• Microbiology and Biotechnology Letters
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• v.35 no.2
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• pp.142-149
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• 2007

In this study, we investigated the biological activity of antioxidant and antibacterial activity of citrus by-product ferment. Hot water extracts and 80% methanol extracts from citrus byproduct of ferment were screened for antibacterial activity pathogenic bacteria by paper disc method. Among the various hot water extracts and 80% methanol extracts the Bacillus subtilis showed relatively strong antibacterial activities in the order. The reducing activity on the 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical and ${\cdot}OH$ radical scavenging potential were sequentially screened, in search for antioxidant activities of citrus by-product ferment.

• The Journal of Natural Sciences
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• v.15 no.1
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• pp.57-67
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• 2005

In Order to investigate the physiological role of thiol peroxidase in Bacillus subtilis, a thiol peroxidase (btpx) knock-out mutant was generated by homologous recombination. The growth of btpx knock-out mutant in aerobic condition showed a similar pattern with that of wild type of Bacillus subtilis 168/ But btpx knock-out mutant showed a retarded growht in response to oxidative stress such as $H_2O_2$, cumene hydroperoxide (CHP) treatments.

• Food Quality and Culture
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• v.3 no.1
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• pp.40-44
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• 2009

To evaluate the hypolipidemic effects of Cheonggukjang (CGJ), which is frequently used in Korea similar to Natto in Japan and Douchi in China like a dairy product, boiled soybeans were fermented with two Bacillus strains, B. subtilis and B. licheniforms, isolated from rice straw and their antihyperlipidemic effects of their products were investigated. Treatment with the CGJs significantly reduced blood triglyceride (TG) and total cholesterol (TC) levels and increased HDL cholesterol levels in Triton WR-1339-induced hyperlipidemic mice. The treatment of non-fermented soybeans alone also reduced blood TG and TC levels, but not significantly. Feeding the CGJs significantly lowered high blood TG and TC levels as well as body and epididymal mass weights in hyperlipidemic mice induced by the long-term feeding of a high-fat diet that increased blood HDL cholesterol levels. The B. subtilis-fermented CGJ products more potently reduced TG and TC levels, although the differences between the starters were not significant. These finding suggest that CGJ products may be effective as hypolipidemic foods by the synergistic interaction of soy and Bacillus strains.

• Applied Biological Chemistry
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• v.41 no.5
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• pp.342-348
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• 1998

A bacteria producing protease against soy protein was isolated from various traditional Me-Ju, in order to improve utililization and characteritics of soy protein hydrolysates reduced bitterness and advanced flavors. The optimal culture conditions for protease production was investigated. The isolated bacteria was identified as Bacillus subtilis by morphological and physiological charateristics and named Bacillus subtilis YG-95. The optimal culture condition of liquid medium for protease production by Bacillus subtilis YG-95 composed of 3.5% soluble starch, 3.0% soy protein isolate, 0.25%, dextrose, 0.5% NaCl, 0.25% $K_2HPO_4$ with on initial pH of 7.6, for 60 hrs at $45^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1227-1232
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• 2003

The solvent extracts of the aerial part of Artemisia capillaris extracted by using several solvents with different polarities were prepared and their antimicrobial activities were examined. The antimicrobial activities and cell growth inhibitions were investigated to each strain with the different concentrations of the aerial part of Artemisia capillaris Acetone extract showed the highest antimicrobial activity. Minimum inhibitory concentrations (MIC) for each strain were appeared to 20 mg/mL at Staphylococcus aureus and Bacillus subtilis, 40 mg/mL at Vibrio parahaemolyticus, and 80 mg/mL at Salmonella tyhimurium. The cell growth inhibitions were shown on Staphylococcus aureus, Bacillus subtilis, Vibrio parahaemolyticus, and Salmonella typhimurium for 48 hours. The acetone extract was further fractionated sequentially with hexane, chloroform, ethyl acetate, and butanol for purifying crude acetone extract. The solvent fraction of hexane, chloroform, ethyl acetate, and butanol showed the different antimicrobial activity, respectively.

• Journal of the Korean Society of Food Culture
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• v.32 no.6
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• pp.566-575
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• 2017

This study was conducted to screen for superior strains for preparation of Cheonggukjang and identify the optimal fermentation time based on fermentation of lentils by various Bacillus subtilis strains. Bacillus count was significantly high at 48 hrs of fermentation (9.22-9.51 log CFU/g). In addition, the pH was significantly high in the range of 7.60-7.92 at 48 hrs fermentation, and the reducing sugar content was significantly high (0.89-1.45). The amino-type nitrogen content and ammonia-type nitrogen content were significantly increased with fermentation time. Additionally, the amylase activity was significantly high (3.05-4.22) at 48 hrs of fermentation, as was the protease activity (4.80-5.63). Bacillus subtilis S3 (5.63), S4 (5.60) were higher than S1 (4.80), S2 (4.92). The viscous substances and DPPH radical scavenging activity increased at 48 hrs, then decreased. Sensory evaluation revealed that lentil Cheonggukjang fermented by S3 showed the highest scores in color, smell, savory taste, sweet taste, viscous substance and overall acceptability. Therefore, 48 hrs of fermentation should be suitable for lentil Cheonggukjang fermented by Bacillus subtilis S3.

• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.62-67
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• 1997

A potential biocontrol bacterium, YB-70 was isolated from a rhizosphere in suppressive soil and identified as a strain of Bacillus subtilis. In several biochemical and in vitro antibiosis tests on Fusarium solani with the culture filterates from B. subtilis YB-70, we found that antifungal mechanism of B. subtilis YB-70 was mediated by antibiotic substances produced from the bacterium. These antifungal substances were appeared to be hear-resistant, micromolecular, and ethy alcohol soluble. Antifungal agents produced by B. subtilis YB-70 showed strong inhibified against root-rotting fungi F. solani in in vivo pot test. An antifungal substance. YBS-1s, was purified from the culture broth of B. subtilis YB-70 by isoelectronic precipitation, silica gel column chromatography and Sephadex LH-20 column chromatography analysis by Fab-MASS, $^{1}$H-NMR, $^{13}$C-NMR, DEPT, and amino acid analyzer revealed that the YBS-1A was a peptide antibiotics of iturin class containing seven amino acids from five different groups, and the other(YBS-1B) was an analogue of iturin group composed of 11 amino acids with larher molecular weight of about 1, 500 dalton, which was lager than that of iturin A.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.919-923
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• 2005

A bacterium capable of poly(${\gamma}$-glutamic acid) production was isolated from nonpasteurized soy sauce. It was judged to be a variety of Bacillus subtilis and designated as B. subtilis C1. B. subtilis C1 produced ${\gamma}$-PGA in the absence of exogenous glutamic acid; therefore, it is a de novo PGA­producing bacterium. The product produced by B. subtilis C1 was characterized by amino acid analysis to be composed of solely glutamic acid. However, the $H^1-NMR$ spectra showed chemical shifts of glycerol protons in addition to those of authentic ${\gamma}$-PGA, indicating that the product is in fact a bioconjugate of ${\gamma}$-PGA. The finding is unique, because the microbial production of ${\gamma}$-PGA bioconjugate has never been reported before. The molecular mass of the product was over 10,000 kDa as determined by GPC, and $97\%$ of the product was D-glutamate, indicating that L-glutamate was converted to its D-form counterpart by B. subtilis C1.

• Food Science and Preservation
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• v.7 no.4
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• pp.414-417
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• 2000

Competent cell transformation of B. subtilis AC819 was carried out using phenotypic protease-defective(Npr-) DNA of B. subtilis MT-2. An obtained transformant, designated B. subtilis HL-1, was obtained by homologous DNA recombination. Phenotypes of B. subtilis HL-1 were characterized histidine requirement streptomycin-resistance, tetracyclin resistance and non-producing protease. Protoplast transformation frequency of B. subtilis HL-1 by plasmid pUB110 was higher than that of B. subtilis MT-2. From this result, B. subtilis HL-1 is useful for protease gene transformation and thermostable protease gene cloning as a host.

• Journal of Microbiology and Biotechnology
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• v.22 no.8
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• pp.1092-1100
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• 2012

Ten Bacillus strains with antimicrobial activities were isolated from Cheonggukjang produced at different parts in Korea. They all inhibited Listeria monocytogenes ATCC 19111 and nine inhibited Bacillus cereus ATCC 14579. Four isolates (W42, H27, SKE 12, and K21) showing strong inhibiting activities were identified as B. subtilis. B. subtilis W42 was the most inhibiting strain. The antimicrobial activity of culture supernatant from B. subtilis W42 was destroyed completely by proteinase K treatment, indicating that a bacteriocin was the responsible agent. The bacteriocin, Bac W42, was most stable at pH 7 and stable between pH 3-6 and 8-9. Bac W42 was stable up to $80^{\circ}C$. BHI (brain heart infusion) and TSB (tryptic soy broth) were the best media for the activity (320 AU/ml) followed by LB (160 AU/ml). Bac W42 was partially purified by column chromatographies. The specific activity was increased from 1,151.2 AU/ml to 9,043.5 AU/ml and the final yield was 26.3%. Bac W42 was 5.4 kDa in size as determined by SDS-PAGE. Bac W42 showed bactericidal activity against L. monocytogenes ATCC 19111.