Enzymatic upcycling of wild-simulated ginseng leaves for enhancing biological activities and compound K.

Compound K (CK), a ginsenoside with high bioavailability, is present at low levels in wild-simulated ginseng leaves (WSGL). WSGL contains the CK precursors, Rd and F2, in amounts up to 26.4 ± 0.4 and 24.1 ± 1.9 mg/g extract, respectively. In this study, CK production in WGSL reached 25.9 ± 1.0 mg/g extract following treatment with Viscozyme, Celluclast 1.5 L, Pectinex Ultra SP-L, and their combination. The antioxidant activities indicated by oxygen radical absorbance capacity, ferric reducing antioxidant power, and ABTS- and DPPH radical scavenging activity of enzyme-treated WSGL were enhanced 1.69-, 2.51-, 2.88-, and 1.80-fold, respectively, compared to non-treated WSGL. Furthermore, the CK-enriched WSGL demonstrated a 1.94-fold decrease in SA-ß-galactosidase expression in human dermal fibroblasts and a 3.8-fold enhancement of inhibition of nitric oxide release in lipopolysaccharide-induced RAW 264.7 cells relative to non-treated WSGL. Consequently, WSGL subjected to enzymatic upcycling has potential as a functional material in the food and pharmaceutical industries.

Enhancement of debitterness, water-solubility, and neuroprotective effects of naringin by transglucosylation.

Naringin found in citrus fruits is a flavanone glycoside with numerous biological activities. However, the bitterness, low water-solubility, and low bioavailability of naringin are the main issues limiting its use in the pharmaceutical and nutraceutical industries. Herein, a glucansucrase from isolated Leuconostoc citreum NY87 was used for trans-α-glucosylattion of naringin by using sucrose as substrate. Two naringin glucosides (O-α-D-glucosyl-(1'''' → 6″) naringin (compound 1) and 4'-O-α-D-glucosyl naringin (compound 2)) were purified and determined their structures by nuclear magnetic resonance. The optimization condition for the synthesis of compound 1 was obtained at 10 mM naringin, 200 mM sucrose, and 337.5 mU/mL at 28 °C for 24 h by response surface methodology method. Compound 1 and compound 2 showed 1896- and 3272 times higher water solubility than naringin. Furthermore, the bitterness via the human bitter taste receptor TAS2R39 displayed that compound 1 was reduced 2.9 times bitterness compared with naringin, while compound 2 did not express bitterness at 1 mM. Both compounds expressed higher neuroprotective effects than naringin on human neuroblastoma SH-SY5Y cells treated with 5 mM scopolamine based on cell viability and cortisol content. Compound 1 reduced acetylcholinesterase activity more than naringin and compound 2. These results indicate that naringin glucosides could be utilized as functional material in the nutraceutical and pharmaceutical industries. KEY POINTS: • A novel O-α-D-glucosyl-(1 → 6) naringin was synthesized using glucansucrase from L. citreum NY87. • Naringin glucosides improved water-solubility and neuroprotective effects on SH-SY5Y cells. • Naringin glucosides showed a decrease in bitterness on bitter taste receptor 39.

A practical approach to producing isomaltomegalosaccharide using dextran dextrinase from Gluconobacter oxydans ATCC 11894.

