• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5343-5350
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• 2015

This study aims to compare and analyze the antioxidant effect of Cheonggukjang's traditional fermentation strain, Bacillus subtilis NG24 which was a control of the study, in order to see the biological activity effect of the new strain, Bacillus amyloliquefaciens NBF11-1 that was first found in the surface of the bamboo stem, but hasn't been insufficiently researched. In the antioxidant activity experiment of the Cheonggukjang extract, the B.amyloliquefaciens NBF11-1 sample showed a significant increase in the total polyphenol extract content, compared to B.subtilis NG24(p=0.032). Also, compared to B.subtilis NG24, the sample containing B.amyloliquefaciens NBF11-1 showed a significant increase in SOD-like Activity, DPPH radical scavenging, and NO radical scavenging, as the concentration rose(p<.05). Additionally, $IC_{50}$ in each antioxidant activity experiment significantly decreased in the B.amyloliquefaciens NBF11-1 sample like SOD-like Activity(p=0.045), DPPH radical scavenging(p=0.041), and NO radical scavenging(p=0.019), compared to B.subtilis NG24.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.389-393
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• 2002

Among the bacterial strains isolated from chungkook-jang, Bacillus subtilis CH-1, Bacills circulans K-1 and Bacillus subtitis (natto) N-1, Bacillus subtitis CH-1 showed the highest productivity of biosufactant. A-medium was selected for the basal medium in the large scale production of biosurfactant, and modified to synthetic medium which containing 2% glucose, 0.3% soy peptone, and mineral salts. The surface tension was reduced to maximal value after 96 hr after fermentation, about the 43% of initial tension. Temperature and initial pH of medium was not critical factor for the biosurfactant production. The yield of crude biosurfactant was 6 g/L under the optimum condition.

• Journal of Mushroom
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• v.13 no.4
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• pp.305-309
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• 2015

In order to isolate compost-promoting bacteria with high activity of cellulase and xylanase, spent mushroom substrates with sawdust were collected from mushroom cultivation farm, Jinju, Gyeongnam in Korea. Among of the isolates, one strain, designated CA105 was selected by agar diffusion method. The strain CA105 was identified as members of the Bacillus subtilis by biochemical characteristics using VITEK 2 system. Comparative 16S rRNA gene sequence analysis showed that isolate CA105 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus subtilis with 16S rRNA gene sequence similarity of 98.9%. On the basis of its physiological properties, biochemical characteristics and phylogenetic distinctiveness, isolate CA105 was classified within the genus Bacillus subtilis, for which the name Bacillus subtilis CA105 is proposed. The cellulase and xylanase activity of B. subtilis CA105 was slightly increased according to bacterial population from exponential phase to stationary phase in growth curve for Bacillus sp. CA105.

• Microbiology and Biotechnology Letters
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• v.42 no.4
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• pp.393-401
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• 2014

A bacterium producing antimicrobial substance was isolated from cheonggukjang. The bacterium was identified as a strain of Bacillus subtilis by 16S rDNA sequencing and designated as Bacillus subtilis HH28. The antimicrobial substance produced from Bacillus subtilis HH28 was purified by 0-80% ammonium sulfate precipitation, DEAE-sepharose FF column chromatography, and Sephacryl S-200 HR gel chromatography. The molecular weight of the purified antimicrobial substance was estimated to be approximately 3,500 Da using Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis and direct detection analysis. Antimicrobial substance from B. subtilis HH28 not only inhibited B. cereus, but also Listeria monocytogenes and Vibrio parahaemolyticus. The purified antimicrobial substance was stable at $40-80^{\circ}C$, and between pH 2 and 8. Antimicrobial activity of the purified substance was completely destroyed by treatment of protease, proteinase K, and pronase E, indicating that it is proteinaceous.

• Microbiology and Biotechnology Letters
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• v.44 no.2
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• pp.185-193
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• 2016

A novel proteolytic bacterium was isolated from soil at Yeungnam University, South Korea. The strain, named FBL-1, was rod-shaped with a smooth surface. Biolog and API 50CHB test results revealed that strain FBL-1 was a Bacillus species. Based on 16S rDNA sequencing and chemotaxonomic characterization, the strain was identified as Bacillus subtilis because it had the highest homology with Bacillus subtilis subsp. subtilis NCIB 3610 (99.5%). In liquid culture at 37℃ with shaking at 200 rpm, fructose and yeast extract were found to be the best carbon and nitrogen sources, respectively, for cell growth and protease production. The highest protease activity (451.640 U/ml) was obtained when the strain was cultured in medium containing 20 g/l of fructose and 5 g/l of yeast extract. Although further studies are needed to characterize the protease and enhance its activity, the newly isolated protein-degrading B. subtilis FBL-1 can be applicable for the production of peptides and for the degradation of proteins in various industries.

