• Korean Chemical Engineering Research
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• v.53 no.4
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• pp.524-529
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• 2015

This study was conducted to optimize the medium composition for cold-adaptive protease production of Enterobacteriaceae sp. by response surface methodology (RSM). Yeast extract, and TritonX-100 were identified as the significant factors affecting protease from one-factor-at-a-time method. RSM studies for optimizing protease production of Enterobacteriaceae sp. have been carried out for three parameters including yeast extract concentration, TritonX-100 concentration, and culture pH. These significant factors were optimized as 6.690 g/L yeast extract, 0.018 g/L Triton$^{TM}$ X-10, and pH 6.677. The experimentally obtained protease activity was 8.03 U /L, and it became 1.5-fold increase before optimization.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.100-107
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• 2013

Unlike general microwave, QRD (Quadratic Residue Diffusor) Microwave used in this study is known as a new technology that enhances the sterilization effect with low power because it is possible to induce the average sterilization by changing wavelength phase difference. Therefore, basic research was conducted on the function that could sterilize culture media for plant factory by using environmentally friendly and low energy consuming QRD Microwave. The results are as follows: It was confirmed that there was no external deformation in the polyurethane foam and rock wool medium when changing the microwave level between 2 and 8 kW in different water content of culture media. However, PDA solid media at 2 kW were not dissolved in 60 and 180 seconds. All of the media were dissolved in other processing. There was little difference in the microwave irradiation level and surface temperature of the strain according to the processing time between Bacillus sp. and Burkholderia sp. In the sterility test according to the microwave irradiation level and processing time, it was confirmed that both Bacillus sp. and Burkholderia sp. grew in the microwave level 2 kW regardless of time. In the microwave level 6 kW, all experimental groups except the processing of Burkholderia sp. for 60 seconds were sterilized, and all of Bacillus sp. was killed in the all experimental groups. In the microwave level 8 kW, it was confirmed that both Bacillus sp. and Burkholderia sp. were sterilized regardless of time. The temperature in microwave-processed media after contaminating strains to each medium was maintained at more than 100 in polyurethane foam and rock wool medium after 60 seconds. In general, it was shown that it was possible to sterilize after 60 seconds. Therefore, it is considered that Bacillus sp. and Burkholderia sp. which are the biggest problems in the plant factory can be adequately sterilized by QRD Microwave used in this study.

• Korean Journal of Microbiology
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• v.51 no.1
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• pp.31-38
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• 2015

The bacterial community structures of two marine sponges, Cinachyrella sp. and Plakortis sp., collected from Chuuk in the South Pacific in February 2012 were analyzed by PCR-DGGE (Denaturing Gradient Gel Electrophoresis) fingerprinting. After isolation of the total genomic DNAs from the sponges, the V3 regions of the 16S rRNA genes were amplified and subjected to DGGE profiling. The two species of sponges displayed different DGGE band patterns. The sequences derived from the DGGE bands revealed 85-100% similarities to known bacterial species in the public database. The bacterial community of Cinachyrella sp. was composed of 6 classes: Actinobacteria, Bacteroidetes, Chloroflexi, and Proteobacteria (Alpha-, Gamma-, Delta-). The bacterial community of Plakortis sp. included 7 classes: Actinobacteria, Chloroflexi, Firmicutes, Spirochaetes, and Proteobacteria (Alpha-, Gamma-, Delta-). Though Actinobacteria, Chloroflexi and Proteobacteria were commonly found in both sponges, the predominant bacterial communities differed between the two. Namely, the predominant bacterial groups in Cinachyrella sp. and Plakortis sp. were Proteobacteria and Chloroflexi, respectively. The sponge-associated bacteria are sponge host-specific, as each of the tested sponges from the same geographical location had different predominant bacterial diversity.

