• 한국해양학회지
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• v.14 no.1
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• pp.1-5
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• 1979

In order to investigate water quality of coastal waters, samples were collected from the six coastal areas of Korean peninsula during summer of 1977, and analyzed for Cd, Cu, Fe, Pb and Zn by atomic absorption spectrophotometry. The results showed no significant heavy metal pollution in most parts of the studied areas in comparison with results of other countries in literature. However, strong possibility of some specific heavy metal pollution is shown in the specific areas, such as Cu and Pb in the Sea off Cunsan, Pb in Kwangyang Bay and Cd and Pb in Ulsan Bay.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.19-22
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• 2007

Acetohydroxyacid synthase (E.C.2.2.1.6., AHAS) is the enzyme that catalyses the first step in the synthesis of the branched-chain amino acids valine, leucine and isoleucine. The AHAS gene (TIGR access code HI2585) from Heamophilus influenzae was cloned into the bacterial expression vector pET-28a and expressed in the Escherichia coli strain BL21(DE3). The expressed enzyme was purified by $Ni^{2+}-charged$ HiTrap chelating HP column. The purified enzyme appears as a single band on SDS-PAGE with a molecular mass of about 63.9 kDa. The enzyme exhibits absolute dependence on the three cofactors FAD, $MgCl_{2}$ and thiamine diphosphate for activity. Specific activity of purified enzyme has 3.22 unit/mg and optimum activity in the pH 7.5 at $37^{\circ}C$. This enzyme activity has an effect on the buffer. When comparing the enzyme activity against the organic solvent, it followed in type and the difference it is but even from the aqueous solution where the organic solvent is included with the fact that the enzyme activity is maintained.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.432-436
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• 1993

The improvement of superior black soybeans could be accomplished through maintenance and use of black soybean collections. This experiment was carried out to select pure-line from the domestic black soybean genotypes, and survey some agronomic characteristics of the collections. Nine hundred and sixty five lines of black soybeans were collected in 197 locations on spring, 1991. Higher distribution was present in broad leaves, purple flower color and tawny pubescence color which were approximate to be 97, 90 and 98%, respectively. In pod color of black soybean collections, 60% was brown and 27% was light brown and 10% was dark brown. The 61 to 70 days were required for flowering in 61 % of the collections. Growing days of 51 % of black soybean collections ranged 121 to 130, and those of 37 % were over 131 days.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.437-441
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• 1993

The improvement of superior black soybeans could be accomplished through maintenance and use of black soybean collections. A collection of 965 black soybean lines currently grown by farmers was made in 197 locations on spring, 1991. This study was carried out to evaluate them as useful germplasm. Seed characteristics of black soybean collections were evaluated for black soybean breeding for seed quality. The 100-seeds weight of 929 black soybean genotypes were distributed from 6.9 to 48.1 gram. The maximum and minimum 100-seeds weight were derived from Chungnam and Jeonbuk province, respectively. l00-seeds weight was heavier in middle and late maturity group, as maturity was later, whereas no tendency was shown in early maturity group. Length, width and thickness of the collected black soybean seeds were 9.5$\pm$1.5mm, 7.3$\pm1.3mm and 7.3$\pm1.2mm, respectively. Black soybean collections with yellow seed embryo was 72% and the others were green seed embryo.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.4
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• pp.371-378
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• 1987

Free and total amino acids of before and after the heating of the small shrimps were analysed quantitatively, in order to confirm the role of amino acids as important precursors of cooked odor components. Differences of free amino acids contents of the three samples were slightly reconized but free amino acids contents of all sample decreased as about half by heating, It seems that decreased amino acids participate In volatile components of the Small Shrimps. (Sergia lucens Hancen, Euphausia Surperba and Euphausia pacifica Hancen). The amino-carbonyl model reaction was carried out, in order to confirm formation mechanism of volatile compounds of the small shrimps during cooking. The model systems constituted by diluted solutions. of glucose and amino acids (proline, taurine and betaine) the most containing in small shrimps. The volatile odor concentrates of model system were obtained by simultaneous distillation and extraction with Nickerson's apparatus. The odor concentrates of model systems(I, III) had not small shrimp-like odor and main compounds were 1,4,5,6-tetrahydro-2-acetopyridine and 2-acetyl pyridine. In model system II, hetero ring nitrogen and sulfur compounds identified in small shrimps were not did.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.3
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• pp.165-170
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• 2013

In this study, physico-chemical properties and environmental fate were investigated and ecotoxicity tests using fish, daphnia and algae were conducted for an initial ecological risk assessment of 1,2-Benzisothiazol-3-one. Due to low volatility of the test substance under environmental conditions, it is likely to distributed in soil and water environment. The compound has low adsorption in the soil, with low bioconcentration potential. Acute toxicity results showed that 96 h-$LC_{50}$ for Oryzias laties was 4.7 mg/L (measured) and 48h-$EC_{50}$ for Daphnia magna was 3.3 mg/L (measured). In a growth inhibition test with Pseudokirchneriella subcapitata, 72 h-$EC_{50}$ was 0.456 mg/L (growth rate, nominal) and 0.262 mg/L (yield, nominal). Using the acute toxicity value of algae, predicted no-effect concentration (PNEC) in the aquatic environment was determined to be 2.62 ${\mu}g/L$ using an factor of 100. According to globally harmonized system (GHS), the compound was categorized as aquatic acute 1 for algae, while it was categorized as aquatic acute 2 for fish and daphnia. This screening assessment suggests that the test substance may pose ecological risks in the aquatic environment.