• Korean Journal of Microbiology
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• v.54 no.4
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• pp.398-409
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• 2018

In the present study, biogenic amine-forming Bacillus spp. and bacteriocin-producing lactic acid bacteria (LAB) isolated from Doenjang were generally identified through 16S rRNA gene sequencing, and the physicochemical and microbiological characteristics of cheonggukjang prepared using the isolated strains were investigated. Biogenic amine-producing bacteria from the samples were identified as Bacillus licheniformis DB102, B. subtilis DB203, B. stearothermophilus DB206, B. pumilus DB209, B. subtilis DB310, B. coagulans DB311, B. cereus DB313, B. amyloliquefaciens DB714, B. amylolique-faciens DB915, B. licheniformis DB917, B. cereus DB1019, B. subtilis DB1020, B. megaterium DB1022. The bacteriocin-producing LAB showed antibacterial effect against biogenic amine-producing Bacillus spp. were identified as Lactobacillus plantarum DLA205, L. brevis DLA501, L. fermentum DLA509, L. acidophilus DLA703, and Enterococcus faecalis DLA804. The bacteriocin produced by the LAB significantly decreased the viable numbers and the amine production ability of the biogenic amine-forming Bacillus spp. in a concentration dependent manner. Therefore, the pH, ammonia nitrogen and biogenic amine content of cheonggukjang prepared by mixed culture of the LAB and Bacillus spp. were significantly decreased compared to the control group.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.175-179
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• 2006

This study was carried out to investigate the change of rhizosphere microflora in paddy soils of long-term application of same fertilizer by single cropping. Treatments consisted of no fertilizer, NPK, PK, NK, NP and NPK + compost and the same fertilizer has been applied to the soil of each treatment for thirty five years. Any remarkable difference of the microbial population structure was not detected from the rhizosphere of Hwayeongbyeo and that of Hwasambyeo. However, slight difference of dominant microbial species in the rhizosphere was recognized between different fertilization practice. The bacterial population in the rhizosphere was steadily reduced over time after rice plant setting out, while actinomycetal population was increased over time. The increase of actinomycetal population was the highest in the NPK + compost treatment, suggesting the effect of organic matters in the change of actinomycetal population. As for the aerobic culturable bacterial diversity, Bacillus megaterium, B. mycoides, B. licheniformis and B. subtilis were dominants in genus Bacillus, and Streptomyces spororaveus, S. canus, S. tauricus and S. galbus in genus Streptomyces and genus Micromonospora was another dominant in actinomycetes.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.1
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• pp.37-40
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• 2003

The antibacterial action of violet pigment, a mixture of violacein and deoxyviolacein, isolated from phychrotrophic bacterium RT102 strain was examined, and the operational conditions for the effective production of violet pigment were studied. The antibacterial activity of the violet pigment was confirmed for several bacteria such as Bacillus licheniformis, Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, and Pseudomonas aeruginosa, and the high concentration of violet pigment, above about 15mg/L, caused not only growth inhibition but also death of cells. The growth properties of RT102 strain were clarified under various incubation conditions such as pH, temperature, and dissolved oxygen concentration. The maximum violet pigment concentration, i.e. 3.7 g/L, and the maximum productivity of violet pigment, i.e. 0.12 g .L$\^$-1/H$\^$-1/, were obtained in a batch culture of pH 6, 20$^{\circ}C$, and 1 mg/L of dissolved oxygen concentration.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.989-992
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• 2007

Twenty bacterial strains were isolated and identified from human scalps. These strains were identified as 14 Bacillus megaterium, 1 Bacillus subtilis, 3 Staphylococcus aureus and 2 Staphylococcus saprophyticus. Two genuses are Gram-positive. In order to search for antimicrobial substances from natural plants, eighteen plant materials being made of perilla leaf as well as spices including garlic and ginger were used. The effects of these vegetable and fruit juices on the growth of scalp bacterial strains were investigated. Garlic and lemon juices showed antimicrobial activities on the growth of twenty bacterial strains belonging to 4 kinds of species. Onion, spring onion and leek juices inhibited the growth of only one bacterial strains Bacillus megeterium MS13.

