Anti-biofilm effect of enzymatic hydrolysates of ovomucin in Listeria monocytogenes and Staphylococcus aureus.

Despite modern advances in food hygiene, food poisoning due to microbial contamination remains a global problem, and poses a great threat to human health. Especially, Listeria monocytogenes and Staphylococcus aureus are gram-positive bacteria found on food-contact surfaces with biofilms. These foodborne pathogens cause a considerable number of food poisoning and infections annually. Ovomucin (OM) is a water-insoluble gel-type glycoprotein in egg whites. Enzymatic hydrolysis can be used to improve the bioactive properties of OM. This study aimed to investigate whether ovomucin hydrolysates (OMHs) produced using five commercial enzymes (Alcalase®, Bromelain, α-Chymotrypsin, Papain, and Pancreatin) can inhibit the biofilm formation of L. monocytogenes ATCC 15313, L. monocytogenes H7962, S. aureus KCCM 11593, and S. aureus 7. Particularly, OMH prepared with papain (OMPP; 500 µg/mL) significantly inhibited biofilm formation in L. monocytogenes ATCC 15313, L. monocytogenes H7962, S. aureus KCCM 11593, and S. aureus 7 by 85.56 %, 80.28 %, 91.70 %, and 79.00 %, respectively. In addition, OMPP reduced the metabolic activity, exopolysaccharide production (EPS), adhesion ability, and gene expression associated with the biofilm formation of these bacterial strains. These results suggest that OMH, especially OMPP, exerts anti-biofilm effects against L. monocytogenes and S. aureus. Therefore, OMPP can be used as a natural anti-biofilm agent to control food poisoning in the food industry.

Posttranscriptional modulation of KCNQ2 gene expression by the miR-106b microRNA family.

MicroRNAs (miRNAs) have recently emerged as important regulators of ion channel expression. We show here that select miR-106b family members repress the expression of the KCNQ2 K+ channel protein by binding to the 3'-untranslated region of KCNQ2 messenger RNA. During the first few weeks after birth, the expression of miR-106b family members rapidly decreases, whereas KCNQ2 protein level inversely increases. Overexpression of miR-106b mimics resulted in a reduction in KCNQ2 protein levels. Conversely, KCNQ2 levels were up-regulated in neurons transfected with antisense miRNA inhibitors. By constructing more specific and stable forms of miR-106b controlling systems, we further confirmed that overexpression of precursor-miR-106b-5p led to a decrease in KCNQ current density and an increase in firing frequency of hippocampal neurons, while tough decoy miR-106b-5p dramatically increased current density and decreased neuronal excitability. These results unmask a regulatory mechanism of KCNQ2 channel expression in early postnatal development and hint at a role for miR-106b up-regulation in the pathophysiology of epilepsy.

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.

Neuroprotective effects of hydroponic ginseng fermented by Lactococcus lactis KC24 in oxidatively stressed SH-SY5Y cells.

BACKGROUND: Panax ginseng Meyer, a traditional herb in Asia, contains bioactive compounds such as polyphenolic compounds, flavonoids, and ginsenosides. Furthermore, fermentation with probiotics can promote the biofunctional activities of ginseng. This study's object was to investigate the neuroprotective effect of hydroponic ginseng against hydrogen peroxide (H2 O2 )-induced cytotoxicity and its effect on the fermentation time. RESULTS: Nonfermented hydroponic ginseng (HNF) was fermented with Lactococcus lactis KC24 at 37 °C for 12 h (H12F) or 24 h (H24F). As fermentation progressed, the content of ginsenosides Rd and F2 increased slightly. The viability of cells pretreated with H2 O2 -exposed nonfermented soil-cultivated ginseng (SNF), HNF, H12F, and H24F gradually improved. In addition, a similar cytotoxicity trend was observed for the level of lactate dehydrogenase released. Fermentation with L. lactis KC24 also enhanced the protective effect of HNF in all assays related to the neuroprotective pathway. In other words, superoxide dismutase and catalase messenger RNA (mRNA) expression levels were upregulated in H24F-treated cells. Similarly, H24F also upregulated the mRNA and protein expression of brain-derived neurotrophic factor to the highest observed concentration. Moreover, the Bax/Bcl-2 ratio was the lowest after H24F pretreatment in H2 O2 -induced SH-SY5Y cells. Attenuating the cytotoxicity in H2 O2 -induced SH-SY5Y cells, H24F markedly reduced caspase-3 and -9 mRNA expression and caspase-3 activity. CONCLUSION: These results suggest that HNF exhibited higher neuroprotection than SNF, which was enhanced after fermentation. This study demonstrates that H12F and H24F can be potential ingredients for developing healthy functional foods and pharmaceutical materials. © 2023 Society of Chemical Industry.