• BMB Reports
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• v.33 no.4
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• pp.332-336
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• 2000

Phenazine 1-carboxylic acid (PCA) is an antifungal antibiotic isolated from a culture filtrate of Bacillus sp. B-6 producing an acyl CoA synthetase inhibitor. This antibiotic is reported as an inhibitor of an acyl CoA synthetase from Pseudomonas sp.. Bacillus sp. B-6 was resistant to PCA up to 350 ${\mu}g/ml$. We investigated the mechanism of the resistance of Bacillus sp. B-6 to PCA. The rate of growth in a medium containing up to 100 ${\mu}g/ml$ was as rapid as the PCA-free medium. At a PCA concentration of 300 ${\mu}g/ml$, the growth rate was more than half that of the control. In this work, we purified acyl CoA synthetase from Bacillus sp. B-6 and found that this acyl CoA synthetase was much less sensitive to PCA than the acyl CoA synthetase from other source. These findings suggested that the insensitivity of Bacillus sp. B-6 acyl CoA synthetase plays an important role in the PCA resistance of this bacterium.

• Journal of the Korean institute of surface engineering
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• v.5 no.1
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• pp.8-10
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• 1972

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.1-7
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• 2003

The aim of this work was to investigate the characterization and sequence of catechol 2,3-dioxygenase isolated from Delfia sp. JK-2, which could utilize aniline as sole carbon, nitrogen and energy source. In initial experiments, several characteristics of C2,3O separated with ammonium sulfate precipitation, DEAE-sepharose were investigated. Specific activity of C2,3O was approximately 4.72 unit/mg. C2,3O demonstrated its enzyme activity to other substrates, catechol and 4-methylcatechol. The optimum temperature of C2,3O was $$Cu^{2+}$^{\circ}C$, and the optimal pH was approximately 8. Metal ions such as $Ag^{+}$, $Hg^{+}$, and $Cu^{2+}$ showed inhibitory effect on the activity of C2,3O. Molecular weight of the enzyme was determined to approximately 35 kDa by SDS-PAGE. N-terminal amino acid sequence of C2,3O was analyzed as $^{1}MGVMRIG-HASLKVMDMDA- AVRHYENV^{26}$, and exhibited high sequence homology with that of C2,30 from Pseudomonas sp. AW-2, Comamonas sp. JS765, Comamonas testosteroni and Burkholderia sp. RPO07. PCR product was amplified with the primers derived from N-terminal amino acid sequence. In this work, we found that the amino acid sequence of Delftia sp. JK-2 showed high sequence homology of C2,3O from Pseudomonas sp. AW-2 (100%) and Comamonas sp. JS765 (97%).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.401-411
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• 1995

Flavobacterium spp., Pseudomonas spp., and Vibrio spp. were isolated from samples(sediments) of Sagami Bay and Suruga Bay(in Japan) at 810-4,000m in depth. Among isolated strains, Vibvio sp.-86 and sp.-87 strains were identified as barophilic and psychrophilic ones. They grew in 400 atm and showed best growth at 100 atm. Marine bacteria grown at 400 atm were long rod shape and 30 to 50times longer than those grown at 1 atm. which were short rod shape and formed flocks (aggregates). Vibrio sp,-86 strain grew at $5-37^{\circ}C\;and\;0,5-9.0\%\;NaCl\;(3.0\%\;of\;optimum\;concentration),$ while Vibrio sp.-87 strain grew at $1-7\%\;NaCl\;(2,0\%\;of\;optimum\;concentration).$ The fatty acid compositions of Vibrio sp.-86 strain grown at 1 atm were $C_{20}-C_{22:0},\;C_{l6:1},\;and\;C_{16:0}$ in the order of their abundance and at 400 atm the order were $C_{18:1},\;C_{18:0},\;and\;C_{20}-C_{22}$, whereas those of Vibrio sp.-87 strain at 1 atm were $C_{6:1},\;C_{14:1},\;and\;C_{20}-C_{22}$ and at 400 atm the order were $C_{14:1},\;C_{12:0},\;and\;C_{16:1}$ The amino acids compositon of Vibrio sp.-86 strain grown at 1 atm were abundant in the order of aspartic acid, methionine, and glutamic acid and those at 400 atm were abundant in the order of methionine, glutamic acid, and aspartic acid. The amino acids composition of Vibrio sp.-87 strain grwon at 1 atm were abundant in the order of methionine, glutamic acid, and aspartic acid and those at 400 atm were abundant in the order of methionine, glutamic acid, and isoleucine.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.500-508
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• 1999

