• Journal of Soil and Groundwater Environment
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• v.16 no.5
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• pp.74-81
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• 2011

The fluorene-degrading strain Sphingobacterium sp. KM-02 was isolated from PAHs-contaminated soil near a mineimpacted area by selective enrichment techniques. Fluorene added to the Sphingobacterium sp. KM-02 culture as sole carbon source was 78.4% removed within 120 h. A fluorene degradation pathway is tentatively proposed based on identification of the metabolic intermediates 9-fluorenone, 4-hydroxy-9-fluorenone, and 8-hydroxy-3,4-benzocoumarin. Further the ability of Sphingobacterium sp. KM-02 to bioremediate 100 mg/kg fluorene in soil matrix was examined by composting under laboratory conditions. Treatment of microcosm soil with the strain KM-02 for 20 days resulted in a 65.6% reduction in total amounts. These results demonstrate that Sphingobacterium sp. KM-02 could potentially be used in the bioremediation of fluorene from contaminated soil.

• Nutritional Sciences
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• v.7 no.3
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• pp.144-150
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• 2004

We have investigated the effect of calcium spirulan(Ca-SP) isolated from a blue-green alga Spirulina platensis, which is a sulfated polysaccharide chelating calcium and mainly composed of rhamnose and fructose, on invasion of both B16- BL6 melanoma cells, Colon 26 carcinoma and HT-1080 fibrosarcoma cells through reconstituted basement membrane (Matrigel). Ca-SP significantly inhibited the invasion of these tumor cells through Matrigel/fibronectin-coated filters in a concentration-dependent manner. Ca-SP also inhibited the haptotactic migration of tumor cells to laminin, but it had no inhibitory effect on tumor cell migration to fibronectin-coated filters. Ca-SP prevented the adhesion of B16-BL6 cells to Matrigel- and laminin-substrates but did not affect the adhesion to fibronectin. The pretreatment of tumor cells with Ca-SP inhibited the adhesion to laminin in a concentration-dependent fashion, while the pretreatment of laminin-substrates did not. Ca-SP had no effect on the production and activation of type IV collagenase in gelatin zymography. In contraset, Ca-SP significantly inhibited degradation of heparan sulfate by purified heparanase. The experimental lung metastasis was significantly reduced by co-injection of B16-BL6 cells with Ca-SP in a dose-dependent manner. Seven intermittent ⅰ.ⅴ. injection of 100$\mu\textrm{g}$ of Ca-SP caused a marked decrease of lung tumor colonization of B16-BL6 cells in a spontaneous lung metastasis model. These results suggest that Ca-SP, a novel sulfated polysaccharide, could reduce the lung colonization of B16-BL6 melanoma cells in experimental metastasis model, by inhibiting the tumor invasion of basement membrane Matrigel, probably through the prevention of the adhesion and migration of tumor cells to laminin-substrate and of the heparanase activity.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.952-964
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• 2005

The diesel-degrading activities of biofilms sampled from petroleum-contaminated groundwaters in urban subway drainage systems were examined in liquid cultures, and the microbial populations of the biofilms were characterized by denaturing gel gradient electrophoresis (DGGE) and 16S rDNA sequence analysis. Biofilm samples derived from two sites (19 K and 20 K) at subway Station N and Station I could degrade around $80\%$ of applied diesel within 20 and 40 days, respectively, at $15^{\circ}C$, and these results were strongly correlated with the growth patterns of the biofilms. The closest phylogenetic neighbor of a dominant component in the 19 K biofilm was Thiothrix fructosivorans strain Q ($100\%$ similarity). Four dominant strains in the 20 K biofilm were closely related to Thiothrix fructosivorans strain Q ($100\%$ similarity), Thiothrix sp. CC-5 ($100\%$ similarity), Sphaerotilus sp. IF14 ($99\%$ similarity), and Cytophaga-Flexibacter-Bacterioides (CFB) group bacterium RW262 ($98\%$ similarity). Three dominant members in the Station I biofilms were very similar to uncultured Cytophagales clone CRE-PA82 ($91\%$ similarity), Pseudomonas sp. WDL5 ($97\%$ similarity), and uncultured CFB group bacterium LCK-64 ($94\%$ similarity). The microbial components of the biofilms differed depending on the sampling site. This is the first report on the isolation of clones highly similar to Thiothrix fructosivorans and Thiothrix sp. from biofilms in petroleum-polluted groundwaters, and the first evidence that these organisms may play major roles in petroleum degradation and/or biofilm-development.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.57-63
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• 1991