Probiotic Lactobacillus fermentum KU200060 isolated from watery kimchi and its application in probiotic yogurt for oral health.

Lactobacillus fermentum KU200060 was isolated from watery kimchi and its probiotic characteristics were evaluated, including tolerance to artificial gastric acid and bile salt, production of enzymes, ability to adhere to HT-29 cells, and antibiotic susceptibility. The antibacterial and antibiofilm effects of L. fermentum KU200060 against Streptococcus mutans KCTC 5316 were compared to those of Lactobacillus rhamnosus GG and Lactobacillus brevis KU15006. L. fermentum KU200060 demonstrated higher antibacterial activity and inhibition of biofilm formation by S. mutans than L. rhamnosus GG via inhibiting formation of water-insoluble glucan and related gene expression. In addition, L. fermentum KU200060 was applied as a probiotic in yogurt, and its physicochemical property and sensory value demonstrated its potential as a yogurt starter. The physicochemical characteristics and consumer acceptability of the probiotic yogurt containing L. fermentum KU200060 were not significantly different compared to those of the control yogurt. Therefore, L. fermentum KU200060 could be used for oral health in the probiotic industry.

Improved in vitro antioxidant properties and hepatoprotective effects of a fermented Inula britannica extract on ethanol-damaged HepG2 cells.

This study aimed to improve antioxidant effect and hepatoprotective effect of Inula britannica using fermentation. Epigallocatechin gallate (EGCG) in an I. britannica extract was found to be upregulated from 2.06 to 10.28 µg/mg during fermentation (p < 0.001). After fermentation, DPPH radical-scavenging ABTS radical-scavenging, and superoxide anion-scavenging abilities increased to 92.65%, 694.25 µM Trolox/mL, and 86.38%, respectively, at 500 µg/mL (p < 0.05). Cupric-ion-reducing capacity with formation of the Cu+-neocuproine complex increased by 5.88%, 6.38%, 3.24%, and 8.55% at 62.5 to 500 µg/mL. Ferric-ion-reducing capacity of the fermented extract increased by 20%, 7.16%, 3.85%, and 5.45% at each concentration (p < 0.05). Unfermented extracts yielded cell viability of 91.42%, 90.59%, 88.38%, and 79.17%, whereas the fermented extract yielded 100.28%, 99.66%, 96.15%, and 89.90%, respectively, at each concentration in ethanol-damaged HepG2 cells (p < 0.05). Additionally, the fermented extract decreased alanine transaminase activity from 117.2 to 61.7 U/mL in the ethanol-damaged HepG2 cell line (p < 0.01). Overall, both antioxidant and hepatoprotective effect increased by fermentation in I. britannica extract. These properties are expected to lead to new antioxidant agents via production of EGCG by fermentation.

Ethanol Elevates Excitability of Superior Cervical Ganglion Neurons by Inhibiting Kv7 Channels in a Cell Type-Specific and PI(4,5)P2-Dependent Manner.

Alcohol causes diverse acute and chronic symptoms that often lead to critical health problems. Exposure to ethanol alters the activities of sympathetic neurons that control the muscles, eyes, and blood vessels in the brain. Although recent studies have revealed the cellular targets of ethanol, such as ion channels, the molecular mechanism by which alcohol modulates the excitability of sympathetic neurons has not been determined. Here, we demonstrated that ethanol increased the discharge of membrane potentials in sympathetic neurons by inhibiting the M-type or Kv7 channel consisting of the Kv7.2/7.3 subunits, which were involved in determining the membrane potential and excitability of neurons. Three types of sympathetic neurons, classified by their threshold of activation and firing patterns, displayed distinct sensitivities to ethanol, which were negatively correlated with the size of the Kv7 current that differs depending on the type of neuron. Using a heterologous expression system, we further revealed that the inhibitory effects of ethanol on Kv7.2/7.3 currents were facilitated or diminished by adjusting the amount of plasma membrane phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2). These results suggested that ethanol and PI(4,5)P2 modulated gating of the Kv7 channel in superior cervical ganglion neurons in an antagonistic manner, leading to regulation of the membrane potential and neuronal excitability, as well as the physiological functions mediated by sympathetic neurons.

