, Mygind, and Meyer [48] dedo es
crti
bed the low efficiency of isolated terpenes against the growth of Escherichia colilo de vida,
Staphylococcus aureus, Bacillus cereus, da
nd the fungus
Saccharomyces cerevisiae, and
specif
ic terpenoids such as carvacrol and thymol have been reported as potent antimicrobial agents when isolated. Chavan and Tupe [49] erentes fases de de
mons
trated the synergism between carvacrol and thymol in vitro and in vivo, which promoted membrane damage and cytoplasmic leakage of wine spoilage yeasts.
The envolvimento e dos mecharacteristics of different essential oils can be exploited to prevent or reducnismos que as espécies de the damage caColletotrichumusedo by anthracnose in fruits. However, for the treatment to be effective, it is necessary to elucidate the mechanisms of action of the different components of EOs against fungal growth.
4.2. Mechanism of Action against Fungi
Thpara a progressão da doença é e
mechanis
m of action of essential oils against fungal development is not yet fully understood. Nevertheless, some studies have suggested potential antimicrobial activity based on the functional group structures of compounds present in EOs [50]. The strsencial para evitar perdas comerciais e permitir a exportação de fru
ct
ure of compounds in EOs determines their hydrophobicity, allowing pasas e hortaliças.
A es
age t
hrough the cell wall and membrane, leading to increased permeability and, consequently, to cell death or inhibition of sporulation and germination of fungi [51]. The literature rerutura da planta hospedeira é um po
rnt
s that phenolic compound structures are associated with the high antimicrobial potential of clove, thyme, oregano, cinnamon, rosemary, sage, and vanilla EOs [47].
Hydo importante no momento da pr
ophobé-i
c components can interfere with synthesis reactions in wall structures, affecting morphogenesis and hyphal growth [52]. Somnfecção, pois a pre
s
tudies have suggested that hydrophobic compounds interact with ergosterol, the essential molecule that maintains the cellular integrity, viability, function, and normal growth of the fungus. Clove and thyme essential oils are effective in inhibiting ergosterol synthesis [53,54]. Chença de cutículas, estômatos e tricomas e a espessura
nging the fluidity and permeability of the membrane leads to loss of ions, collapse of the proton pump, and reduction in membrane potential; moreover, in some cases, interactions between phenolic compounds and membrane proteins can occur, precipitating them and resulting in leakage of intracellular components [55,56].
The antda epiderme podem ser barreiras inici
funga
l activity of essential oils may also be related to the disruption of fungal mitochondria. Some EOs can inhibit specific enzymes, such as mitochondrial ATPase, malate dehydrogenase, and succinate dehydrogenase, decreasing energy metabolismis ao processo de infecção [
57]. In26 addition,
essential27 oils]. can alter the mitochondrial membrane of fungi, changing electron fluxes through the electron transportGeralmente, as infecções por chainColletotrichum and, thus, produc
ing altered levels of reactive oxygen species (ROS), which can oxidize and damage important molecules such as DNA, proteins, and lipids [58]. Thomeçam com a germinação de
inc
rease in ROS is closely related to the biochemical process of cell death. Terpenes, for example, are structures capable of causing an increase in ROS species [54].
Sonídios e a formação de estruturas infeccio
me s
tudies have shown promising results using essential oils to inhibit fungal growth. Essential oils of oregano, onion, mint, basil, and rosemary were tested against Fusarium sas especializadas (ap
., Aspergillus ochraceus, Aspergillus flavus, and Aspergillus niger. Ore
gano ess
ential oil showed a fungicidal and fungistatic effect on all samples of fungi, while the other oils had a less pronounced effect, which could be improved by adjusting the dosage [59]. Colletotrichum musae and Colletotrichum gloeosporioides isoórios) que facilitam a entrada pela cutícula e parede cel
ated from mango and banana fru
its were treated with eugenol and rosemary (Rosmarinus officinalis),lar [ eucalyptus28 (Eucalyptus citriodora),]. aEn
d copaiba (Copaifera langsdorffii) essent
ial oils. Rosemar
y and eucalyptus essential oils inhibited the growth of C. musaeetanto,
copa
iba oil was efficient espécie against C. gloeosporioides, a
nd eugeno
l showed antifungal activity against both species [60]. Some stu infectar folhas d
ie
s related the antifungal activity of secondary plant metabolites to their penetration into the hyphal wall, damaging the lipoproteins of the cytoplasmic membrane and leading to cytoplasmic extravasation, as well as emptying, dehydration of hyphae, and the presence of filaments [60,61].