A strain J-19 was isolated from soil, produced lipase which has resistant against alkali and linear alkylbenzene sulfonate. The strain was identified as Pseudornonns sp.. The enzyme was purified by ammonium sulfate precipitation, DEAE-Sephadex and Sephadex G- 100 column chromatography. The specific activity of the purified enzyme was 35 unit/mg protein and the yield of enzyme activity was 17%. The purified enzyme showed a single band on polyacrylamide disc gel electrophoresis. Mo1ecul;tr weight of the purified enzyme was estimated about 36,000 by Sephadex GI00 gel filtration and SDS-polyacrylarnide gel electrophoresis. The optimum pH and temperature were pH 10.0 and $30^{\circ}C$, respectively. Activity of the purified enzyme was increased 2-fold by the addition of 0.1% linear alkylbenzene sulfonate and 2.5- fold by the addition of 0.05% Tide. This enzyme remained stable from pH 8.0 to 10.0 and stable up to $40^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.935-939
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• 1996

A Candida sp. strain was isolated from honeycombs and used to produce erythritol, which was identified by HPLC and gas chromatography-mass spectrometry. This strain grown in the YPD medium containing 100 g/l of glucose was able to produce 21 g/l of erythrtiol without formation of by-products such as glycerol and ethanol. The yield of erythritol production was further improved by growing in the YPD medium containing 300 g/l of sucrose. The maximum erythritol concentration, 80.2 g/l was obtained with an erythritol yield of 0.345 g erythritol/g sucrose and productivity of 0.472 g/l hr.

• Korean Journal of Veterinary Research
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• v.22 no.2
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• pp.139-147
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• 1982

A total of 133 isolates of yeast-like fungi was tested for sensitivity to seven different antifungal agents. The yeast-like fungi tested were isolated from the milk from normal or mastitic bovine quaters or from bovine feces. They were 5 Candida albicans (C. albicans) isolates, 63 C. krusei, 27 C. tropicalis, 5 C. parapsilosis, 10 Torulopsis glabrata, 6 Rhodotorula sp., 6 Hansenula sp. and 1 Pichia sp. isolate. The antifungal agents tested were nystatin, griseofulvin, cycloheximide, 5-fluorocytosine, miconazol, clotrimazole and tolnaftate. In general, clotrimazole, miconazol and 5-fluorocytosine were more effective in antifungal activity in vitro against the test organisms than the rest of the agents tested. However, some of the isolates showed higher resistance to certain antifungal agents compared to the other isolates of the some species. They were: 1 C. albicans isolate to 5-fluorocytosine; 1 C. albicans to 5-fluorocytosine, miconazol and clotrimazole; 1 C. krusei to 5-fluorocytosine and cycloheximide; and 11 C. tropicalis isolates to cycloheximide. The minimum inhibitory concentrations(MIC) of clotrimazole were $12.5{\mu}g/ml$ or lower for all isolates tested except one C. albicans isolate, for which MIC of the drug was $100{\mu}g/ml$. On the other hand, the MIC's of cycloheximide were $6.5{\mu}g/ml$ or lower for all isolates except the following; all isolates of C. albicans ($100{\mu}g/ml$), C. pseudotropicalis ($200{\mu}g/ml$) and Rhodotorula sp. ($25-50{\mu}g/ml$), 11 C. tropicalis isolates ($100{\mu}g/ml$) and 1 C. krusei isolate ($200{\mu}g/ml$).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.1
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• pp.41-48
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• 1993

Using the eight-year-working diaries($1984{\sim}1991$) of the fishing co-operative in Tonggui-ri, Cheju-do, as well as the records of consignment sale in the fish trust market as the corporate body in Aewol-up, the results have been analyzed as follows. 1. The monthly catch of Turbo cornutus was high from September through December, representing $58.2\%$ of the annual total catches. The maximum sustained yield(MSY) of this stock was estimated to be 2.5 tons. 2. The maximum sustained yields of Haliotis spp. and Sulculus sp. were estimated to be 800kg and 750kg, respectively. 3. The maximum sustained yields of Stichopus sp. and Octopus sp. were 500kg and 2, 500kg, respectively. 4. The total yield of Hizikia fusiforme has been decreasing a little and that of Gelidium sp. has been increasing. The total yield of Gelidium sp. in 1984 was about 5 times greater than that in 1990. 5. The daily catchability by divers have been high at thirties, and the individual mean working day of divers was 101 per year. 6. The consignment sale rates were $100\%$ each for Turbo cornutus, Hiziki fusiforme and Gelidium sp., $25.5\%$ and $61.1\%$ for Haliotis sp. and Stichopus sp. respectively, and $0\%$ each for Sulculus sp. and Octopus sp.