Several white-rot fungi collected from the mountains of Korea were evaluated for their ability to decolorize azo, polymeric, and reactive dyes. Strains CJ-105, CJ-212 and CJ-315, identified as Trametes sp., Pleurotus sp. and Fomes sp., respectively, showed higher potential for decolorization of those dyes in either solid or liquid media. For Trametes sp. CJ-105, 100ppm of Remazol Brilliant blue R and 500ppm of Acid Red 264 were completely decolorized after 2 days under liquid culture. The dominating ligninolytic enzyme existing in the culture broth was laccase (E.C. 1.10.3.2). Also, Pleurotus sp. CJ-212 and Fomes sp. CJ-315 showed similar patterns in decolorization of Remazol Brilliant Blue R and Acid Red 264. The extent of decolorization of the dyes in liquid culture was found to be proportional to the activities of the ligninolytic of decolorization of the dyes in liquid culture was found to be proportional to the activities of the ligninolytic enzymes produced by each strain. In addition to that Trametes sp. CJ-105 was highly effective in degradation of polycyclic aromatic hydrocarbons and pentachlorophenol by the activity of the ligninolytic enzymes produced. In this study, we found that white-rot fungi, Trametes sp. CJ-105(KFCC 10941), Pleurotus sp. CJ-212(KFCC 10943) and Fomes sp. CJ-315(KFCC 10942), were effective in decolorizing a wide range of structurally different synthetic dyes, as well as some chemical compounds which are known to be hardly degradable.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.162-168
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• 1998

The characteristics of demulsification of petroleum emulsion by Streptomyces sp. 8321 were investigated. Demulsification ability of Streptomyces sp. 8321 appeared to be confined within the spores. Spore surface hydrophobicity was increased with culture age stimulating the demulsification ability. Over $1.1{\times}10^8spores/ml$ completely demulsified kerosene-0.2% Triton X-100 (2:1) emulsion. Among the low viscosity hydrocarbons, hydrocarbons with longer chain such as n-hexadecane and diesel were more rapidly demulsified. However, only 20-30% of the emulsion with high viscosity hydrocarbons was demulsified after 24 hours. Oil-in-water emulsions made by Corexit, Finalsol and BP series surfactants were completely demulsified within one minute. Demulsification rate ($t_{1/2}$) of oil-in-water emulsions made by Corexit 7664, 8667, Triton X-100 and Tween 80 decreased as their concentration increased. In case of water-in-oil emulsion made by Seagreen, $t_{1/2}$ was over 24 hours. Therefore, demulsification ability of Streptomyces sp. 8321 was more effective on oil-in-water emulsions.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.71-76
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• 2002

Soil samples were screened for actinomycete strains capable of producing phospholipase D, and a strain, Streptomyces sp. YU100, showing a high transphosphatidylation activity was isolated. This strain secreted phospholipase D in a culture broth after 12 h of cultivation, and its productivity continued to increase for 36 h of fermentation. In addition, its transphosphatidylation rate of phosphatidylcholine to phosphatidylserine was almost $68\%$ within 1 h. The morphological and chemotaxonomical characteristics showed that this strain could be classified as a number of the Streptomycetaceae family, particularly due to the spiral form of its spore chain consisting of 60-70 smooth spores $(0.75{\times}1.0{\mu}m$) on an aerial mycelium, FA-2c type of fatty acid profile in the cell wall, and LL-DAP component in the cell wall peptidoglycan. A phylogenetic analysis of the 16S rDNA provided a clue that the strain YU100 was actually a member of the genus Streptomyces, because the determined sequence exhibited a higher homology with Streptomyes sp. ASB27, S. peucetius JCM9920, and S. griseus ATCC10137. A dendrogram based on the 16S rDNA sequences also showed a phylogenetic relationship between the strain YU100 and these strains. However, the strain YU100 has not yet been assigned to a particular species, because of absence of any other classified species with a high matching score.