Conjugation of Lysozyme and Epigallocatechin Gallate for Improving Antibacterial and Antioxidant Properties

One of the main interests in the food industry is the preservation of food from spoilage by microorganisms or lipid oxidation. A novel alternative is the development of additives of natural origin with dual activity. In the present study, a chemically modified lysozyme (Lys) with epigallocatechin gallate (EGCG) was developed to obtain a conjugate (Lys-EGCG) with antibacterial/antioxidant activity to improve its properties and increase its application potential. The modification reaction was carried out using a free radical grafting method for the Lys modification reaction, using ascorbic acid and hydrogen peroxide as radical initiators in an aqueous medium. The synthesis of Lys-EGCG conjugate was confirmed by spectroscopic (FT-IR, 1H-RMN, and XPS) and calorimetry differential scanning (DSC) analyses. The EGCG binding to the Lys biomolecule was quantified by the Folin-Ciocalteu method; the antibacterial activity was evaluated by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MCB) against Staphylococcus aureus and Pseudomonas fluorescens; the antioxidant activity was evaluated by ABTS, DPPH, and FRAP. The spectroscopic results showed that the Lys-EGCG conjugate was successfully obtained, and the DSC analysis revealed a 20 °C increase (P < 0.05) in the denaturation temperature of Lys due to EGCG modification. The EGCG concentration in Lys-EGCG was 97.97 ± 4.7 µmol of EGCG/g of sample. The antibacterial and antioxidant activity of the Lys-EGCG conjugate was higher (P < 0.05) than pure EGCG and Lys. The chemical modification of Lys with EGCG allows for the bioconjugate with a dual function (antibacterial/antioxidant), broadening the range of Lys and EGCG applications to different areas such as food, cosmetic, and pharmaceutical industries.

Improvement of the oxidative stability of instant fried noodles using free and microencapsulated borage (Echium amoenum) and black hollyhock (Altaea rosea var nigra) extracts

This study investigated the oxidative stability of instant fried noodles by applying free and microencapsulated black hollyhock extracts (BHE) and borage extracts (BE) (BE, BHE, ME-BE and ME-BHE). At first, the BE and BHE were encapsulated with whey protein and maltodextrin at a 90:10 ratio through a spray dryer. After evaluating particle characteristics (including anthocyanin content, zeta potential, polydispersity index (PDI), particle size, and morphology), they were added to the noodle formulation (wheat flour 78.5%, NaCl 0.78%, and water 21.21%) at 1% w/w level, and the physicochemical (proximate analysis, pH, color, cooking loss, and texture), sensory properties (taste, odor, color, texture, and overall acceptability), and oxidative stability (acid value, peroxide value, anisidine index, thiobarbituric acid index, conjugated dienes) of the fried noodles were studied. The results showed that the microcapsules had uneven shapes with angular surfaces. There was no significant difference between the zeta potential, particle size, PDI, and encapsulation efficiency of BE- and BHE-loaded microcapsules, and the values reported fell between -34.96 and -34.84 mV, 1.128 and 1.195 μm, 0.247 and 0.283, and 80.08% and 83.47%, respectively. Adding extracts to the functional noodles decreased cooking loss and pH compared to the control. The noodles exhibited a darker color. BE and BHE reduced the oxidation of fried noodle oil, with microencapsulated extracts showing stronger effects during storage (p < .05). Sensory evaluation indicated high acceptability for all samples. Encapsulation effectively preserves the natural antioxidant activities of BE and BHE, providing potential benefits for food processing and storage.

Increased radical scavenging activity of thymoquinone and l-ascorbic acid dual encapsulated in palmitoyl-chitosan nanoparticles in a human normal lung fibroblast, MRC-5 due to synergistic antioxidative effects

