Fermented mixed grain ameliorates chronic stress-induced depression-like behavior and memory deficit.

Fermented mixed grain (FG) has beneficial anti-cancer, antioxidant, and anti-inflammatory effects. In this study, we investigated the effects of FG on gut inflammation, brain dysfunction, and anxiety/depression-like behavior induced by unpredictable chronic mild stress (UCMS) in mice. Mice were administered mixed grain or FG for 3 weeks and were then exposed to UCMS for 4 weeks. FG administration ameliorated stress-induced anxiety/despair-like behavior. FG administration also prevented UCMS-induced memory impairment. Additionally, the mRNA levels of 5-HTR1A and IL-6 were restored to normal levels in the brains of FG-administered mice. FG administration also inhibited intestinal damage in stressed mice compared with that in the UCMS (without FG) group. These results suggest that FG can alleviate stress-induced intestinal damage, brain dysfunction, and cognitive impairment.

Preventive effect of fermented whey protein mediated by Lactobacillus gasseri IM13 via the PI3K/AKT/FOXO pathway in muscle atrophy.

This study investigated the preventive effects of whey protein fermented with Lactobacillus gasseri IM13 (F-WP) against dexamethasone (DEX)-induced muscle atrophy. C2C12 muscle cells were treated with F-WP followed by DEX treatment. DEX treatment inhibited myotube formation and the expression of myogenic regulatory factors; however, pretreatment with F-WP attenuated DEX-induced damage. F-WP significantly activated the phosphorylation of the IGF-1/PI3K/AKT pathway and improved muscle homeostasis suppressed by DEX. Moreover, F-WP alleviated the phosphorylation of mTOR, S6K1, and 4E-BP1 and enhanced muscle protein synthesis. Muscle-specific ubiquitin ligases and autophagy lysosomes, which were activated by the dephosphorylation of FOXO3a by DEX treatment, were significantly attenuated by F-WP pretreatment of myotubes. For peptidomic analysis, F-WP was fractionated using preparative HPLC (prep-HPLC), and the amino acid sequences of 11 peptides were identified using MALDI-TOF/MS/MS. In conclusion, fermentation of whey protein by the specific probiotic strain IM13 produced bioactive peptides with high antioxidant and anti-sarcopenic effects, which markedly enhanced myogenesis and muscle protein synthesis while diminishing muscle protein degradation compared with intact whey protein.

Preventive effect of peptides derived from fermented milk on chronic stress-induced brain damage and intestinal dysfunction in mice.

This study investigated the preventive effects of peptides derived from milk fermented with the probiotic strain Lactobacillus gasseri 505 (505) against stress-related brain damage and anxiety-like behavior. The peptides MKPWIQPKTKVIPYVRYL (Pep14) and VYQHQKAMKPWIQPKTKVIPYVRYL (Pep21), which exhibit high antioxidant and anti-inflammatory activities, were administered to stressed mice. The results showed that the stress mechanism in the gut-brain axis was regulated by pretreatment with both peptides, leading to inhibition of neurodevelopment and neuroinflammation through the hypothalamic-pituitary-adrenal (HPA) axis, based on the expression of related mRNA and proteins. The expression of colonic inflammation-related mRNA and proteins was also reduced. Moreover, anxiety-like behavior was significantly reduced in mice treated with Pep14 and Pep21. These results indicate that the bioactive peptides Pep14 and Pep21, derived from milk fermented with 505, may prevent stress-induced brain damage and anxiety-like behavior via regulation of the HPA axis.

Enhanced Cholesterol-Lowering and Antioxidant Activities of Soymilk by Fermentation with Lactiplantibacillus plantarum KML06.

This study aimed to evaluate the cholesterol-lowering and antioxidant activities of soymilk fermented with probiotic Lactobacillaceae strains and to investigate the production of related bioactive compounds. Lactiplantibacillus plantarum KML06 (KML06) was selected for the fermentation of soymilk because it has the highest antioxidant, cholesterol-lowering, and ß-glucosidase activities among the 10 Lactobacillaceae strains isolated from kimchi. The genomic information of strain KML06 was analyzed. Moreover, soymilk fermented with KML06 was evaluated for growth kinetics, metabolism, and functional characteristics during the fermentation period. The number of viable cells, which was similar to the results of radical scavenging activities and cholesterol assimilation, as well as the amount of soy isoflavone aglycones, daidzein, and genistein, was the highest at 12 h of fermentation. These results indicate that soymilk fermented with KML06 can prevent oxidative stress and cholesterol-related problems through the production of soy isoflavone aglycones.