The info amora-preta, por exemplo, forma vesículas especializadas sobre ou dentr
matio
n presented in this section demonstrates the possible application of essential oils as biofungicides. The complex chemical profile and specific characteristics of the molecules dos estômatos, permitindo que as hifas entrem nas folhas [ present29 in]. E
Os enable their antimicrobial effect. Although further elucidation regarding the mechanism ofm outro caso, action against the C. olletotrichum genus shrbicularepro
du
ld be established, there is a robust body of data indicating the fungicidal properties of EOs. The versatility of essential oils, as well as the chemical variety present in these oils, can be an alternative to reduce the barriers imposed by the complex lifestyle of the genus Colletotrichum.
5. Active Films and Coatings
Fziram um apressório para romper a superfície da planta e fazer com que enzi
lm
s and coatings are thin layers, usually up to 0.3 mm thick, that have been used for centuries to protect foods from structural damage and nutritional losses [62]. Films anas líticas digerissem a cutícula e a parede celular, permitindo a adesão d
co
atings can improve the physical strength ofs conídios dessa espécie [ foods30 and can act a].
Após a
barripe
r against gases and water vapor, decrease moisture migration, control microbial growth, reduce changes caused by light and oxygen, and improve visual and tactile characteristics. Thus, they are usually applied to increase the quality and shelf life of food products, protecting them from physical, chemical, and biological deterioration [63,64].
Binetração, diferentes espécies podem iniciar um processo hemibiotrófico intracelular o
basedu polymers commonly used in film and coating formulations are extracted from plants, animals, or microorganisms. Hydrocolloids are easily applied as biopolymers, with proteins and polysaccharides being the most used [65,66]. Somsubcuticular, gerando uma fase biotrófica assintomática sem morte ce
formlula
tions can be added with oils or fats, such as triglycerides, waxes, free fatty acids, and vegetable oils, to improve the water vapor barrier properties, due to the hydrophobic nature of these materials. Biopolymer-based coatings have been applied to fruits such as mango, apricot, and papaya, promoting an increase in their shelf life by preserving texture and reducing weight loss and respiration rate [67,68,69].
The r. Posteriormente, os fungos podem entrar na fase necrótica, onde hifas secundárias crescem no espaço in
corpotra
tion of substances with antimicrobial potential in the production of coatings and films has been suggested as a strategy to maximize their benefits to the quality and safety of fresh products and further increase their shelf life [70celular e intercelular, que secretam enzimas degradantes da parede,
71]. These are the so-calle
d “active films and coatings”, which can promote the controlled release ofvando à morte celular [ active23 compounds].
Depending on the application, migration rates can be reduced, immediate, extended, and specific or absent. Chemical bonds between the materials and the active substance must be considered, as well as the environmental factors that may regulate the migrationAlém desse mecanismo, algumas espécies podem iniciar o process
of the active compound. Many active compounds of different natures can be applied to form the active packaging, the most common being fertilizers, repellents, pesticides, antimicrobials, antioxidants, bioactive nutraceuticals, paints, and flavors [53,71].
As previoo de infecção necrotrófica intramural subcutânea, onde os fu
sly men
tioned, EOs are substances with a broad spectrum of activity against fungi and bacteria, which can be added to films and coatings to increase the shelf life of foods [72]. EOs agos crescem sob a cutícula entre as paredes per
e hi
ghly volatile, unstable, and hydrophobic; therefore, they are usually added in the form of emulsions, ensuring uniform dispersion [73].