• Research in Plant Disease
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• v.19 no.1
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• pp.12-20
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• 2013

To isolate antagonistic bacteria against sclerotinia rot of lettuce, caused by Sclerotinia sclerotiorum, soil samples were collected from the diseased greenhouse field in Namyangju city, Gyeong-gi province from 2007 to 2008. A total of 196 bacterial isolates were isolated using serial dilution method. In dual culture assay in vitro, 26 isolates showed more than 80% of inhibition rates of mycelial growth of S. sclerotiorum. Based on 16S rDNA sequence analysis, the 26 isolates were identified as Bacillus megaterium, B. cereus, B. subtilis, Arthrobacter nicotianae, A. ramosus, Pseudomonas filiscindens, Stenotrophomonas maltophilia, Brevibacterium frigoritolerans and Sphingobacterium faecium. The 26 isolates inhibited the mycelial growth of S. sclerotiorum up to 80% and the sclerotial germination 0-100%. In the greenhouse pot test of ten isolates conducted in summer, 2 isolates B. megaterium (DK6) and B. cereus (C210) showed control efficacy on sclerotia viability of S. sclerotiorum, 20% and 35%, respectively. In the greenhouse pot test in winter, the disease incidence of the control group was 80%, whereas those of 9 isolates among 26 were approximately 20%. From the result, the 9 isolates are expected as potentially antagonistic bacteria for biological control of sclerotinia rot of lettuce caused by S. sclerotiorum.

• Journal of Microbiology and Biotechnology
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• v.1 no.2
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• pp.102-110
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• 1991

Alkalophilic Bacillus sp. YJ-451, which was isolated from soil at several area in Korea, produced a novel type of bacteriolytic enzyme (cell wall peptidoglycan hydrolase) extracellulary. The cell wall hydrolytic activity was identified as a clear zone on sodium dodecyl sulfate polyacrylamide gel electrophoresis containing 0.2% (w/v) cell wall of Bacillus sp. as substrate. This enzyme was successively purified 66 fold with 3.2% yield in culture broth by ammonium sulfate precipitation, CM-cellulose column chromatography, and gel filtration, followed by hydroxylapatite column chromatography. The molecular weight of the purified enzyme was estimated to be 27,000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum pH and temperature for the activity of the enzyme were pH 10.0 and $50^{\circ}C$, respectively. The enzyme was stable between pH 5.0 and 10.0 and up to $40^{\circ}C$. Among the microorganisms used in this experiment the enzyme was active against most of gram negative strains and the genus Bacillus such as B. megaterium, B. licheniformis, B. circulans, B. pumilus, B. macerans, B. polymyxa. The release of dinitrophenylglutamic acid but not reducing group from cell wall peptidoglycan digested by the enzyme suggested that the enzyme is a kind of peptidase which hydrolyzes the peptide bond at the amino group of D-glutamic acid in the peptidoglycan.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.614-622
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• 2013

Daqu, a traditional fermentation starter, has been used to produce attractively flavored foods such as vinegar and Chinese liquor for thousands of years. Although Bacillus spp. are one of the dominant microorganisms in Daqu, more precise information is needed to reveal why and how Bacillus became dominant in Daqu, and next, to assess the impact of Bacillus sp. on Daqu and its derived products. We combined culture-dependent and culture-independent methods to study the ecology of Bacillus during Daqu incubation. Throughout the incubation, 67 presumptive Bacillus spp. isolates were obtained, 52 of which were confirmed by 16S rDNA sequencing. The identified organisms belonged to 8 Bacillus species: B. licheniformis, B. subtilis, B. amyloliquefaciens, B. cereus, B. circulans, B. megaterium, B. pumilus, and B. anthracis. A primer set specific for Bacillus and related genera was used in a selective PCR study, followed by a nested DGGE PCR targeting the V9 region of the 16S rDNA. Species identified from the PCR-DGGE fingerprints were related to B. licheniformis, B. subtilis, B. amyloliquefaciens, B. pumilus, B. benzoevorans, and B. foraminis. The predominant species was found to be B. licheniformis. Certain B. licheniformis strains exhibited potent antimicrobial activities. The greatest species diversity occurred at the Liangmei stage of Daqu incubation. To date, we lack sufficient knowledge of Bacillus distribution in Daqu. Elucidating the ecology of Bacillus during Daqu incubation would enable the impact of Bacillus on Daqu to be accessed, and the quality and stabilization of Daqu-derived products to be optimized.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.707-714
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• 2013

