• Microbiology and Biotechnology Letters
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• v.21 no.5
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• pp.486-493
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• 1993

A gram(+) bacteria that produced microbial flocculant was isolated from soil and classified as a Bacillus species and named as Bacillus sp. A56. The culture conditions of the strain for fluocculant production were studied in a shake flask. Optimum temperature and initial pH for flcculant production were 30C and 6.5, respectively. The optimized medium has gollowing composition: glucose 20g/l, NH4NO3 0.5g/l, K2HPO4 1.0g/l, KH2PO4 0.8g/l, MgSO4.7H2O 0.2g/l, MnSO4.4-6H2O 0.3g/l, CaCO3 0.5g/l, yeast extract 0.3g/l, tryptone 0.3g/l in tap water.

• Microbiology and Biotechnology Letters
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• v.20 no.3
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• pp.344-347
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• 1992

Simultaneous liquefaction and cyclodextrin (CD) production were conducted on potato starch using cyclomaltodextrin glucanotransferase (CGTase) from a mutant strain MNNG 8 of Bacillus stearothermophilus No. 239. A high concentration (30%) of potato starch was converted to cyc1o-dextrins (CDs) with 29% yield in the conditions of pH 6.0, temperature $80^{\circ}C$, 4.3 mM $CaCl_2$, CGTase addition of 3.0 dextrinizing activity unit (DAU) at $40^{\circ}C$/g starch.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.390-396
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• 1995

Bacillus sphaericus 1593 is a larvicidal toxin-producing mosquitocidal bacterium. The toxin contains a parasporal crystalline inclusion which is composed of a protein that is activated under alkaline condition. To enhance alkaline environment around toxin protein, cryptic plasmid cured, B. sphaericus 1593 was transformed by the Bacillus pasteurii urease gene which generate ammonia from urea. Transformant produced urease at about 80% more than wild type strain. B. sphaericus 1593, and the urease gene was stably maintained. It also produced crystalline toxin protein at the same level as the wild type strain B. sphaericus 1593.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.169-170
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• 2018

Clindamycin resistant Bacillus licheniformis 14ADL4 was isolated from doenjang, a Korean high-salt-fermented soybean food. Strain 14ADL4 contains a single circular 4,332,232 bp chromosome with a G + C content of 45.86%. The complete genome of strain 14ADL4 includes lmrA and lmrB homologs may confer resistance to clindamycin.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.219-222
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• 2000

To produce and utilize microbial cyclomaltodextrinase being industrially useful, we isolated an alkalophilic Bacillus strain from soil which was capable of degrading cyclodextrins. The newly isolated strain was aerobic, gram-positive, spore-forming, motile, rod shape(0.2~0.4$\times$1.4~4.4 $\mu\textrm{m}$), and 35.8 mol% of DNA base composition. Based on its morphological, phisiological, and biochemical properties, it was identified as alkalophilic Bacillus sp. KJ-133 and cultivated well in the ranges of $30~40^{\circ}C$ and pH 8.0~9.0 . The cyclomaltodextrinase of the strain showed maximal production after 48h of cultivation at $37^{\circ}C$, and the activity was inhibited by Ag2+, Hg2+, Cu2+, and p-chloromercuribenzoate.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.322-328
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• 1995

A thermophilic bacteria showing proteolytic activity against defatted soybean was isolated from soil. It was identified as Bacillus amyloliquefaciens based on its morphological and physiological characteristics. The Bacillus amyloliquefaciens NS 15-4 was cultivated at 50$\circ$C by rotary shaking in a medium containing defatted soybean. An extracellular protease from this strain was purified to homogeneity by ammonium sulfate precipitation, ion exchange, and hydrophobic interaction chromatographies. The molecular weight of the enzyme was estimated to be approximately 30,000 by SDS-PAGE and the N-terminal amino acid sequence of the enzyme was turned out to be AQSVPYGISQIKAPA. The optimum temperature and pH for the enzyme reaction were 60$\circ$C and 11, respectively, and its thermostability was increased by the addition of calcium ion. The enzyme was inactivated by phenylmethylsulfonylfluoride, suggesting it be a serine protease. Comparing with other commercial proteases, the enzyme showed relatively high proteolytic activity against defatted soybean, a water-insoluble protein substrate.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.419-426
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• 2015