Improved Antioxidant, Anti-inflammatory, and Anti-adipogenic Properties of Hydroponic Ginseng Fermented by Leuconostoc mesenteroides KCCM 12010P.

Hydroponic ginseng (HPG) has been known to have various bio-functionalities, including an antioxidant effect. Recently, fermentation by lactic acid bacteria has been studied to enhance bio-functional activities in plants by biologically converting their chemical compounds. HPG roots and shoots were fermented with Leuconostoc mesenteroides KCCM 12010P isolated from kimchi. The total phenolic compounds, antioxidant, anti-inflammatory, and anti-adipogenic effects of these fermented samples were evaluated in comparison with non-fermented samples (control). During 24 h fermentation of HPG roots and shoots, the viable number of cells increased to 7.50 Log colony forming unit (CFU)/mL. Total phenolic and flavonoid contents of the fermented HPG roots increased by 107.19% and 645.59%, respectively, compared to non-fermented HPG roots. The antioxidant activity of fermented HPG, as assessed by 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), ß-carotene-linoleic, and ferric reducing antioxidant power (FRAP) assay, was also significantly enhanced. In an anti-inflammatory effect of lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, the nitric oxide content and the expression of inducible nitric oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) decreased when treated with fermented samples. Simultaneously, lipid accumulation in 3T3-L1 adipocyte was reduced when treated with fermented HPG. Fermentation by L. mesenteroides showed improved antioxidant, anti-inflammatory and anti-adipogenic HPG effects. These results show that fermented HPG has potential for applications in the functional food industry.

Antioxidant and antigenotoxic effect of dairy products supplemented with red ginseng extract.

The purpose of this study was to evaluate the antioxidant and antigenotoxic effect of dairy products milk (M) and yogurt (Y) after the addition of 2% red ginseng extract to milk (RM) and to yogurt (RY). Total phenolic content, total flavonoid content, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, oxygen radical absorbance capacity, and total radical trapping antioxidant potential were determined in the samples. Furthermore, antigenotoxic effect of samples was measured, using comet assay in human leukocytes. Total phenolic content and total flavonoid content of RM [38.3 ± 0.8 mg of gallic acid equivalents (GAE)/100 g, 23.6 ± 0.1 mg of quercetin equivalents (QE)/100 g] and RY (41.1 ± 0.9 mg of GAE/100 g, 18.7 ± 0.1 mg of QE/100 g), respectively, were higher than those of M (6.31 ± 0.2 mg of GAE/100 g, 10.4 ± 0.1 mg of QE/100 g) and Y (8.1 ± 0.9 mg of GAE/100 g, 8.4 ± 0.2 mg of QE/100 g), respectively. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and oxygen radical absorbance capacity values increased significantly after the addition of 2% red ginseng in both. Additionally, the total radical trapping antioxidant potential in RM (787.7 ± 7.0 µg/mL) was lower than in M (2074.0 ± 28.4 µg/mL). The H2O2-induced DNA damage in RY (0.1 ± 0.0 mg/mL) was less than the damage in Y (0.4 ± 0.0 mg/mL), but we found no significant difference between M and RM. This study indicates that supplementation with red ginseng can fortify the antioxidant and antigenotoxic effects of dairy products effectively.

A Mercaptoacetamide-Based Class II Histone Deacetylase Inhibitor Suppresses Cell Migration and Invasion in Monomorphic Malignant Human Glioma Cells by Inhibiting FAK/STAT3 Signaling.

Histone deacetylase inhibitors (HDACIs) have emerged as potential anticancer agents for the treatment of solid and hematopoietic cancers. Several HDACIs delay cell growth, induce differentiation, or activate apoptosis in multiple types of tumors, including glioblastomas. In the present study, we showed that the mercaptoacetamide-based HDACI W2 inhibits cell migration and invasion in monomorphic malignant human glioma cells. W2 treatment significantly decreased the activity and expression levels of matrix metalloprotease-2 in malignant A172 cells but not in U373MG cells. Key signaling pathways involved in cell migration and invasion, including PI3K-AKT, ERK-JNK-P38, and FAK/STAT3, were examined to identify the mechanism of action of W2. W2 increased the phosphorylation of AKT and altered cell migration and invasion in an AKT-independent manner. W2 inhibited the phosphorylation of FAK/STAT3, and treatment with a FAK/STAT3 inhibitor significantly suppressed cancer cell migration and MMP-2 activity in the presence of W2. In addition, W2 significantly inhibited the nuclear translocation of phospho-STAT3. Taken together, our results suggest that W2 suppresses cancer cell migration and invasion by inhibiting FAK/STAT3 signaling and STAT3 translocation to the nucleus in monomorphic malignant human glioma cells. J. Cell. Biochem. 118: 4672-4685, 2017. © 2017 Wiley Periodicals, Inc.

