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Topic Review
Lipid Oxidation Mechanism in the Oil-Based Food Products
In bulk oils, modifying the polarity of antioxidants by chemical methods (e.g., esterifying antioxidants with fatty alcohol or fatty acids) and combining antioxidants with surfactants with low hydrophilic–lipophilic balance value (e.g., lecithin and polyglycerol polyricinoleate) can be effective strategies for inhibiting peroxidation. Lipid oxidation is an important economic concern in the food industry, primarily because it can influence the quality attributes and nutritional profile of oil-based products. Food manufacturers often have different options to use different methods and reduce the oxidation rate of oil-based food products.
  • 782
  • 21 Mar 2023
Topic Review
Activation of Biosynthetic Gene Clusters in Fungi
In the early 2000s, technological advances in genome sequencing and bioinformatics on filamentous fungi began to reveal a discrepancy between the number of biosynthetic gene clusters (BGCs) encoding the biosynthesis of fungal secondary metabolites and the actual number of identified fungal compounds from the target strain. The discovery of cryptic BGCs in microorganisms, including fungi, has spurred the development of new experimental methodologies for identifying the secondary metabolites of these clusters, which led to the realization that they have the potential to produce novel specialized metabolites, giving rise to a new field of research called genome-guided natural product discovery.
  • 773
  • 01 Jun 2023
Topic Review
Application of Graphene Oxide in Electrochemical Biomarker Detection
Graphene, a single layer (monolayer) of SP2 carbon atoms with a molecular bond length of 0.142 nm, is tightly bound in a hexagonal honeycomb lattice. It is basically extracted from graphite and is merely a sheet of graphite.
  • 770
  • 01 Feb 2023
Topic Review
Synthetic Bioactive Compounds and Chromatography
Natural and synthetic bioactive compounds occur in foods in small quantities and represent a wide group of chemical compounds. Because of the complexity of food matrices, the separation and next accurate determination of their bioactive constituents with different chemical structure requires an universal analytical methodology like liquid and gas chromatography or combination of both chromatographic techniques.
  • 766
  • 29 Oct 2021
Topic Review
Mechanisms of Gas-Phase Oxidative Dehydrogenation of n-Octane
The oxidative dehydrogenation (ODH) of alkanes, whereby hydrogen is removed to form unsaturated compounds, is an important process, particularly in the petrochemical industry. The ODH of lighter alkanes (C3–C6) is well-reported in the literature, and there are several reports on the ODH of n-octane (C8).
  • 764
  • 23 Feb 2024
Topic Review
SIMS Applications in Metals and Alloys
Secondary Ion Mass Spectrometry (SIMS) is a powerful mass spectral imaging (MSI) technique, and it has been extensively employed for comprehensive surface analysis and characterization of materials. Its root traces back to 1910, and its early applications are in inorganic materials and semiconductors. During SIMS analysis, a high-energy primary ion beam bombards the solid surface. This interaction with the surface induces the emission of secondary ions (SIs), different from the primary ions, as well as neutral particles. These emanations originate from the top few layers of atoms at the surface. Subsequently, a mass spectrometer analyzes the extracted secondary ions, providing valuable insights into the composition and structural characteristics of the material composition. In contemporary applications, SIMS has evolved into an indispensable tool across diverse fields, such as materials research, medical research, geology, cosmochemistry, and the life sciences.
  • 748
  • 19 Feb 2024
Topic Review
Sn-Beta Catalyzed Transformations of Sugars
Beta zeolite modified with Sn in the framework (Sn-Beta) was synthesized and introduced as a heterogeneous catalyst for Baeyer–Villiger oxidations about twenty years ago. Since then, both syntheses strategies, characterization and understanding as well as applications with the material have developed significantly. Remarkably, Sn-Beta zeolite has been discovered to exhibit unprecedented high catalytic efficiency for the transformation of glucose to fructose (i.e., aldoses to ketoses) and lactic acid derivatives in both aqueous and alcoholic media.