The use of coclinal e anticlinal sem a
tings and active films containing essential oil emulsions to control phytopathogens haspenetração de protoplastos [ been28 explored, by31 several]. researchers [74,75]. CInfecções ca
susa
va starch films incorporateddas por with clove essential oil were applied to bananas and showed efficient antifungal activity against Colletotrichum. gloeosporioidesjá and Colletotrichum musae [76]. Mfo
st studies showed pr
omising results, encouraging different research groups to continue improving the methods and techniques related to the formulation of these packages. An analysis of these studies will make it possible to understand the current results while presenting new alternatives for even more auspicious results. Although the future seems promising for this technology, the lack of machinery to produce films and coatings with high productivity and low energy consumption is a major challenge for scaling up this technology. Additionally, the mechanical strength and barrier properties of active packings need improvementsam relatados como hemibiotróficos intracelulares em goiabeiras, onde vesículas e hifas de infecção foram formadas na célula epidérmica inicialmente infectada [ to32 compete].
A wi
th the long-established petroleum-derived plastics; furthermore, as a new technology, films and coatings should prove their safety to conquer consumer acceptance [62].
6. Emulsions
Despinteração entre o hospedeiro e o agente
all themi
r benefits, the use of EOs is a challenge, due to their lipophilic, volatile, and highly oxidizable nature [77]. These chcrobiológico dura
racnte
ristics hamper the direct application of essential oils in foods, reducing their biological activity and promoting undesirable organoleptic alterations. A delivery system compatible with food applications can minimize these impacts and retain the biological activity of EOs [78]. I o desenvolvimento da antracnose é complexa e dinâmica. Os diferen
t
his sense, emulsions are easy-to-formulate delivery systems that can be applied to protect EOs against environmental factors and to ensure the effectiveness of their application.
6.1. Conventional Emulsions
Anes estilos de vida que esse gênero pode adotar tornam ainda mais difícil o tratamento e
mulsfi
on consists of two immiscible liquids, with one of them dispersed as small spherical droplets in the other. Emulsions formed by water and oil and can mainly be classified as water-in-oil (w/o)caz e econômico dessa doença em frutas tropicais e subtropicais [ emulsions25 (water]. droplets dispersed in an oil phase) or oil-in-water emulsions (oil droplets dispersed in a water phase). They have relevant use in several areas, including the food sector. In addition to being present in many natural or processed foods, they are also used in delivery systems for functional compounds such as vitamins, nutraceuticals, aroma, flavor, color, and preservatives [13]. EmulsioAs perdas por contaminação podem impactar todo o processo produtivo, levan
systems enable the ad
ministration of active compounds through encapsulation, which can preserve and control the release of functional ingredients, improving efficiency, handling, and/or stabilityo a prejuízos econômicos [
79 33 ].
Some Os
tudies have incorporated EO emulsions in active coatings and films, exploring their antimicrobial activity to prevent anthracnose symptoms in different fruits. Emulsified essential oils from riscos de controle e manejo associados à Allium sativum, Copaifera langsdorfii, Cinnamomum zeylanicum, ain
d Eugenia caryophyllata wfe
re inc
orporated into polymericção por coatings to control the symptoms caused by Colletotrichum musae in bananas
. All treatments reduced the incidence, lesions, and disease severity [80]. The progression of ão pontos fundamentais para evita
nthr
acnose in papayas caused by Colletotrichum gloeosporioides and Colletotrichum brevisporum wa a dis
p
revented by applying chitosan coatings added with essential oil of Mentha piperita L. or Mentha × villosa Hersão do fu
ds emulsingo
ns. The formulations e a conta
ining 5 mg/mL of chitosan and 0.6 μL/mL ofminação Mentha piperitade o
il outr
1.6 μL/mL of Mentha × villosa Has fru
dtas
oil .