Antioxidative and Anticanceric Activities of Magnolia (Magnolia denudata) Flower Petal Extract Fermented by Pediococcus acidilactici KCCM 11614.

In this study, the effects of magnolia (Magnolia (M.) denudata) extract fermentation in increasing the extract's antioxidative and anticancer activities were investigated. Magnolia was fermented by Pediococcus acidilactici KCCM 11614. The total phenolic content was determined by the Folin-Ciocalteu's method and the antioxidative effects by 1,1-diphenyl-2-picrylhydrazy (DPPH) and ferric reducing ability of plasma (FRAP) assay. Anticancer activity against cancer and normal cells was determined using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT). Total phenolic content during fermentation increased from 38.1 to 47.0 mg gallic acid equivalent (GAE)/g of solid matter. The radical scavenging activity was 91.4% after 72 h fermentation. Fermented magnolia's antioxidative effect was threefold higher than that of the (non-fermented) control. Fermentation (48 h) increased anticanceric activity against AGS, LoVo, and MCF-7 cancer cells 1.29- to 1.36-fold compared with that of the control, but did not affect MRC-5 (normal) cells, suggesting that fermented magnolia could be used as a natural antioxidative and anticancer agent.

Antimicrobial activity of acid-hydrolyzed Citrus unshiu peel extract in milk.

Citrus fruit (Citrus unshiu) peels were extracted with hot water and then acid-hydrolyzed using hydrochloric acid. Antimicrobial activities of acid-hydrolyzed Citrus unshiu peel extract were evaluated against pathogenic bacteria, including Bacillus cereus, Staphylococcus aureus, and Listeria monocytogenes. Antilisterial effect was also determined by adding extracts at 1, 2, and 4% to whole, low-fat, and skim milk. The cell numbers of B. cereus, Staph. aureus, and L. monocytogenes cultures treated with acid-hydrolyzed extract for 12h at 35°C were reduced from about 8log cfu/mL to <1log cfu/mL. Bacillus cereus was more sensitive to acid-hydrolyzed Citrus unshiu peel extract than were the other bacteria. The addition of 4% acid-hydrolyzed Citrus unshiu extracts to all types of milk inhibited the growth of L. monocytogenes within 1d of storage at 4°C. The results indicated that Citrus unshiu peel extracts, after acid hydrolysis, effectively inhibited the growth of pathogenic bacteria. These findings indicate that acid hydrolysis of Citrus unshiu peel facilitates its use as a natural antimicrobial agent for food products.

Anti-inflammatory, antioxidant effects, and antimicrobial effect of Bacillus subtilis P223.

This study aimed to investigate the anti-inflammatory, antioxidant, and antimicrobial effects of Bacillus subtilis P223 which is known to have probiotic properties. B. subtilis P223 that had been killed by heat in LPS-induced RAW 264.7 cells decreased nitric oxide (NO) production. Furthermore, it inhibited the expression of proinflammatory cytokines such interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha (TNF-α). Heat-killed B. subtilis P223 also inhibited the expression of the nuclear factor (NF)-κB cellular signaling pathway, and it showed reactive oxygen species (ROS) reduction. In DPPH, ABTS, and SOD assay, B. subtilis P223 showed a high antioxidant capacity, and inhibited the growth of skin related pathogens including Staphylococcus aureus and Propionibacterium acnes. This study therefore demonstrated the various functional properties of B. subtilis P223 as probiotics, and suggested the potential for its application as functional material.

Immunostimulatory Effect of Ovomucin Hydrolysates by Pancreatin in RAW 264.7 Macrophages via Mitogen-Activated Protein Kinase (MAPK) Signaling Pathway.

