• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.285-290
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• 1998

Thermophilic Bacillus species was studied as a microbial indicator to pursue the compost a application history. Thermophilic Bacillus species could be easily determined by the plate culture method within 12 hours in $65^{\circ}C$ incubator. The density of thermophilic Bacillus species in soils was gradually increased with the application rate of rice straw compost, and correlated to the soil organic matter content in $R^2=0.835^{**}$(n=32) coefficient on the 43-year-long term rice paddy fields.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.294-298
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• 1998

The effect of gamma irradiation on the survival of spore bacteria was investigated in frozen cells ($-18^{\circ}C$) with 0.1 M phosphate buffer and inoculated cells in beef. In the case of the frozen cells at log phase, the radiation $D_{10}\;and\;12D_{10}$ values were 0.29 kGy and 3.48 kGy in Bacillus subtilis, 0.39 kGy and 4.68 kGy in Bacillus cereus and 0.46 kGy and 5.52 kGy in Clostridium perfrigens. And inactivation factors were 6.52~10.34 and 10.87~17.24 at the dosage of 3 kGy and 5 kGy, respectively. The radiosensitivity of inoculated cells in beef showed the $D_{10}$ value of 0.59~0.76 kGy, the $12D_{10}$ value of 7.08~9.12 kGy, and inactivation factors of 3.95~8.47. The radiosensitivity of the frozen cells was higher than that of inoculated cells in beef.

• Research in Plant Disease
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• v.12 no.2
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• pp.81-84
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• 2006

Trichoderma harzianum 23 WP and Bacillus subtilis 122 WP were formulated as antagonists of Sclerotium cepivorum and Sclerotium sp. of garlic white rot. In the field test, applications of Trichoderma harzianum WP and Bacillus subtilis WP reduced garlic white rot by Sclerotium cepivrum from 10.9% in the control to 4.1% and 6.2%, respectively at Taean. Also at Seosan, applications of Trichoderma harzianum 23 WP and Bacillus subtilis 122 WP reduced garlic white rot by Sclerotium sp. from 17.8% in the control to 1.2% and 2.6%, respectively. Treatment of Trichoderma harzianum 23 WP and Bacillus subtilis 122 WP increased garlic yield in two area. Therefore, Trichoderma harzianum 23 WP and Bacillus subtilis 122 WP have shown potential as biofungicides of garlic white rot in the two different pathogens.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.309-313
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• 1997

Maillard reaction products (MRPs) added into a culture and the resultant bacterial growth were investigated using response surface methodology. The coefficients of determination $(R^{2})$ of response surface regression equations for bacteria were 0.9544 and 0.9578 in Bacillus subtilis and Bacillus natto, respectively. The MRPs produced at higher reaction temperature and for longer reaction time showed greater antimicrobial effect for Bacillus subtilis. Especially, the MRPs produced at temperature above $150^{\circ}C$ for 8 to 12 hrs showed the strongest antimicrobial effect. The MRPs produced at lower reaction temperature and for shorter reaction time showed greater microbial growth effect for Bacillus natto, but those produced at the reaction temperature higher than $160^{\circ}C$ showed the greatest antimicrobial effect. In the ridge analysis, the growth of Bacillus subtilis was the most significantly inhibited in the presence of MRPs prepared at $159.10^{\circ}C$ and pH 12.21 for 9.67 hrs, and the growth of Bacillus natto was the most significantly inhibited in the presence of MRPs prepared at $169.94^{\circ}C$ and pH 9.66 for 9.22 hrs.

• Journal of Species Research
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• v.7 no.3
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• pp.202-209
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• 2018

Eight bacterial strains, 18JY8-13, 18JY13-16, 18JY43-7, 18JY12-7, 18JY1-1, 18JY1-7, 18JY15-3, and 18JY7-2 assigned to the phylum Firmicutes were isolated from a variety of soil samples collected in the Jeju Island, Korea. Cells of the eight strains were Gram-positive, aerobic and showed resistant to UV-radiation. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strains 18JY8-13, 18JY13-16, 18JY43-7, 18JY12-7, 18JY1-1, 18JY1-7, 18JY15-3, and 18JY7-2 were most closely related to Bacillus paranthracis(99.9%), Bacillus paramycoides(99.6%), Bacillus australimaris(99.9%), Bacillus wiedmannii (100%), Bacillus halosaccharovorans(99.6%), Bacillus deserti(98.7%), Bacillus cereus (99.8%), and Bacillus albus(100%), respectively. This is the first report of these eight species in Korea.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.7-13
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• 1992

