• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.523.2-523
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• 1986

The hydrolysis of olive oil was attempted with immobilized C. rugosa lipase in the reverse phase solvent system. (i.e. immobilized wet particles is dispersed in continuous phase olive oil or organic solvents containing olive oil). Sephadex LH-20 and LH-60 were used as the supports that can be used in organic solvents. The water content of wet particles of sephadex LH-20 and LH-60 were about 72% (w/w) and 85% (w/w), respectively Both swollen gels with 0.05M buffers adsorbed about 18% of lipase dissolved. They were easily dispersed in liquid olive oil or in organic solvents. The effects of organic solvents on the stability and catalytic activity of the lipase have been examined. The results revealed that isooctane is superior to the other solvents examined for enzymatic fat spliting in reverse phase system. Kinetics of enzymatic hydrolys of olive oil by immobilized lipase has been investigated in a batch reactor. Effects of pH and temperature on the lipase were studied. The substrate concentration was influenced positively on the thermal stability.

• Journal of Microbiology and Biotechnology
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• v.13 no.5
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• pp.647-650
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• 2003

In anhydrous organic solvents, the complexes formed between AOT (dodecylbenzene sulfuric acid sodium salt) and hemoproteins, such as hemoglobin, myoglobin, or cytochrome c, displayed remarkably higher activity than the hemoprotein powders to oxidize dibenzothiophene, a model compound of organic sulfurs contained in fossil fuels. In slightly hydrophobic organic solvents, such as ethyl acetate and butyl acetate, dibenzothiophene was completely oxidized catalytically by the cytochrome c-AOT complex with cumene hydroperoxide (${\alpha},{\alpha}-dimethylbenzyl$ hydroperoxide) as an oxidant. In highly hydrophobic organic solvents, such as decane and hexadecane, however, the activity of the cytochrome c-AOT complex decreased, presumably due to the aggregation of the hemoprotein-AOT complex in these solvents.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.2
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• pp.200-213
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• 1991

ln order to acquire the fundamental data for the organic solvents in bond and to contribute the health improvement of workers in deprtment of organic solvents in shoes manufacturing industries. The authors surveyed the contents of organic solvent in adhesive and determined the amount of volatilization of organic solvent by time and temperature with gaschromatography from March to September 1990. The results were as follows; 1) The kinds for organic solvents in bond were 9 that was Toluene, C-Hexane, N-Hexane, C-Hexanon, Aceton, Methyl Ethyl Keton, Dimethyl Formamide, Etyly Acetate. 2) Toluene and Methyl Ethyl Keton among the organic solvents in adhesive were over 80.18%. 3) The amount of volatilization of Methyl Cyclohexanone and Aceton by time and temperature were the most level than other compounds.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.2
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• pp.140-145
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• 2006

The behaviour of alginate immobilized and soluble watermelon (Citrullus vulgaris) urease in water miscible organic solvents like, acetonitrile, dimethylformamide (DMF), ethanol, methanol, and propanol is described. The organic solvents exhibited a concentration dependent inhibitory effect on both the immobilized and the soluble urease in the presence of urea. Pretreatment of soluble enzyme preparations with organic solvents in the absence of substrate for 10 min at $30^{\circ}C$ led to rapid loss in the activity, while similar pretreatment of immobilized urease with 50% (v/v) of ethanol, propanol, and acetonitrile was ineffective. Time-dependent inactivation of immobilized urease, both in the presence and in the absence of urea, revealed stability for longer duration of time even at very high concentration of organic solvents. The soluble enzyme, on the other hand, was rapidly inactivated even at fairly lower concentrations. The results suggest that the immobilization of watermelon urease in calcium alginate make it suitable for its application in organic media. The observations are discussed.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.05a
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• pp.158-162
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• 1995

Synergistic effects of mixed solvents, especially with mixtures of CS$_2$ with electron donor solvents, in inducing desired structural changes in coals were studied by solvent swelling techniques in addition to differential scanning calorimetric analyses. Mixed solvents exhibit significant synergistic efficacy in swelling the coal structure of medium bituminous rank. This synergy effect appears to be physical origin that is closely related to matching solubility parameters. Since the swollen coal structure can be obtained by mixed solvents with CS$_2$ at room temperature instead of high temperature, many possible technological pathways for economical utilization of coal might be sought.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.3
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• pp.147-150
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• 2004

Permeabilization is known to overcome cell membrane barriers of whole cell biocatalysts. The use of organic solvents is advantageous in terms of cost, simplicity, and efficiency. In this study, Ochrobactrum anthropi SY509 was permeabilized with various organic solvents. Treatment with organic solvents resulted in lower permeability barriers due to falling out lipids of the cell membrane. Therefore, permeabilized cells showed higher enzyme activity with no cell viability. Among various organic solvents, 0.5% (v/v) chloroform was selected as the most efficient permeabilizing reagent. Changes in the cell membrane structure were observe d and the residual amounts of phospholipids of the cell membrane were measured to investigate the mechanism of the improved permeability.

