• The Korean Journal of Ecology
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• v.26 no.6
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• pp.307-312
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• 2003

To study the diversity of heterotrophic bacteria isolated from intestine of starfish, Asterias amurensis, we collected starfishes from the coastal area near Jangheung-Gun, Jeollanam-Do, Korea during July, 2000. Population density and bacterial diversity in the intestine of starfish were measured. The results were as follows; The population densities of heterotrophic bacteria in the intestine of starfish were 8.65${\pm}$0.65${\times}10^3\;dfu\;g^{-1}$. Gram positive bacteria occupied 59% among 29 isolates. The community structure of dominant heterotrophic bacteria in the intestine of starfish consisted of Bacillaceae in the low G+C gram positive bacteria subphylum, Microbacteriaceae in the high G+C gram positive bacteria subphylum, and Alteromonadaceae in ${\gamma}$-Proteobacteria subphylum. Among eight strains of Bacillus spp., three strains showed more than 97% identity, but five strains showed about 90% identity with type strain on the basis of partial 16S rDNA sequence.

• Korean Journal of Microbiology
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• v.48 no.4
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• pp.270-274
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• 2012

Three actinobacterial strains exhibiting broad spectrum antibiotic activities were isolated from soil, and characterized. Through the comparative analysis of 16S rRNA genes, the three isolates could be assigned to the genus Streptomyces, as S. tanashiensis, S. nashivillensis, and S. rubiginosohelvolus were found to be the mostly related species, but the strains formed independent phylogenetic lineage. Each strain exhibited different antimicrobial profile against Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus, Gram-negative bacteria Salmonella typhi, Enterobacter cloacae, Serratia marcescens, and Pseudomonas aeruginosa, and also fungi Candida tropicalis and Candida krusei. In addition to the antimicrobial profile, the strains also differed in API ZYM test results, which implies that the three strains might produce difference antimicrobial substances.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.134-140
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• 2012

Asian dust storms originating in the arid desert of China and Mongolia usually occur from late winter through spring, and more than one million tons of dust per year is transported to the Korean Peninsula by the prevalent westerly winds. We supposed that these dust particles could include bioaerosols and act as carriers of microorganisms. In order to clarify the dynamics of microorganisms moving with these particles, the concentration and composition of microorganisms associated with settled particles were compared between samples collected during Asian dust events and those under non-dust periods. From February to April 2008, settled dust particles were collected at one location in Ulsan using rainfall meter of 200 mm diameter. During this period, there was one Asian dust event in Ulsan. The bacterial concentrations were higher in samples collected during Asian dust event than those under non-dust period, whereas fungal concentrations were rather similar regardless of the Asian dust event. We analyzed 16S rRNA gene sequences of 45 bacterial isolates obtained from the settled particle samples. These isolates belonged to either genus Bacillus or genus Streptococcus and were tentatively identified as B. amyloliquefaciens, B. aryabhattai, B. atrophaeus, B. licheniformis, B. megaterium, B. methylotrophicus, B. pumilus, B. sonorensis, B. subtlis, B. vallismortis, S. epidermidis, and S. succinus. In cases of fungal isolates, genera such as Mucor, Alternaria, Cladosporium, and Aspergillus were tentatively identified from samples collected at both Asian dust and non-Asian dust periods. It appears that endospore-forming bacteria such as Bacillus sp. rather than fungal spores are more likely to be associated with Asian dust particles.

• Research in Plant Disease
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• v.10 no.4
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• pp.331-336
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• 2004

