• Microbiology and Biotechnology Letters
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• v.24 no.3
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• pp.357-363
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• 1996

For the production of D-lactic acid from DL-2-chloropropionic acid, about 80 strains of bacteria capable of assimilating DL-2-chloropropionic acid as a sole carbon and energy source were isolated from the soil. JH-007 strain that showed the higest productivity of D-lactic acid and didn't produce L-lactic acid from DL-2-chloropropionic acid was selected from them and identified as Pseudomonas sp. The optimal conditions for the production of D-lactic acid from DL-2-chloropropionic acid were examined. The resting cells of JH-007 cultured in LB medium containing 3 g/l of DL-2-chloropropionic acid were used as an enzyme source. The reaction mixtures for the maximal production of D-lactic acid were consist of 10 g/l of resting cells and 3 g/l of DL-2-chloropropionic acid in 125 mM sodium carbonate buffer. The optimal pH for the reaction was 10.0 and the optimal temperature was 30$\circ$C. When 1 g/l of DL-2-chloropropionic acid was added intermittently to the reaction mixture under the above condition, 5.72 g/l of D-lactic acid was produced after incubation of 5 hrs. This amount of D-lactic acid corresponded to a 98.4% yields and the optical purity was 99.8%.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.2
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• pp.139-143
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• 2009

We examined the vertical distribution of specific microbial groups and the patterns of microbial community structure within the soil profile using phospholipid fatty acid (PLFA). Samples were collected from the soil surface down to 15 cm in depth from paddy and upland fields located in Daegu, Korea. The two fields have been fertilized with only chemical fertilizers N, P, K for 33 years. Principal component analysis of the PLFA signatures indicated that the composition of the soil microbial communities changed significantly with the cultivation practices and soil depth, suggesting that cultivation practices of paddy and upland fields had more significant influence on soil microbial community than the soil depth did. The soil microbial communities changed more drastically with soil depth in upland field than in paddy field, with making thicker soil surface in paddy field in terms of soil microbial community. The ratios of cyclopropyl/monoenoic precursors and total saturated/total monounsaturated fatty acids increased with soil depth, suggesting that the deeper soil horizons are more carbon-limited and anaerobic than surface soil. The community analysis using PLFAs as biomarkers revealed that Gram-positive bacteria and actinomycetes tended to increase in proportional abundance with increasing soil depth, while the abundance of Gram-negative bacteria and fungi were highest at the soil surface and substantially lower in the subsurface.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.129-132
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• 2000

In this research, we proposed the immobilization zone where the organic contaminant would be fixed, so that ground water could be prevented from the organic contaminants. The surfactant was adsorbed on the soil particles and the organic contaminants were partitioned into the hydrophobic tails of the surfactant in the immobilization zone. Surfactants with different molecular structures-SDDBS (sodium dodecylbenzenesulfonic acid), MADS (monoalkylated disulfonated diphenyl oxide), DADS (dialkylated disulfonated diphenyl oxide) - were used in this study. Up to the present, the research on the immolization simulated the saturated condition. But many site contaminated with organic contaminants and the zones where immobilization would be applied are unsaturated. In this research, in order to investigate the behaviors of surfactants and organic contaminants in unsaturated condition, the unsaturated columns were experimented, and their results were compared with the saturated case.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1009-1016
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• 2012

The purpose of this study was to determine the effects of organic fertilizers on soil properties and growth and quality of melon. Organic fertilizer was applied in soil at the rate of 0, 0.5, 1, 2N according to Rural Development Administration guideline in Korea. The fertilizer had no effects on plant growth-rate parameters, including plant height, leaf number, and leaf size. There were minor effects on the fruit quality parameters such as fruit weight, fruit length, fruit width, placenta and seed weights, sugar content, and starch content. Ascorbic acid level was decreased as fertilizer level was increased. The level of nitrate in groundwater increased with increased levels of N.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.168-171
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• 2001

Organobentonite modified with hexadecyltrimethylammonium (HDTMA) was used to quantify an adsorption of heavy metals. Based on preliminary experiments, optimal soil/solution ratio, a range of pH, and electrolyte were selected. Adsorption experiments of cadmium and lead were conducted to quantify an adsorption selectivity to bentonite and organobentonite. Adsorption of cadmium and lead to bentonite was increased with increasing a soil/solution ratio. Adsorption of cadmium and lead to bentonite was increased with increasing a soil/solution ratio. Adsorptions of heavy metal to organobentonite were slightly reduced relative to bentonite. This study used the principle of hard-soft-acid-base (HBAB) to interpretate an adsorption mechanism. Because of competition between cadmium and lead. adsorption of cadmium and lead was reduced in mixture of heavy metals. Adsorption selectivity.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.9-12
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• 2005