Dextran dextrinase (DDase) catalyzes formation of the polysaccharide dextran from maltodextrin. During the synthesis of dextran, DDase also generates the beneficial material isomaltomegalosaccharide (IMS). The term megalosaccharide is used for a saccharide having DP = 10-100 or 10-200 (DP, degree of polymerization). IMS is a chimeric glucosaccharide comprising α-(1 → 6)- and α-(1 → 4)-linked portions at the nonreducing and reducing ends, respectively, in which the α-(1 → 4)-glucosyl portion originates from maltodextrin of the substrate. In this study, IMS was produced by a practical approach using extracellular DDase (DDext) or cell surface DDase (DDsur) of Gluconobacter oxydans ATCC 11894. DDsur was the original form, so we prepared DDext via secretion from intact cells by incubating with 0.5% G6/G7 (maltohexaose/maltoheptaose); this was followed by generation of IMS from various concentrations of G6/G7 substrate at different temperatures for 96 h. However, IMS synthesis by DDext was limited by insufficient formation of α-(1 → 6)-glucosidic linkages, suggesting that DDase also catalyzes elongation of α-(1 → 4)-glucosyl chain. For production of IMS using DDsur, intact cells bearing DDsur were directly incubated with 20% G6/G7 at 45 °C by optimizing conditions such as cell concentration and agitation efficiency, which resulted in generation of IMS (average DP = 14.7) with 61% α-(1 → 6)-glucosyl content in 51% yield. Increases in substrate concentration and agitation efficiency were found to decrease dextran formation and increase IMS production, which improved the reaction conditions for DDext. Under modified conditions (20% G6/G7, agitation speed of 100 rpm at 45 °C), DDext produced IMS (average DP = 14.5) with 65% α-(1 → 6)-glucosyl content in a good yield of 87%. KEY POINTS: • Beneficial IMS was produced using thermostabilized DDase. • Optimum conditions for reduced dextran formation were successfully determined. • A practical approach was established to provide IMS with a great yield of 87%.

Selected Applications of Chitosan Composites.

Chitosan is one of the emerging materials for various applications. The most intensive studies have focused on its use as a biomaterial and for biomedical, cosmetic, and packaging systems. The research on biodegradable food packaging systems over conventional non-biodegradable packaging systems has gained much importance in the last decade. The deacetylation of chitin, a polysaccharide mainly obtained from crustaceans and shrimp shells, yields chitosan. The deacetylation process of chitin leads to the generation of primary amino groups. The functional activity of chitosan is generally owed to this amino group, which imparts inherent antioxidant and antimicrobial activity to the chitosan. Further, since chitosan is a naturally derived polymer, it is biodegradable and safe for human consumption. Food-focused researchers are exploiting the properties of chitosan to develop biodegradable food packaging systems. However, the properties of packaging systems using chitosan can be improved by adding different additives or blending chitosan with other polymers. In this review, we report on the different properties of chitosan that make it suitable for food packaging applications, various methods to develop chitosan-based packaging films, and finally, the applications of chitosan in developing multifunctional food packaging materials. Here we present a short overview of the chitosan-based nanocomposites, beginning with principal properties, selected preparation techniques, and finally, selected current research.

The Inhibitory Effects of Plant Derivate Polyphenols on the Main Protease of SARS Coronavirus 2 and Their Structure-Activity Relationship.

The main protease (Mpro) is a major protease having an important role in viral replication of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the novel coronavirus that caused the pandemic of 2020. Here, active Mpro was obtained as a 34.5 kDa protein by overexpression in E. coli BL21 (DE3). The optimal pH and temperature of Mpro were 7.5 and 37 °C, respectively. Mpro displayed a Km value of 16 µM with Dabcyl-KTSAVLQ↓SGFRKME-Edans. Black garlic extract and 49 polyphenols were studied for their inhibitory effects on purified Mpro. The IC50 values were 137 µg/mL for black garlic extract and 9-197 µM for 15 polyphenols. The mixtures of tannic acid with puerarin, daidzein, and/or myricetin enhanced the inhibitory effects on Mpro. The structure-activity relationship of these polyphenols revealed that the hydroxyl group in C3', C4', C5' in the B-ring, C3 in the C-ring, C7 in A-ring, the double bond between C2 and C3 in the C-ring, and glycosylation at C8 in the A-ring contributed to inhibitory effects of flavonoids on Mpro.

Fermented Wild Ginseng by Rhizopus oligosporus Improved l-Carnitine and Ginsenoside Contents.