Erratum to: Rheological, Physicochemical, Microbiological, and Aroma Characteristics of Sour Creams Supplemented with Milk Protein Concentrate.

[This corrects the article DOI: 10.5851/kosfa.2023.e16.].

Rheological, Physicochemical, Microbiological, and Aroma Characteristics of Sour Creams Supplemented with Milk Protein Concentrate.

Milk protein concentrate (MPC) is widely used to enhance the stability and texture of fermented dairy products. However, most research has focused on yogurt products, and the effects of MPC on sour cream characteristics remain unknown. Therefore, we investigated the effects of different MPC levels (0%, 1%, 2%, and 3% w/w) on the rheological, physicochemical, microbiological, and aroma characteristics of sour creams in this study. We found that MPC supplementation stimulated the growth of lactic acid bacteria (LAB) in sour creams, resulting in higher acidity than that in the control sample due to the lactic acid produced by LAB. Three aroma compounds, acetaldehyde, diacetyl, and acetoin, were detected in all sour cream samples. All sour creams showed shear-thinning behavior (n=0.41-0.50), and the addition of MPC led to an increase in the rheological parameters (ηa,50, K, G', and G″). In particular, sour cream with 3% MPC showed the best elastic property owing to the interaction between denatured whey protein and caseins. In addition, these protein interactions resulted in the formation of a gel network, which enhanced the water-holding capacity and improved the whey separation. These findings revealed that MPC can be used as a supplementary protein to improve the rheological and physicochemical characteristics of sour cream.

A Synbiotic Combination of Lactobacillus gasseri 505 and Cudrania tricuspidata Leaf Extract Prevents Stress-Induced Testicular Dysfunction in Mice.

This study investigated the effects of a synbiotic combination (Syn) of Lactobacillus gasseri 505 (505) and Cudrania tricuspidata leaf extract (CT) on the hypothalamic-pituitary-gonadal axis in mice under chronic stress. Unpredictable chronic mild stress (UCMS) significantly increased the serum levels of corticosterone, however, treatment with Syn suppressed UCMS-induced increases. Histopathological analysis of the testes showed that these organs experienced some damage during UCMS, but this was repaired following treatment with Syn. Similarly, the transcription levels of gonadotropin-releasing hormone (GnRH), GnRH receptor, and gonadotropins, moreover, testicular development (i.e., Adam5, Adam29, and Spam1) - and steroidogenesis (i.e., Lhr, Egfr, and StAR) -related genes were significantly downregulated by UCMS. These UCMS-induced changes were inhibited by the administration of Syn, which was confirmed by the results of in situ hybridization analysis. These results suggest that the administration of Syn could attenuate the testicular dysfunctions induced by UCMS.

Cudrania tricuspidata Combined with Lacticaseibacillus rhamnosus Modulate Gut Microbiota and Alleviate Obesity-Associated Metabolic Parameters in Obese Mice.

The aim of the presented study was to investigate the synbiotic effects of L. rhamnosus 4B15 and C. tricuspidata extract administration on the gut microbiota and obesity-associated metabolic parameters in diet-induced obese mice. Thirty-one 6-week-old male C57BL/N6 mice were divided into five diet groups: normal diet (ND, n = 7) group; high-fat diet (HFD, n = 6) group; probiotic (PRO, n = 5) group; prebiotic (PRE, n = 7) group; and synbiotic (SYN, n = 6) group. After 10 weeks, the percent of fat mass, serum triglyceride, and ALT levels were significantly reduced in SYN-fed obese mice, compared with other treatments. SYN treatment also modulated the abundance of Desulfovibrio, Dorea, Adlercreutzia, Allobaculum, Coprococcus, unclassified Clostridiaceae, Lactobacillus, Helicobacter, Flexispira, Odoribacter, Ruminococcus, unclassified Erysipelotrichaceae, and unclassified Desulfovibrionaceae. These taxa showed a strong correlation with obesity-associated indices. Lastly, the SYN-supplemented diet upregulated metabolic pathways known to improve metabolic health. Further investigations are needed to understand the mechanisms driving the synbiotic effect of C. tricuspidata and L. rhamnosus 4B15.

