Study on enzymatic synthesis of methyl glucoside esters by lipase
| Autor: | Hen-Yi Ju, 朱恆儀 |
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| Rok vydání: | 2001 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 89 Sugar ester used in pharmaceutical, detergent, cosmetic, food industries. At present, sugar esters for chemical synthesis are commercially available. However, the process require high temperature and long time for chemical synthesis. It may cause lipids deterioration and unwanted products. Lipase synthesis sugar esters under mild reaction. In this study, 0.1 M methyl glucoside esterification in organic solvent with lauric acid. Effect of different reaction time ( 6-24 h ), temperature ( 30-50 ºC ), and methyl glucose to lauric acid molar ratio ( 1:2-1:6 ) on the acid incorporation ratio of methyl glucose ester, catalyzed by lipase AY, G, PS and IM77. Lipase catalyzed in organic system, but organic solvents and fatty acid attack to lipase which effected to inactive. If used immobilized lipase would not be effected. Acid incorporation of methyl glucoside esters effected to substrates molar ratio in this study. Immobilized lipase IM77 more activity and stable than the other lipase. Response surface methodology ( RSM ) and 5-level- 4-factor central composite rotatable design, CCRD were used to evaluate the effect of synthesis parameters, reaction time ( 4-20 h ), temperature ( 25-65 ºC ), methyl glucose to lauric acid molar ratio ( 1：2-1：6 ), and enzyme amount ( 10-50% ). Based on the ridge max analysis, optimum condition were：reaction time 8 h, temperature 44.5 ºC, substrate molar ratio 1：3.1, enzyme amount 15%, and acid incorporation ratio 2.48 ± 0.56 by lipase IM77. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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