We conducted this study to investigate the beneficial effects of Rhizopus oligosporus fermentation of wild ginseng on ginsenosides, l-carnitine contents and its biological activity. The Rhizopus oligosporus fermentation of wild ginseng was carried out at 30 °C for between 1 and 14 days. Fourteen ginsenosides and l-carnitine were analyzed in the fermented wild ginseng by the ultra high pressure liquid chromatography-mass spectrometry (UPLC-MS) system. Our results showed that the total amount of ginsenosides in ginseng increased from 3,274 to 5,573 mg/kg after 14 days of fermentation. Among the 14 ginsenosides tested, the amounts of 13 ginsenosides (Rg1, Rb2, Rb3, Rc, Rd, Re, Rf, Rg2, Rg3, Rh1, compound K, F1 and F2) increased, whereas ginsenoside Rb1 decreased, during the fermentation. Furthermore, l-carnitine (630 mg/kg) was newly synthesized in fermented ginseng extract after 14 days. In addition, both total phenol contents and DPPH radical scavenging activities showed an increase in the fermented ginseng with respect to non-fermented ginseng. These results show that the fermentation process reduced the cytotoxicity of wild ginseng against RAW264.7 cells. Both wild and fermented wild ginseng showed anti-inflammatory activity via inhibition of nitric oxide synthesis in RAW264.7 murine macrophage cells.

Anti-cariogenic Characteristics of Rubusoside.

Streptococcus mutans plays an important role in the development of dental caries in humans by synthesizing adhesive insoluble glucans from sucrose by mutansucrase activity. To explore the anti-cariogenic characteristics of rubusoside (Ru), a natural sweetener component in Rubus suavissimus S. Lee (Rosaceae), we investigated the inhibitory effect of Ru against the activity of mutansucrase and the growth of Streptococcus mutans. Ru (50 mM) showed 97% inhibitory activity against 0.1 U/mL mutansucrase of S. mutans with 500 mM sucrose. It showed competitive inhibition with a K i value of 1.1 ± 0.2 mM and IC50 of 2.3 mM. Its inhibition activity was due to hydrophobic and hydrogen bonding interactions based on molecular docking analysis. Ru inhibited the growth of S. mutans as a bacteriostatic agent, with MIC and MBC values of 6 mM and 8 mM, respectively. In addition, Ru showed synergistic anti-bacterial activity when it was combined with curcumin. Therefore, Ru is a natural anti-cariogenic agent with anti-mutansucrase activity and antimicrobial activity against S. mutans. ELECTRONIC SUPPLEMENTARY MATERIAL ESM: The online version of this article (doi: 10.1007/s12257-018-0408-0) contains supplementary material, which is available to authorized users.

Decrease of insoluble glucan formation in Streptococcus mutans by co-cultivation with Enterococcus faecium T7 and glucanase addition.

OBJECTIVES: To develop preventive canine oral health bio-materials consisting of probiotics and glucanase to reduce insoluble glucan and volatile sulfur compound formation. RESULTS: Co-cultivation of Enterococcus faecium T7 with Streptococcus mutans at inoculation ratio of 3:1 (v/v) resulted in 25% reduction in the growth of Streptococcus mutans. Amounts of soluble and insoluble glucans produced by S. mutans were decreased to 70 and 55%, respectively. Insoluble glucan was decreased from 0.6 µg/ml in S. mutans culture to 0.03 µg/ml in S. mutans co-cultivated with E. faecium T7 in the presence of Lipomyces starkeyi glucanase. Volatile sulfur compound, a main component of halitosis produced by Fusobacteria nucleatum, was decreased by co-cultivating F. nucleatum with E. faecium. CONCLUSION: E. faecium and glucanase can be combined as potentially active ingredients of oral care products for pets by reducing plaque-forming bacteria growth and their by-products that cause cavity and periodontal disease.

Production of steviol from steviol glucosides using ß-glucosidase from a commercial pectinase, Sumizyme PX.