The fungus genus Sclerotinia contains a number of important plant pathogens. Vegetable growers in our country are probably most familiar with Sclerotinia sclerotiorum, the causes of sclerotinia rot on crisphead lettuce. S. sclerotiorum has a wide host range which can include lettuce as well as crops such as broccoli, cabbage, carrots, celery, beans, peppers, potatoes, stocks, and tomato. Some fungicides, including benomyl, are effective in some crops, but not all. So, we isolated a antagonistic bacteria that are active on sclerotinia rot caused by S. sclerotiorum and that can be used to control it. About 702 strains had been isolated from soil around plant roots in the field. Ten strains showed strong antifungal activity against S. sclerotiorum. In pot test for antagonistic activity, A-7 strain showed high control value against the pathogen when compared with others. The strain was, therefore, selected as a biocontrol candidate against sclerotinia rot and its biochemical properties and 16S rDNA sequence was analyzed. The A-7 strain was highly related to Bacillus subtilis and B. amyloliquefaciens. To confirm precise identification, we had performed gyr A gene sequences analysis. Its sequence had 96% similarity with B. amyloliquefaciens. Consequently, the isolate was identified as B. amyloliquefaciens A-7.

• Journal of Ginseng Research
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• v.40 no.2
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• pp.97-104
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• 2016

Background: Rhizobacteria play an important role in plant defense and could be promising sources of biocontrol agents. This study aimed to screen antagonistic bacteria and develop a biocontrol system for root rot complex of Panax notoginseng. Methods: Pure-culture methods were used to isolate bacteria from the rhizosphere soil of notoginseng plants. The identification of isolates was based on the analysis of 16S ribosomal RNA (rRNA) sequences. Results: A total of 279 bacteria were obtained from rhizosphere soils of healthy and root-rot notoginseng plants, and uncultivated soil. Among all the isolates, 88 showed antagonistic activity to at least one of three phytopathogenic fungi, Fusarium oxysporum, Fusarium solani, and Phoma herbarum mainly causing root rot disease of P. notoginseng. Based on the 16S rRNA sequencing, the antagonistic bacteria were characterized into four clusters, Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetesi. The genus Bacillus was the most frequently isolated, and Bacillus siamensis (Hs02), Bacillus atrophaeus (Hs09) showed strong antagonistic activity to the three pathogens. The distribution pattern differed in soil types, genera Achromobacter, Acidovorax, Brevibacterium, Brevundimonas, Flavimonas, and Streptomyces were only found in rhizosphere of healthy plants, while Delftia, Leclercia, Brevibacillus, Microbacterium, Pantoea, Rhizobium, and Stenotrophomonas only exist in soil of diseased plant, and Acinetobacter only exist in uncultivated soil. Conclusion: The results suggest that diverse bacteria exist in the P. notoginseng rhizosphere soil, with differences in community in the same field, and antagonistic isolates may be good potential biological control agent for the notoginseng root-rot diseases caused by F. oxysporum, Fusarium solani, and Panax herbarum.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.1
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• pp.113-118
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• 2009

We investigated the structure of bacterial communities present in livestock manure-based composting processes and evaluated the bacterial succession during the composting processes. Compost samples were derived separately from swine manure, dairy manure and sewage sludge. The structure of the bacterial community was analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) using universal eubacterial primers. The genus Bacillus and related genera were mainly detected following the thermophilic composting phase of swine and dairy manure composts, and the members of the phylum Bacteroidetes were mainly detected in the cattle manure waste-based and sewage sludge compost. We recovered and sequenced limited number of the bands; however, the PCR-DGGE analysis showed that predominant diversities during the composting processes were markedly changed. Although PCR-DGGE analysis revealed the presence of different phyla in the early stages of composting, the members of the phylum Firmicutes and Bacteroidetes were observed to be one of the predominant phyla after the thermophilic phase.

• Microbiology and Biotechnology Letters
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• v.24 no.3
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• pp.344-351
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• 1996

