• KSBB Journal
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• v.25 no.6
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• pp.520-526
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• 2010

In this work we have investigated the production of catalase from Bacillus sp. strains, which were screened and identified from soil. These strains were cultivated in shaking flasks with tryptic soy broth (TSB) at $30^{\circ}C$ and 200 rpm. Effects of the temperature and pH on the stability of the native catalase and whole cell viability were studied in the temperature range of $25-60^{\circ}C$ and the pH range of 7-13. Korean natural zeolite was added to culture medium and mixed with microorganisms for 24 hours. The native catalase maintained its activity over $50^{\circ}C$. The enzyme acitiviy of the catalase from Bacillus flexus BKBChE-3 was highest among the Bacillus sp. strains studied. Bacillus flexus BKBChE-3 and immobilized Bacillus cells have survived under extreme conditions of over $50^{\circ}C$ and pH 12. 60 mL of 10.5 mM $H_2O_2$ solution were entirely removed within 1 hour with catalase produced from Bacillus sp. on the flask. When Bacillus cells were immobilized on Korean natural zeolite, colony forming unit of Bacillus flexus BKBChE-3 was increased and high efficiency of hydrogen peroxide removal was observed.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.543-547
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• 1991

An alkalophilic microorganism, SH-8, was isolated from soil samples. It was a Grampositive, catalase-positive, spore-forming and motile rod which was capable of growth in aerobic condition at the initial pH 9.0 or above up to 11.0 and between 15 and $42^{\circ}C$ The characteristics of this strain resembled those of the Bacillus group of bacteria. The mutant, Bacillus sp. SH- 8M, was selected from Bacillus sp. SH-8 by U.V. mutagenesis and was able to grow at pH 6.9 up to 11.0. These two strains will be suitable for the comparative study on growth and enzyme production at various pH conditions.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.34-39
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• 1992

For the screening of new-functional and specific exopolysaccharide, a bacterium strain was isolated from soil through the two steps of screening. The isolated bacterium was identified as Bacillus polymyxa KS-1 according to the criteria of morphological, physiological, and chemical taxonomic analyses. The exopolysaccharide was composed of glucose:galactose: mannose and galactosamine in an approximate molar ratio of 1.00:0.36:1.02:1.10. The produced exopolysaccharide by Bacillus polymyxa KS-1 was found to be revealed new acidic polysaccharide which did not contain pentose, ketose, starch, and uronic acid.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.175-183
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• 1986

The isolate HL-15 of Bacillus thuringiensis had common biochemical characteristics of the 23 serovarieties of B. thuringiensis. The isolates formed round endotoxin crystals which killed insect larvae, showed independent serological H antigen to the 23 serotypes, and contained two defferect DNA elements with over 100 Mdaltons of molecular weights.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.57-62
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• 2001

Twelve antagonistic strains against Fusarium wilt of watermelon-rootstock gourd were selected from 54 bacterial isolates which were isolated from the rhizosphere of crop plants growing in various locations. They showed strong inhibitory effects on growth of Fusarium osysporum f. sp. niveum, the causal agent of watermelon-rootstock gourd Fusarium wilt. Among these antagonists, the isolate YJ-3 was the most pronounced in growth-promoting ability for watermelon-rootstock gourd. The growth of watermelon-rootstock gourd in bed soil inoculated with YJ-3 was better by 46 and 13% than those in commercial bed soil alone and in bed soil inoculated with commercial microbial inoculant, respectively. The antagonistic plant growth-promoting rhizobacterium, strain No. YJ-3, was identified as Bacillus sp. on MIDI system. Furthermore, Bacillus sp. YJ-3 showed antifungal activity on growth against Alternaria cucumerina, Botrytis cinerea, Colletotrichum orbiculare, Didymella bryoniae, Rhizoctonia solani and Fusarium oxysporum.

• Journal of Sericultural and Entomological Science
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• v.7
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• pp.53-63
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• 1967

In order to identify the bacteria living on the cocoons in Korea, the isolated bacterias' morphological. cultural and physiological characters has been determined through the detailed study. The second aim of this experiment was to protect against the bacteria which damage silk protein during storage. 1. The twelve strains of the bacteria were isolated and identified in the cocoons produced in Korea. The results of the identification are as the following. No 1, No 8; Bacillus subtilis variation No 2, ; Bacillus stearothermophilus No 3, ; Bacillus circulans No 5, No 6; Bacillus thuringiensis No 7, No 11; Bacillus brevis No 12, No l0; Bacillus cereus variation

• Microbiology and Biotechnology Letters
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• v.21 no.5
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• pp.453-460
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• 1993

The extracellular bacteriolytic enzyme from alkalophilic Bacillus sp. YJ-451 was endopeptidase which hydrolyzes the peptide bond at the amino group of D-glutamic acid in the peptidoglycan. Protoplast transfomation system of B. subtilis by the lytic enzyme that differs, in mechanisms, from lysozyme which was used to transformation of B. subtilis was investigated. High protoplast yield was obtained from cells cultured in PAB at the late logarithmic growth phase.

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.40-44
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• 2003

Bacillus anthracis is a gram-positive spore-forming bacterium that causes the disease anthrax. In order to develop a DNA marker specific for Bacillus anthracis and to discriminate this species from Bacillus cereus group, we applied the randomly amplified polymorphic DNA (RAPD)-PCR technique to a collection of 29 strains of the genus Bacillus, including 22 species of the B. cereus group. A 709-bp RAPD marker (KHT5) specific for B. anthracis was obtained from B. anthracis BAK. The PCR product of internal primer set from the KHT5 fragment distinguished B. anthracis from the other species of the B. cereus group.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.109-114
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• 1989

Seventeen bacterial strains producing an extracellular soybean milk clotting enzyme were Isolated from 150 soil samples, and identified as Bacillus cereus(8 strains), Bacillus pumilus(8 strains) and Bacillus licheniformis (1 strain). Among them, Bacillus pumilus strain 118 and Bacillus licheniformis strain 192 showed relatively high soybean milk clotting activity. The coagulability of enzymes from these strains decreased as the pH of soybean milk was increased from 6.0 to 7.0. The optimum temperature for soybean milk clotting activity was $65^{\circ}C$.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.1
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• pp.103-108
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• 2023

In this study, basic research was conducted to secure microbial resources applicable to autonomous crack healing concrete. To this end, in this experiment, biomineral-forming microorganisms were separated from natural sources, and the ability of survival in cement and calcium carbonate precipitation were compared to secure suitable microbial resources. Bacillus-type bacteria forming endospores were isolated from the sample, and the amount of calcium carbonate produced by the six microorganisms identified by 16S rRNA sequencing was compared. Two types of microorganisms, Bacillus velezensis and Bacillus subtilis, with the highest calcium carbonate precipitation were selected, and the survival of the microorganisms was confirmed through phase contrast microscopy after being cured after being added to the mortar. In addition, it was confirmed that the autonomous crack healing capability by the crack healing material produced by microorganisms was confirmed by artificially generating cracks in the mortar.