Identification and Molecular Mechanism of Novel Two-Way Immunomodulatory Peptides from Ovalbumin: In Vitro Cell Experiments, De Novo Sequencing, and Molecular Docking.

The purpose of this study was to identify ovalbumin-derived immunomodulatory peptides by in vitro cell experiments, de novo sequencing, and molecular docking. Ovalbumin hydrolysates were prepared by two enzymes (alkaline protease and papain) individually, sequentially, or simultaneously, respectively. The simultaneous enzymatic hydrolysate (OVAH) had a high degree of hydrolysis (38.12 ± 0.48%) and exhibited immune-enhancing and anti-inflammatory activities. A total of 160 peptides were identified by LC-MS/MS in OVAH. Three novel peptides NVMEERKIK, ADQARELINS, and WEKAFKDE bound to TLR4-MD2 through hydrogen bonds and hydrophobic interactions with high binding affinity and binding energies of -181.40, -178.03, and -168.12 kcal/mol, respectively. These three peptides were synthesized and validated for two-way immunomodulatory activity. NVMEERKIK exhibiting the strongest immunomodulatory activity, increased NO and TNF-α levels by 128.69 and 38.01%, respectively, in normal RAW264.7 cells and reduced NO and TNF-α levels by 27.31 and 39.13%, respectively, in lipopolysaccharide-induced inflammatory RAW264.7 cells. Overall, this study first revealed that ovalbumin could be used as an immunomodulatory source for controlling inflammatory factor secretion.

Promoting effect of phosvitin in the mineralization of eggshell inner membrane with the application in osteogenic induction scaffold.

Exploring affordable and easily prepared inorganic-organic hybrid membrane materials has attracted a great interest in the bone repair field. This study is based on biomimetic mineralization technique to study the role of phosvitin (PV) in the mineralized process of eggshell inner membrane. Results showed that PV promoted the formation of hydroxyapatite on the eggshell inner membrane surface, and the phosvitin content in the simulated body fluid was decreased during the mineralization process. Besides, in vitro preosteoblast experiments indicated that mineralized membrane with PV exhibited more conducive to cell proliferation and differentiation than that mineralized membrane without PV. Interestingly, with the increase of mineralization time, the stimulating ability of mineralized membranes with PV on adhesion, proliferation, alkaline phosphatase activity and collagen type I content gradually improved. In summary, the eggshell inner membrane composites mineralized with PV obtained by biomimetic mineralization might be potential scaffold materials for bone repair.

The inhibitory effect of ovomucoid from egg white on biofilm formation by Streptococcus mutans.

BACKGROUND: Streptococcus mutans, the main pathogen associated with tooth decay, forms cariogenic biofilms on tooth surfaces. Therefore, controlling oral biofilm helps prevent dental caries. Hen's egg is a nutrient-dense food, and egg white is a good source of protein. Ovomucoid is one of the major proteins in egg white, with a 28 kDa molecular weight. The present study aimed to investigate the inhibitory effects of ovomucoid on the biofilm formation of S. mutans by suppressing virulence factors, including bacterial adherence, cellular aggregation and exopolysaccharide (EPS) production. RESULTS: Crystal violet staining showed that biofilm formation by S. mutans was inhibited by ovomucoid at 0.25-1 mg mL-1 levels. Field emission scanning electron microscopy also confirmed this inhibition. In addition, ovomucoid reduced mature biofilm, water-insoluble EPS synthesis and the metabolic activity of bacterial cells in the biofilm. The bacterial adhesion and aggregation abilities of S. mutans were also decreased in the presence of ovomucoid. Ovomucoid downregulated the expression of comDE and vicR genes involved in the two-component signal transduction system and gtfA and ftf genes involved in EPS production. CONCLUSION: Ovomucoid has the potential for use as an anti-biofilm agent for dental caries treatment because of its inhibitory effects on the virulence factors of S. mutans. © 2023 Society of Chemical Industry.