The aims of this study were to isolate spore-forming Bacillus strains that exhibit high digestibility and anti-pathogenic bacteria toward feed for calves. Total 136 spore-forming strains were isolated from finished feeds and their ingredients. Among them, 93 strains were identified as Bacillus species when analyzed by 16S rRNA sequencing. For industrial use, three strains named as Bacillus licheniformis SHS14, B. subtilis LCB7, B. amyloliquefaciens LCB10 were selected after evaluating the industrial standards that are related with heat and acid resistance, enzyme activities, and anti-pathogenic activities against Samonella dublin ATCC15480 and E. coli K99. After each culture, 3 selected strains were mixed together at 1:1:1 (v/v/v) ratio and then prepared as the mixed starter culture for feeding. The changes in microbial community were analyzed via 16S rRNA metagenomics. The initial community ratio among three strains was maintained even after manufacturing into final products. Also, in vitro, enzymatic and anti-pathogenic activities were almost same as those when cultured in single culture, and results of anti-pathogenic activities conducted with calves showed 90% activities against lincomycin, which would be indicative of a promising feed starter.

• Microbiology and Biotechnology Letters
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• v.9 no.3
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• pp.145-152
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• 1981

Microorganisms from the waste water of starch industry, were isolated and a strain, Y-124, possessing a powerful enzymic activity was selected and identified as a member of the genus Bacillus. The ideal cultural condition for the formation of $\alpha$-amylase form Bacillus Y-124 and its preservation was investigated in connection with the biotechnological and industrial approach to the bulk enzyme production. High yield of $\alpha$-amylase was observed in medium containing casein as well as calcium pantothenate in this work. Calcium ions were found to have an effect in forming this particular enzyme. Ammonium phosphate dibasic was an important inorganic nitrogen source for the formation of $\alpha$-amylase. And preservation of this enzyme was greatly affected by calcium or sodium salts. The addition of calcium carbonate or sodium sulfate presented the most effective result for the prevention of its denaturation to various factors. The above data was obtained with crude enzyme preparation.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.188-193
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• 2001

To evaluate antimicrobial activities of chongkukjang slime fermented by different strains, growth characteristics were compared using various standard microorganisms with addition of chongkykjang slime. Chonghkjang slime was prepared by fermenting cooked soybean after inoculating with Bacillus circulans K-1, Baciilus spp N-1 and Bacillus subtilis CH-1, respectively. Significant antimicrobial activity was observed by chongkukjang slime on gram positive bacteria (Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Micrococcus luteus), gram negative bacteria(Escherichia coli O157:H7, Salmonella Typhimurium, Pseudomonas fluorescens), and yeast (Pichia membranaefaciens, Saccharomyces cerevisiae, Candida albicans). In case of B. cereus growth inhibition of 80% was achieved by the addition of chongkukjang slime; on the contrary, to Escherichia coli O157:H7 only 20% inhibition was observed. Slime from Bacillus subtilis CH-1, in particular, inhibition of 40% toward bacteria and yeast, whereas slime from Bacillus circulans K-1, Bacillus spp N-1 showed only 20% inhibition.

• Microbiology and Biotechnology Letters
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• v.10 no.4
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• pp.259-265
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• 1982

These experiments were conducted to investigate the hydrolysis products on the various oligosaccharides of Bacillus cirulans F-2 $\alpha$-amylase, and the hydrolysis rate on the various raw starches of Bacillus circulans F-2 $\alpha$-amylase, Bacillus amylotiquefaciens $\alpha$-amylase and Rhizopus niveus glucoamylase. The results obtained were as follows : 1. Maltotetraose, maltopentaose, maltohexaose, maltoheptaose and maltooctaose were hydrolyzed, but maltose and maltotriose were not hydrolyzed by Bacillus circulans F-2 $\alpha$-amylase. Among maltotetraose, maltopentaose, maltohexaose, maltoheptaose and maltooctaose, especially maltotetraose was hydrolyzed weakly by Bacillus circulans F-2 $\alpha$-amylase. 2. The Hydrolysis rate of oyster glycogen was slightly lower than soluble starch, amylose and amylopectin. 3. The hydrolysis rate of com starch was higher in shaking incubation than in stationary incubation, but the hydrolysis rate of potato starch was not definite according to kinds of enzyme. 4. On com, rice, arrowroot, high amylose corn, banana, sago, yam and potato starch, Bacillus circulans F-2 $\alpha$-amylase exhibited a remarkably higher hydrolysis rate than Bacillus amyloquefaciems $\alpha$-amylase and Rhizopus niveus glucoamylase.