Antimicrobial activity of fermented Maillard reaction products, novel milk-derived material, made by whey protein and Lactobacillus rhamnosus and Lactobacillus gasseri on Clostridium perfringens.

OBJECTIVE: The objective of this study was to evaluate the antimicrobial effects of fermented Maillard reaction products made by milk proteins (FMRPs) on Clostridium perfringens (C. perfringens), and to elucidate antimicrobial modes of FMRPs on the bacteria, using physiological and morphological analyses. METHODS: Antimicrobial effects of FMRPs (whey protein plus galactose fermented by Lactobacillus rhamnosus [L. rhamnosus] 4B15 [Gal-4B15] or Lactobacillus gasseri 4M13 [Gal-4M13], and whey protein plus glucose fermented by L. rhamnosus 4B15 [Glc-4B15] or L. gasseri 4M13 [Glc-4M13]) on C. perfringens were tested by examining growth responses of the pathogen. Iron chelation activity analysis, propidium iodide uptake assay, and morphological analysis with field emission scanning electron microscope (FE-SEM) were conducted to elucidate the modes of antimicrobial activities of FMRPs. RESULTS: When C. perfringens were exposed to the FMRPs, C. perfringens cell counts were decreased (p<0.05) by the all tested FMRPs; iron chelation activities by FMRPs, except for Glc-4M13. Propidium iodide uptake assay indicate that bacterial cellular damage increased in all FMRPs-treated C. perfringens, and it was observed by FE-SEM. CONCLUSION: These results indicate that the FMRPs can destroy C. perfringens by iron chelation and cell membrane damage. Thus, it could be used in dairy products, and controlling intestinal C. perfringens.

Protective Effects of Milk Casein on the Brain Function and Behavior in a Mouse Model of Chronic Stress.

Chronic stress is a major cause of mental health problems and primary medical issues. Milk has been studied for its stress-reducing effects. Tryptophan, which is abundant in milk, is a precursor of the neuroactive compounds serotonin and melatonin. This study investigated the preventive effects of milk casein on brain dysfunction and anxiety-like behavior induced by chronic stress. Mice were exposed to unpredictable chronic mild stress (UCMS) and milk casein was administered for 10 weeks. Milk casein significantly reduced stress-induced changes in serum corticosterone and serotonin levels. The negative effects of UCMS on the expression of proteins associated with neuroendocrine function, neurodegeneration, neuronal inflammation, and barrier function of the blood-brain barrier were statistically normalized by casein treatment. Pretreatment with casein significantly prevented anxiety-like behavior induced by UCMS. These results suggest that milk casein has the potential to prevent stress-induced brain dysfunction and anxiety-like behavior.

Fermented Maillard reaction products attenuate stress-induced testicular dysfunction in mice.

Chronic stress can cause psychological diseases and affect male fertility and the reproductive system. Maillard reaction of milk proteins improves their functional and nutritional properties through modification of proteins. Previously, we determined that Maillard reaction product (MRP) from milk casein and MRP fermented (FMRP) with Lactobacillus rhamnosus 4B15 (4B15) had anti-anxiolytic effects in mice under chronic stress. Therefore, we aimed to investigate the effects of MRP and FMRP on chronic stress-induced testicular dysfunction in mice through quantitative real-time PCR (qRT-PCR) and in situ hybridization analysis. Mice were pretreated with MRP and FMRP for 10 wk; simultaneously, from the third week of the experimental period, they were exposed to unpredictable chronic mild stress (UCMS) for 7 wk. The expression levels of the luteinizing hormone subunit ß (Lhb) and follicle-stimulating hormone subunit ß (Fshb) were remarkably reduced after exposure to UCMS. However, treatment with MRP and FMRP inhibited the UCMS-induced reduction, with FMRP showing especially significant inhibition. Moreover, the expression of steroidogenesis-related genes [luteinizing hormone receptor (Lhr), follicle-stimulating hormone (Fshr), 3-ß hydroxysteroid dehydrogenase 2 (Hsd3b2), and steroidogenic acute regulatory protein (StAR)] were significantly reduced in response to UCMS. In contrast, the transcript levels of these genes were highest in the MRP-treated mice. Mice pretreated with FMRP also exhibited higher levels of gene expression compared with the nonstressed mice. Moreover, UCMS significantly downregulated the expression of genes associated with testicular function [i.e., a disintegrin and metallopeptidase domain 5 (Adam5), Adam29, bone morphogenetic protein 2 (Bmp2), tektin 3 (Tekt3), and sperm adhesion molecule 1 (Spam1)]. However, the administration of MRP and FMRP prevented the UCMS-induced reduction in the expressions of above genes. The localization of Lhr, Srd5a2, Adam29, and Spam1 was confirmed by in situ hybridization analysis and the results were consistent with those of qRT-PCR. Consequently, these results indicated that MRP and FMRP, manufactured by the heat treatment of milk casein and fermentation with probiotic 4B15, have the potential to prevent chronic stress-induced testicular dysfunction.