The elastase and melanogenesis inhibitory and anti-inflammatory activities of phosvitin phosphopeptides produced using high-temperature and mild-pressure (HTMP) pretreatment and enzyme hydrolysis combinations.

This study aimed to determine the skin protective effect of egg yolk phosvitin phosphopeptides (PPPs). Phosvitin was separated from the egg yolk, and PPPs were produced using high-temperature and mild-pressure (HTMP) pretreatment and enzyme-sterilization hydrolysis combinations. The elastase and melanogenesis inhibitory activities and anti-inflammatory effects of egg yolk PPPs were determined. All PPPs significantly inhibited elastase activity, but the PPPs prepared with HTMP pretreatment and trypsin-sterilization (HTMP-T-S) combination suppressed the tyrosinase activity the most. PPPs (3 mg/mL) inhibited the α-melanocyte-stimulating hormone-induced melanin production in B16F10 melanoma cells by 31.18 to 38.58%. In addition, PPPs effectively inhibited nitric oxide (NO) production in the LPS (lipopolysaccharide)-stimulated RAW 264.7 macrophages, and the PPPs from HTMP-T-S exhibited the highest inhibitory activity. The protein expressions of pro-inflammatory enzymes, inducible nitric oxide synthase, and cyclooxygenase-2 were down-regulated by the PPPs from the HTMP-T-S. Therefore, PPPs could be used as an anti-melanogenic, anti-elastase, and anti-inflammatory agent for humans and skin care products.

Comparison of Functional Properties of Blood Plasma Collected from Black Goat and Hanwoo Cattle.

Slaughterhouse blood is a by-product of animal slaughter that can be a good source of animal protein. This research purposed to examine the functional qualities of the blood plasma from Hanwoo cattle, black goat, and their hydrolysates. Part of the plasma was hydrolyzed with proteolytic enzymes (Bacillus protease, papain, thermolysin, elastase, and α-chymotrypsin) to yield bioactive peptides under optimum conditions. The levels of hydrolysates were evaluated by 15% sodium dodecyl sulfate polyacrylamide gel electrophoresis. The antioxidant, metal-chelating, and angiotensin I-converting enzyme (ACE) inhibitory properties of intact blood plasma and selected hydrolysates were investigated. Accordingly, two plasma hydrolysates by protease (pH 6.5/55°C/3 h) and thermolysin (pH 7.5/37°C/3-6 h) were selected for analysis of their functional properties. In the oil model system, only goat blood plasma had lower levels of thiobarbituric acid reactive substances than the control. The diphenyl picrylhydrazyl radical scavenging activity was higher in cattle and goat plasma than in proteolytic hydrolysates. Ironchelating activities increased after proteolytic degradation except for protease-treated cattle blood. Copper-chelating activity was excellent in all test samples except for the original bovine plasma. As for ACE inhibition, only non-hydrolyzed goat plasma and its hydrolysates by thermolysin showed ACE inhibitory activity (9.86±5.03% and 21.77±3.74%). In conclusion, goat plasma without hydrolyzation and its hydrolysates can be a good source of bioactive compounds with functional characteristics, whereas cattle plasma has a relatively low value. Further studies on the molecular structure of these compounds are needed with more suitable enzyme combinations.

Co-encapsulation of fish oil with essential oils and lutein/curcumin to increase the oxidative stability of fish oil powder.

The oxidation-resistant and multi-functional fish oil powders were produced by co-encapsulating fish oil with essential oils, lutein, and curcumin. The ovalbumin/alginate complex was used as the wall, and the wall-to-oil ratio was fixed at 1:1 based on yield, oil recovery, and internalization efficiency (IE). Surface oil was removed to better understand the characteristics of the fish oil powders. Scanning electron microscopy (SEM) results indicated that the freeze-dried fish oil powders had irregular shapes with visible pores on the surface. Covalent bonds and electrostatic interactions within the ovalbumin/alginate complex were detected through FTIR. The garlic essential oil-added sample showed the strongest oxidative stability throughout the storage period (30 days). This work showed that fish oil had been encapsulated successfully and multi-functional fish oil powders could be produced by dissolving lipophilic bioactive compounds in fish oil before encapsulation.