Microorganisms growing alcoholic distillery wastes were isolated from soil. Of them, the selected strain EL-9 had a capability of accumulating poly-$\beta$-hydroxybutyrate (PHB) when grown in alcoholic distillery wastes. The strain EL-9 was identified as a genus Actinobacillus based on the morphological, cultural, and biochemical characteristics. The strain EL-9 was named temporarily as Actino- bacillus sp. EL-9. The optimal temperature and pH for cell growth of Actinobacillus sp. EL-9 were 30$\circ$C and 7.0, respectively. The optimal medium compositions for cell growth comprised glucose 2%, NH$_{4}$NO$_{3}$ 0.15%, Na$_{2}$HP0$_{4}$-12H$_{2}$O 0.25%, KH$_{2}$PO$_{4}$ 0.25%, MgSO$_{4}$4-7H$_{2}$O 0.15%, FeSO$_{4}$-7H$_{2}$O 0.005%, CaCl$_{2}$-2H$_{2}$O 0.003% and trace element solution 5m/l. To investigate the optimal conditions for PHB production, two-stage culture technique was used. The result showed that the optimal conditions for PHB production are identical those for cell growth. When propionic acid was added as a cosubstrate, PHB/HV copolymer was produced.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.973-979
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• 1994

Microorganisms, including the strain IJ-3 isolated from soil, were found to secrete an extracellular soybean protein coagulating enzyme and the strain, IJ-3 was identified as Genus Bacillus according to the Bergey's manual . The enzyme coagulated protein in soymilk , thus forming a curd at pHs 5.8-6.4 and at 55-75℃. The optimum temperature for soybean protein coagulating activity was 65-75℃ and the enzyme was stable at temperature below 50℃ and was found to be stable with about 60-100% of the original activity at a with pH ranges(pH6-7). The molecular weight of enzyme was estimated to be 28,000 by SDS-PAGE. The curd formed with the enzyme from Bacilus sp. IJ-3 has a smooth texture, and a mild taste without any bitterness or a beany flavor.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.469-474
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• 2001

The actinomycete strain AMLK-335 was antagonistic to vancomycin-resistant enterococci (VRE). Based on the diaminopimelic acid (DAP) type, and morphological and physiological characteristics revealed by scanning electron microscopy (SEM), AMLK-335 was confirmed to belong to the genus Streptomyces. Analysis of the 16S rDNA nucleotide sequences found AMLK-335 to have a relationship with Streptomyces platensis. The production of antibiotic from this strain was most favorable when cultured on glucose, polypeptone, yeast extract (PY) medium for 6 days at $27^{\circ}$. The antibiotic was identified as cyclo(L-phenylalanyl-L-prolyl) by comparing ti with the reported MS and NMR spectral data. Cyclo(phe-pro) from the PY cultures of AMLK-335 was most effective (K-98-258). Futhermore, cyclo(phe-pro) had antimicrobial activity against Bacillus subtilis, Microcuccs luteus, Staphylococcus aureus, and Saccharomyces cerevisiae, but it wa ineffective against Candida albicans, Streptomyces murinus, and Aspergillus niger.

• Archives of Pharmacal Research
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• v.27 no.11
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• pp.1147-1153
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• 2004

Bladder cancer is a common cancer with high risk of recurrence and mortality. Intravesicle chemotherapy after trans-urethral resection is required to prevent tumor recurrence and progression. It has been known that antioxidants enhance the antitumor effect of bacillus Calmette-Guerin (BCG), the most effective intravesical bladder cancer treatment. Capsaicin, the major pungent ingredient in genus Capsicum, has recently been tried as an intravesical drug for overactive bladder and it has also been shown to induce apoptotic cell death in many cancer cells. In this study, we investigated the apoptosis-inducing effect and alterations in the cellular redox state of capsaicin in MBT-2 murine bladder tumor cells. Capsaicin induced apoptotic MBT-2 cell death in a time- and dose-dependent manner. The capsaicin-induced apoptosis was blocked by the pretreatment with Z-VAD-fmk, a broad-range caspase inhibitor, or Ac-DEVD-CHO, a caspase-3 inhibitor. In addition to the caspase-3 activation, capsaicin also induced cytochrome c release and decrease in Bcl-2 protein expression with no changes in the level of Bax. Furthermore, capsaicin at the concentration of inducing apoptosis also markedly reduced the level of reactive oxygen species and lipid peroxidation, implying that capsaicin may enhance the antitumor effect of BCG in bladder cancer treatment. These results further suggest that capsaicin may be a valuable intravesical chemotherapeutic agent for bladder cancers.