• The Korean Journal of Mycology
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• v.11 no.3
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• pp.115-119
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• 1983

The bioconversion of progesterone by Aspergillus phoenicis has been studied. The metabolism in the conditions of experiment gave $11{\alpha}-hydroxyprogesterone$ as main product. The concentration of $11{\alpha}-hydroxyprogesterone$ increased monotonically and leveled off after 40 hours of incubation. Addition of glucose into the medium reduced considerably the time for attaining limiting concentration of $11{\alpha}-hydroxyprogesterone$. The increase in initial progesterone concentration did not affected the percentage of conversion nor the time required for termination of the reaction. But it could not be represented as first order reaction with respect to progesterone concentration. The degree of inhibition of enzymes by organic solvents depended upon the concentration of solvents. At low solvent concentration, acetone proved to yield the highest conversion.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.257-260
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• 2001

BCNU 106, 154 and 171 was isolated in the areas contaminated by high concentrations of organic solvents. These strains had the tolerance to almost all kinds of organic solvents used in this study. Especially, it was interested that BCNU 106, and 171 had the tolerance to meta-, para- and ortho. xylene. And 3 strains had high MIC (minimal inhibition concentrations).

• Journal of Life Science
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• v.21 no.5
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• pp.700-705
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• 2011

Using enrichment procedures, we isolated organic solvent-tolerant Bacillus sp. BCNU 5005 from waste water and soil in the Ulsan industrial plant region. BCNU 5005 had a maximum similarity of 98% with B. subtilis and was designated as B. subtilis based on phylogenetic analyses using 16S rDNA sequences. Generally, most bacteria and their enzymes are destroyed or inactivated in the presence of high concentrations of organic solvents. However, the lipase activity of B. subtilis BCNU 5005 was very stable in the presence of various kinds of solvents (25%, v/v) except chloroform, ethylbenzene and decane. Furthermore, BCNU 5005 was determined to have a degradative ability towards organic solvents. This organic solvent tolerant Bacillus sp. BCNU 5005 could be used as a new potential resource for biotransformation and bioremediation.

• Korean Chemical Engineering Research
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• v.44 no.1
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• pp.92-96
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• 2006

Enzymes in organic media afford many advantages such as chiral synthesis and resolution, modification of fats and oils and production of biodegradable polymers. However, the nature of solvents influences the activity and stability of enzymes, and the presence of organic solvents always constitute a risk of enzyme inactivation. Heat-shock protein Hsp90, one of the molecular chaperone, was applied for understanding of enzyme inactivation and for increasing of enzyme stability in water-miscible organic solvent. Hsp90 showed stabilization effect on HRP in the 30％ of DMSO, in the 30％ and 50％ of dioxane. Hsp90 also showed reactivation effect on the inactivated HRP by water-miscible organic solvent such as dioxane and DMSO. In addition, structural analysis using fluorescence spectrophotometry and circular dichroism showed that exposure of HRP in water-miscible organic solvent caused appreciable conformational changes and enzyme inactivation, and the unfolded HRP by water-miscible organic solvent was refolded by Hsp90.

• Resources Recycling
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• v.28 no.1
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• pp.40-46
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• 2019

The solvent extraction of Tb(III) from hydrochloric acid solution was investigated by employing single organophosphorus (D2EHPA, PC88A and Cyanex 272), its mixture with Alamine 336 and ionic liquids with Aliquat 336. The equilibrium pH after the extraction with extractant mixtures and ionic liquids was higher than that by single extractants. Among the mixtures and ionic liquids, only the ionic liquid with Cyanex 272 and Aliquat 336 showed synergism to the extraction of Tb(III). The extraction percentage of Tb(III) by the extractant mixtures was lower than that by single extractant and the extraction order was in the following order : D2EHPA + Alamine 336 > PC88A + Alamine 336 > Cyanex 272 + Alamine 336. The extraction order of Tb(III) by the ionic liquids was Cyanex 272 + Aliqaut 336 > PC88A + Aliquat 336 > D2EHPA + Aliquat 336.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.1985-1994
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• 2000