Hatched Eggshell Membrane Can Be a Novel Source of Antioxidant Hydrolysates to Protect against H2O2-Induced Oxidative Stress in Human Chondrocytes.

Natural antioxidants derived from agricultural by-products have great promise and ecological advantages in the treatment of oxidative stress-related diseases. The eggshell membrane (ESM) from hatched eggs, i.e., the hatched ESM, is a globally abundant agricultural byproduct, and its high-value utilization has been rarely studied compared to the well-studied ESM from fresh eggs. In this research, we systematically characterized the hatched ESM as a novel source of antioxidant hydrolysates and explored their potential role in H2O2-induced human chondrocytes. The results showed that the hatched ESM is a protein-rich fibrous mesh material with a significantly different structure and composition from those of fresh ESM. Enzymatic hydrolysis of hatched ESM can produce antioxidant hydrolysates rich in low molecular weight (MW) peptides, which mainly derived from the Lysyl oxidase homolog by Nano-LC-MS/MS analysis. The peptide fraction with MW < 3 kDa (HEMH-I) exhibited the highest DPPH radical scavenging, Fe2+-chelating, and Fe3+-reducing abilities. In H2O2-induced human SW1353 chondrocytes, HEMH-I treatment significantly increased the cell viability and ameliorated oxidative stress, inflammatory response, and cartilage matrix degradation by reducing the level of ROS, matrix metalloprotease 3 (MMP3), MMP13, and IL-6, and by promoting the expression of SOD and type II collagen, potentially through activating the cellular Keap1/Nrf2/HO-1 pathway. This study provides a theoretical basis for the value-added application of hatched ESM waste to produce antioxidant hydrolysates and indicates their potential as functional food and pharmaceuticals.

A basis for IgY-themed functional foods: Digestion profile of oral yolk immunoglobulin (IgY) by INFOGEST static digestion model.

Although yolk immunoglobulin (IgY) has been reported its functions of antiviral, antibacterial, energy balancing, and gut microbiota regulating, its gastrointestinal digestion process and the digestion products have not been studied, which is of great significance for the development of IgY-themed functional foods. This work investigated the digestion behaviors of oral IgY by static digestion simulation in vitro. IgY showed low digestibility (23.97%) in the gastric phase but was highly digestible (89.49% digestibility) in the initial intestinal phase. The entire digestion involved IgY aggregation, degradation, re-aggregation, and gradual decomposition into small pieces (by dynamic light scattering). These results indicated that IgY was impressionable, unstable and changeful in gastrointestinal environment, which might impair the bioactive function of IgY. Over 6 peptides (such as RGFK, TVPSGASTK, VPAATASPR) and 21 amino acids were detected, including 6 essential amino acids (methionine, isoleucine, leucine, histidine, tryptophan, and lysine), suggesting that IgY could be involved in human health regulation as active peptides or as rich sources of amino acids in addition to its own bioactive functions. The digestion kinetic curve confirmed that IgY did not reach its maximum digestion at the end of simulation of intestinal phase, implying the incomplete utilization of IgY. This study provides valuable details of oral IgY for development as active ingredients of a functional food, contributing to boosting the egg industry and improving human health.

Interaction research of resveratrol and phosvitin based on fluorescence spectroscopy and molecular docking analysis.