OBJECTIVE: To purify and characterize a specific enzyme from a commercial pectinase for the production of steviol from stevioside (Ste) without adding organic solvent and to improve steviol production. RESULTS: Commercial Sumizyme PX converted Ste to steviol with a yield of 98%. ß-Glucosidase from Sumizyme PX (ßglyPX) was purified in three steps with 12.5-fold purification and 51% yield. The specific activity of the purified ßglyPX was 141 U/mg. The molecular weight of ßglyPX was ~ 116 kDa on SDS-PAGE. Its optimum activity was at pH 3.5 and 65 °C. It was stable for 12 h up to 55 °C and for 24 h at pH 2-9.5. K m values of ßglyPX for pNPGal, oNPGlc, lactose, and Ste were 2.4, 0.7, 18, and 7.8 mM, respectively. The optimum conditions for steviol production were 55 °C, 900 U/ml, 80 mg Ste/ml, 12 h. CONCLUSION: ßglyPX contains great potential for industrial steviol production from Ste.

Hydrophilic Astragalin Galactoside Induces T Helper Type 1-Mediated Immune Responses via Dendritic Cells.

A flavonoid Astragalin (kaempferol-3-O-ß-d-glucopyranoside, Ast) has several biological activities including anti-oxidant, anti-HIV, and anti-allergic effects. Nonetheless, its insolubility in hydrophilic solvents imposes restrictions on its therapeutic applications. In this study, we investigated the effects of water-soluble astragalin-galactoside (kaempferol-3-O-ß-d-isomaltotrioside, Ast-Gal) on murine bone marrow-derived dendritic cell (DC) maturation and T helper (Th) cell-mediated immune responses. Ast-Gal significantly increased maturation and activation of DCs through the upregulation of surface markers, such as cluster of differentiation (CD)80, CD86, and Major histocompatibility complex (MHC) II in a dose-dependent manner, while Ast had little effects. Additionally, Ast-Gal-treated DCs markedly secreted immune-stimulating cytokines such as interleukin (IL)-1ß, IL-6, and IL-12. Importantly, Ast-Gal strongly increased expression of IL-12, a polarizing cytokine of Th1 cells. In a co-culture system of DCs and CD4⁺ T cells, Ast-Gal-treated DCs preferentially differentiates naïve CD4⁺ T cells into Th1 cells. The addition of neutralizing IL-12 monoclonal antibody (mAb) to cultures of Ast-Gal-treated DCs and CD4⁺ T cells significantly decreased interferon (IFN)-γ production, thereby indicating that Ast-Gal-stimulated DCs enhance the Th1 response through IL-12 production by DCs. Injection with Ast-Gal-treated DCs in mice increased IFN-γ-secreting Th1 cell population. Collectively, these findings indicate that hydrophilically modified astragalin can enhance Th1-mediated immune responses via DCs and point to a possible application of water-soluble astragalin-galactoside as an immune adjuvant.

Cytoprotective Effect of Epigallocatechin Gallate (EGCG)-5'-O-α-Glucopyranoside, a Novel EGCG Derivative.

Epigallocatechin gallate (EGCG) is a well-studied polyphenol with antioxidant effects. Since EGCG has low solubility and stability, many researchers have modified EGCG residues to ameliorate these problems. A novel EGCG derivative, EGCG-5'-O-α-glucopyranoside (EGCG-5'Glu), was synthesized, and its characteristics were investigated. EGCG-5'Glu showed antioxidant effects in cell and cell-free systems. Under SNP-derived radical exposure, EGCG-5'Glu decreased nitric oxide (NO) production, and recovered ROS-mediated cell viability. Moreover, EGCG-5'Glu regulated apoptotic pathways (caspases) and cell survival molecules (phosphoinositide 3-kinase (PI3K) and phosphoinositide-dependent kinase 1 (PDK1)). In another radical-induced condition, ultraviolet B (UVB) irradiation, EGCG-5'Glu protected cells from UVB and regulated the PI3K/PDK1/AKT pathway. Next, the proliferative effect of EGCG-5'Glu was examined. EGCG-5'Glu increased cell proliferation by modulating nuclear factor (NF)-κB activity. EGCG-5'Glu protects and repairs cells from external damage via its antioxidant effects. These results suggest that EGCG-5'Glu could be used as a cosmetics ingredient or dietary supplement.

Inhibitory effect of flavonoids against NS2B-NS3 protease of ZIKA virus and their structure activity relationship.