Ovomucin (OM), which has insoluble fractions is a viscous glycoprotein, found in egg albumin. Enzymatic hydrolysates of OM have water solubility and bioactive properties. This study investigated that the immunostimulatory effects of OM hydrolysates (OMHs) obtained by using various proteolytic enzymes (Alcalase®, bromelain, α-chymotrypsin, Neutrase®, pancreatin, papain, Protamax®, and trypsin) in RAW 264.7 cells. The results showed that OMH prepared with pancreatin (OMPA) produced the highest levels of nitrite oxide in RAW 264.7 cells, through upregulation of inducible nitric oxide synthase mRNA expression. The production of pro-inflammatory cytokines such as tumor necrosis factor-α and interleukin-6 were increased with the cytokines mRNA expression. The effect of OMPA on mitogen-activated protein kinase signaling pathway was increased the phosphorylation of p38, c-Jun NH2-terminal kinase, and extracellular signal-regulated kinase in a concentration-dependent manner. Therefore, OMPA could be used as a potential immune-stimulating agent in the functional food industry.

Heat-Treated Paraprobiotic Latilactobacillus sakei KU15041 and Latilactobacillus curvatus KU15003 Show an Antioxidant and Immunostimulatory Effect.

The lactic acid bacteria, including Latilactobacillus sakei and Latilactobacillus curvatus, have been widely studied for their preventive and therapeutic effects. In this study, the underlying mechanism of action for the antioxidant and immunostimulatory effects of two strains of heat-treated paraprobiotics was examined. Heat-treated L. sakei KU15041 and L. curvatus KU15003 showed higher radical scavenging activity in both the 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assays than the commercial probiotic strain LGG. In addition, treatment with these two strains exhibited immunostimulatory effects in RAW 264.7 macrophages, with L. curvatus KU15003 showing a slightly higher effect. Additionally, they promoted phagocytosis and NO production in RAW 264.7 cells without any cytotoxicity. Moreover, the expression of tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6 was upregulated. These strains resulted in an increased expression of inducible nitric oxide synthase and cyclooxygenase-2. Moreover, the nuclear factor-κB and mitogen-activated protein kinase signaling pathways were stimulated by these strains. These findings suggest the potential of using L. sakei KU15041 and L. curvatus KU15003 in food or by themselves as probiotics with antioxidant and immune-enhancing properties.

Immune-Enhancing Effect of Heat-Treated Levilactobacillus brevis KU15159 in RAW 264.7 Cells.

Probiotics are alive microbes that present beneficial to the human's health. They influence immune responses through stimulating antibody production, activating T cells, and altering cytokine expression. The probiotic characteristics of Levilactobacillus brevis KU15159 were evaluated on the tolerance and adherence to gastrointestinal conditions. L. brevis KU15159 was safe in a view of producing various useful enzymes and antibiotic sensitivity. Heat-treated L. brevis KU15159 increased production of nitric oxide (NO) and phagocytic activity in RAW 264.7 cells. In addition, heat-treated L. brevis KU15159 upregulated the expression of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6, at protein as well as mRNA levels. In addition, the mitogen-activated protein kinase (MAPK) pathway, which regulates the immune system, was activated by heat-treated L. brevis KU15159. Therefore, L. brevis KU15159 exhibited an immune-enhancing effect by the MAPK pathway in macrophage.

Fermentative effects by probiotic Lactobacillus brevis B7 on antioxidant and anti-inflammatory properties of hydroponic ginseng.

Soil-cultivation presents environmental limitations and requires considerable labor, space, and water supply. Alternatively, hydroponically-cultured ginseng (HG) was improved its productivity, availability, and functionality. Improvement of bio-functionality by probiotic fermentation also has been studied. Therefore, in this study, HG was fermented using probiotics to enhance antioxidant and anti-inflammatory activities. Soil-cultivated ginseng (SG), 1 and 2-year HG (HG1, HG2) were extracted using 70% ethanol and fermented by Lactobacillus brevis B7. After fermentation, the phenolic and flavonoid contents, and antioxidant and NO scavenging activities were increased, and HG showed higher bioactivities than SG. Particularly, fermented HG2 showed the highest antioxidant and anti-inflammatory activities and significantly decreased the level of inflammatory mediators. Furthermore, fermented HG2 also effectively inhibited NF-κB signaling pathway. These results suggested that fermented HG significantly enhanced functionality compared to SG and non-fermented HG. This suggests that fermented HG is a potentially useful ingredient for developing health-functional foods or pharmaceutical materials.

Purification and characterization of a ginsenoside Rb(1)-hydrolyzing ß-glucosidase from Aspergillus niger KCCM 11239.