Phosvitin (PV) is the main phosphoprotein in egg yolk, with the highest degree of phosphorylation known in nature. The PV and resveratrol (Res) can form a complex, thus effectively improve the solubility of Res. In this work, the interaction between Res and PV was investigated by the fluorescence spectroscopy and molecular docking. The fluorescence emission intensity of PV became weak along with a red shift when it interacted with Res and the antioxidant activity was enhanced. The quenching constants of the interaction systems were 1.12×104  M-1 and 9.40×103  M-1 at 25°C and 35°C, respectively, which indicated the presence of static quenching phenomena between them. The binding constant was 1.80×104  M-1 , and the number of corresponding binding sites was approximately equal to one. The thermodynamic results revealed the combination was spontaneous, and the change of enthalpy and entropy was ∆H = 53.50 kJ/mol, ∆S = 261.00 J/mol·K, respectively. It indicated that the interaction forces between Res and PV were mainly hydrophobic interaction and hydrogen bonding. Molecular docking showed the binding mode, which was consistent with the experiment results. The research on the interaction between Res and PV provided theoretical guidance for the application of Res in food. PRACTICAL APPLICATION: PV is the most highly phosphorylated protein in nature and has pro-calcium absorption effects. Res is a polyphenol with strong antioxidant and anti-inflammatory activity, but its poor solubility limits its application. In this study, the solubility of Res was considerably enhanced by compounding Res and PV, and the antioxidant activity of Res was well retained. It increases the value of Res in food and other applications and opens up new possibilities for processing and utilization of PV.

Egg yolk lipids: separation, characterization, and utilization.

Egg yolk contains very high levels of lipids, which comprise 33% of whole egg yolk. Although triglyceride is the main lipid, egg yolk is the richest source of phospholipids and cholesterol in nature. The egg yolk phospholipids have a unique composition with high levels of phosphatidylcholine followed by phosphatidylethanolamine, sphingomyelin, plasmalogen, and phosphatidylinositol. All the egg yolk lipids are embedded inside the HDL and LDL micelles or granular particles. Egg yolk lipids can be easily extracted using solvents or supercritical extraction methods but their commercial applications of egg yolk lipids are limited. Egg yolk lipids have excellent potential as a food ingredient or cosmeceutical, pharmaceutical, and nutraceutical agents because they have excellent functional and biological characteristics. This review summarizes the current knowledge on egg yolk lipids' extraction methods and functions and discusses their current and future use, which will be important to increase the use and value of the egg.

Immunomodulatory effects of chicken soups prepared with the native cage-free chickens and the commercial caged broilers.

The objective of this study was to compare the immunomodulatory effects of the chicken soups prepared with the native free-range chickens and the commercial caged broilers in the immunosuppressive mice. The immunosuppressive mice model was established by the intraperitoneal injection of 100 mg of cyclophosphamide (CTX) per kg body weight. The powders of Gushi Chicken Soup (GCS), Honglashan Chicken Soup (HCS), and Cobb Broiler Soup (CBS) were prepared by high-pressure stewing followed by spray drying. The chicken soups' nutrient content and the effects of three chicken soups on the body weight, organ index, blood index, and serum cytokine and immunoglobulin contents in the immunosuppressive mice were determined. The three chicken soups promoted the recovery of immunosuppressive mice, but the expression mechanisms were different. The GCS was more effective than the HCS and CBS in restoring blood index, promoting cytokine secretion, and increasing immunoglobulin content (P < 0.05). The HCS stimulated the Th1-type immune response and promoted immunoglobulin secretion (P < 0.05), while the CBS increased the production of CD4+ and promoted the T-cell functions better than other soups (P < 0.05). Although soups from the native free-range chickens and the commercial caged broilers showed distinctly different mechanisms in promoting immunity, both could be used as potential immunomodulators.

Plant- and Animal-Based Antioxidants' Structure, Efficacy, Mechanisms, and Applications: A Review.

Antioxidants are compounds that normally prevent lipid and protein oxidation. They play a major role in preventing many adverse conditions in the human body, including inflammation and cancer. Synthetic antioxidants are widely used in the food industry to prevent the production of adverse compounds that harm humans. However, plant- and animal-based antioxidants are more appealing to consumers than synthetic antioxidants. Plant-based antioxidants are mainly phenolic compounds, carotenoids, and vitamins, while animal-based antioxidants are mainly whole protein or the peptides of meat, fish, egg, milk, and plant proteins. Plant-based antioxidants mainly consist of aromatic rings, while animal-based antioxidants mainly consist of amino acids. The phenolic compounds and peptides act differently in preventing oxidation and can be used in the food and pharmaceutical industries. Therefore, compared with animal-based antioxidants, plant-based compounds are more practical in the food industry. Even though plant-based antioxidant compounds are good sources of antioxidants, animal-based peptides (individual peptides) cannot be considered antioxidant compounds to add to food. However, they can be considered an ingredient that will enhance the antioxidant capacity. This review mainly compares plant- and animal-based antioxidants' structure, efficacy, mechanisms, and applications.

