• Applied Biological Chemistry
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• v.40 no.1
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• pp.58-64
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• 1997

$H_2$ production by Chromatium sp., a large purple sulfur bacterium blooming in lake Kaiike, under various environmental conditions was examined. Chromatium sp. produced $H_2$ only in the presence of light and $H_2$. Maximum $H_2$ production ($0.01\;{\mu}mol/hr/(mg\;dry\;cell\;weight)$) was obtained in the solution of 20 mg $H_2S-S/l$ under low light intensity (1000 lux) at $30^{\circ}C$. $H_2$ production was severely inhibited by the presence of $N_2\;or\;NH_4^+$. The rate observed for Chromatium sp. was relatively low compared to that of other phototrophic bacteria. Chromatium sp. is probably a most potent Ha producing species in lake Kaiike, since the bacterium readily produced $H_2$ photoautotrophically even at low light intensities by the application of suboptimal $H_2$ concentrations. Based on the photoautotrophic characteristics of bacterial $H_2$ production, it is suggested that Chromatium sp. can be an economic and practical species for biological $H_2$ production system, particularly in temperate region.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.388-395
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• 2010

In order to decrease level of an organophosphorus fungicide, tolclofos-methyl, from in situ ginseng cultivating soil, we isolated a tolclofos-methyl degrading bacteria from ginseng cultivating soil samples. The bacterial strain removed tolclofos-methyl around 95% after 3 days incubation with complete liquid media. The strain was identified as Sphingomonas sp. by 16S rDNA sequence comparison, and designated as Sphingomonas sp. 224. Through the GC-MS analysis, Sphingomonas sp. 224 was proposed to have an initiative degradation pathway generating the metabolite such as 2,6-dichloro-4-methyl phenol compound from tolclofos-methyl. In addition, Sphingomonas sp. 224 was confirmed representing the effective degrading capability to tolclofosmethyl in situ soil.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.59-67
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• 2018

This study was conducted to isolate the cellulolytic bacteria able to grow on LB- Carboxymethyl cellulose (CMC) agar trypan blue medium from the mixed forest and Larix leptolepis stands. Three bacterial strains with high activity against both CMC and xylan were isolated. Both API kit test and 16S rRNA gene sequence analysis revealed that the three different isolates belong to the gene Bacillus. Therefore, the isolates named as Bacillus sp. EFL1, Bacillus sp. EFL2, and Bacillus sp. EFP3. The optimum growth temperature of Bacillus sp. EFL1, EFL2, and EFP3 were $37^{\circ}C$. The optimum temperature for CMCase and xylanase from Bacillus sp. EFL1 were $50^{\circ}C$. The optimum pH of Bacillus sp. EFL1 xylanase was pH 5.0 but the optimum pH of CMCase from Bacillus sp. EFL1 was pH 6.0. The optimum temperature of CMCase and xylanase from Bacillus sp. EFL2 was $60^{\circ}C$, respectively. The optimum pH of CMCase of Bacillus sp. EFL2 was 5.0, whereas xylanase showed high activity at pH 3.0-9.0. The optimum temperature for CMCase and xylanase of Bacillus sp. EFP3 was $50^{\circ}C$. The optimum pH for CMCase and xylanse was 5.0 and 4.0, respectively. CMCases from Bacillus sp. EFL1, EFL2, and EFP3 were thermally unstable. Although xylanase from Bacillus sp. EFL1 and EFP3 showed to be thermally unstable, xylanase from Bacillus sp. EFL2 showed to be thermally stable. Therefore, Bacillus sp. EFL2 has great potential for animal feed, biofuels, and food industry applications.

• Journal of Life Science
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• v.21 no.4
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• pp.554-560
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• 2011