This research was designed to investigate the effect of initial adsorbed amount of phenol, temperature, and pH on the desorption reaction of phenol from spent activated carbon loaded with phenol. Methanol, acetone, and N,N-dimethylformamide( DMF) were used as test organic solvents. The initial adsorbed quantities of phenol investigated here were 166.1mg/g, 180.7mg/g, and 197.9mg/g. The effect of temperature was evaluated from 15 to $55^{\circ}C$ with an interval of $10^{\circ}C$, while that of pH was investigated under acidic. neutral. and alkaline conditions. The extent of phenol desorption was proportional to the strength of dipole moment such as methanol < acetone < DMF. Over 90% desorption of phenol was achieved by acetone and DMF. The quantity of des orbed phenol by the organic solvents decreases with increasing the initial adsorbed amount of phenol. DMF is affected least by the initially adsorbed amount of phenol. An increase in reaction temperature leads to higher desorption of phenol. Desorption reaction by methanol is most sensitive to the temperature. As the pH of solvents increases. the desorption rate is also increasing. At pH=12. the desorption rate of phenol by methanol increases sharply by 10%. Although methanol demonstrated the weakest desorption power. the desorption capacity of methanol would approach that of acetone and DMF by adjusting temperature and pH. Methanol may emerge as a promising solvent for removing phenol from activated carbon because of acceptable regeneration efficiency as well as relatively cheap price.

• Applied Biological Chemistry
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• v.37 no.5
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• pp.397-401
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• 1994

Bioreduction with active dried baker's yeast proceeded smoothly in n-hexane, pentane or petroleum ether as an organic solvent system. Ethyl(1) and octyl 3-oxohexanoate(2) were reduced to $({\underline{R}})-ethyl(3)$ and $({\underline{S}})-octyl$ 3-hyroxy-hexanoate(4) with high enantiomeric excess, respectively.

• KSBB Journal
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• v.11 no.1
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• pp.100-106
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• 1996

The extraction of taxol and baccatin III from the ground needles of Taxus cuspidata were carried out by using supercritical carbon dioxide with and without cosolvents such as ethylacetate and methanol at 300 bar and 313K. Taxol is a promising anticancer agent and baccatin III is a precursor of semisysthesis of taxol. The taxol and baccatin III contents in the extracts were determined by a HPLC. The highest yields of taxol and baccatin III could be obtained by the supercritical extraction with 3wt% methanol and ethylacetate, respectively, as cosolvents. It was also found that the selectivity of taxol and baccatin III were 0.117 and 1.245wt%, respectively, with 0.7wt% ethylacetate, which demonstrated that the selectivity of taxol and baccatin III were increased about 1.8 and 19 times than those of conventional organic solvent extraction.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.802-808
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• 1996

Silicic acid(SA) was extracted with organic solvents from aqueous sodium silicate solutions acidified with dilute sulfuric acid. Tetrahydrofuran(THF), isopropyl alcohol and acetone were used as organic solvents. The extraction degree of Si and the removal efficiency of Na is determined according to kinds of solvent and the mixing ratios of solvent, sodium chloride and $H_2O$. Optimum conditions for the preparation of high purity SA were THF as an organic solvent, volume ratio of organic solvent/SA : 1 (organic solvent 10ml/10ml SA) and the amount of NaCl addition 2.5g/10ml SA. The extraction degree of Si and the removal efficiency of Na at that point were 86.2% and 99.95% respectively and the purity of SA was 99.96%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1204-1209
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• 2001

As a basic study to find bioactive principles for the hypolipidemic effect from natural sources, various biological influences of MeOH extracts of Thuja accidentalis L. and Juniperus chinensis var. horizontalis Nakai on rats were examined. The concentrates obtained from the organic layer and aqueous layer fractions of each species were orally administered to rats and then their effect on the body weight, organ weight, serum lipids profile, and blood glucose concentration were examined. Among the samples tested, the organic layer of Juniperus chinensis var. horizontalis exhibited the possibility of the hypolipidemic effects. The corresponding layer was chromatographed to give three fractions and reexamined their effects on rats. The results demonstrated that the fraction corresponding for the R$_{f}$ 0.4~0.7 which was the mixture of many minor components showed the effect of lowering the blood-lipid bevel effectively without any side effects. Besides, communic acid, identified from and isolated as a major component of the species exhibited the possibe hypolipidemic effects.s.