Microbially induced calcium carbonate precipitation (MICCP) is a naturally occurring biological process that has various applications in remediation and restoration of a range of building materials. In the present investigation, five ureolytic bacterial isolates capable of inducing calcium carbonate precipitation were isolated from calcareous soils on the basis of production of urease, carbonic anhydrase, extrapolymeric substances, and biofilm. Bacterial isolates were identified as Bacillus megaterium, B. cereus, B. thuringiensis, B. subtilis, and Lysinibacillus fusiformis based on 16S rRNA analysis. The calcium carbonate polymorphs produced by various bacterial isolates were analyzed by scanning electron microscopy, confocal laser scanning microscopy, X ray diffraction, and Fourier transmission infra red spectroscopy. A strain-specific precipitation of calcium carbonate forms was observed from different bacterial isolates. Based on the type of polymorph precipitated, the technology of MICCP can be applied for remediation of various building materials.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.2
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• pp.30-36
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• 2001

The microbiodeterioration of paper material like books, archival material, manuscripts both illustrated and written, decorative wall papers, etc. is a serious problem throughout the world in museums, libraries, archives, etc. where these materials are placed. The major ecological fungi from record materials of library with ancient achieves were isolated and identified as Aspergillus niger, Aspergillus oryzae, Neurospora sitophile. Mucor mucedo, Mucor rouxii, Penicillium notatum, Rhizopus delema, Rhizopus nigracans, Thanmnidium elegans, Tricodema viridae, Bacillus cereus. Bacillus megaterium, Enterrobacter aerogenes, and Staphylococcus auerus. This study was carried out to investigate the antigungal activities of essential oils. The Essential oils from herb were obtained by vapor distillation method, and the antimicrobial activities were examined with ten fungi & four bacteria. It was found to have activity against microorganisms isolated from a achieves stack rooms.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.11
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• pp.812-820
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• 2011

This study was conducted to characterize $CO_2$ biomineralization on several minerals (i.e., CaO, MgO, $SiO_2$) by bottle test in an aqueous solution and solidified sludge using different aerobic bacterial strains like Bacillus megaterium and Bacillus pasteurii by batch test. These bacteria promote the formation of microenvironments that facilitate the precipitation of mineral phases that were unsaturated in the bulk solution. For one type of mineral solely amended, the $CO_2$ was reduced at the highest of 4.0 mmol for MgO while it was not that much lower for CaO and $SiO_2$ showing 1.1 and 0.3 mmol $CO_2$2, respectively. For two types of minerals simultaneously amended, the $CO_2$ was reduced at the greater extent for both Ca + Mg and Mg + Si showing 2.7 and 2.3 mmol, respectively whereas it was less for Ca + Si at 1.8 mmol. For solidified sludge, the $CO_2$ reduction rate changed depending on the volume of solidified sludge placed in the medium and the input $CO_2$ concentration.. The reduction rate of $CO_2$ was increased with increasing the volume of solidified sludge. Results of XRD analysis indicate that $CaCO_3$ (Calcite) was dominantly formed among others (e.g., Aragonite, Dolomite). SEM analysis showed that the sample with Bacillus pasteurii, could more form minerals rather than control. As demonstrated in this study, $CO_2$ would be effectively sequestered in biomineralization process.