Anti-Inflammatory Effect of a Peptide Derived from the Synbiotics, Fermented Cudrania tricuspidata with Lactobacillus gasseri, on Inflammatory Bowel Disease.

The objective of this study was to evaluate the effects of peptides derived from synbiotics on improving inflammatory bowel disease (IBD). Five-week-old male C57BL/6 mice were administered with dextran sulfate sodium (DSS) via drinking water for seven days to induce IBD (IBD group). The mice in the IBD group were orally administered with PBS (IBD-PBS-positive control), Lactobacillus gasseri 505 (IBD-Pro), fermented powder of CT extract with L. gasseri 505 (IBD-Syn), ß-casein: LSQSKVLPVPQKAVPYPQRDMP (IBD-Pep 1), or α s2-casein: VYQHQKAMKPWIQPKTKVIPYVRYL (IBD-Pep 2) (both peptides are present in the synbiotics) for four more days while inducing IBD. To confirm IBD induction, the weights of the animals and the disease activity index (DAI) scores were evaluated once every two days. Following treatment of probiotics, synbiotics, or peptides for 11 days, the mice were sacrificed. The length of the small and large intestines was measured. The expression of the proinflammatory cytokines IL-1ß, IL-6, TNF-α, and COX-2 in the large intestine was measured. Large intestine tissue was fixed in 10% formalin and stained with hematoxylin and eosin for histopathological analysis. The body weights decreased and DAI scores increased in the IBD group, but the DAI scores were lower in the IBD-Pep 2 group than those in the IBD group treated with PBS, Pro, Syn, or Pep 1. The lengths of the small and large intestines were shorter in the IBD group than in the group without IBD, and the expression levels of the proinflammatory cytokines were lower (p < 0.05) in the IBD-Pep 2 group than those in the IBD-PBS-positive control group. In addition, histopathological analysis showed that IBD was ameliorated in the Pep 2-treated group. These results indicate that Pep 2 derived from α s2-casein was effective in alleviating IBD-associated inflammation. Thus, we showed that these peptides can alleviate inflammation in IBD.

Cancer-protective effect of a synbiotic combination between Lactobacillus gasseri 505 and a Cudrania tricuspidata leaf extract on colitis-associated colorectal cancer.

Previously, a synbiotic combination of probiotic Lactobacillus gasseri 505 (LG) and a new prebiotic, Cudrania tricuspidata leaf extract (CT) in fermented milk, designated FCT, showed an in vitro immunomodulatory effect and antioxidant activity. Although synbiotic combination might have cancer-protective effects, these activities have not been fully validated in vivo. Ten-week treatment of LG, CT, or FCT to azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colitis-associated colorectal cancer (CAC) mouse model reduced both the incidence of colonic tumors and damage to the colonic mucosa effectively, suggesting a cancer-protective effect. To understand these, biomarkers associated with inflammation, colon barrier, apoptosis, and cancer cell proliferation were monitored in AOM/DSS group versus LG/CT/FCT groups. A synbiotic combination (FCT) down-regulated pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1ß, and IL-6) and inflammation-associated enzymes (iNOS and COX-2), and up-regulated anti-inflammatory cytokines (IL-4 and IL-10). In addition, colon barrier experiment revealed that biomarkers of mucus layer (MUC-2 and TFF3) and tight junction (occludin and ZO-1) were up-regulated. Subsequent apoptosis experiment showed that pro-apoptotic factors (p53, p21, and Bax) were up-regulated and anti-apoptotic factors (Bcl-2 and Bcl-xL) were down-regulated. Furthermore, comparative metagenome analysis of gut microbiota revealed that Staphylococcus decreased but Lactobacillus, Bifidobacterium, and Akkermansia increased, supporting their protective effects, accompanied by increased short-chain fatty acids (SCFAs). Taken together, the FCT administration showed cancer-protective effects by reducing the risk of colitis-associated colon cancer via regulation of inflammation, carcinogenesis, and compositional change of gut microbiota. Consequently, the synbiotic combination (FCT) could be a novel potential health-protective natural agent against CAC.