Improved immune-enhancing activity of egg white protein ovotransferrin after enzyme hydrolysis.

Ovotransferrin (OTF), an egg protein known as transferrin family protein, possess strong antimicrobial and antioxidant activity. This is because OTF has two iron binding sites, so it has a strong metal chelating ability. The present study aimed to evaluate the improved immune-enhancing activities of OTF hydrolysates produced using bromelain, pancreatin, and papain. The effects of OTF hydrolysates on the production and secretion of pro-inflammatory mediators in RAW 264.7 macrophages were confirmed. The production of nitric oxide (NO) was evaluated using Griess reagent and the expression of inducible nitric oxide synthase (iNOS) were evaluated using quantitative real-time polymerase chain reaction (PCR). And the production of pro-inflammatory cytokines (tumor necrosis factor [TNF]-α and interleukin [IL]-6) and the phagocytic activity of macrophages were evaluated using an ELISA assay and neutral red uptake assay, respectively. All OTF hydrolysates enhanced NO production by increasing iNOS mRNA expression. Treating RAW 264.7 macrophages with OTF hydrolysates increased the production of pro-inflammatory cytokines and the phagocytic activity. The production of NO and pro-inflammatory cytokines induced by OTF hydrolysates was inhibited by the addition of specific mitogen-activated protein kinase (MAPK) inhibitors. In conclusion, results indicated that all OTF hydrolysates activated RAW 264.7 macrophages by activating MAPK signaling pathway.

Analytical Methods for Lipid Oxidation and Antioxidant Capacity in Food Systems.

Lipid oxidation is the most crucial quality parameter in foods. Many methods were developed to determine the level of oxidation and antioxidant activity. This review compares the methods used to determine lipid oxidation and antioxidant capacity in foods. Lipid oxidation methods developed are based on the direct or indirect measurement of produced primary or secondary oxidation substances. Peroxide values and conjugated diene methods determine the primary oxidative products of lipid oxidation and are commonly used for plant oils and high-fat products. 2-Thiobarbituric acid-reactive substances and chromatographic methods are used to determine the secondary products of oxidation and are suitable for meat and meat-based products. The fluorometric and sensory analyses are indirect methods. The antioxidant capacity of additives is determined indirectly using the lipid oxidation methods mentioned above or directly based on the free-radical scavenging activity of the antioxidant compounds. Each lipid oxidation and antioxidant capacity methods use different approaches, and one method cannot be used for all foods. Therefore, selecting proper methods for specific foods is essential for accurately evaluating lipid oxidation or antioxidant capacity.

Fab Fragment of Immunoglobulin Y Modulates NF-κB and MAPK Signaling through TLR4 and αVß3 Integrin and Inhibits the Inflammatory Effect on R264.7 Macrophages.