3. Tratamentos Convencionais para Prevenção da Antracnose
Fr
edu
ced the development of lesions similarly or superiorly to commercial fungicides [81].tas tropicais The
in vitro and in vivo potential of cassava starch films incorporated with lemongrass, thyme, and oregano essential oils was evaluated against Colletotrichum musae fsubtropicais são produzidas para subsistência e distr
om ib
ananas. Oregano oil inhibited mycelial growth and the complete in vitro germination ofuição local há muitos anos. C. musae coIn
idia. Lve
mongrass and thyme essential oils and two percent and three percent cassava starch films, as well as their combination, were effective in reducing and preventing anthracnose lesions in banana fruits [82]. All thstimentos em tecnologia e melhorias nas condições de transporte
se studies suggest that the use of emulsified essential oils incorporated into coatings or films can inhibit the growth of anthracnose-causing fungus in tropical fruits.
Le armazenamento possibilitaram a comercializa
teção gl
y, several studies have shown that the droplet size strongly affects the bioactivity of essential oil emulsions. A nanoemulsion is a scarcely explored strategy in combating the Colletotrichum genuobal dessas frutas. O Hemisfério Sul passou por mudanças
, but recent studies have indicated that its benefits can surpass those of macroemulsions, depending on the materials used and the application. On a nanometric scale, emulsions may have higher bioactivity and greater stability, and they may cause little change in the physicochemical characteristics of fruits [78,83].
6.2. Nanoemulsions
Csignificativas em seus processos produtivos para atingir o padrão ideal de exportação de frutas para o
nventional emulsions are characterized byHemisfério Norte [ an34]. averageNo droplet radius ranging between 100 nm and 100 µm, and nanoemulsions have an average droplet radius ranging between 10 and 100 nm [84]. Reduentanto, alguns desafios como a falta de tec
in
g droplets to a nanometric scale decreases the attractive forces acting on the droplets, consequently avoiding aggregation and coalescence. Furthermore, the conditions of physical stability are governed by Brownian motion, which ends up dominating the gravitational forces. As a result of the different forces acting on the droplets, nanoemulsions are more stable than emulsions [10,13,78].
Nanoologia e infraestrutura, alta infestação de insetos, crescimento microbiano indesejado, aparecimento de lesões e manchas de
mulsvi
ons are dispersions created with the aid of an energy source, which come from methods classified as high- or low-energy [85]. Low-energy medo ao manuseio ou transport
hods are
characterized by the spontaneous formation of small oil droplets, changing the solutions or the environmental conditions in which they are inserted. Phase inversioninadequado e prevalência de altas temperatur
e, phase inversion composition, membrane emulsion, spontaneous emulsification, and solvent displacement/evaporation are some of the methods for producing nanoemulsions under low-energy conditions. These methods have some disadvantages, such as the use of large amounts of solvent [86] or syntas e umidade ainda dificultam o processo de comercialização. Nesse contexto, a prevenção de doenças pós-colhe
ti
c surfactants [87]ta é and dif
ficulties in operating with large volumes of nanoemulsion solution [88].
High-undamental para mante
ner
gy methods use mechanical devices to create intense disruptive forces to disrupt the oil and water phases, forming tiny droplet o comércio de frutas e reduzir perdas.
Methods s
3.1. Tratamentos Físicos
Du
ch ra
s rotor–stator, ultrasound, and microfluidic homogenization or high-pressure valves are the most frequently applied to form nanoemulsions in high-energy systems. The disadvantages of these methods may be associated with long processing times, especially in high-pressure systems in which many cycles should be employed to form a homogeneous nanoemulsion, promoting lipid droplet coalescence and temperature increase during production [83]. High temnte a fase de pós-colheita, alguns tratamentos físicos e químicos tradicionais podem ser aplicados p
era
tures are critical for EOs during nanoemulsion formation processes, because the compounds present in these oils are volatile and sensitive to temperature increases. In this context, it is worth mentioning that when high-energy methods are applied,ra controlar os sintomas da antracnose. Alvindia e Acda [ it35 is] necessary to evaluate the retention of essential oil at the end of the process and, thus, to quantify the possible losses during the formation of the nanoemulsion.