  • 731
  • 14 Apr 2022
Topic Review
Squaraine-Based Fluorescent Materials
Squaraine dyes (SQs) are a peculiar class of cyanine dyes. One of the biggest structure differences between SQs and other types of cyanine dyes is that SQs contain an electron-deficient square ring at the center of the polymethine chain, leading to a quadrupolar donor-acceptor-donor (D-A-D) structure with a unique resonance-stabilized zwitterionic feature, as shown ina. In addition, the central square ring can make the polymethine chain rigid and planar to resist the photoisomerization and oxidation, and thus SQs intrinsically exhibit a greater stability over other cyanines.
  • 725
  • 27 May 2022
Topic Review
Environmental Applications of Organoclays
Natural clay mineral and its modifier called modified clay have been used in many environmental applications for a number of years. Clay is the best candidate for green chemistry materials because it is a natural material that is readily available and offers an attractive and cost-effective pollutant treatment option.
  • 724
  • 23 Aug 2023
Topic Review
Chemical and Biological Properties of Xanthohumol
Xanthohumol (Xn), a prenylated chalcone found in Hop (Humulus lupulus L.), has been shown to have potent anti-aging, diabetes, inflammation, microbial infection, and cancer properties. 
  • 719
  • 22 Mar 2024
Topic Review
The Pathways to Create Containers for Bacteriophage Delivery
Antimicrobial resistance is a global public health threat. One of the possible ways to solve this problem is phage therapy, but the instability of bacteriophages hinders the development of this approach. A bacteriophage delivery system that stabilizes the phage is one of the possible solutions to this problem. 
  • 718
  • 23 Feb 2022
Topic Review
The Hydrodeoxygenation of Lignin-Derived Fractions
Lignocellulosic biomass is a raw material used for the production of bio-oils and black liquors. These biomass-derived fractions offer promising paths for the production of valuable chemical products. Various catalytic methods have been investigated for upgrading the biomass-derived fractions. Researchers are interested in the hydrodeoxygenation process (HDO); in this process, the oxygen groups are eliminated by breaking the C-O bonds and water as a product. Crucial factors influencing this optimization include temperature, hydrogen pressure, catalyst selection, and physicochemical attributes of the catalyst itself, such as the surface area, porosity, and acid–base properties. However, the intrinsic nature of lignin requires careful investigation. The chemical structural network of this biopolymer is significantly influenced by factors such as plant species and extraction process. Understanding and accounting for these variables are imperative for tailoring processes that efficiently harness the potential of lignin and its derivatives.
  • 710
  • 29 Feb 2024
Topic Review Peer Reviewed
Formulation in Surfactant Systems: From-Winsor-to-HLDN
Formulation is an ancient concept, although the word has been used only recently. The first formulations made our civilization advance by inventing bronze, steel, and gunpowder; then, it was used in medieval alchemy. When chemistry became a science and with the golden age of organic synthesis, the second formulation period began. This made it possible to create new chemical species and new combinations “à la carte.” However, the research and developments were still carried out by trial and error. Finally, the third period of formulation history began after World War II, when the properties of a system were associated with its ingredients and the way they were assembled or combined. Therefore, the formulation and the systems’ phenomenology were related to the generation of some synergy to obtain a commercial product. Winsor’s formulation studies in the 1950s were enlightening for academy and industries that were studying empirically surfactant-oil-water (SOW) systems. One of its key characteristics was how the interfacial interaction of the adsorbed surfactant with oil and water phases could be equal by varying the physicochemical formulation of the system. Then, Hansen’s solubility parameter in the 1960s helped to reach a further understanding of the affinity of some substances to make them suitable to oil and water phases. In the 1970s, researchers such as Shinoda and Kunieda, and different groups working in Enhanced Oil Recovery (EOR), among them Schechter and Wade’s group at the University of Texas, made formulation become a science by using semiempirical correlations to attain specific characteristics in a system (e.g., low oil-water interfacial tension, formulation of a stable O/W or W/O emulsion, or high-performance solubilization in a bicontinuous microemulsion system at the so-called optimum formulation). Nowadays, over 40 years of studies with the hydrophilic-lipophilic deviation equation (HLD) have made it feasible for formulators to improve products in many different applications using surfactants to attain a target system using HLD in its original or its normalized form, i.e., HLDN. Thus, it can be said that there is still current progress being made towards an interdisciplinary applied science with numerical guidelines. In the present work, the state-of-the-art of formulation in multiphase systems containing two immiscible phases like oil and water, and therefore systems with heterogeneous or micro-heterogeneous interfaces, is discussed. Surfactants, from simple to complex or polymeric, are generally present in such systems to solve a wide variety of problems in many areas. Some significant cases are presented here as examples dealing with petroleum, foods, pharmaceutics, cosmetics, detergency, and other products occurring as dispersions, emulsions, or foams that we find in our everyday lives.
