• KSBB Journal
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• 제14권6호
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• pp.747-753
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• 1999

Microbial surfactants are more effective and environmentally friendly than many synthetic surfactants. Sophorolipid, a glycolipid type microbial surfactant, is produced from C. bombiocola. Cultivation techniques to increase the productivity have been developed using various carbon sources and reactor setup, reaching its concentration upto 100-300 g/L. Due to its high productivity and non-toxicity, sophorolipid became one of the most promising alternative to synthetic surfactants. Fermentative production of sophorolipid depends primarily on the carbon sources, such as glucose and vegetable oils, and nitrogen sources. Chemical modification of the sophorolipid produces various derivative with different physical properties including hydrophile-liphophilie balance(HLB), emulsion formation, surface tension and dispersing ability. Commercial potentials of sophorolipid in the cosmetic, health care and environment clean-up industries have been discussed.

• The Korean Journal of Ecology
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• 제17권4호
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• pp.425-434
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• 1994

After two highly weathered soils were treated with glucose, ammonium nitrate, monobasic potassium phosphate and biocides, and incubated for 4 or 6 weeks, adsorption tests were carried out to determine their effect on P adsorption. Glucose addition generally decreased P adsorption. The addition stimulated microbial activity, which might contribure to the reduced adsorption, probably through chelation and anion competition. Consistent endency was not observed with N treatment. Addition of P initially decreased P adsorption, probably through blockage of adsorption sites. Biocides generally decreased adsorption, probably because the microbes that 몬 been killed. Soil 1 with naturally lower levels of C and higher levels of aluminium adsorbed more P than soil 2. These results suggest that in highly weathered soils, which are low in available P and high in exchangeable Al, cultivation techniques which increase soil organic matter will also result in higher levels of plant-available P.

• 한국해양바이오학회지
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• 제2권1호
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• pp.11-22
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• 2007

This aims to review natural products transformed by mimic intestinal metabolisms with microorganisms and hydrolytic enzymes, which exhibit enforced biological activity, higher extraction yield and identification of active components. In the process, transformation to the smaller active compounds with enzymes and microbes mimics the pharmacological action of natural products by intestinal bacteria. In order to establish conditions for the fermentation and enzyme reaction, it is required to choose several natural products for biotransformation and investigate the optimal conditions for the fermentation or the enzyme reaction such as composition, temperature, pH, inoculum, and cultivation time. It is expected an increase of the internal absorption of the active materials without regard to the intestinal microbes or its ability through biosynthesis of the active materials by the microbes and enzymes. And this techniques can be applied to biotransformation of natural products such as sesaminol, resveratrol, 1-deoxy nojirimycin, naringenin, quercetin, and baicalin and to the metabolism study using the animal model.

• Preventive Nutrition and Food Science
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• 제5권4호
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• pp.179-183
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• 2000

$\beta$-1,4-Mannotriose was prepared b he enzymatic hydrolysis of white copra meal (WCM) and the subsequent elimination of monosaccharides from the resultant hydrolysate with a yeast. The enzyme system from sunflower seed hydrolyzed WCM and produced monosaccharides and $\beta$-1,4-mannotriose without other oligomers at the final stage of the reaction. WCM(50g) was hydrolyzed at 5$0^{\circ}C$ and pH 4.5 for 24 hr with crude enzyme solution (500 mL) from sunflower seed. By the elimination of monosaccharides from the hydrolysis products with a yeast (Candida glaebosa), 8.1 g of crystalline mannotriose was obtained without the use of chromatographic techniques. After 48hr of yeast cultivation, the total sugar content decreased from 4.6% to 3.5%, whereas the average degree of polymerization increased from 2.3 to 3.1.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.29-31
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• 2002

Purpose of the 765kV trial operation conducted for the first time in our country are performance verification of domestic developed equipment(765kV M.Tr, GIS,etc) and extraction of problem in advance to commercial operation and cultivation of operation ability. The trial operation of 765kV substation was finished successfully under the positive supports of institutes. manufactures. and constructers. It is expected that extraction of problems in advance and accumulation of operation techniques through the trial operation of 765kV substation will be contributed largly to the realization of the without a hitch operation of 765kV system.