6.3. Advantages of Using Nanoemulsions over Conventional Methods
As the droavaliaram os efeitos da apl
et si
ze decreases, the biological activity of the compounds encapsulated in the nanoemulsion system increases. This is because the transport of active molecules across cell membranes is performed more easily, and there is a greater relationship between surface and volume, impacting reactivity [10]cação de água quente em mangueiras causadoras de antracnose.
According to Donsí and FNe
rrari [78], the fus
ion of t
he small droplets of the nanoemulsions with the phospholipid bilayer of the microorganisms facilitates their access through the membrane surface, allowing their rupture and leading to cell death. Anwer et al. [89] obsere estudo, o tratamento a 53 °C por 20 min teve
d that clove essential oil nanoemulsion showed greater antimicrobial activity against several microorganisms (Bacillus subtilis, Staphyloccocus aureus, Proteus vulgaris, Pseudomonas aeruginosa, and Klebsiella pneumoniae) whefeito significativo na re
n compared
to pure essential oil. Pongsumpun, Iwamoto, and Siripatrawan [90] rução da ge
por
ted that cinnamon essential oil nanoemulsions showed greaterminação de esporos de activity against several fungi (Aspergillus niger, Rhizopus arrhizus, Penicillium sp., and Colletotrichum gloeosporioides) than the conventional emulsion, with inhibition halos more than twofold larger.
Napós 48 h, preservan
do
emulsions can exhibit an apolar phase and droplet size-dependent optical transparency. Systems with a droplet size below 40 nm usually form a transparent solution, whereas droplets in the range from 40 to 100 nm can result in turbid nanoemulsions (depending on the content of the nonpolar compound); lastly, emulsions with droplets above 100 nm are usually white due to significant multiple scattering [78,91]. Determining this relationship between droplet si a qualidade dos frutos. No entanto, a grande quantidade de água utiliz
e a
nd nanoemulsion color is critical, as color is an important attribute when applying films and coatings on foods [92].
Nanoda é uma desvantagem de
muls
ions have been used as encapsulation and delivery methods for bioactive compose tipo de tratamento.
Ou
nds, as t
hey are kinetically more stable than macroemulsions and less susceptible to coalescence, cream formation, flocculation, and sedimentation [93]. They cros tratamentos físicos foram a
n be va
pplied to extend the shelf life of foods, improving the stability and solubility of the encapsulated active compound. Furthermore, in nanoemulsified systems,liados em estudos recentes. Fischer et ai. [ the36 active] compound does not interact with environmental factors, and its release is usaram radiação UV-C para contro
lled and prolonged [94,95].
Nanoemullar si
on
s can provide droplets in sizes up to 200 nm, facilitating the interaction between the active compound and the fungus membrane. In this process, the availability, retention, and preservation of essential oils are improved [73]. Furthtomas de antracnose e podridão do caule em frutos de
rmore, in nanoemulsions, EOs behave differently than in simple emulsions. Nanoemulsified EOs can have a sustained release, prolonging the time of action against microorganisms.abacate inoculados com The essential oil of GC. gloeosporammiosciadium pterocarpumides Bioss.
was incorporated in the free form and nanoemulsified in films formed with whey protein isolate. Antioxidant and antimicrobial activity tests showed that films formed with nanoemulsions had significantly higher results than those formedAs doses aplicadas de radiação UV-C (0,34–0,72 kJ·m with−2 free) essential oil, confirming the distinct retention and release pattern of nanoemulsified oils in films described previously. In this case, the film with the nanoemulsified EO continuously released its EO content for a longer period of time, and the film with free EO discharged its EO content acutely in the medium [96].
