• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.621-634
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• 2001

The characteristics of enzymatic methanolysis of castor oil were investigated as a clean technology. Among 16 lipases tested in this study, Novozym 435 showed the highest activity in methanolysis. Solvents had different effects on the methanolysis of castor oil according to weight percent (wt%) of Novozym 435. Heptane showed best activity with 1 wt% of Novozym 435, while isopropyl ether gave the best yield of ricinoleic acid methyl ester with 0.5 wt% of that. Ricinoleic acid methyl ester was obtained in 86% of yield through the methanolysis of castor oil catalyzed by Novozym 435 (1.0 wt%) during 24hr.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.562-565
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• 2002

The esterification reaction of previously obtained l,4-sorbitan with acrylic acid using Novozym 435 was carried out in t-butanol as solvent. Immobilized lipase Novozym 435 showed high enzymatic activity at $50^{\circ}C$ in t-butanol and optimum contents of Novozym 435 added in the esterification reaction was 3%(w/v). The maximum conversion rate was 55.8% when initial concentration was 50g/L and conversion rate of this reaction was 63.5% when the molar ratio of l,4-sorbitan to acrylic acid was 1:3.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.621-621
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• 2003

• KSBB Journal
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• v.18 no.3
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• pp.222-228
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• 2003

This study was performed to research a chemo-enzymatic synthesis of sorbitan acrylate. It w as firstly to determine the optimum conditions for D-sorbitol cyclic reaction in the presence of p-toluenesulfonic acid (p-TSA) as catalyst material. It was secondly to find the optimum conditions for sorbitan acrylate synthesis using immobilized lipase Novozym 435 in t-butanol from its materials. The maximum yield of 1,4-sorbitan synthesis were obtained approximately 90% (w/w) at 13$0^{\circ}C$ and 200 mmHg vacuum pressure with 1% (w/w) p-TSA after 150 min reactin time on our experimental system. The product from optimum condition was less color than those obtained at higher temperatures and minimized byproduct and unreacted D-sorbitol. Sorbitan acrylate was synthesized to around 63.5% conversion of 1,4-sorbitan. The experimental optimum condition was found at 5$0^{\circ}C$, atmospheric pressure, 3% (w/v) Novozym 435, 50 g/L 1,4-sorbitan of initial reactant concentration, and 1:3 molar ratio of 1,4-sorbitan to acrylic acid.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1183-1188
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• 2005

Several lipases of commercial grade were screened to catalyze the methanolysis of castor oil, and an immobilized Candida antarctica (Novozym 435) had the highest activity among the lipases tested. To enhance the yield of methyl ricinoleate, several reaction parameters were optimized. The optimum temperature was $50^{\circ}C$, and the original water content of lipase was sufficient to maintain the activity of lipase, and additional water supplied inhibited the methanolysis of castor oil. Because the lipase was deactivated by methanol, the reaction was tested by three-step addition of 1 molar equivalent of methanol to the oil. However, the oil was not completely converted to its methyl esters. The final reaction mixture using 3 molar equivalents of methanol to the oil consisted of $70\%$ methyl ricinoleate, $18\%$ monoricinoleate, $11\%$ diricinoleate, and trace triricinoleate at the equilibrium state. The yield of methyl ricinoleate was $97\%$ at 6 molar ratio of methanol to the oil with 300g of castor oil and 6g of immobilized Candida antarctica at $50^{\circ}C$ within 24 h.

• KSBB Journal
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• v.13 no.6
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• pp.706-717
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• 1998

Enzymatic synthesis of fructose-based sugar fatty acid esters, such as methyl fructoside oleic acid mono and diester, was investigated using methyl fructoside as a sugar starting material. For the production of methyl fructoside fatty acid monoester by solvent process, 2-methyl 2-propanol was found to be a god reaction medium resulting a higher yield and productivity due to its high sugar solubility. The yield and productivity of methyl fructoside oleic acid monoester were 70% and 12.6g/L-hr, respectively, when molar ratio of methyl fructoside, initial concentration of methyl fructoside, enzyme(Novozym 435) content, and reaction temperature were 3:1, 200g/L, 1%(w/v), and $60^{\circ}C$, respectively. Methyl fructoside oleic acid diester was prepared by lipase-catalyzed diacylation of methyl fructoside and oleic acid in the solvent-free process. Maximum yield of 98% and productivity of 140g/L-hr were achieved when molar ratio(methyl fructoside and oleic acid) of 1:2 enzyme content of 10%(w/v) and reaction temperature of $70^{\circ}C$ were applied for the operating conditions under a reduced pressure of 20∼200 mmHg.

• Journal of Life Science
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• v.23 no.10
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• pp.1246-1251
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• 2013

An organic solvent-tolerant lipase of Pseudomonas sp. BCNU 154 that was isolated from wastewater in the industrial complex region had optimal activity at $37^{\circ}C$ and pH 8. This crude extracellular lipase from BCNU 154 exhibited maximum stability in toluene, retaining about 6.01 U/ml (117.53%) activity for 2 h. $Ca^{2+}$, $Mg^{2+}$, $NH_4{^+}$, and $Na^+$ ions and triton X-100 activated the enzymes, whereas $Ba^{2+}$, $Hg^{2+}$, and $Zn^{2+}$ ions inhibited their activity. Pseudomonas sp. BCNU 154 lipase revealed stable activity comparable to that of the commercial immobilized Novozym 435. Thus, this organic solvent-tolerant lipase could have potential as a whole cell biocatalyst in industrial chemical processes without the use of immobilization.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.296-299
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• 2005

Sugar polymers have been considered as biomaterial. Biomaterials are widely utilized for a medical applications in direct contact with living tissue Clearly, biomaterials must be carefully and microscopically fabricated for optimal acceptance within the living organism in both functional and structural senses. In this study, the enzymatic synthesis of sorbitan methacrylate from 1,4-sorbitan via the manipulation of an immobilized biocatalyst (Novozym 435) and acryl donors (methacrylic acid and vinyl methacrylate) was evaluated.

• Journal of the Korean Applied Science and Technology
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• v.20 no.3
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• pp.251-258
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• 2003

Biodiesel as methyl esters derived from vegetable oils has considerable advantages in terms of environmental protetion. In the present work, methyl esters were produced from soybean oil by lipase-catalyzed transesterification. To reduce inactivation of commercial immobilized lipases emulsified two-step process was developed using the stepwise addition of methanol with 4:1 molar ratio at 4h intervals. Also with immobilized lipase from Candida antarctica(Novozym 435) high conversion of 98.5 percent was possible at $45^{\circ}C$ of reaction temperature with 4:1 of methanol-to-oil molar ratio and 1%(v/v) methyl glucoside oleic polyester as an emulsifier in the presence of cosolvent.

• Journal of the Korean Applied Science and Technology
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• v.21 no.1
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• pp.37-44
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• 2004

Glycosyl acrylate and methacrylate were synthesized by lipase-catalyzed esterification of vinyl acrylate and vinyl methacrylate with ${\beta}$-methyl glucoside in t-butanol as a reaction medium. At the optimum conditions of initial concentration of 150g/l ${\beta}$-methyl glucoside, molar ratio of 1 : 3, 5%(w/v) lipase(Novozym 435) and $50^{\circ}C$, we attained up to 100% conversion for enzymatic glycosylation of vinyl acrylate and vinyl methacrylate by supersaturated solvent process. The polymerizable glycosyl acrylates and methacrylate are expected to have biomedical application as hydrophilic monomers and hydration modifiers to be used for biocdmpatible hydrogel.