Rb(1)-hydrolyzing ß-glucosidase from Aspergillus niger KCCM 11239 was studied to develop a bioconversion process for minor ginsenosides. The specific activity of the purified enzyme was 46.5 times greater than that of the crude enzyme. The molecular weight of the native enzyme was estimated to be approximately 123 kDa. The optimal pH of the purified enzyme was pH 4.0, and the enzyme proved highly stable over a pH range of 5.0-10.0. The optimal temperature was 70 °C, and the enzyme became unstable at temperatures above 60 °C. The enzyme was inhibited by Cu(2+), Mg(2+), Co(2+), and acetic acid (10 mM). In the specificity tests, the enzyme was found to be active against ginsenoside Rb(1), but showed very low levels of activity against Rb(2), Rc, Rd, Re, and Rg(1). The enzyme hydrolyzed the 20-C,ß-(1→6)-glucoside of ginsenoside Rb(1) to generate ginsenoside Rd and Rg(3), and hydrolyzed 3-C,ß-(1→2)-glucoside to generate F(2). The properties of the enzyme indicate that it could be a useful tool in biotransformation applications in the ginseng industry, as well as in the development of novel drug compounds.

Improved Antioxidative, Anti-Inflammatory, and Antimelanogenic Effects of Fermented Hydroponic Ginseng with Bacillus Strains.

Compared with traditionally cultured ginseng, hydroponic ginseng (HG) contains more remarkable bioactive compounds, which are known to exert diverse functional effects. This study aimed to enhance the multifunctional effects, including the antioxidative, anti-inflammatory, and antimelanogenic effects, exhibited by fermented HG with Bacillus strains, such as Bacillus subtilis KU43, Bacillus subtilis KU201, Bacillus polyfermenticus SCD, and Bacillus polyfermenticus KU3, at 37 °C for 48 h. After fermentation by B. subtilis KU201, the antioxidant activity, determined using ABTS and FRAP assays, increased from 25.30% to 51.34% and from 132.10% to 236.27%, respectively, accompanied by the enhancement of the phenolic compounds and flavonoids. The inflammation induced in RAW 264.7 cells by lipopolysaccharide (LPS) was ameliorated with fermented HG, which regulated the nitric oxide (NO), prostaglandin E2 (PGE2), and proinflammatory markers (tumor necrosis factor (TNF)-α, and interleukin (IL)-1ß and IL-6). The treatment with fermented HG inhibited the melanin accumulation in B16F10 cells induced by α-melanocyte-stimulating hormone (α-MSH) by controlling the concentrations of melanin synthesis and tyrosinase activity. These results indicate that the HG exhibited stronger antioxidative, anti-inflammatory, and antimelanogenic effects after fermentation. Consequently, HG fermented by Bacillus strains can potentially be used as an ingredient in cosmetological and pharmaceutical applications.

Role of excitatory amino acid transporter-2 (EAAT2) and glutamate in neurodegeneration: opportunities for developing novel therapeutics.

Glutamate is an essential excitatory neurotransmitter regulating brain functions. Excitatory amino acid transporter (EAAT)-2 is one of the major glutamate transporters expressed predominantly in astroglial cells and is responsible for 90% of total glutamate uptake. Glutamate transporters tightly regulate glutamate concentration in the synaptic cleft. Dysfunction of EAAT2 and accumulation of excessive extracellular glutamate has been implicated in the development of several neurodegenerative diseases including Alzheimer's disease, Huntington's disease, and amyotrophic lateral sclerosis. Analysis of the 2.5 kb human EAAT2 promoter showed that NF-κB is an important regulator of EAAT2 expression in astrocytes. Screening of approximately 1,040 FDA-approved compounds and nutritionals led to the discovery that many ß-lactam antibiotics are transcriptional activators of EAAT2 resulting in increased EAAT2 protein levels. Treatment of animals with ceftriaxone (CEF), a ß-lactam antibiotic, led to an increase of EAAT2 expression and glutamate transport activity in the brain. CEF has neuroprotective effects in both in vitro and in vivo models based on its ability to inhibit neuronal cell death by preventing glutamate excitotoxicity. CEF increases EAAT2 transcription in primary human fetal astrocytes through the NF-κB signaling pathway. The NF-κB binding site at -272 position was critical in CEF-mediated EAAT2 protein induction. These studies emphasize the importance of transcriptional regulation in controlling glutamate levels in the brain. They also emphasize the potential utility of the EAAT2 promoter for developing both low and high throughput screening assays to identify novel small molecule regulators of glutamate transport with potential to ameliorate pathological changes occurring during and causing neurodegeneration.