• Journal of the Korean Chemical Society
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• v.51 no.1
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• pp.51-55
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• 2007

The fatty acid composition of thiocyanate utilizing Bacillus brevis isolated from carbonization wastewater was determined by Gas Chromatography and the results were analyzed. In addition to the saturated and unsaturated straight chain fatty acids this B. brevis strain contained a hydroxy fatty acid. The hydroxy fatty acids in general are shown to be interesting chemotaxonomic markers of bacteria. Cyclopropane fatty acids are totally absent in this strain. A comparison of the fatty acid composition of this strain with B-33 and B-34 strains of Bacillus brevis shows that there are deviations among these strains. The deviation in Bacillus brevis could be due to the stress effect of thiocyanate. This result supports that fatty acid synthesis depends highly on the environment.

• Journal of Microbiology and Biotechnology
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• v.23 no.10
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• pp.1422-1427
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• 2013

Scutellaria baicalensis (SB), a traditional herb with high pharmacological value, contains more than 10% flavone by weight. To improve the biological activity of flavones in SB, we aimed to enhance the bioconversion of baicalin (BG) to baicalein (B) and wogonoside (WG) to wogonin (W) in SB during fermentation using beta-glucuronidase produced from Lactobacillus brevis RO1. After activation, L. brevis RO1 was cultured in milk containing SB root extract with various carbon or nitrogen sources at $37^{\circ}C$ for 72 h. During fermentation, the growth patterns of L. brevis RO1 and changes in the flavone content were assessed using thin-layer chromatography and high-performance liquid chromatography. After 72 h of fermentation, the concentrations of B and W in the control group increased by only 0.15 and 0.12 mM, respectively, whereas they increased by 0.57 and 0.24 mM in the fish peptone group. The production of B and W was enhanced by the addition of 0.4% fish peptone, which not only improved the growth of L. brevis RO1 (p < 0.001) but also enhanced the bioconversion of flavones. In conclusion, the bioconversion of flavones in SB may provide a potential application for the enhancement of the functional components in SB.

• Journal of the Korean Society of Food Culture
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• v.17 no.2
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• pp.165-170
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• 2002

In order to economically utilize dough with B. longum, B. infantis and B. brevis as a bread improver, aerotolerance, ${\alpha}-galactosidase$ activity, organic acids, farinograph and extensograph of dough were investigated. In aerotolerance of Bifidobacterium sp., B. longum was highest among tested starters, followed by B. infantis. The ${\alpha}-galactosidase$ activity was highest in the B. longum among tested starters. In organic acids, the contents of lactic acid and acetic acid were the highest in the among tested starters, followed by B. infantis. In farinograms of dough, water absorption and peak time were highest in the B. brevis among tested dough. Extensogram showed that the area increased remarkably in B. longum and B. infantis at 135min of fermentation. Extensibility and resistance to extension of dough were highest in the B. infantis among the dough, followed B. longum.

• Microbiology and Biotechnology Letters
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• v.50 no.3
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• pp.319-327
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• 2022

γ-Aminobutyric acid (GABA) is a multi-functional compound with broad applications for food industry. GABA producing bacteria were isolated from cabbage kimchi. Among them, B737 was the best GABA producer when culture supernatants were analyzed by TLC. B737 was identified as Levilactobacillus brevis by 16S rRNA gene sequencing. Its glutamate decarboxylase (GAD) gene was cloned by PCR and the nucleotide sequence determined. B737 GAD consisting of 485 amino acids is the largest in size among GADs reported from LAB so far. gadB from L. brevis B737 was overexpressed in Escherichia. coli BL21(DE3) using pET26b(+).pET26b(+). The recombinant GAD was purified and its size was 55 kDa by SDS-PAGE. Maximum GAD activity was observed at pH 5 and 40℃ and the activity was dependent on pyridoxal 5'-phosphate. K_m and V_max of recombinant GAD were 6.2 ± 0.06 mM and 0.34 ± 0.002 mM/min, respectively. L. brevis B737 can be used as a starter for fermented foods with high GABA contents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.980-985
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• 1994

We investigated the quality of soybean paste(Doenjang) fermented by BAcillus brevis. The results obtained were as follows : soybean paste fermented by Bacillus brevis had alkaline pH and yellow ochre color. Dextrinizing activity was about 98 D.P. unit from 5th to 25th day of fermentation at 3$0^{\circ}C$ and after that day somewhat decreased . Saccharifying activity was respectively 6.1, 7.2, 6.8, 6.4 S.P. unit on 5, 15, 25 and 35th day of fermentation. Protease activity suddenly increased after 15th day of fermentation and was 250, 275, 299 unit on15, 25, 35 th day of fermentation , respectively. The most abundant free amino acid was found to be glutamic acid (561.8mg%) in soybean paste fermented by Bacillus brevis. In case of free sugar and non-volatile organic acid, fructose and oxalic acid showed highest content of 10.25mg% on 25th day and 12.20mg% on 15th day. The contents of free amino acids, free sugars, organic acids in soybean paste fermented by B.brevis were most abundant after 25 days of fermentation and this results were similar to that of traditional soybean paste. The odor of soybean paste fermented by Bacillus brevis was improved to be a nice soybean paste odor on 25th day of fermentation. However, sensory evaluation value of the taste of it decreased after 10 th day of fermentation.

• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.205-211
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• 2022

Probiotics can effectively modulate host immune responses and prevent gastrointestinal diseases. The objective of this study was to investigate the probiotic characteristics of Lactobacillus brevis KU15152 isolated from kimchi and its protective potential against intestinal inflammation induced by Staphylococcus aureus lipoteichoic acid (aLTA). L. brevis KU15152 exhibited a high survival rate in artificial gastric and bile environments. Additionally, the adhesion capability of the strain to HT-29 cells was higher than that of L. rhamnosus GG. L. brevis KU15152 did not produce harmful enzymes, such as β-glucuronidase, indicating that it could be used as a potential probiotic. The anti-inflammatory potential of L. brevis KU15152 was determined in HT-29 cells. Treatment with L. brevis KU15152 suppressed the production of interleukin-8 without inducing significant cytotoxicity. The downregulatory effects of L. brevis KU15152 were involved in the suppression of nuclear factor-kappa B activation mediated by the extracellular signal-regulated kinase and Akt signaling pathways. Collectively, these data suggest that L. brevis KU15152 can be used in developing therapeutic and prophylactic products to manage and treat aLTA-induced intestinal damage.

• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.9-17
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• 2021

A γ-aminobutyric acid (GABA)-producing microorganism was isolated from galchi (hairtail fish, Trichiurus lepturus) jeotgal, a Korean salted and fermented seafood. The G144 isolate produced GABA excessively when incubated in MRS broth containing monosodium glutamate (MSG, 3%, w/v). G144 was identified as Lactobacillus brevis through 16S rRNA and recA gene sequencing. gadB and gadC encoding glutamate decarboxylase (GAD) and glutamate/GABA antiporter, respectively, were cloned and gadB was located downstream of gadC. The operon structure of gadCB was confirmed by reverse transcription (RT)-polymerase chain reaction. gadB was overexpressed in Escherichia coli and recombinant GAD was purified and its size was 54.4 kDa as evidenced by SDS-PAGE results. Maximum GAD activity was observed at pH 5.0 and 40℃ and the activity was dependent on pyridoxal 5'-phophate. The K_m and V_max of GAD were 8.6 mM and 0.01 mM/min, respectively.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.465-471
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• 1997

The cyclodextrin glycosyltransferase (CGTase, EC 3.2.1.19) from Bacillus brevis CD162 was purified by precipitating with ammonium sulfate, DEAE-Sepharose CL-6B column chromatography and Sephadex G-150 column chromatography. The molecular mass and pI of the purified enzyme were estimated to be 74,000 and 6.3 by SDS-PAGE and isoelectric focusing, respectively. The purified enzyme was clearly identified as the CGTase by zymogram after SDS-PAGE. The optimum pH and temperature for the enzyme activity were 8.0 and $55^{\circ}C$, respectively. The enzyme was stable at the range of pH $5.5{\sim}9.0$, and up to $50^{\circ}C$. The amino acid sequence from the $NH_2-terminal$ of the purified CGTase was Ser-Val-Thr-Asn-Lys-Val-Asn-Tyr-Ser-Lys-Asp-Val-Ile-Tyr-Gln. The yields of the products from starch as the substrate were 1.3% for ${\alpha}-$, 33.9% for ${\beta}-$, and 9.7% for ${\gamma}-cyclodextrin$.

• Journal of Food Hygiene and Safety
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• v.21 no.3
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• pp.159-163
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• 2006

37 Bacillus spp strains(43.0%=37/86), and 18 B. cereus(20.9%=18/86) were isolated on 86 dried marine products. Each isolates were B. cereus 48.6%(18/37), B. mycoides 13.5%(5/37) B. coagulus 5.4%(2/37) B. firmus 5.4%(2/37), B. circulus 2.7%(1/37), B. stearothermophilus 2.7%(1/37), B. pumilus 2.7%(1/37) B. spp. 8.1%(3/37), and Brebacillus brevis 10.8%(4/37) etc.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.970-975
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• 2007

For the screening of ${\gamma}-aminobutyric$ acid (CABA)-producing bacteria, 86 bacterial strains which produce GABA were isolated from Kimchi and Salted fisk .Among these, three strains designated AML15, AML45-1, AML72 with relatively high GABA productivity were selecled by thin layer chromatography (TLC). To elucidate the relationship between isolated strains and the genus Lactobacillus, their 16S rDNA sequence were examined. The result of their DNA sequences showed 99% similarity with Lactobacillus brevis ATCC 367. On the basis of the these results, isolated strains were identified as Lactobacillus brevis and designated L. brevis AML15. In order to determine the optimum conditions for GABA production, the isolated strains were cultivated in pyridoxal phosphate (PLP) and monosodium glutami. acid (MSG). Results showed that L. brevis AML15 had the highest CABA productivity with 10,424 $nM/{\mu}l$ concentration in MRS broth containing 5% (w/v) MSG and 10 ${\mu}M$ PLP at pH 5.0. The results imply that L. brevis AML15 has the potential to be developed as a strain for GABA hyper-production.