• Food Science of Animal Resources
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• v.35 no.5
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• pp.604-610
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• 2015

We investigated the synergic anti-inflammatory activity of Gleditsia sinensis Lam. (GS) extract and Lactobacillus brevis KY21 both in vitro and in vivo. Western blot analysis and immunostaining showed that AKT phosphorylation that increased by the exposure of LPS were significantly decreased by the presence of either GS extract or L. brevis KY21. In addition, p65 intracellular transport was critically inhibited by GS extract and L. brevis KY21. We further studied these effects using an in vivo dextran sulfate sodium (DSS)-induced mouse model. Body weight, food intake, and clinical scores were dramatically decreased after treatment with DSS, whereas these effects were palliated by the addition of GS extract and L. brevis KY21. Importantly, transcription of genes encoding pro-inflammatory cytokines including IL-1β, TNF-α, and IFN-γ in mesenteric lymph nodes (MLN) and the spleen were increased by DSS treatment, whereas they were inhibited by the presence of GS extract and L. brevis KY21.

• Journal of Life Science
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• v.23 no.1
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• pp.44-54
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• 2013

To determine the potential function of Rhus javanica in Korean medicine, it was fermented with each strain of Lactobacillus spp. Each strain of Lactobacillus spp. was inoculated in lactobacilli MRS broth, and 5 mg/ml of methanol extract of Rhus javanica was added. In mouse hippocampal HT22 cells, ethyl acetate extract of R. javanica fermented with L. brevis KCTC 3498 induced heme oxygenase-1 expression and showed a significant cytoprotective effect on glutamate-induced oxidative damage. The cytoprotective effect was related to the transcription of the nuclear factor E2-related factor2 (Nrf2), which is responsible for the induction of heme oxygenase-1 within the nucleus. The antimicrobial, antioxidant, and heme oxygenase-1 expression activities of fermented R. javanica were measured after extraction with ethyl acetate. R. javanica fermented with L. plantarum subsp. plantarum KCTC 3108, L. fermentum KCTC 3112, and L. brevis KCTC 3498 had higher antioxidant activity than nonfermented R. javanica. The fermented R. javanica with L. plantarum subsp. plantarum KCTC 3108, L. casei KCTC 3109 after ethyl acetate extraction showed antibacterial activity against Bacillus subtilis PCI 219, Escherichia coli KCTC 1682, Shigella flexneri KCTC 2517, Vibrio parahaemolyticus KCTC 7471, and Pseudomonas aeruginosa KCTC 2004. An ethyl acetate extract of the fermented R. javanica with Lactobacillus brevis KCTC 3498 exhibited stronger antibacterial activity than a nonfermented one against strains of B. subtilis PCI 219, E. coli KCTC 1682, S. flexneri KCTC 2517, and V. parahaemolyticus KCTC 7471.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.541-550
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• 2020

The use of yeast assist kefir fermentation, but also can cause food spoilage if uncontrolled. Hence, in this study, the microbial composition of an existing commercial kefir starter was modified to produce a functional starter, where Lactobacillus acidophilus KCNU and Lactobacillus brevis Bmb6 were used to replace yeast in the original starter to produce non-yeast kefir-like fermented milk. The functional starter containing L. acidophilus KCNU and L. brevis Bmb6 demonstrated excellent stability with 10¹⁰ CFU/g of total viable cells throughout the 12 weeks low-temperature storage. The newly developed functional starter also displayed a similar fermentation efficacy as the yeast-containing control starter, by completing the milk fermentation within 12 h, with a comparable total number of viable cells (10⁸ CFU/mL) in the final products, as in control. Sensory evaluation revealed that the functional starter-fermented milk highly resembled the flavor of the control kefir, with enhanced sourness. Furthermore, oral administration of functional starter-fermented milk significantly improved the disease activity index score by preventing drastic weight-loss and further deterioration of disease symptoms in DSS-induced mice. Altogether, L. acidophilus KCNU and L. brevis Bmb6 have successfully replaced yeast in a commercial starter pack to produce a kefir-like fermented milk beverage with additional health benefits. The outcome of this study provides an insight that the specific role of yeast in the fermentation process could be replaced with suitable probiotic candidates.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.450-459
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• 2017