각기 다른 경로로 카드뮴에 오염된 두 토양에서 카드뮴을 중성인 물과 황산 수용액으로 용출하여 보았다. 토양은 자연에서 오랫동안 오염된 금속 폐 광산 토양과 한편으로는 오염되지 않은 토양을 인공적으로 오염시킨 것 두 가지를 재료로 사용하였다. 실험결과, 높은 카드뮴 농도에도 불구하고 자연오염 토양의 경우 추출용매가 물인 경우에는 카드뮴이 거의 용출되지 않았고 산 용액에서는 상대적으로 낮은 농도의 카드뮴이 꾸준히 용출되었다. 이에 반하여 인공오염토양의 경우 카드뮴의 용출량이 많아, 현실적으로 공장부지 등지에서 급격히 오염된 토양에는 산성비가 내릴 경우 카드뮴이 지하수를 오염시킬 위험성이 금속 폐광산등 자연적으로 오염된 토양에서보다 상대적으로 더 큰 것으로 나타났다. 특히 중성인 물에서도 인공오염토양 내 카드뮴의 초기 용출량이 크게 나타났는데, 이것은 공단부지 등에서 상대적으로 토양의 카드뮴 오염이 빠르게 진행된 지역의 지하수 등이 카드뮴 오염에 상대적으로 크게 노출되어 있음을 의미한다.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.127-134
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• 2017

Bottom ash (BA) has different macro- and micronutrients such as B, Mo, Fe, Ca, and Mg, providing useful resources for plant growth and soil quality. The objective of this study was to evaluate the applicability of artificial top-soil treated with BA in park area as a vegetation base material, especially for turfgrass growth. Collected BA was mixed with peat moss and clay at the ratio of 70:10:20 (w/w). In order to evaluate the park quality and turfgrass growth in park area, the artificial soil was applied with BA along with the control or without BA. Result showed that exchangeable K and P were increased by $11.4mg\;kg^{-1}$ and $163mg\;kg^{-1}$, respectively, compared to the control soil when the artificial soil was treated with BA. Microbial population and enzyme activity (Acid-phosphatase, APA) in artificial soil having BA also increased as 2 times and 10%, respectively, compared to the control soil. Comparing turfgrass growth and yield between general soil and artificial soil, about 2 times higher plant yield (fresh weight) was observed as artificial soil was applied comparing to general soil. Furthermore, nutrient concentration in turfgrass was averaged as 0.440% for $P_2O_5$, 0.456% for CaO, 1.198% for $K_2O$ and 0.188% for MgO that all values are higher than general soil (0.323% for $P_2O_5$, 0.416% for CaO, 0.610% for $K_2O$ and 0.173% for MgO). Application of BA can be useful for vegetation base material in park site.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.185-192
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• 1999

To assess the soil quality of Chonan City, soil analyses were conducted according to the 14 different sampling sites. The soil pH of the agricultural area near the expressway was lower than that of the other farming area, which indicated that this acidification was probably attributed to the acid rain caused by the traffic exhaust gas such as SOx and NOx. Acidification was more severe in the dry farming area than in the rice paddy area. All concentration of 6 different heavy metals (As, Cu, Cd, $Cr^{6+}$, Hg, Pb) and organic contaminants (cyanide, organic-p, PCBs, phenols) were found to be lower than the standard of soil pollution. The concentration of BTEX also lower than the standard of soil pollution. An assessment using the SPI (Soil Pollution Index). which was developed to estimate an overall soil quality, was performed. Each SPC (Soil Pollution Score) were evaluated with the results of the data from this study. The soil quality of most area of Chonan City was determined to Class 1 , which indicated that the soil was healthy.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.506-511
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• 1997

For the production of benzoylformic acid from DL-phenylglycine, 8 strains of bacteria capable of producing benzoylformic acid were isolated from soil. Among them, the strain YH-001 showed the highest activity for production of benzoylformic acid, and was partially identified as a Bacillus sp. For the production of benzoylformic acid, a reaction mixture and reaction conditions were optimized as follows: the reaction mixture contained 2 g of DL-phenylglycine and 50 g of wet cells in 1 l of 50 mM potassium phosphate buffer (pH 8.0) and the reaction was carried out at 40$circ$C with shaking. After 6 hr incubation, 1.01 g/l of benzoylformic acid was produced which coffesponded to a conversion yield of 50.5%.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.3
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• pp.266-273
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• 1983

In a series of studies on the chemical compositions and properties of organic matter from peats, volcanic ash soils and paddy rice soils, a comparative study on the composition and the fractional distribution of nitrogenous organic matters were undertaken for the elucidation on their characteristics. The results obtained are summerized as follows. 1. Gimpo and Peongtaeg peats showed higher content of organic matter, more than 60%, than Gimje and Yeongdong peats, and there is a great difference between the two groups in total-N, CEC and ash content. 2. The content of Lignin, Hollocellulose and Hemicellulose in organic matter was 12-25%, 15-31% and 7-14% respectively, and Gimpo peats were lots of Lignin content compared to others. 3. Sixty seven to eighty eight percent of the total-N in the soil was hydrolysable by 6 N-HCl and they were decreased in the order of volcanic ash soils (86.4%), mineral paddy soils (77.2%) and peats (72.3%). 4. The fractionations of acid hydrolysable organic-N were ${\alpha}$-amino acid-N(25-45%), unidentified-N (12-50%), amino sugar-N (1-7%) and ammonium-N (12-25%). 5. Almost same pattern in the amino acid composition of the acid hydrolysates of peat and soil organic matter was showed in the thin-layer chromatogram.