OBJECTIVES: To determine the inhibitory activities of flavonoids against NS2B-NS3 protease of ZIKA virus (ZIKV NS2B-NS3pro) expressed in Escherichia coli BL21 (DE3) and their structure activity relationship. RESULTS: ZIKV NS2B-NS3pro was expressed in E. coli BL21(DE3) as a 35 kDa protein. It had a K m of 26 µM with the fluorogenic peptide Dabcyl-KTSAVLQSGFRKME-Edan. The purified ZIKV NS2B-NS3pro was used for inhibition and kinetic assays to determine the activities of 22 polyphenol compounds. These polyphenol compounds at 100 µM inhibited the activity of ZIKV NS2B-NS3pro by 6.2-88%. Seven polyphenol compounds had IC50 ranging from 22 ± 0.2 to 112 ± 5.5 µM. Myricetin showed a mixed type inhibitory pattern against ZIKV NS2B-NS3pro protease. Its IC50 value was 22 ± 0.2 µM with a K i value of 8.9 ± 1.9 µM. CONCLUSION: The chemical structure of a polyphenol compound and its inhibitory activity against ZIKV NS2B-NS3pro can be explored to develop highly selective inhibitors against ZIKV NS2B-NS3pro.

The effect of fermented buckwheat on producing l-carnitine- and γ-aminobutyric acid (GABA)-enriched designer eggs.

BACKGROUND: The potential of fermented buckwheat as a feed additive was studied to increase l-carnitine and γ-aminobutyric acid (GABA) in designer eggs. Buckwheat contains high levels of lysine, methionine and glutamate, which are precursors for the synthesis of l-carnitine and GABA. Rhizopus oligosporus was used for the fermentation of buckwheat to produce l-carnitine and GABA that exert positive effects such as enhanced metabolism, antioxidant activities, immunity and blood pressure control. RESULTS: A novel analytical method for simultaneously detecting l-carnitine and GABA was developed using liquid chromatography/mass spectrometry (LC/MS) and LC/MS/MS. The fermented buckwheat extract contained 4 and 34 times more l-carnitine and GABA respectively compared with normal buckwheat. Compared with the control, the fermented buckwheat extract-fed group showed enriched l-carnitine (13.6%) and GABA (8.4%) in the yolk, though only l-carnitine was significantly different (P < 0.05). Egg production (9.4%), albumen weight (2.1%) and shell weight (5.8%) were significantly increased (P < 0.05). There was no significant difference in yolk weight, and total cholesterol (1.9%) and triglyceride (4.9%) in the yolk were lowered (P < 0.05). CONCLUSION: Fermented buckwheat as a feed additive has the potential to produce l-carnitine- and GABA-enriched designer eggs with enhanced nutrition and homeostasis. These designer eggs pose significant potential to be utilized in superfood production and supplement industries. © 2016 Society of Chemical Industry.

Anti-inflammatory effects of sucrose-derived oligosaccharides produced by a constitutive mutant L. mesenteroides B-512FMCM dextransucrase in high fat diet-fed mice.

Oligosaccharide (OS) is used as a sugar replacement as well as an ingredient in functional foods because of its beneficial effects, mainly on reducing calorie content and promoting intestinal health. By contrast, the effects of OS on inflammation are less well investigated. The purpose of this study was to investigate the effects of sucrose-derived OS on glucose control and inflammation in high fat (HF) diet-fed mice. Male C57BL6 mice were randomly assigned to six treatment groups (n = 10-14 mice per group): 1) lean control (CON), 2) HF control, 3) HF-low sucrose (LS, 100 mg/kg/day), 4) HF-high sucrose (HS, 1000 mg/kg/day), 5) HF-low OS (LOS, 100 mg/kg/day), and 6) HF-high OS (HOS, 1000 mg/kg/day). PBS (vehicle), sucrose, and OS were administered by stomach gavage. Body weight, food intake, and markers of liver function (activities of aspartate aminotransferase and alanine aminotransferase) were not affected by the treatments. HOS treatment decreased levels of serum glucose, insulin, and homeostasis model assessment-insulin resistance compared with sucrose treatment. However, serum adiponectin levels of the HOS group were higher than those of the sucrose groups. Serum levels of the pro-inflammatory cytokines interleukin-6 (IL-6) and fetuin-A were lower in the HOS group than in the sucrose groups. Hepatic gene expression levels of pro-inflammatory cytokines and related factors (fetuin-A, NF-κB, TLR4, TNF-alpha, and IL-6) were decreased and the levels of insulin signaling-related molecules (sirtuin 1, insulin receptor, and Akt) were increased in HOS-treated mice as compared with sucrose-treated mice. These results demonstrate that OS treatment is effective in improving glucose control and inflammation in high fat diet-fed mice.