Less effective antioxidant supplementation in combating free radicals is often related to the lack of the formulation of carriers. The antioxidant may be one of the most powerful substances but is marred by poor uptake by cells when the carrier degraded and dissolved too rapidly. Nanoparticle (NP) systems are promising in overcoming the problem since they provide high surface area to enhance encapsulation and release efficiency. With the right selection of material, NP carriers could function as constructive antioxidant cargos. Generally, NPs carry only one active ingredient; this study, however, utilized chitosan nanoparticles (CNPs) and hydrophobically modified palmitoyl-chitosan nanoparticles (PCNPs) that were dual encapsulated with antioxidants of different polarities, namely, hydrophobic thymoquinone (TQ) and hydrophilic l-ascorbic acid (LAA) to evaluate their combination effects in scavenging free radicals. The antioxidants followed zero-order release kinetics with a controlled release manner for about 48 h. The interaction effects between TQ and LAA loaded in the NP systems were determined by classical isobologram (CI) values. The CI values were derived by a diphenyl picrylhydrazyl (DPPH) assay, a radical scavenging activity assay. Combined TQ and LAA had CI values of less than one, with a lower value in the PCNP system than in the CNP system. This indicates that the interaction between those antioxidants showed higher synergistic effects in PCNPs, which enhanced the DPPH radical scavenging activities. The antioxidative potential of compound(s) encapsulated in the PCNP carrier was further experimented by a reactive oxygen species (ROS) assay on a human normal lung fibroblast cell line (MRC-5) as lung is one of the organs with high accumulation of free radicals. About 48 h post treatment, the dual-loaded TQ and LAA in PCNPs showed the lowest ROS level in comparison to single-loaded antioxidants and bare antioxidant delivery. The hydrogen peroxide (H2O2) radical scavenging was influenced by both the controlled release property of the PCNP system and the synergy between TQ and LAA. In short, dual-loaded TQ and LAA in the hydrophobically modified PCNP had effectively depicted the capability of a single CS-based nanocarrier to hold more than one compound at a time to function as a potent radical scavenger.

Evaluation of the Anti-inflammatory, Antimicrobial, Antioxidant, and Cytotoxic Effects of Chitosan Thiocolchicoside-Lauric Acid Nanogel

AIM

The present study explored the anti-inflammatory, antimicrobial, antioxidant, and cytotoxic effects of a combination of chitosan thiocolchicoside and lauric acid (CTLA) nanogel.  Materials and methods: A nanogel formulation of thiocolchicoside and lauric acid was developed and tested for potential applications. The antimicrobial activity was assessed using the well diffusion method, while the antioxidant activity was evaluated using the 2,2-diphenyl-1-picryl hydrazyl (DPPH) free radical scavenging assay and hydrogen peroxide (H2O2) antioxidant assay methods. The anti-inflammatory activity was determined through the egg albumin denaturation method, the bovine serum albumin denaturation method, and the membrane stabilization assay. A brine shrimp lethality assay was used to study the cytotoxic effect of the nanogel.

RESULTS

We identified significant positive outcomes for the CTLA nanogel. The results showed a percentage of inhibition of 81% at 50μg/mL, which showed the nanogel's significant anti-inflammatory activity by inhibiting bovine serum albumin denaturation. The anti-inflammatory properties of the nanogel were comparable to the standard diclofenac sodium at all tested concentrations. The egg albumin denaturation assay results revealed a percentage inhibition of 76% at 50 μg/mL. In the membrane stabilization assay, a percentage inhibition of 86% was obtained at a concentration of 50 μg/mL against 89% for the standard drug. The nanogel exhibited a zone of inhibition of 20 mm against Streptococcus mutans and 22 mm with a dilution of 100 µg/mL of CTLA nanogel against Staphylococcus aureus. The antioxidant activity was studied by using the DPPH method, 50 μg/ml has an 89% inhibition, which was similar to the standard. The inhibitory activity of CTLA nanogel at 50 μg/ml was 81.6% in the hydroxyl free radical scavenging assay, which was comparable to the standard drug. At 5 μg/mL concentration of CTLA nanogel, approximately 90% of the nauplii remained alive after 48 hours.

CONCLUSION

The CTLA nanogel showed excellent anti-inflammatory and antioxidant properties suggesting its potential for managing inflammatory conditions and oxidative stress-related disorders.

Chitin and Chitosan as Polymers of the Future-Obtaining, Modification, Life Cycle Assessment and Main Directions of Application

Natural polymers are very widespread in the world, which is why it is so important to know about the possibilities of their use. Chitin is the second most abundant reproducible natural polymer in nature; however, it is insoluble in water and basic solvents. Chitin is an unused waste of the food industry, for which there are possibilities of secondary management. The research led to obtaining a soluble, environmentally friendly form of chitin, which has found potential applications in the many fields, e.g., medicine, cosmetics, food and textile industries, agriculture, etc. The deacetylated form of chitin, which is chitosan, has a number of beneficial properties and wide possibilities of modification. Modification possibilities mean that we can obtain chitosan with the desired functional properties, facilitating, for example, the processing of this polymer and expanding the possibilities of its application, also as biomimetic materials. The review contains a rich description of the possibilities of modifying chitin and chitosan and the main directions of their application, and life cycle assessment (LCA)-from the source of the polymer through production materials to various applications with the reduction of waste.