High-purity Fab fragment and immunoglobulin Y (IgY) were prepared to evaluate their anti-inflammatory activity in the lipopolysaccharide (LPS)-induced Raw 264.7 macrophage system. Compared with IgY, the Fab fragment possessed a greater potency in inhibiting the inflammation by nitric oxide (NO)/inducible nitric oxide synthase (iNOS) and prostaglandin-E2 (PGE2)/cyclooxygenase-2 (COX-2) pathways. The Fab fragment attenuated the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) to 38.07 ± 1.86-48.39 ± 11.33 pg/mL (63.1-71.0% inhibition), 31.59 ± 3.91-38.08 ± 4.44 pg/mL (72.4-77.1% inhibition), and 20.62 ± 0.46-21.91 ± 0.65 pg/mL (50-53% inhibition), respectively. Additionally, the Fab fragment significantly inhibited the translocation of nuclear transcription factor-κB (NF-κB) p65 and the phosphorylation of mitogen-activated protein kinase (MAPK) proteins, including ERK1/2 (41.5/33.2%), JNK1/2 (44.2/39.6%), and p38 (42.2%). The Fab fragment could be internalized into cells, and the pretreatment of RAW 264.7 macrophages with the Fab fragment reduced the mRNA expression of the Toll-like receptor (TLR4, 32.7-44.4% inhibition) and αVß3 integrin (76.1% inhibition). In conclusion, Fab fragments regulated the TLR4 and αVß3 integrin-mediated inflammatory processes by blocking the NF-κB and MAPKs pathways in the LPS-induced RAW 264.7 macrophage system.

Enzymatic Hydrolysis of Ovotransferrin and the Functional Properties of Its Hydrolysates.

Bioactive peptides have great potentials as nutraceutical and pharmaceutical agents that can improve human health. The objectives of this research were to produce functional peptides from ovotransferrin, a major egg white protein, using single enzyme treatments, and to analyze the properties of the hydrolysates produced. Lyophilized ovotransferrin was dissolved in distilled water at 20 mg/mL, treated with protease, elastase, papain, trypsin, or α-chymotrypsin at 1% (w/v) level of substrate, and incubated for 0-24 h at the optimal temperature of each enzyme (protease 55°C, papain 37°C, elastase 25°C, trypsin 37°C, α-chymotrypsin 37°C). The hydrolysates were tested for antioxidant, metal-chelating, and antimicrobial activities. Protease, papain, trypsin, and α-chymotrypsin hydrolyzed ovotransferrin relatively well after 3 h of incubation, but it took 24 h with elastase to reach a similar degree of hydrolysis. The hydrolysates obtained after 3 h of incubation with protease, papain, trypsin, α-chymotrypsin, and after 24 h with elastase were selected as the best products to analyze their functional properties. None of the hydrolysates exhibited antioxidant properties in the oil emulsion nor antimicrobial property at 20 mg/mL concentration. However, ovotransferrin with α-chymotrypsin and with elastase had higher Fe3+-chelating activities (1.06±0.88%, 1.25±0.24%) than the native ovotransferrin (0.46±0.60%). Overall, the results indicated that the single-enzyme treatments of ovotransferrin were not effective to produce peptides with antioxidant, antimicrobial, or Fe3+-chelating activity. Further research on the effects of enzyme combinations may be needed.

Functional properties of ovotransferrin from chicken egg white and its derived peptides: a review.

With emerging trends in the food and pharmaceutical industries, potential applications of egg-derived bioactive compounds were recognized. Ovotransferrin is a major egg white functional protein responsible for multiple bioactivities. The objectives of this review are to provide scientific evidence of the functional properties of chicken ovotransferrin and its derived peptides and to identify future research approaches and applications. Various easy, economical, and non-toxic methods have been reported to produce ovotransferrin with high yield and purity, and chemical and enzymatic approaches have been employed to release bioactive peptides. The native ovotransferrin is known to have antimicrobial, antioxidant, anticancer, and immunomodulatory activities. The peptides produced from ovotransferrin also are reported to have antioxidant, antimicrobial, antihypertensive, and anticancer properties. However, little or no application of these compounds in the food and pharmaceutical areas is available yet. Therefore, the practical application of OTF in nutraceutical and pharmaceutical areas are among the emerging areas of research.

Phosvitin phosphopeptides produced by pressurized hea-trypsin hydrolysis promote the differentiation and mineralization of MC3T3-E1 cells via the OPG/RANKL signaling pathways.