This study was performed to investigate the effects of microbial augmentation on the biological treatment of paper mill wastewater. Three bacteria (KN11, KN13, KN27) capable of degrading aromatic compounds and a bacterial strain (GT21) producing an extracellular cellulase were isolated from soil and wastewater by selective enrichment culture. Through morphological, physiological, and biochemical taxonomies, isolated strains of KN11, KN13, KN27, and GT21 were identified as Acinetobacter sp., Neisseria sp., Bacillus sp., and Pseudomonas sp. and named Acinetobacter sp. KN11, Neisseria sp. KN13, Bacillus sp. KN27, and Pseudomonas sp. GT21, respectively. For analysis of non-biodegradable and chemical oxygen demand (COD)-increasing matter in a paper mill wastewater, we utilized GC/MS to detect aromatic compounds and their derivatives containing several substituted functional groups. The microbial augmentation, J30 formulated with the mixture of bacteria including Acinetobacter sp. KN11, Neisseria sp. KN13, Bacillus sp. KN27, and Pseudomonas sp. GT21, was used for the treatment of paper mill wastewater. The optimum temperature and pH for COD removal of the microbial augmentation, J30, were $30^{\circ}C$ and 7.5, respectively. For evaluation of the industrial applicability of the microbial augmentation, J30 in the pilot test, treatment efficiency was examined using paper mill wastewater. The microbial augmentation, J30, showed a COD removal rate of 87%. On the basis of the above results, we designed the wastewater treatment process of the activated sludge system.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.728-733
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• 2007

Presence and distribution of bacteria and fungi in inner compartment of PCs(Personal Computers) were investigated. Samples for the analysis were collected from inside of PCs which had been used in various facilities including public computer facilities, laboratories and computer training rooms of a university. Total number of PC examined in this study was 51 each. When the total CFU(colony forming unit) of the inner compartment of the PCs was measured, the bacterial count was found to be dependent on the operation time(total running time) of PCs. When the distribution of bacteria in the inner compartment of PCs was estimated, CPU(Central Processing Unit) cooling fan area showed the highest bacterial concentration(average 605 $CFU/cm^2$). In the case of the fungi, various opportunistic pathogens including Aspergillus sp. and Penicillium sp. were isolated and identified in the inner compartment of PCs. And the average of bacterial number in the dust collected from the PCs was 212 CFU/mg. These results indicated that handling of PC might have a risk of infection by the microorganism.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.303-309
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• 1990

To provide essential information of the role of marine bacteria on the dinoflagellate blooms, distribution of marine bacterial flora and dinoflagellate species was investigated in Chinhae Bay located in southern part of Korea from August 1989 to April 1990. Two hundred and fifty one strains of marine bacteria were isolated from seawater samples collected from the study area. Among them, Flavobacterium spp. and Acinetobacter spp. were the most dominant in bacterial flora. Another 32 strains which comprised 13 percent of total strains were Erythrobacter spp.. Based on the physiological character, Erythrobacter spp. were identified as Erythrobacter longus, Erythrobacter sp.(J-2) and Erythrobacter sp. (J-8). From the phytoplanktonic community, fourteen genera and twenty nine taxa of dinoflagellate species were identified. Based on the spatio-temporal frequence and abundance Gymnodinium sanguneum, Prorocentrum micans and Prorocentrum minimum were the aestival dominent species. However, Heterocapsa triquetra was appeared as predominant species in April. Cell density of about 2,000 cells/ml was prevailed in the bloom of August, but it developed into more intensive bloom of above 500 cells/ml in September. The water quality showed eutrophic or hypereutrophic condition, which was proved by high concentration of dissolved inorganic nitrogen, ortho-phosphate and chemical oxygen demand. Oxygen deficient water mass was found in the bottom overlying waters in August and September. High relationship between abundant bacterial flora and persistent dinoflagellate blooms in eutrophic condition would be approvable.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.368-376
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• 2009

A red pigment-producing bacterial strain was isolated from sediment sample of the East China Sea. The isolate was identified by analysis based on 16S rDNA sequence and morphological, physiological properties, biochemical characteristics and fatty acid composition. Phylogenetic analysis based on 16S rDNA sequence showed that isolate represent a phyletic lineage within the genus Zooshikella, and this strain was most closely related to Zooshikella ganghwensis KCTC $12044^T$ (AY130994) (99.79%). The strain was Gram-negative, aerobic and required NaCl at 0.5~8.0% for growth. The predominant cellular fatty acids were saturated and monounsaturated straight-chain fatty acids. Consequently, this strain was identified as a member of the genus Zooshikella and designated as Zooshikella sp. JE-34. The pigment showed characteristics similar to prodigiosin, a well-known red pigment previously detected in Serratia marcescens. The antimicrobial activity of Zooshikella sp. JE-34 bacterial pigment was tested against 18 microorganisms, which were fish and human pathogens. The Zooshikella sp. JE-34 red pigment showed high antimicrobial activity against Streptococcus iniae, S. parauberis, S. mutans, Staphylococcus aureus, and Propionibacterium acnes.