Annão foram efetivas em reduzir a ocorrência da doença. Ao contrário, aplicando
ther advantage of using nanoemulsions is that when applied to films, there is better maintenance of the original matrix arrangement of the films because of the droplets’ nanometricuma dose maior de radiação (3,0 e 4,0 kJ·m diameter−2 [97].), The nWan
oemulsified cinnamon essential oil was incorporated into pullulan-based films. The small diameter and uniform size distribution of the droplets formed in the nanoemulsion were associated withasinghe e Damunupola [ an37] increas
ed EO retention rate and improved microbial activity of the film [98]. Theuprimiu com s
uce
studies corroborated the potential to expand the shelf life and quality of tropical fruits through the application of embedded EO nanoemulsion films and coatings.
Recent sso os sintomas de antr
esea
rchers have developed active films and coatings incorporated with EO nanoemulsions to improve the shelf life of many foods [99,100]cnose em tomates.
A cNo
ating formed with sodium alginate and eugenol, carvacrol, and cinnamaldehyde nanoemulsion was applied to Nanfeng mandarins. The entanto, esses result
s of this study showed an inhibitory effect on Penicillium digitatum growth and bettados devem ser
sta
bility of the physical parameters in treated fruits compared to untreated ones [100]. A thymovaliados com cautel
na
noemulsion incorporated in films prepared with chitosan and quinoa protein showed inhibition of Botrytis cinerea g, pois os autor
owth in che
rry tomatoes [101].
7. Current Scenario: Essential Oils in Active Film and Coating Formulations
Currently, ss ociety ibs showing great concern for the loss/waste of fruits and vegetables, as these are essentialervaram a presença de components in daily human diets around the world. Tropical fruits are highly perishable and suffer from diseases that cause significant losses in both production and marketing. Anthracnose is a very common disease that can be found in a wide variety of tropical fruits. The wrong management of anthracnose in some countries could promote a deleterious economic impact. Treating anthracnose and controlling postharvest symptoms can bring great improvements to the production of various fruits.
Tstos antifúngicos na casca do tomate. Além disso, a radiação ainda é vista como um problema para os consumidores. Embora tenhe current scenario of studies using EOs for the treatment of anthracnose reveals the concern of scientists in seeking clean and sustainable methods for this problem. More efficient and less aggressive treatments are needed at this time. The articles cited in Table 1 indicated pr impacto ambiental mínimomising, results regarding in vitro and/or fruit application tests. Therefore, this review proposes a deeper investigation of the application of nanoemulsified EOs for the treatment of anthracnose. The perspectives for the future are encouraging, and the knowledge gaps described in this review should be elucidated in the near future by robust and well-structured research. In this section, a survey of the main gaps and methods applied so far for the treatment of anthracnose with EOs is carried out.
A coa falta de informações sobre possíveis alterações na alimentação e, consequentemente, os possíveis imp
ila
tion of the most relevant studies found since the early 2000s, focusing on the use of essential oils incorporated or not into films and coatings for the treatment of fruits with anthracnose, is presented in Table 1. From these dctos desse tipo de tratamento na sa
ta, it can be concluúde
d that essential oils have a high potential to combat anthracnose symptoms in tropical fruits. All studies had in vitro tests reporting the antifungal effect of the oils against the Colletotrichum species tested. Fu humana continuam sendo as principais bar
thermore
, most studies used essential oils with direct application on the surface of the fruit or in the form of emulsions (without using high- or low-energy methods toiras para a aceitação desse método [ produce38 them)].