A moderately thermophilic, alkalophlic and powerful crystalline cellulose-digesting bacterium, Bacillus K-12, was isolated from filter paper wastes and found to be similar to Bacillus circulans or Bacillus pumilis, except for its ability to grow at a moderately high pH and temperature. The isolate grew at a pH ranging from 6 to 10 and at a temperature ranging from 35 to $65^{\circ}C$ and produced a large amount of cellulase components containing avicelase, xylanase, CMCase, and FPase when grown in avicel medium for 5 to 7 days at $50^{\circ}C$. The crude enzyme preparation from the culture broth hydrolyzed xylan, raw starch, pullulan and ${\beta}-1,3$ glucan such as laminarin. Furthermore, the enzyme hydrolyzed crystalline cellulose to cellobiose and glucose and had a broad pH activity curve (pH 6~9). The enzyme was stable up to $70^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.349-354
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• 1991

An alkaline amylase-producing Bacillus sp. GM8901 was isolated and some properties of crude enzyme extract were examined. The microbiological and biochemical characteristics of GM8901 were very similar to those of B. licheniformis. The optimal temperature and pH for the cell growth and amylase production were $50^{\circ}C$ and pH 10.5. The crude amylase extract showed that the optimal temperature and pH were $50{\sim}60^{\circ}C\;and\;pH\;10{\sim}12$, respectively, and that the activity of amylase was stable up to $50^{\circ}C$ and in the range of $pH\;3{\sim}12$.

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.186-189
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• 2012

A gene coding for mannanase (manA) from Bacillus subtilis was introduced into a shuttle vector pGK12 between Escherichia coli, B. subtilis and Lactobacillus paracasei. As a result of transferring the resultant plasmid, designated pGK12M3, into three different strains, the manA gene was found to be expressed in L. paracasei as well as in B. subtilis and E. coli. In a 4 L fermentor culture, the production of mannanase by recombinant L. paracasei (pGK12M3) reached a maximum level of 5.4 units/ml in an MRS medium with a fixed pH 6.5. Based on the zymogram of mannanase, it is assumed that mannanase produced by recombinant L. paracasei is not maintained stably with proteolytic degradation. The optimal temperature and thermostability of mannanase produced by recombinant L. paracasei were also found to be different from those of enzymes produced by B. subtilis.

• The Korean Journal of Mycology
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• v.41 no.2
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• pp.112-117
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• 2013

Phytophthora capsici is one of major limiting factors in production of pepper and other important crops worldwide by causing foliage blight and rot on fruit and root. Increased demand for the replacement of fungicides has led to searching a promising strategy to control the fungal diseases. To meet eco-friendly agriculture practice, we isolated microorganisms and assessed their beneficial effects on plant health and disease control efficacy. A total of 360 bacterial strains were isolated from rhizosphere soil of healthy pepper plants, and categorized to 5 representative isolates based on colony morphology. Among the 5 bacterial strains (GJ-1, GJ-4, GJ-5, GJ-11, GJ-12), three bacterial strains (GJ-1, GJ-11, GJ-12) presented antifungal activity against P. capsici in an fungal inhibition assay. In phosphate solubilization and siderophore production, the strain GJ-1 was more effective than others. The strain GJ-1 was identified as Bacillus sp. using 16S rDNA analysis. Bacillus sp. GJ-1 was also found to be effective in inhibiting other plant pathogenic fungi, including Rhizoctonia solani, Pythium ultimum and Fusarium solani. Therefore, the Bacillus sp. GJ-1 can serve as a biological control agent against fungal plant pathogens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.1035-1040
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• 2016

This study investigated the prevalence of foodborne pathogens and the bacterial community of traditional Doenjang collected from a longevity area in Korea as well as the antagonistic effect of traditional Doenjang isolates against Bacillus cereus to estimate the microbiological safety of traditional Doenjang. Aerobic bacteria showed $10^6{\sim}10^9CFU/g$, whereas coliform bacteria was not detected. Foodborne pathogens were not detected except B. cereus, which was detected in seven samples out of 10 Doenjang samples. A total of 327 isolates were identified from traditional Doenjang. The isolates consisted of Bacillus subtilis 155 (47.4%), Bacillus licheniformis 68 (20.8%), Bacillus amyloliquefaciens 46 (14.1%), and Bacillus pumilus 18 (5.5%). Antagonistic effect against B. cereus was detected in 20 (6.1%) of 327 isolates, which consisted of B. subtilis (12 strains), B. amyloliquefaciens (5 strains), and B. licheniformis (3 strains). The inhibitory zone for the antagonistic effect was 9.0~12.0 mm in diameter. Although a small amount of traditional Doenjang was tested in this study, these results indicated that the potential risk of B. cereus in traditional Doenjang is lower than generally presumed. It is necessary to monitor the antagonistic effect of traditional Doenjang isolates against B. cereus.