• Journal of Photoscience
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• v.11 no.3
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• pp.95-99
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• 2004

Optical absorption and emission studies have been carried out to understand the effect of deuterium on the solvent dependent photophysical properties of curcumin in deuterated solvents such as $CDCl_3,\;(CD_3)_2SO,\;(CD_3)_2CO,\;CD_3OD\;and\;CD_3CN$. Optical absorption spectral studies showed that there is no significant shift in absorption maxima compared to the non-deuterated solvent. The fluorescence maxima shows significant shift with polarity of solvent but not much affected by the deuteration. The fluorescence quantum yield of curcumin increased marginally in almost all the deuterated solvents, indicating reduction in the non-radiative pathways. The fluorescence decay was biexponential in all the solvents and the average fluorescence lifetime was not much affected with deuteration, but showed decrease with increasing solvent polarity. Based on these studies, it is concluded that intermolecular hydrogen transfer is only partially responsible for the excited state deactivation of curcumin.

• Toxicological Research
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• v.14 no.3
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• pp.329-332
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• 1998

Ingredients and concentrations of organic solvents in 7 kinds of adhesive sold on the domestic market were qualitatively and quantitatively analysed. Vapor concentrations were also analysed to estimate inhalation concentratins when adhesives were abused to get high. Acetone, methyl ethyl ketone, methyl cyclopenatane, cyclohexane and toluene were identified to be used in domstic adhesives as solvents. When organic solvents of adhesives were vaporized in the vial at the room temprature for 30 mins, concentrations of organic solvents in air were in the range of 5,000~140,000ppm. Among these solvents, toluene, known to have strong hallucination effect, showed 5,000~35,000 ppm. The putative concentration of toluene in case of glue sniffing was estimated to be about 5,000ppm in consideration of glue sniffing circumstances. Toluene was found in all adhesives in this study, even adhesives which toluene was not described in label.

• Fashion & Textile Research Journal
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• v.11 no.4
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• pp.672-677
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• 2009

To reduce the dependence of wool dyeing on the temperature several solvents with different properties and structures were added to the dye bath of C. I. Acid Yellow 42. Nearly the same total solubility parameters(${\delta}_t$) of solvents as those of wool fiber and hydrophobic part of the dyestuff were needed to increase disaggregation of dye molecules, loosening the wool fiber and wickabilty of dyeing solution; besides, the large surface tension(${\gamma}$) value of the solvents and the well balanced values of the three-component Hansen solubility parameters such as dispersion(${\delta}_d$), polar(${\delta}_p$), and hydrogen(${\delta}_h$) bonding parameters were required. Among the added solvents dimethyl phthalate(DMP) and acetophenone(AP) were satisfied with these conditions and worked the most successfully in the low temperature wool dyeing. Their effectiveness proven by the dyeing rate and the activation energy ($E_a$) of the dyeing was in the order of DMP > AP > DBE > CH > M >NONE. In conclusion the total solubility parameters(${\delta}_t$), the three-component Hansen parameters and the surface tension(${\gamma}$) of DMP and AP could be the guidelines to select suitable solvents for low temperature wool dyeing.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.246-251
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• 2009

The partitioning behavior of five printing ink solvents was studied in cookie ingredients and cookies to examine migration behavior, and to determine if one could predict Kp of a cookie from summing the Kp of each ingredient multiplied by its weight factor in the cookie formula. Solvents were ethyl acetate, hexane, isopropanol, methyl ethyl ketone, and toluene. Gas chromatography was used to measure Kp values on each raw and baked ($260^{\circ}C$ for 10 min) cookie ingredients, and lab-made cookies. The baking process-decreases in water content in each sample generally affected Kp of polar solvents, but did not affect that of the non-polar solvents. Structural changes in cookie ingredients during the baking process also caused some change of migration behavior. While the prediction of Kp of lab-made cookies using the Kp of raw ingredients showed significant differences between calculated and experimentally found values, predictions with baked ingredients showed much smaller differences. This suggests that loss of water and changes of crystallinity in cookies and cookie ingredients due to the baking process are important and affect the Kp.