Glycated milk protein fermented with Lactobacillus rhamnosus ameliorates the cognitive health of mice under mild-stress condition.

This study aimed to investigate the effects of glycated milk casein (Gc) fermented with Lactobacillus rhamnosus 4B15 (FGc) on the intestinal microbiota and physiological and behavioral properties in mice under chronic stress. Mice were administered Gc or FGc for 10 weeks and then exposed to unpredictable chronic mild stress (UCMS) for 7 weeks. FGc administration restored alterations of gut microbiota induced by UCMS. Moreover, FGc significantly reduced the stress-induced increase in serum corticosterone and decrease in serotonin levels. Anxiety-like behaviors induced by UCMS were also significantly decreased in the FGc group. UCMS-induced dysregulation of gene and protein expression related to neuroendocrine function, neuronal development, and inflammation, and gut-blood-brain barrier function was controlled by FGc pre-treatment. These results strongly suggest the protective effects of FGc targeting of intestinal microbiota for abnormal brain activity, which is consistent with the view that FGc plays an important role in regulating stress-related gut-brain axis disorders.

Synergistic effect of Lactobacillus gasseri and Cudrania tricuspidata on the modulation of body weight and gut microbiota structure in diet-induced obese mice.

High-fat diet (HFD)-induced obesity has been associated with alteration of gut microbiota alongside body weight gain. In this study, the synbiotic effect of Lactobacillus gasseri 505 (LG) and Cudrania tricuspidata (CT) in HFD-induced mice was revealed. After feeding mice with high-fat diet for 10 weeks, combination of LG and CT (LG_CT) exhibited the greatest reduction in the final body weight (11.9%). Moreover, microbial diversity significantly increased, and Principal Coordinate Analysis (PCoA) revealed that the LG_CT group showed closer cluster to NORM. At phylum level, the Firmicutes/Bacteroidetes (F/B) ratio increased in HFD, and the abundance of Bacteroidetes was restored by LG and CT. At genus level, notable changes in Alistipes, Desulfovibrio, Bilophila, and Acetatifactor were observed. Helicobacter elevated to 16.2% in HFD and diminished dramatically to less than 0.01% in LG and/or CT. At species level, L. gasseri increased after the administration of LG (0.54%) and LG_CT (1.14%), suggesting that LG may grow and colonize in the gut and CT can function as a prebiotic. Finally, functional analysis revealed certain metabolic factors correlated with body weight and gut microbiota. This study serves as a potential basis for the application of L. gasseri 505 and C. tricuspidata in the prevention and treatment of diet-induced obesity.Key Points • Combination of L. gasseri (LG) and C. tricuspidata (CT) reduced body weight gain.• Microbial diversity significantly increased in LG_CT treatment.• Abundance of microorganisms involved with leanness increased in LG, CT, and LG_CT.• Body weight is associated with some metabolic functions of gut microbiota.

A synbiotic combination of Lactobacillus gasseri 505 and Cudrania tricuspidata leaf extract prevents hepatic toxicity induced by colorectal cancer in mice.