Efficient Utilization of Tea Resources through Encapsulation: Dual Perspectives from Core Material to Wall Material

With the high production and consumption of tea around the world, efficient utilization of tea byproducts (tea pruning, tea residues after production, and drinking) is the focus of improving the economy of the tea industry. This review comprehensively discusses the efficient utilization of tea resources by encapsulation from the dual perspectives of core material and wall material. The core material is mainly tea polyphenols, followed by tea oils. The encapsulation system for tea polyphenols includes microcapsules, nanoparticles, emulsions, gels, conjugates, metal-organic frameworks, liposomes, and nanofibers. In addition, it is also diversified for the encapsulation of tea oils. Tea resources as wall materials refer to tea saponins, tea polyphenols, tea proteins, and tea polysaccharides. The application of the tea-based delivery system widely involves functionally fortified food, meat preservation, film, medical treatment, wastewater treatment, and plant protection. In the future, the coencapsulation of tea resources as core materials and other functional ingredients, the precise targeting of these tea resources, and the wide application of tea resources in wall materials need to be focused on. In conclusion, the described technofunctional properties and future research challenges in this review should be followed.

An Ecological Approach to Control Pathogens of Lycopersicon esculentum L. by Slow Release of Mancozeb from Biopolymeric Conjugated Nanoparticles

To control insects, weeds, and infections in crops, old-fashioned pesticide formulations (with massive quantities of heavy metals and a variety of chemicals) are used. By biological amplification via the food chain, many of these established pesticide formulations have accumulated in living systems and caused environmental pollution. To form a nanoparticulate matrix with a diameter ranging from 322.2 ± 0.9 to 403.7 ± 0.7 nm, mancozeb was embedded in chitosan-gum acacia (CSGA) biopolymers and loadings were confirmed via TEM and FTIR. Differential scanning calorimetry analyses were carried out as part of the investigation. Inhibition of Alternaria alternata by nanoparticles (NPs) with 1.0 mg/mL mancozeb (CSGA-1.0) was 85.2 ± 0.7 % at 0.5 ppm, whereas for Stemphylium lycopersici it was 62.1 ± 0.7% in the mycelium inhibition method. NPs demonstrated antimicrobial action in pot house environments. After ten hours, the mancozeb was liberated from the nanoformulations due to polymer matrix diffusion and relaxation, compared to 2 h for commercial mancozeb. Even while drug-loaded conjugated nanoparticles have equivalent antifungal activities, they have a lower release rate and, hence, reduced toxicology compared to commercial mancozeb. Therefore, this method can be employed to implement sustainable farming techniques in the future.

Green Tea Extract in the Extender Improved the Post-Thawed Semen Quality and Decreased Amino Acid Mutation of Kacang Buck Sperm

This study was the first to combine the addition of antioxidants to a skim milk–egg yolk (SM–EY) extender and different equilibration periods to obtain higher quality post-thawed Kacang buck semen. This study aimed to determine the effects of green tea extract (GTE) on the quality of frozen Kacang goat sperm equilibrated for one and two hours. The pool of Kacang buck ejaculate was equally divided into four portions and was diluted in an SM–EY extender that contained four doses of 0, 0.05, 0.10, and 0.15 mg of GTE/100 mL for T0, T1, T2, and T3 groups, respectively. The aliquots were treated for an equilibration period of 1–2 h before further processing as frozen semen. Post-thawed semen quality was evaluated for sperm quality. The Sanger method was used for DNA sequencing, and the amino acid sequence was read using MEGA v.7.0. The post-thawed semen of the T2 group that was equilibrated for one hour had the highest semen quality. Pre-freezing motility had the highest determination coefficient compared to post-thawed sperm motility. This study is the first to report amino acid mutation due to freeze–thawing. The frequency of amino acid mutations revealed that T2 was the least mutated amino acid. Glycine, valine, leucine, serine, and asparagine strongly correlated to post-thawed sperm motility. It can be concluded that a combination of 0.1 mg GTE/100 mL extender as an antioxidant and one-hour equilibration period resulted in the best post-thawed Kacang buck semen quality.