This study evaluated the effects of culture conditions, including carbon and nitrogen sources, L-monosodium glutamate (MSG), and initial pH, on gamma-aminobutyric acid (GABA) production by Lactobacillus brevis HYE1 isolated from kimchi, a Korean traditional fermented food. L. brevis HYE1 was screened by the production analysis of GABA and genetic analysis of the glutamate decarboxylase gene, resulting in 14.64 mM GABA after 48 h of cultivation in MRS medium containing 1% (w/v) MSG. In order to increase GABA production by L. brevis HYE1, the effects of carbon and nitrogen sources on GABA production were preliminarily investigated via one-factor-at-a-time optimization strategy. As the results, 2% maltose and 3% tryptone were determined to produce 17.93 mM GABA in modified MRS medium with 1% (w/v) MSG. In addition, the optimal MSG concentration and initial pH were determined to be 1% and 5.0, respectively, resulting in production of 18.97 mM GABA. Thereafter, response surface methodology (RSM) was applied to determine the optimal conditions of the above four factors. The results indicate that pH was the most significant factor for GABA production. The optimal culture conditions for maximum GABA production were also determined to be 2.14% (w/v) maltose, 4.01% (w/v) tryptone, 2.38% (w/v) MSG, and an initial pH of 4.74. In these conditions, GABA production by L. brevis HYE1 was predicted to be 21.44 mM using the RSM model. The experiment was performed under these optimized conditions, resulting in GABA production of 18.76 mM. These results show that the predicted and experimental values of GABA production are in good agreement.

• Food Science of Animal Resources
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• v.41 no.6
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• pp.967-982
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• 2021

Probiotics are living microorganisms that, when administered in adequate amounts, provide a health benefit to the host and are considered safe. Most probiotic strains that are beneficial to human health are included in the "Lactic acid bacteria" (LAB) group. The positive effects of probiotic bacteria on the host's health are species-specific and even strain-specific. Therefore, evaluating the probiotic potential of both wild and novel strains is essential. In this study, the probiotic characteristics of Lactobacillus brevis KT38-3 were determined. The strain identification was achieved by 16S rRNA sequencing. API-ZYM test kits were used to determine the enzymatic capacity of the strain. L. brevis KT38-3 was able to survive in conditions with a broad pH range (pH 2-7), range of bile salts (0.3%-1%) and conditions that simulated gastric juice and intestinal juice. The percentage of autoaggregation (59.4%), coaggregation with E. coli O157:H7 (37.4%) and hydrophobicity were determined to be 51.1%, 47.4%, and 52.7%, respectively. L. brevis KT38-3 produced β-galactosidase enzymes and was able ferment lactose. In addition, this strain was capable of producing antimicrobial peptides against the bacteria tested, including methicillin and/or vancomycin-resistant bacteria. The cell-free supernatants of the strain had high antioxidant activities (DPPH: 54.9% and ABTS: 48.7%). Therefore, considering these many essential in vitro probiotic properties, L. brevis KT38-3 has the potential to be used as a probiotic supplement. Supporting these findings with in vivo experiments to evaluate the potential health benefits will be the subject of our future work.

• Journal of Animal Science and Technology
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• v.48 no.4
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• pp.503-512
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• 2006

This study was conducted to investigate the effects of dietary Lactobacillus brevis (3.4×108 CFU/g) supplementation on growth performance, DM and N digestibilities, blood cell counts and fecal odor emission compounds in growing pigs. Ninety six crossbred [(Landrace×Yorkshire)×Duroc] pigs with an initial BW of 24.60±1.28kg were used for 42-d feeding trial according to a completely randomized design. Three corn- soybean meal based dietary treatments included: 1) CON (basal diet); 2) LB1 (basal diet + Lactobacillus brevis 0.2%) and 3) LB2 (basal diet+Lactobacillus brevis 0.4%). There were three dietary treatments with eight replicate pens per treatment and four pigs per pen. Through the entire experimental period, ADG, ADFI and gain/feed had no significant differences among treatments(P>0.05). Nitrogen digestibility was increased in LB1 and LB2 treatments compared to CON treatment (linear effect, P<0.05), however, DM digestibility had no significant difference among all the treatments (P>0.05). The WBC, RBC and lymphocyte concentrations in whole blood were not affected by treatments (P>0.05). Fecal NH3N and H2S concentrations were significant decreased in LB2 treatment compared to CON treatment (linear effect, P<0.05). Fecal VFA (acetic acid and propionic acid) concentration was also reduced in LB2 treatment compared to CON treatment (linear effect, P<0.05). In conclusion, Lactobacillus brevis (3.4×108 CFU/g) supplementation at the level of 0.4% can improve nitrogen digestibility and decrease the concentrations of fecal odor emission compounds in growing pigs.