Colorectal cancer (CRC) is known to be a life-threatening disease and commonly leads to metastasis in the liver. Fermented milk acts as an effective carrier for probiotic strains, whose consumption improves host health. Our previous study indicated that fermented milk that included a synbiotic combination of Lactobacillus gasseri 505 (505) and Cudrania tricuspidata leaf extract (CT) resulted in significantly greater anti-oxidative effects than fermented milk without CT. Therefore, we hypothesized that fermented milk containing CT and 505 (FCT) could result in hepatoprotective effects against CRC-induced liver metastasis. Liver inflammation and CRC were induced in male C57BL/6J mice, using azoxymethane/dextran sodium sulfate, and 505, CT, and FCT were administered to the 3 sample-treated 505, CT, and FCT groups, respectively, for 10 wk. The results showed that FCT treatment significantly reduced serum aspartate aminotransferase and alanine aminotransferase concentrations and elevated albumin concentrations. Moreover, the results of histological analysis showed that hepatic steatosis was notably reduced in the FCT group. Among the 3 sample-treated groups, the expression of mRNA associated with enzymes showing anti-oxidative activities, such as superoxide dismutase, catalase, and glutathione reductase, was the highest in the FCT-treated mice. In addition, FCT administration resulted in the greatest anti-inflammatory activity, as inflammatory marker levels (i.e., tumor necrosis factor-α, cyclooxygenase-2, myeloperoxidase, and nuclear factor kappa-light-chain enhancer of activated B cells) were significantly downregulated at the mRNA level and the expression of proteins associated with the nuclear factor kappa-light-chain enhancer of activated B cells and mitogen-activated protein kinase signaling pathways was suppressed by FCT. Therefore, this study demonstrated that fermented milk containing novel synbiotics has the potential to prevent hepatic toxicity induced because of CRC owing to its enhanced anti-oxidative and anti-inflammatory activities.

Enhanced Production of Galactooligosaccharides Enriched Skim Milk and Applied to Potentially Synbiotic Fermented Milk with Lactobacillus rhamnosus 4B15.

In the current study, we first investigated a method for directly transforming lactose into galacto-oligosaccharides (GOS) for manufacturing low-lactose and GOS-enriched skim milk (GSM) and then evaluated its prebiotic potential by inoculating five strains of Bifidobacterium spp. In addition, fermented GSM (FGSM) was prepared using a potentially probiotic Lactobacillus strain and its fermentation characteristics and antioxidant capacities were determined. We found that GOS in GSM were metabolized by all five Bifidobacterium strains after incubation and promoted their growth. The levels of antioxidant activities including radical scavenging activities and 3-hydroxy-3-methylglutaryl-CoA reductase inhibition rate in GSM were significantly increased by fermentation with the probiotic Lactobacillus strain. Moreover, thirty-nine featured peptides in FGSM was detected. In particular, six peptides derived from ß-casein, two peptides originated from αs1-casein and κ-casein were newly identified, respectively. Our findings indicate that GSM can potentially be used as a prebiotic substrate and FGSM can potentially prevent oxidative stress during the production of synbiotic fermented milk in the food industry.

Anti-inflammatory activities of Maillard reaction products from whey protein isolate fermented by Lactobacillus gasseri 4M13 in lipopolysaccharide-stimulated RAW264.7 cells.

Maillard reaction products formed from whey protein isolate (WPI) and sugar have been shown to have an anti-inflammatory effect in vitro. Here, we incubated WPI and galactose (GWA) in an aqueous solution at 65°C for 24 h to produce a glycated conjugate, which was then fermented using Lactobacillus gasseri 4M13 to obtain the fermented product (F-GWA). We demonstrated that F-GWA had an anti-inflammatory effect on lipopolysaccharide (LPS)-stimulated RAW264.7 cells. It reduced both LPS-stimulated nitric oxide production and LPS-stimulated increases in the gene expression levels of tumor necrosis factor-α and cyclooxygenase-2 in a dose-dependent manner. Furthermore, F-GWA inhibited the LPS-induced phosphorylation of extracellular signal-regulated kinase and c-Jun N-terminal kinase, members of the mitogen-activated protein kinase family. The glycation process was evaluated by measuring fluorescence intensity and the furosine concentration during the Maillard reaction to form GWA. The protein modifications of WPI were analyzed using MALDI-TOF tandem mass spectrometry. We found that the combination of the Maillard reaction and L. gasseri 4M13 fermentation increased the prebiotic properties of GWA as well as organic acid production, compared with the nonreacted WPI and galactose.