Anti-inflammatory effect of 635 nm irradiations on in vitro direct/indirect irradiation model.

Low-level laser therapy (LLLT) has been promoted for its beneficial effects on tissue healing and pain relief. As during laser treatment it is possible to irradiate only a small area of the surface body or wound and, correspondingly, of a very small volume of the circulating blood, it is necessary to explain how its photomodification can lead to a wide spectrum of therapeutic effects. To establish the experimental model for indirect irradiation, irradiation with 635 nm was performed on immortalized human gingival fibroblasts (IGFs) in the presence of Porphyromonas gingivalis lipopolysaccharides (LPS). The irradiated medium was transferred to non-irradiated IGFs which were compared with direct irradiated IGFs. The protein expressions were assessed by Western blot, and prostaglandin E2 (PGE2 ) was measured using an enzyme-linked immunoassay. Reactive oxygen species (ROS) were measured by DCF-DA; cytokine profiles were assessed using a human inflammation antibody array. Cyclooxygenase-2 (COX-2) protein expression and PGE2 production were significantly increased in the LPS-treated group and decreased in both direct and indirect irradiated IGFs. Unlike direct irradiated IGFs, ROS level in indirect irradiated IGFs was decreased by time-dependent manners. There were significant differences of released granulocyte colony-stimulating factor (G-CSF), regulated on activated normal T-cell expressed and secreted (RANTES), and I-TAC level observed compared with direct and indirect irradiated IGFs. In addition, in the indirect irradiation group, phosphorylations of C-Raf and Erk1/2 increased significantly compared with the direct irradiation group. Thus, we suggest that not only direct exposure with 635 nm light, but also indirect exposure with 635 nm light can inhibit activation of pro-inflammatory mediators and may be clinically useful as an anti-inflammatory tool.

Production of a low calorie mandarin juice by enzymatic conversion of constituent sugars to oligosaccharides and prevention of insoluble glucan formation.

Over 99% of sucrose in mandarin juice (57.1 g/l in original juice to 428.4 g/l in concentrated juice) was enzymatically converted to glucooligosaccharides using 3 U dextransucrase/ml prepared from Leuconostoc mesenteroides at 28 °C. The oligosaccharide synthesis yields were 51 and 47% for the original and the concentrated mandarin juice, respectively. The degree of polymerization of oligosaccharides in the enzyme-modified juice was 2-7. Calories in the original and modified mandarin juice were 433 and 301 kcal/l (30.5% reduction). Compared with the original juice, the enzyme-modified juice showed 82% decrease of insoluble glucan formation by mutansucrase from Streptococcus mutans. A sensory evaluation of the juices revealed that the original and modified mandarin juices had sweetness values of 4.5 and 4.9 and the same values for overall acceptability.

Lime application for the efficient production of nutraceutical glucooligosaccharides from Leuconostoc mesenteroides NRRL B-742 (ATCC13146).

We have previously demonstrated the production of glucooligosaccharides via a fermentation of sucrose with Leuconostoc mesenteroides NRRL B-742 using sodium hydroxide (NaOH) to control the pH. Because NaOH is expensive, we sought to minimize the cost of our process by substituting hydrated lime and saccharate of lime (lime sucrate) in its place. The yield of glucooligosaccharides using either 5 % lime (41.4 ± 0.5 g/100 g) or 5 % lime sucrate (40.0 ± 1.4 g/100 g) were both similar to the NaOH control (42.4 ± 1.5 g/100 g). Based on this, it appears that the cost associated with pH control in our process can be reduced by a factor of approximately 2.4 using lime instead of NaOH. Because our chromatographic stage is based on a Ca(2+)-form resin to separate glucooligosaccharides, the use of lime not only negates the need for costly de-salting via ion-exchange (elimination of two ion-exchange sections) prior to separation, but also greatly reduces the resin regeneration cost.