  • 708
  • 23 Sep 2022
Topic Review
Building Supercapacitors with Electrolytes and Carbon Electrodes
Supercapacitors (SCs), also known as “ultracapacitors”, are used in applications requiring rapid energy storage or high-power delivery. Carbon-based materials for supercapacitors derived from affordable coal deposits or crop waste with appropriate characteristics in terms of specific surface area, electrical conductivity, and charge/discharge stability. In addition, the substitution of organic liquids electrolytes with less dangerous solutions, such as aqueous electrolytes containing high concentrations of salt, is a valuable strategy for the design of green devices.
  • 703
  • 21 Jul 2023
Topic Review
Semiconductor Heterogeneous Photocatalysts
Semiconductor-based photocatalytic reactions are a practical class of advanced oxidation processes (AOPs) to address energy scarcity and environmental pollution. By utilizing solar energy as a clean, abundant, and renewable source, this process offers numerous advantages, including high efficiency, eco-friendliness, and low cost.
  • 694
  • 26 Jul 2023
Topic Review
Types of Soil Contaminants and Their Harmful Effects
Soil can be understood as a 3D structure that is interconnected with components of the environment, such as air and water. Therefore, if the soil is contaminated, the contamination can easily spread, leading to great risks to human life, ecosystems, water sources, and other environmental receptors. Additionally, the pollutants can be transmitted to the bodies of people who eat crops produced from the soil. The constant contact between dirt that is polluted and the air and water can be hazardous to the environment and human health. Trace elements can lead to digestive problems such as intense pains, diarrhea, vomiting, ulcers, skin problems, lung cancer, changes in genetic material, and other human illnesses.
  • 692
  • 04 Sep 2023
Topic Review
Graphene-Based Nanomaterials in Pb(II) Ions Preconcentration and Removal
Graphene-based nanomaterials have attracted significant interest as potential adsorbents for Pb(II) preconcentration and removal due to their high specific surface area, exceptional porosities, numerous adsorption sites and functionalization ease. Particularly, incorporation of magnetic particles with graphene adsorbents offers an effective approach to overcome the separation problems after a lead enrichment step.
  • 686
  • 06 May 2023
Topic Review
Cyclodextrins Application
Cyclodextrins are a family of macrocyclic polysugars. Although a wide range of ring sizes have been synthesised, the most common variants of these moieties are α, β and χ-cyclodextrins, which contain 6, 7 and 8 α-1,4-d-glucopyranoside units, respectively, in the macrocyclic ring.
  • 678
  • 07 Nov 2023
Topic Review
Cu-Based Catalysts in Nitrogen Oxides by CO
Selective catalytic reduction of nitrogen oxides (NOx) by CO (CO-SCR) to both N2 and CO2 is a promising way to simultaneously remove two harmful gases, CO and NOx, in automobile and factory exhaust gases. The development of efficient catalysts is the key challenge for the technology to be commercialized. The low-cost Cu-based catalysts have shown promising performance in CO-SCR, but there are some technical problems that obstruct their practical implementation, such as high reduction temperature and low O2, H2O, and SO2 resistance. An overview CO-SCR under O2-containing conditions over the Cu-based catalysts is discussed.
  • 673
  • 12 Jan 2023
Topic Review
Current Methods of Melasma Treatment
Melasma is a fairly common condition that is the result of hyperpigmentation caused by increased melanin secretion. In the course of melasma, certain areas of the skin become darker than the rest of the epidermis. Although the pathogenesis remains incompletely clarified, several contributing factors have been identified, namely exposure to ultraviolet and visible light, family predisposition, pregnancy, and the use of exogenous hormones. Since current beauty standards associate healthy skin with its flawless and uniform color, people strive to eliminate any unaesthetic discoloration.
  • 666
  • 06 Jul 2023
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