• Journal of Korean Society of Environmental Engineers
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• v.37 no.7
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• pp.396-403
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• 2015

This study was investigated occurrence and distribution patterns of organophosphorus flame retardants (OPFRs) in Nakdong River basin (mainstream, tributaries and sewage treatment plant (STP) effluents). 3 (TCEP, TCPP and TBEP) out of 9 OPFRs were detected in 6 out of 20 sampling sites (mainstream and tributaries), The TCPP and TBEP concentration levels in mainstream samples were ND~114.9 ng/L ng/L and ND~49.1 ng/L, respectively. And the TCEP, TCPP and TBEP concentration levels in tributary samples were ND~1,865.3 ng/L, ND~519.2 ng/L and ND~210.4 ng/L, respectively. 4 (TBP, TCEP, TCPP and TBEP) out of 9 OPFRs were detected in effluents of 11 STPs around the Nakdong River basin. The TBP, TCEP, TCPP and TBEP concentration levels in 11 STP effluents were ND~458.5 ng/L, ND~2,932.7 ng/L, ND~1,320.7 ng/L and ND~655.2 ng/L, respectively. According to the sampling season, change ranges of distribution patterns and detected concentrations of OPFRs were highly variable in the same sampling sites.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.334-341
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• 2000

To develop a nutrient solution for a closed hydroponic system in potato (Solanum tuberosum L.) 'Atlantic' and 'Superior' potatoes were grown with the nutrient solutions whose strengths were 0.25, 0.5, 1.0, and 1.5 of the concentration of the nutrient solution developed by the National Horticultural Experiment Station in Japan. The best results in potato growth and yield were obtained with 0.5 and 1.0 strength nutrient solutions, and nutrient compositions for potato were determined based on the 1.0 strength nutrient solution; $14.4me{\cdot}L^{-1}\;N,\;4.2me{\cdot}L^{-1}\;P,\;7.5me{\cdot}L^{-1}\;K,\;5.5me{\cdot}L^{-1}\;Ca$, and $3.5me{\cdot}L^{-1}\;Mg$ for stolon growth stage and $14.8me{\cdot}L^{-1}\;N,\;4.0me{\cdot}L^{-1}\;P,\;8.5me{\cdot}L^{-1}\;K,\;6.5me{\cdot}L^{-1}\;Ca$, and $3.0me{\cdot}L^{-1}\;Mg$ for tuber growth stage. To examine the suitability of the nutrient solutions developed for potato, the strengths of 1.0 (PS 1.0S), 0.75 (PS 0.75S), or 0.5 (PS 0.5S) were compared with half-strength of Japanese Horticultural Experiment Station' solution (JH 0.5S). Changes in pH, EC, and mineral concentrations in nutrient solutions depended more on solution strength and growth stage than on the type of nutrient solution. However, most elements in solution remained constant with plant age in PS 0.75S solution during stolon growth stage, and in PS 0.5S solution during tuber growth stage. The greatest growth and tuber yield was obtained in the standard strength solution (PS 1.0S), and potato solution developed in this experiment was recommended for hydroponic culture of potato in a closed system.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.279-282
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• 2000

The effect of three antifoam agents: PPG(polypropylene glycol), PEG(polyethylene glycol) and CA-110(aquous emulsion with 16% silicon oil component), was examined on the lincomycin production during cultivation of S. lincolnensis. Both PEG and PPG were effective in foam depressing during the flask cultures. As a result, the lincomycin production was enhanced upto about 400 mg/L in a optimized medium (OP-1) containing PEG or PPG. In contrast, the effect of antifoam agents in flasks was not remarkable for the various initial concentrations ranging from 0.5 g/L to 5 g/L with the basic medium(UP-1). But the lincomycin production in small fermentor showed the great different results in comparison with that in flasks under the same conditions. The lincomycin productions in small fermentor were 325 mg/L and 130 mg/L respectively for the following initial PPG concentrations, 0.5 g/L and 1 g/L.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.383-388
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• 2020