Inhibition effect of flavonoid compounds against neuraminidase expressed in Pichia pastoris.

Neuraminidase (NA) is one of the two glycoproteins on the surface of influenza virus, which cleaves terminal sialic acid residues and facilitates the release of virions from infected cells. The recombinant NA from H5N1 influenza virus strain A/Vietnam/1203/04 was expressed in Pichia pastoris X33 as a 45 kDa protein that displayed a K m of 9.96 ± 1.26 µM with fluorogenic substrate, 2'-(4-methylumbelliferyl)-α-D-N-acetyl neuraminic acid. Partially purified NA was used for the inhibition and kinetic assays with eight flavonoid compounds and gallic acid. Among them, gallocatechin gallate (GCG) showed the best inhibition against NA with the IC50 of 8.98 ± 0.46 µM and showed a competitive inhibition pattern with K i value of 8.34 ± 0.25 µM. In molecular docking experiments, GCG displayed a binding energy of -13.71 kcal/mol to the active site of NA and the galloyl moiety was required for NA inhibition activity.

Improvement of branched-chain amino acid production by isolated high-producing protease from Bacillus amyloliquefaciens NY130 on isolated soy/whey proteins and their muscle cell protection.

Branched-chain amino acids (BCAAs) are vital components of human and animal nutrition that contribute to the building blocks of proteins. In this study, 170 protease-producing strains were isolated and screened from soy-fermented foods. Bacillus amyloliquefaciens NY130 was obtained from Cheonggukjang with high production of BCAAs. Optimal production of protease from B. amyloliquefaciens NY130 (protease NY130) was achieved at 42 °C and pH 6.0 for 21 h. It was purified and determined as 27- and 40 kDa. Protease NY130 showed maximum activity at pH 9.0 and 45 °C with Km value of 10.95 mg for ISP and 1.69 mg for WPI. Protease-treated ISP and WPI showed increased sweetness and saltiness via electronic tongue analysis and enhanced the protective effect against oxidative stress in C2C12 myocytes by increasing p-mTOR/mTOR protein expression to 160%. This work possesses potential in producing BCAAs by using protease for utilization in food.

Exploring Chitosan Lactate as a Multifunctional Additive: Enhancing Quality and Extending Shelf Life of Whole Wheat Bread.

The shelf life of whole wheat bread (WWB) significantly impacts its freshness and overall quality. This research investigated the impact of chitosan lactate (CL) on various characteristics influencing the shelf life of WWB, including its physical, chemical, textural, antimicrobial, and sensory attributes. These characteristics were evaluated by conducting various experiments such as physical inspection, moisture, impedance, swelling, color, texture, FTIR, microbiological, and sensory analysis. CL with different concentrations was incorporated into WWB formulations: P0.0 (0.0% w/w CL, control), P0.5 (0.5% w/w CL), P1.0 (1.0% w/w CL), P2.0 (2.0% w/w CL), and P3.0 (3.0% w/w CL). The inclusion of CL promoted the Maillard reaction (MR) compared to P0.0. The promotion of MR resulted in the formation of a shinier crust, which increased as the CL content was increased. P0.5 comprised large-sized pores and exhibited increased loaf height. CL-containing WWB formulations showed an increased moisture content and decreased impedance values compared to the control. FTIR analysis of P0.5 demonstrated the enhanced interaction and bonding of water molecules. P0.5 demonstrated optimal textural, colorimetric, and antimicrobial properties compared to other formulations. The sensory attributes of WWBs remain unchanged despite CL addition. In conclusion, P0.5 exhibited optimal characteristics associated with better quality and prolonged shelf life.