• 한국작물학회지
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• 제46권5호
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• pp.345-347
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• 2001

This study was conducted to evaluate the effect of insecticides on control of Spodoptera exigua, growth characteristics, and dry root yield in the cultivation of Alisma plantago after early maturing rice cropping. All pesticides treated had no effect on growth and flowering rate of Alisma plantago. The major insecticides were teflubenzuron Wp, 5%, tebufenozide Wp, 8%, iufenuron Ec, 5%, and tebufenozide Wp, 5%. Dry root yield were increased largely with tebufenozide Wp, 5%(20 g/20 l), insecticide than the other insecticides and no control. All insecticides had no injury with standard dosage. On the other hand, all insecticides had slight injury in the double dosage level for the Alisma plantago.

• Natural Product Sciences
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• 제21권4호
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• pp.261-267
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• 2015

Compared to their terrestrial and marine counterparts, little is known about the capacity of freshwater-derived actinomycete bacteria to produce novel secondary metabolites. In the current study, we highlight the disparities that exist between cultivation-independent and -dependent analyses of actinomycete communities from four locations in Lake Michigan sediment. Furthermore, through phylogenetic analysis of strains isolated from these locations, we identified a Streptomyces sp., strain B025, as being distinct from other Streptomyces spp. isolated from sediment. Upon fermentation this strain produced a rare class of eight-membered lactone secondary metabolites, which have been for their antitumor properties. We used spectroscopic and chemical derivitization techniques to characterize octalactin B (1) in addition to its corresponding novel, unnatural degradation product (2).

• Food Science and Biotechnology
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• 제14권6호
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• pp.818-822
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• 2005

Beta-1,4-mannotriose was prepared by the enzymatic hydrolysis of poonac and the subsequent elimination with yeast of monosaccharides and disaccharide from the resultant hydrolysate. The enzyme system hydrolyzed poonac and produced monosaccharides, disaccharide and ${\beta}$-1,4-mannotriose without other oligomers at the final reaction stage. Poonac (50 g) was hydrolyzed at $50^{\circ}C$ and pH 6 for 48 hr with the crude enzyme solution (500 mL) from Trichoderma harzianum. The elimination of monosaccharides and disaccharide from the hydrolysis products with a yeast (Candida guilliermondii) produced 10.5 g of crystalline [${\beta}$-1,4-mannotriose without the use of chromatographic techniques. After 48 hr of yeast cultivation, the total sugar content fell from 4.8% to 3.4%, and the average degree of polymerization (D.P) rose from 2.5 to 3.2. The preparation method presented was confirmed to be suitable for the preparation of mannotriose from poonac.

• 한국작물학회지
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• 제46권5호
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• pp.348-351
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• 2001

This study was conducted to evaluate the control effect of fungicides on control of brown leaf blight, growth characteristics, and dry root yield in the cultivation of Alisma plantago after early maturing rice cropping. All fungicides treated had no effect on the growth and flowering rate of Alisma plantago. The major fungicides were mancozeb Wp, 75%, chlorothalonil Wp, 75%, dithianon Wp, 43%, difenoconazole Wp, 10%, benomyl Wp, 50%, and propineb Wp, 70%. Dry root of yield were increased largely with chlorothalonil Wp, 75%(33 g/20), fungicide than the other fungicides and control. All fungicides had no injury with standard dosage. On the other hand all fungicides had slight injury in the double dosage level for the Alisma plantago.

• Journal of Microbiology and Biotechnology
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• 제3권3호
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• pp.194-198
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• 1993

${\beta}-1$, 4-Mannobiose was prepared by the enzymatic hydrolysis of brown copra meal and the subsequent elimination of mono-saccharides from the resultant hydrolysate with a yeast. The enzyme system hydrolyzed brown copra meal and produced monosaccharides and $\beta$-1, 4-mannobiose without other oligomers at the final stage of the reaction. Brown copra meal (30 g) was hydrolyzed at $50^{\circ}^C$ and pH 5 for 48 hr with the crude enzyme solution (300 ml) from Penicillium purpurogenum. By the elimination of monosaccharides from the hydrolysis products with a yeast (Candida parapsilosis var. komabaensis k-75), 5.2 g of crystalline mannobiose was obtained without the use of chromatographic techniques. After 50 hours of yeast cultivation, the total sugar content fell from 3.5% to 2.4%, and the average degree of polymerization rose from 1.8 to 2.2.