Current Advances of Polysaccharide-Based Nanogels and Microgels in Food and Biomedical Sciences

Polysaccharides are natural polymers with hydrophilic, biocompatible and biodegradable characteristics and have many opportunities in the food and pharmaceutical sectors. This review focuses on the field of nano and microstructures whose internal structure is based on networked polysaccharide chains in 3D i.e., polysaccharide nanogels (NGs) and microgels (MGs). As it is observed the number of articles on NGs and MGs in peer reviewed scientific journals has been increasing over the last two decades. At the same time, the relative contribution of polysaccharides in this field is gaining place. This review focuses on the different applied methods for the fabrication of a variety of polysaccharide-based NGs and MGs and aims to highlight the recent advances on the subject and present their potentials and properties with regards to their integration in aspects of medicinal and food sciences. The presentation of the recent advances in the application of polysaccharide NGs and MGs is divided in materials with potential as emulsion stabilizers and materials with potential as carriers of bioactives. For applications in the medical sector the division is based on the fabrication processes and includes self-assembled, electrostatically complexed/ionically crosslinked and chemically crosslinked NGs and MGs. It is concluded that many advances are expected in the application of these polysaccharide-based materials and in particular as nutrient-loaded emulsion stabilizers, viscosity modifiers and co-assembled structures in combination with proteins.

Nano-Strategies for Enhancing the Bioavailability of Tea Polyphenols: Preparation, Applications, and Challenges

Tea polyphenols (TPs) are among the most abundant functional compounds in tea. They exhibit strong antioxidant, anti-inflammatory, and anti-cancer effects. However, their instability and low bioavailability limits their applications. Nanotechnology, which involves the use of nanoscale substances (sizes ranging from 1 to 100 nm) to improve the properties of substances, provides a solution for enhancing the stability and bioavailability of TPs. We reviewed the preparation, performance, effects, and applications of different types of TPs nanocarriers. First, we introduced the preparation of different nanocarriers, including nanoparticles, nanoemulsions, nanomicelles, and nanolipids. Then, we discussed various applications of tea polyphenol-loaded nanocarriers in functional ingredient delivery, food quality improvement, and active food packaging. Finally, the challenges and future development directions of TPs nanocarriers were elucidated. In conclusion, a nano-strategy may be the “key” to break the application barriers of TPs. Therefore, the use of nano-strategies for the safe, stable, and efficient release of TPs is the direction of future research.

Recent advancements in encapsulation of bioactive compounds as a promising technique for meat preservation

Encapsulation is currently considered as one the most valuable methods for preserving aromatic compounds or hiding odors, enhancing their thermal and oxidative stability, and expanding their food applications. Indeed, this current article was aimed to provide an overview regarding the encapsulation of plant bioactive compounds and the spray-drying and extrusion processes with a focused discussion regarding the encountered challenges for meat and meat product preservation. Furthermore, different ranges of carbohydrates as wall materials (carriers) besides the process conditions' effects on the encapsulation effectiveness and the particle size of the encapsulated bioactive compounds have been discussed. The encapsulation of these compounds ameliorates the quality of the stored meat products by further delaying in microflora growth and lipid/protein oxidation. Therefore, the innovative technologies for plant active compounds encapsulation offer a prospective alternative for natural preservation development in the meat industry.

Strategies of confining green tea catechin compounds in nano-biopolymeric matrices: A review

Catechins are polyphenolic compounds which abundantly occur in the plants, especially tea leaves. They are widely used in nutraceutical and pharmaceutical formulations due to their capability of lowering the risk of developing various diseases. Nevertheless, low stability, loss of antioxidant and antimicrobial activities hinder the direct application of catechins in food formulations. To surmount this pervasive challenge, bioactive ingredients should be entrapped in a biopolymeric matrix. Thus, nanoencapsulation technology would be an appropriate strategy to improve the stability of these bioactive compounds and to protect them against degradation. Among different types of nanocarriers, biopolymer-based nanovehicles has captured a lot of attention in both industry and academia due to their safety and biocompatibility. This revision enlarges upon the various types of biopolymeric nanostructures used for accommodation of catechins, namely nanogels, nanotubes, nanofibers, nanoemulsions and nanoparticles. Last but not least, the applications of the entrapped catechins in the food industry are highlighted.