• Korean Journal of Microbiology
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• v.49 no.4
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• pp.328-335
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• 2013

As a result of conducting a cultural experiment of tomato using chicken feather protein hydrolysate (CPH) which was mass produced by keratin protein degrading bacterium Chryseobacterium sp. FBF-7 (KACC 91463P), we found that the stem and the root of tomato showed significant improvement in growth. For the purpose of phylogenic interpretation, a comparison was drawn between the effect of CPH, a treated CPH and untreated, on the changes of bacterial populations by 454 pyrosequencing based on 16S rRNA gene sequences. Tomato rhizosphere soil untreated with CPH (NCPH) showed 6.54 Shannon index from 3,281 sequence reads, and the rhizosphere soil treated with CPH (TCPH) showed 6.33 Shannon index from 2,167 sequence reads, displaying that it does not affect the diversity. Bacterial populations were composed of 19 phyla in the rhizosphere soil, and the phylum Proteobacteria occupied 40% of total bacterial populations. Bradyrhizobium, Agromonas, Nitrobacter, and Afipia (BANA group) which belong to Bradyrhizobiaceae were abundant and commonly detected in both the treated and untreated soils, suggesting the dominance of bacterial group in rhizosphere soil. The results obtained showed that CPH treatment does not affect the indigenous bacterial populations present in the rhizosphere soil.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.476-483
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• 2010

Total bacterial populations were cultured from the Hydroball cultivation media in the rhizospheres of 9 different plants including $Hedera$ $helix$ L. and $Dracaena$ $deremensis$ cv. Warneckii Compacta, etc. These cultured bacterial populations were studied to test if the bacterial populations in the plant growing pots may play a role on removal of volatile organic compounds (VOCs) such as benzene and toluene in the air. To meet this objective, first, we tested the possibility of removal of VOCs by the cultured total bacteria alone. The residual rates of benzene by the inoculation of total bacterial populations from the different plant growth media were significantly different, ranging from 0.741-1.000 of $Spathiphyllum$ $wallisii$ 'Regal', $Pachira$ $aquatica$, $Ficus$ $elastica$, $Dieffenbachia$ sp. 'Marrianne' Hort., $Chamaedorea$ $elegans$, compared to the control with residual rate of 0.596 (LSD, $P$=0.05). This trend was also similar with toluene, depending on different plants. Based on these results, we inoculated the bacterial population cultured from $P.$ $aquatica$ into the plant-growing pots of $P.$ $aquatica$, $F.$ $elastica$, and $S.$ $podophyllum$ inside the chamber followed by the VOCs injection. The inoculated bacteria had significant effect on the removal of benzene and toluene, compared to the removal efficacy by the plants without inoculation, indicating that microbes in the rhizosphere could play a significant role on the removal of VOCs along with plants.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.885-892
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• 2011

The bacterial communities in the intestinal tracts of earthworm were investigated by culture-dependent and -independent approaches. In total, 72 and 55 pure cultures were isolated from the intestinal tracts of earthworms under aerobic and anaerobic conditions, respectively. Aerobic bacteria were classified as Aeromonas (40%), Bacillus (37%), Photobacterium (10%), Pseudomonas (7%), and Shewanella (6%). Anaerobic bacteria were classified as Aeromonas (52%), Bacillus (27%), Shewanella (12%), Paenibacillus (5%), Clostridium (2%), and Cellulosimicrobium (2%). The dominant microorganisms were Aeromonas and Bacillus species under both aerobic and anaerobic conditions. In all, 39 DNA fragments were identified by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis. Aeromonas sp. was the dominant microorganism in feeds, intestinal tracts, and casts of earthworms. The DGGE band intensity of Aeromonas from feeds, intestinal tracts, and casts of earthworms was 12.8%, 14.7%, and 15.1%, respectively. The other strains identified were Bacillus, Clostridium, Enterobacter, Photobacterium, Pseudomonas, Shewanella, Streptomyces, uncultured Chloroflexi bacterium, and uncultured bacterium. These results suggest that PCR-DGGE analysis was more efficient than the culturedependent approach for the investigation of bacterial diversity and the identification of unculturable microorganisms.