• Journal of Microbiology and Biotechnology
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• v.29 no.11
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• pp.1745-1748
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• 2019

Gamma-aminobutyric acid (GABA) plays important roles in host physiology. However, the effects of GABA are greatly restricted due to its low bioavailability in the human body. Here, a high acid-tolerance GABA-producing strain, Lactobacillus brevis Bmb5, was isolated from kimchi. Bmb5 converted glutamate to GABA (7.23 ± 0.68 ㎍/μl) at a rate of 72.3%. The expression of gadB gene, encoding the enzyme involved in the decarboxylation of glutamate to GABA, was decreased upon incubation. Our findings indicate GABA production in Bmb5 is not directly correlated with gadB gene expression, providing new insight into the mechanisms underlying GABA production in Lactobacillus.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.334-344
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• 2014

The objective of this study was to evaluate the microbiological and physicochemical characteristics, and the antagonistic activity against Helicobacter pylori ATCC 43504, of yogurt fermented with the lactic acid bacteria from Baikkimchi kept under cold storage. The viable cell counts, titratable acidity, viscosity, and total solid content of the yogurt were different according to the bacterial strains used for fermentation. There was no significant change (P>0.05) in the various properties of refrigerated yogurt. Among the tested strains, the strongest resistance against artificial gastric juice and bile salt was found for Lactobacillus brevis BK11 and Lactobacillus paracasei BK57. Due to high lactic acid levels obtained from these two lactic acid bacteria, yogurt may show good anti-Helicobacter effects according to the time-kill assay. In particular, yogurt fermented with L. brevis BK11 significantly reduced the number of H. pylori adhering to gastric epithelial AGS cells and the urease activity of this pathogen (P<0.05).

• Food Science and Preservation
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• v.7 no.3
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• pp.321-325
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• 2000

This study was conducted to investigate the effect of the extracts (water, 70% ethanol and ethylacetate) from dandelion (Traxancum platycarpum D.) leaf and root on the inhibitory activities of Leuconostoc mesenteroides, Lactobacillus brevis, Lactobacillus plantarum and Lactobacillus acidophilus. And also, the amounts of gas formation from kimchi with different concentration of the ethylacetate extracts (EE) were analyzed. EE of dandelion leaf inhibited the growth of Leuc. mesenteroides and L. acidophilus, and L. brevis by 50 and 33% at concentration of 0.5%, respectively. But no affected in L. plantarum estimated by pH, acidity, turbidity and clear zone. And no difference was founded in leaf and root. Gas was formed from the soaking day to 5-6 days of fermentation at $20^{\circ}C$, and the accumulated gas volumes were 80 ml/100 g in control, 30 ml/100 g in 0.5% EE, 8 ml/100 g in 1.0% EE.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.814-821
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• 2000

In order to investigate the possible use of omija extract as natural preservatives for nabak kimchi omija extract was tested for antioxidation and electron-donating ability and further more antimicrobial activites against lactic acid bacteria of nabak kimchi. The concentration of the test sample used were 0.5, 1.0, 1.5, 2.0%. Antioxidative activity measured the TBA value, when omija extract concentration % is higher the antioxidation effect were more evident with the increased omija extract concentrations, and showed a high electron donating activity more than 1.0%. As the result of isolated lactic acid bacteria from nabak kimchi the primary separation tool 117 strains, of these 4 strains which had excellent growth and a strong acid formation capability was selected the second time and Lactobacillus brevis, Lactococcus faecalis, Leuconostoc mesenteriodes, Lactobacillus palantarum were identified. After measuring the antimicrobial activity of the four lactid acid bacteris, except Lactobacillus brevis the other three bacteria showed strong antimicrobial activities. The results suggest the possible use of the omija extract as natural preservative for nabak kimchi.