• Food Science and Preservation
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• v.22 no.4
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• pp.545-552
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• 2015

This study investigated the quality characteristics of popped rice Doenjang prepared with different Bacillus strains (Bacillus subtilis KACC 15935, and Bacillus subtilis HJ18-9). The changes in the enzyme activity (protease, cellulase, and ${\alpha}$-amylase), amino-type nitrogen and ammonia-type nitrogen contents, and the reducing sugar were investigated during the fermentation period. Enzymes such as protease, cellulase, and a-amylase plays an important role in the changes in composition of nutrients, and in flavor and taste of popped rice Doenjang. Protease activities of the popped rice deonjang fermented with different Bacillus strains (control, B. subtilis KACC 15935, and B. subtilis HJ18-9) was in the range of 171.77-185.97 unit/g at the beginning of fermentation, and there were no significant differences among the samples. On the other hand, the protease activity in popped rice Doenjang fermented with B. subtilis HJ18-9 increased significantly up to $248.77{\pm}4.53unit/g$ at the end of fermentation (p<0.05). Cellulase activity and a-amylase activity of popped rice Doenjang in HJ18-9 was higher than these of other samples. After 56 days of fermentation, amino-type nitrogen in popped rice deonjang fermented with control, B. subtilis KACC 15935, and B. subtilis HJ18-9 increased significantly up to $174.99{\pm}3.70$, $166.59{\pm}1.40$, $225.39{\pm}3.70mg%$, respectively (p<0.05). These results suggested that B. subtilis HJ18-9 was a suitable starter for the preparation of soybean paste.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.66-71
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• 1996

To extend shelf life of cooked rice, main putrefactive microorganism isolated from cooked rice were identified by using the API 50 CHB kit and fatty acid analysis of the cell and antimicrobial activity of water extract of green tea was tested against isolated strains and some type of strains. The growths of Bacillus subtilis ATCC 6633, Salmonella typhimurium ATCC 14028, Bacillus cereus YUFE 2004 and Staphylococcus aureus YUFE 2087 were inhibited in broth containing 500 and 1000 ppm of green tea extract. Main putrefactive microorganisms of cooked rice were identified as Bacillus subtilis RHJ-I and Bacillus subtilis RHJ-II. Green tea extract of 500 and 1000 ppm level inhibited the growth of Bacillus subtilis RHJ-I only.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.704-709
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• 2006

The mucilage production and tyrosine content in soy milk cake (SMC) fermented by Bacillus firmus NA-1, Bacillus subtilis GT-D, and B. subtilis KU-A was improved by fortification with 10% defatted soybean flour. The fibrinolytic activity and consistency of the SMC were drastically increased by solid-state fermentation for 1 day. However, the consistency of the fermented SMC gradually decreased during fermentation for 3 days. Furthermore, the tyrosine content of the freeze-dried powder of SMC fermented by three Bacillus sp. was 9 times higher than that of unfermented SMC. The soybean proteins, including the 7S and 11S subunits, were partially digested during alkaline fermentation, producing lower molecular-weight peptides. The fibrinolytic enzyme produced in SMC fermented by B. firmus NA-l and B. subtilis KU-A exhibited higher thermal stability than that of B. subtilis GT-D fermentation. The powder obtained from B. subtilis GT-D fermentation had an ${\alpha}$-amylase activity and lower consistency compared to those of B. firmus NA-1 and B. subtilis KU-A. In addition, this powder contained 6.3% moisture content, 27% crude protein content and 9 units of fibrinolytic activity and proteolytic activity.

• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.285-291
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• 2008

A potential probiotics bacterial strain, CS90, was isolated from Korean soybean paste (doenjang). The strain CS90 showed antimicrobial activity against food-borne pathogenic bacteria including Salmonella enterica, Salmonella enteritids, Salmonella typhymurium, Bacillus cereus, Listeria ivanovii, Listeria. monocytogenes, Sthaphylococcus aureus, and Sthaphylococcus epidermidis and showed a significant survival rate of 35.7 to 57.8% under the artificial gastric acidic condition (pH 2 to 3). The strain CS90 was classified as Bacillus subtilis based on morphological, physiological, chemotaxonomic features and phylogenetic analysis based on 16S rDNA sequence and designated as B. subtilis CS90. B. subtilis CS90 can be used as a potential probiotics.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.593-598
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• 1994

A bacterium KL-57 which exhibited biosurfactant activity was isolated. This bacterium was identified as Bacillus subtilis. The biosurfactant-producing gene of B. subtilis KL-57 was cloned into R subtilis MI113 by using plasmid pTB523. The plasmid DNA from the clone was found to carry a 18 kb PstI insert. The biosurfactant-producing gene was cleaved into 4 fragments by SmaI, 3 fragments by PvulI or EcoRl, 4 fragments by PvulI and EcoRI double digestion, 5 fragments by AccI, and 2 fragments by KpnI, HindIII or BamHI. By subcloning the 18 kb Pstl insert, a 2.3 kb EcoRl fragment conferred the biosurfactant producing activity on B. subtilis cells. The 2.3 kb had one HindIII cleave site. But Two fragments, which corresponds HindIII/EcoRl termini, exhibited no biosurfactant activity.