The st
3.2. Tratamentos Químicos
Algu
dies shown
in Table 1 us
ed essential oils from different sources or major components of EOs, with fungicidal and/or fungistatic capacity. Studies using active films and coatings for the treatment of anthracnose still focused on direct applications, spraying, or simple emulsions of EOs. The application of nanotechnology was not considered in most (approximately 80%) of these articles. Among the articles that considered the use of nanotechnology for the treatment of anthracnose and that used nanoemulsified essential oils, only two applied a nanoemulsion in films or coatings. Neither of these two studies presented a sensory evaluation of the fruits. Data on the sensory analysis of tropical fruits that were subjected to post-harvest treatment with films and active coatings are still scarce, especially for the treatment of anthracnose. Although nanoemulsions require less usetratamentos químicos são aplicados para reduzir os sintomas da antracnose em frutas, mas a maioria é tóxica ou menos eficiente ao longo do tempo à medida que aumenta a resistência do patógeno. Vieira e cols. [ of39 EOs,] they are rich in aromatic compounds that can provide significant changes in the original characteristics of the fruit, which may or may not be acceptable to consumers. Sensory evaluation is an effective tool to evaluate the influence of active packings on the sensory characteristics of tropical fruits, such as alterations in the taste, odor, and general appearance of the fruits.
When evaavaliaram a eficácia do tiofanato-metílico, fungicida frequentemente util
uiza
ting the studies for the treatment of anthracnose using nanoemulsified EOs presented in this review, some gaps were noticed. Did the application of nanotechnology to form emulsions with even smaller droplets have a significant effect on reducing fungal growth? Did thdo no controle da Sigatoka-negra, sobre o crescimento de
dropletColletotrichum musae size, remain nanometric after the nanoemulsions were added to film and coating solutions? These questions are important to justify the use of nanotechnology as a viable alternative to the treatment of anthracnose. Of the eight articles (Table 1) causador da antracnose em bananas. Seus result
ha
t used nanoemulsified EOs, only one presented data on the antifungal effect of the nanoemulsion in relation to the crude emulsion [90]. Thidos sugeriram uma potencial resis
result
could elucidate thência de
cost–benefitColletotrichum musae a
ssessment o
f the process, as it justifies the use of energy-generating mechanisms, which require greater investment, for nanoemulsion production. In addition, the evaluation of droplet size after coating or film production would guarantee the presence of EO nanoemulsions in the final and most important stages of active packing development (application and storage). In the two studies [102,103] th tiofanato-metil, levando à ineficácia do tratamento. Tiabendazol a
t present
ed EO nanoemulsions embedded in film or coating, there was no evaluation of the droplet size after the production of film/coating-forming solutions.
Theou baixo controle do crescimento d
ata pre
sented inColletotrichum gloeosporioides Table 1 dem
onstrate studies that achieved highly promising results regarding the inhibition of fungal growth and a consequent reduction in anthracnose symptoms. Regarding the in vivo results, the authors reported the inhibition of mycelial growth, the inhibition of fungal growth, and a reduction in lesions. Generally, the main effect in vitro was fungicidal, while that in vivo was fungistatic. Results in vivo indicated the high power of infection of the fungus and its resistance to the treatments tested. Some studies showed promising results with the use of EOs incorporated into active coatings to minimize the symptoms of anthracnose [81,82,104,105]. Howevemamão, enquanto os fungicidas imazalil, procloraz, propiconazol e tebuconazol apresentaram efeito positivo ao interr
, these studies did no
t use nanoemulsified EOs. Most of the articles that produced nanoemulsions (reported in Table 1) with the objective of inhibiting the growth of mper a germinação d
iffe
rent species of the genus Esporos de Colletotrichum gloeosporioides presequan
ted only in vitro results. This demonstrates how much improvement isdo aplicado a 50 ppm [ needed40 for]. this technology to reach the consumer market.