• Korean Journal of Ichthyology
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• v.11 no.2
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• pp.143-148
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• 1999

Two sibling species of the genus Platycephalus collected from the South and West Sea of Korea were reviewed based on the several meristic and morphological characters, electrophoresis of muscle protein, and LDH and MDH isozyme. Counts and morphometric characters of Platycephalus indicus were different from those of Platycephalus sp. by having 18~20 pectoral fin rays (16~19 in Platycephalus sp.), 70~80 scales of lateral line (83~100), 10.2~13.1% eye diameter (10.9~15.5%), 14.5~18.1% interorbital width (11.8~17.8%), dark brown of body color (light brown) and dark brown of pectoral and ventral fin outside (light brown and pale). The number of soluble protein bands in muscle separated by polyacrylamidegel electrophoresis was 16 and 18 from P. indicus and Platycephalus sp, respectively, and each bands showed their characteristics in activated degree. The number of bands separated from LDH isozyme were 2 and 1 in P. indicus and Platycephalus sp. and in the case of MDH isozyme, 5 and 4 bands, respectively. So we were thought that P. indicus and Platycephalus sp. from Korea were different species each other.

• Journal of Life Science
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• v.27 no.2
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• pp.180-186
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• 2017

We investigated the antioxidant activities of water and ethanol extracts from Spirodela polyrhiza (SP) through in vitro assays. The total phenolic contents of SP water and ethanol extracts were 52.75-293.4 and 60.12-398.4 mg/g, respectively. The total flavonoid content of SP ethanol extract (38.25-159.4 mg/g) was higher than that of SP water extract (38.25-67.75 mg/g). The water and ethanol extracts from SP scavenged the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 2,2'-azino-di-2-ethyl-benzothia-zoline sulfonate (ABTS) radical in a dose-dependent manner in the concentration range of $100-2,500{\mu}g/ml$. The DPPH radical scavenging activity of the SP ethanol extract (2.87%-59.5%) was higher than that of the water extract (4.12%-81.52%). The $IC_{50}s$ of the DPPH radical scavenging activity of water and ethanol extracts were 2,100 and $1,034{\mu}g/ml$ respectively. The ABTS radical scavenging activities of SP water and ethanol extracts were 8.30%-83.16% and 13.11%-8.34% respectively. The $IC_{50}s$ of the ABTS radical scavenging activity of SP water and ethanol extracts were 798.7 and $457.1{\mu}g/ml$, respectively. The reducing power activities of SP water and ethanol extracts were 0.055-1.122 and 0.140-1.428, respectively ($500-4,000{\mu}g/ml$). The soybean lipoxygenase (SLO) radical scavenging activities of SP water and ethanol extracts were 157.7%-168.0% and 148.0%-169.4%, respectively. These results suggest that the water and ethanol extracts of SP may be useful as a potential antioxidant.

• Journal of Life Science
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• v.29 no.11
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• pp.1173-1178
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• 2019

The purpose of this study was to isolate an agar-degrading marine bacterium and characterize its agarase. Bacterium BK-1, from Gwanganri Beach at Busan, Korea, was isolated on Marine 2216 agar medium and identified as Agarivorans sp. BK-1 by 16S rRNA gene sequencing. The extracellular agarase, characterized after dialysis of culture broth, showed maximum activity at pH 6.0 and $50^{\circ}C$ in 20 mM Tris-HCl buffer. Relative activities at 20, 30, 40, 50, 60, and $70^{\circ}C$ were 67, 93, 97, 100, 58, and 52%, respectively. Relative activities at pH 5, 6, 7, and 8 were 59, 100, 95, and 91%, respectively. More than 90% of the activity remained after a 2 hr exposure to 20, 30, or $40^{\circ}C$; about 60% of the activity remained after a 2 hr exposure to $50^{\circ}C$. Almost all activity was lost after exposure to 60 or $70^{\circ}C$ for 30 min. Zymography revealed three agarases with molecular weights of 110, 90, and 55 kDa. Agarose was degraded to neoagarobiose (46.8%), neoagarotetraose (39.7%), and neoagarohexaose (13.5%), confirming the agarase of Agarivorans sp. BK-1 as a ${\beta}$-agarase. The neoagarooligosaccharides generated by this agarase could be used for moisturizing, bacterial growth inhibition, skin whitening, food treatments, cosmetics, and delaying starch degradation.