Phosvitin (PV) from egg yolk is an excellent substrate for the production of phosphopeptides, which have a strong calcium chelating capacity and promoting calcium absorption and bone mineralization. This study investigated the effect of PV hydrolysates produced using a effective preparation method (high temperature (121°C) and mild pressure (0.1 MPa), HTMP) or HTMP pretreatment and trypsin hydrolysis combination (HTMP-PV18) on the physiology of an osteoblast MC3T3-E1 cells line. The proliferation, apoptosis, and differentiation of MC3T3-E1 cells were analyzed using the CCK-8, flow cytometry, and RT-PCR reactions, respectively. Both the HTMP-PV and HTMP-PV18 increased the proliferation, and inhibited the apoptosis of MC3T3-E1 cells significantly. The HTMP-PV increased the proliferation of MC3T3-E1 cells by 147.12 ± 2.11% and the HTMP-PV18 by 136.43 ± 4.51%. In addition, the HTMP-PV and HTMP-PV18 effectively promoted the expression of genes related to the OPG/RANKL signaling channel during cell differentiation. This indicated that both the HTMP-PV and HTMP-PV18 have the potential to promote bone mineralization by improving the proliferation and differentiation of osteoblastic cells.

Anti-Biofilm Effect of Egg Yolk Phosvitin by Inhibition of Biomass Production and Adherence Activity against Streptococcus mutans.

The formation of biofilms on the enamel surface of teeth by Streptococcus mutans is an important step in dental plaque formation, demineralization, and early caries because the biofilm is where other bacteria involved in dental caries attach, grow, and proliferate. The objectives of this study were to determine the effect of phosvitin (PSV) on the biofilm formation, exopolysaccharides (EPS) production, adherence activity of S. mutans, and the expression of genes related to the compounds essential for biofilm formation (quorum-sensing inducers and components of biofilm matrix) by S. mutans. PSV significantly reduced the biofilm-forming activity of S. mutans and increased the degradation of preformed biofilms by S. mutans. PSV inhibited the adherence activity of S. mutans by 31.9%-33.6%, and the production of EPS by 62%-65% depending upon the strains and the amount of PSV added. The expressions of genes regulating the production of EPS and the quorum-sensing-inducers (gtfA, gtfD, ftf, relA, vicR, brpA, and comDE) in all S. mutans strains were down-regulated by PSV, but gtfB was down-regulated only in S. mutans KCTC 5316. Therefore, the anti-biofilm-forming activity of PSV was accomplished through the inhibition of biofilm formation, adherence activity, and the production of quorum-sensing inducers and EPS by S. mutans.

Ovalbumin Hydrolysates Inhibit Nitric Oxide Production in LPS-induced RAW 264.7 Macrophages.

In this study, ovalbumin (OVA) hydrolysates were prepared using various proteolytic enzymes and the anti-inflammatory activities of the hydrolysates were determined. Also, the potential application of OVA as a functional food material was discussed. The effect of OVA hydrolysates on the inhibition of nitric oxide (NO) production was evaluated via the Griess reaction, and their effects on the expression of inducible NO synthase (inducible nitric oxide synthase, iNOS) were assessed using the quantitative real-time PCR and Western blotting. To determine the mechanism by which OVA hydrolysates activate macrophages, pathways associated with the mitogen-activated protein kinase (MAPK) signaling were evaluated. When the OVA hydrolysates were added to RAW 264.7 cells without lipopolysaccharide (LPS) stimulation, they did not affect the production of NO. However, both the OVA-Protex 6L hydrolysate (OHPT) and OVA-trypsin hydrolysate (OHT) inhibited NO production dose-dependently in LPS- stimulated RAW 264.7 cells. Especially, OHT showed a strong NO-inhibitory activity (62.35% at 2 mg/mL) and suppressed iNOS production and the mRNA expression for iNOS (p<0.05). Also, OHT treatment decreased the phosphorylation levels of Jun amino-terminal kinases (JNK) and extracellular signal-regulated kinases (ERK) in the MAPK signaling pathway. These findings suggested that OVA hydrolysates could be used as an anti-inflammatory agent that prevent the overproduction of NO.