Elephant garlic (Allium ampeloprasum L.) has been reported to have several pharmacological effects. However, its anti-adipogenic effect and the possible molecular mechanisms have not yet been reported. In this study, we demonstrate that elephant garlic extracts suppress adipogenesis in 3T3-L1 adipocytes. Raw and steamed elephant garlic extracts (REG and SEG, respectively) suppressed the differentiation of adipocytes and cellular lipid accumulation. Of note, the anti-differentiation effect of REG treatment on 3T3-L1 cells resulted in cytotoxicity, whereas SEG-treated cells displayed no such cytotoxicity. Additionally, SEG treatment significantly reduced the adipogenesis-related gene expression of PPAR γ, C/EBPα, adiponectin, Ap2, and LPL. To our knowledge, these results are the first evidence of the anti-adipogenic effects of elephant garlic extracts on 3T3-L1 adipocytes.

• Journal of Environmental Health Sciences
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• v.11 no.1
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• pp.15-28
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• 1985

In order to analyze the water quality in artificial lakes in Chonnam area, a chemical and biological examination of Dongbock Lake and Changsung Lake was conducted from September to December 1983 and May 1984. A summary of the surveyed results is as follows 1. In Dongbock Lake, pH ranged from 7.2-8.1, D.O.: 8.2-12.6mg/l, B.O.D.: 4.4-22.1 mg/l, C.O.D.: 1.0-3.4rag/l, Cl$^-$: 5.9-11.9mg/l, Total-P: 0.001-0.071 mg/l, and Total -N: 0.016-0.697 mg/l, respectively. 2. In Changsung Lake, pH ranged from 7.2-8.1, D.O.: 8.1-9.8mg/l, B.O.D.: 0.9-2.9mg/l, C.O.D.: 1.9-3.4mg/l. Total- P: 0.006-0.016mg/l and Total -N:0.006-0.033mg/l, respectively. 3. The Phytoplankton identified in this investigation were distributed in a total of 46 genera and 76 spedes in Dongbock Lake 37 genera and 45 species in Changsung Lake. 4. In Dongbock Lake, it was found that the dominant algae were Melosira sp., Microcystis sp. and Synedra sp. in September Melosira sp. and Microcytis sp. in October, but Cymbella sp., Naviculla sp. and Nitzschis sp. were also observed in OctoberAsterionella sp., Melosira sp. and Microsystis sp. in November and Melosira sp., Asterionella sp sp. and Synedra sp. in December 1983. 5. In Changsung Lake, it was found that the dominant algae were Melosira sp., Lyngrbya sp. and Microcystis in September Melosira sp. and Synedra sp. in October and November and Melosira sp., Lyngbya sp. and Asterionella sp. in December 1983. The dominant algae were Melosira sp., Lyngbya sp. and Euglena sp. in May 1984. 6. It was found that the dominant algae in both Dongbock and Changsung Lakes were Microcystis sp., Melosira sp. and Asterionella sp.. Which are strongly related with water-bloom. Therefore, it could be suggested that the eutrophication phenomena is going to occur very easily in Dongbock Lake and possibly in Changsung Lake.

• Korean Journal of Microbiology
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• v.44 no.2
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• pp.156-163
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• 2008

In this study, we isolated 32 strains of kerosene degrading bacteria from oil contaminated soil by enrichment culture. Isolates were screened for kerosene degradation efficiencies and K14 were selected which had the highest removal efficiency for 1,000 mg/L of kerosene. K14 were identified as Pseudomonas aeruginosa by morphological, biochemical test and 16S rDNA analysis. The optimal culture condition were determined as initial inoculated cell concentration, 1.0 g/L; substrate concentration, 1,000 mg/L; temperature $30^{\circ}C$; pH 7. When we enforced batch test in this condition, K14 degraded 72% of kerosene with 1,000 mg/L during 72 hr. And, at low concentration (200 mg/L), K14 degraded 95.8% of kerosene during 48 hr. As a result, kerosene biodegradation by Pseudomonas aeruginosa K14 could be useful for clean up of groundwater and soil contaminated with crude oil.