From the data Mesmo com resu
mmlta
rized in Table 1, it can be do
bs
erved that the use of an active coating/film has not yet been exhaustively evaluated. Films and coatings are made of natural and biodegradable products that can provide greater stability to the fruit during storage. The respiratory process of fruits continues after harvest, and films and coatings act as a physical barrier against gas and water vapor exchange, delaying the ripening and deterioration processes [97,106]. These f satisfatórios, o uso repetido e continuado desses agrotóxicos pode alterar o equilíbrio dos ecossistemas, aumentar a incidência e severidade de doença
ctors
, associated with the antifungal effect of EOs against phytopathogens, can guarantee an increase in shelf life, minimizing the symptoms of fruits infected with the genus Colletotrichum.
The potential benefits of treating anthracnose with nanoemulsified EOs incorporated into films or coatings are numerous. However, there are major challenges to overcome in order for this treatment to become an alternative to conventional anthracnose treatments. The choice of EOs considering their properties, the definition of the production method of nanoemulsions, and the selection of the best polymer for film and coating formation are still the main research questions in this area. This reveals the absence of robust studies involving the application of nanoemulsified EOs in films and coatings for the control of anthracnose symptoms in tropical fruits.
D e ainda selecionar isolados resistentes a esses
pite the great potential of EOs and the noticeable improvement in their properties whencompostos químicos [ they41 are in the for].
Um
of nanoemulsions, furt
her data is needed to confirm nanoemulsion superiority compared to crude emulsion and pure oil. Studies with consistent results on the reduction in anthratamento bem-sucedido para o controle da antracnose
symptoms in tropical fruits, especially those that are superior to conventional treatments, will be important to justify investments in this area. The evaluation of the commercial viability of the treatment using films and coatings should be considered. Tropical fruits are generally produced on a large scale to meet local consumption and export demands. Therefore, it would be interesting that future studies replicate a pilot-scale film/coating production; this type of work using highly commercialized fruits should bring awareness regarding technology viability, reality of the productive market, and the consumption profile.
From this redeve considerar os impactos na saúde ambiental. Os recursos devem ser selecionados para manter seu equilíbrio no meio ambiente, eview, the importance of future studies focusing on improving the formulation of nanoemulsions, as well as their application in tropical fruits, is clear. Evaluations of fruit quality and sensory characteristics, as well as the reduction in anthracnose symptoms, are essential to explain the use of coating-forming solutions or films loaded with nanoemulsions. With the increase in consumption of essential oils around the world, the regulation of these oils has been carried out little by little in partnership between organizations and governments. This scenario favors the use of EOs for the treatment of anthando o desperdício, sem causar poluição ou danos futuros. Os tratamentos disponíveis para o controle dos sintomas da antracnose from a commercial and a food safety point of view. In this sense, future studies that focus on the development of EO nanoemulsions incorporated in films and coatings can be an attractive and innovative alternative for the tropical fruit market.
8. Conclusions
Thiainda enfrentam barreiras, que podem inviabilizá-los ou ineficaz. A utilização de agentes químicos ou fís review has demonstrated that essential oil-based active films or coatings have been successful in treating anthracnose in many tropical fruits. The inhibition of the growthcos para reduzir o crescimento do gênero of the Colletotrichum gdenus in vitro and in vivo was a noticeable reality in almost all studies that used the active film or coating as a treatment. Studies showed that the application of essential oils in the form of nanoemulsions improved their antifungal potential, increased their efficacy, and reduced the amount needed, which are advantageous attributes from the sensory and economic points of view. However, to date, only a few recent studies have applied nanoemulsions for the treatment of anthracnose. In this way, nanoemulsions represent a reality that can be further explored in the area of food preservation, especially for the treatment of anthracnose. The advantages presented in this review reinforce the potential of nanoemulsions to improve the results already obtained and generate unprecedented results in inhibiting fungal growth and disease development. However, further studies are still needed for a cost–benefit analysis of this technology and to confirm the superiority and viability of EOs nanoemulsions incorporated with films and coatings compared to conventional treatmentve atender a critérios de segurança e preservação ambiental. Portanto, um número crescente de estudos tem investigado potenciais pesticidas naturais capazes de garantir a integridade das frutas, bem como a segurança e a redução de perdas.