• Preventive Nutrition and Food Science
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• v.10 no.4
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• pp.333-339
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• 2005

Three lactobacillus strains, two from infant feces, and one from cow's milk, were selected among 172 isolates, from multiple sources, for further study based on the antimicrobial activities against six strains of pathogenic bacteria and identified as Lactobacillus acidophilus. The strains revealed a wide scope of spectrum against pathogenic bacteria. Viable Lactobacillus acidophilus KH-l cell counts at pH 2.0 were slightly decreased to $1.42\times10^7$ CFU/mL from $4.18\times10^7$ CFU/mL, while remaining at $3.42\times10^7$ CFU/mL at pH 4.0 with the survival rate of $33.97\%\;and\;81.82\%$, respectively. At the concentration of $0.1\%$ oxgall, L acidophilus KH-l kept growing up to $3.12\times10^7$ CFU/mL with a mean growth rate constant (k) of 0.25, and cell number was slightly decreased to $1.21\times10^7$ CFU/mL (k=0.19) with $0.3\%$ oxgall, but remained at $7.6\times10^6$ CFU/mL (k=0.17) with $0.5\%$ oxgall. L. acidophilus KH-l had a $D_{60}$ value of 7.14, with viable cell numbers $1.4\times10^5$ CFU/mL after heat treatment at $60^{\circ}C$ for 30 minutes. Stability of L acidophilus KH-l at $-20^{\circ}C$ was significantly higher, when the strain was cultivated under the optimum growth temperature $(54.41\%\;and\;54.35\%)$ than at the temperature $(13.53\%)$.

• The Journal of the Korean Society for Microbiology
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• v.13 no.1
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• pp.75-79
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• 1978

There has been many investigations on phytoagglutinin and especially, Moon et al reported a number of research works on phytoagglutinins prepared from the Korean plants. The present report describes results of experiment on the biological effect of 14 Korean phytoagglutinins to microorganism for the first time. 1) Kaolin rubi and Ricinus communis L. among 14 different species of Korean phytoagglutinins had agglutinating activities to microoganisms. 2) Kaolin rubi agglutinated E. coli, Staph. aureus, Ps. aeruginosa, Prot. vulgaris, B. subtilis, Sal. typhi, Sh. dysenteriae, C. albicans and Sa. cerevisiae but Ricinus communis L. showed only agglutination of Sa. cerevisiae. 3) Agglutinating titers of Kaolin rubi to various microorganisms were 500-1,000 but titer of Ricinus communis L. was only 50. 4) Ricinus communis L. showed bactericidal action to Sa. cerevisiae but Kaolin rubi had no such effect.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.1
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• pp.57-65
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• 2014

In this paper, we investigate the properties of L-lower approximation operators as a generalization of fuzzy rough set in complete residuated lattices. We study relations lower (upper, join meet, meet join) approximation operators and Alexandrov L-topologies. Moreover, we give their examples as approximation operators induced by various L-fuzzy relations.

• KSBB Journal
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• v.17 no.1
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• pp.93-99
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• 2002

Two-stage fed-batch culture of Candide tropicalis that was designated primarily to cultivate the cell in the glucose medium (1st stage) and then produced the xylitol from xylose medium (2nd stage) was developed to improve a xylitol yield and productivity. In the growth stage, glucose was automatically supplied to the fermentor by pH-stat mode when the pH was up 5.7, When a feeding medium was added in order to reach the glucose and yeast extract concentrations up to 100 and 40 g/L, respectively, a high cell concentration and a relatively low ethanol concentration were obtained in 18.5 h culture. In the production stage, initial xylose concentration of 150 g/L was the most favorable for obtaining the final xylitol concentration and productivity. The addition of mineral salts was also enhanced a xylitol production. But the aeration rate was not significantly affected a xylitol production. When the addition of 16 g yeast extract and 232.5 g xylose powder at the production stage was used, xylitol yield and productivity were significantly increased. With these conditions, xylitol concentration, yield and productivity of 108.9 g/L, 74%) and 3.3 g/L·h, respectively, were obtained in a final volume of 1.58 L. The further addition of 16 g yeast extract and 232.5 g xylose powder increased the working volume partly (1.67 L) and resulted in a relatively high xylitol concentration, yield and productivity of 193 g/L, 70% and 3.6 g/L·h, respectively.