Characterization of sol-gel bioencapsulates for ester hydrolysis and synthesis

• Published in: Applied biochemistry and biotechnology Vol. 121-124; no. 1-3; pp. 845 - 859
• Main Authors: Soares, Cleide M F, de Castro, Heizir F, Itako, Juliana E, de Moraes, Flavio F, Zanin, Gisella M
• Format: Journal Article
• Language: English
• Published: United States Springer Nature B.V 2005
• Subjects: 1-Butanol - chemistry; Biotechnology; Butanol; Butyric Acid - chemistry; Candida - enzymology; Candida rugosa; Coated Materials, Biocompatible - chemistry; Drug Storage; Enzyme Activation; Enzyme Stability; Enzymes; Enzymes, Immobilized - chemistry; Esterification; Esters; Gels - chemistry; Half-life; Hydrogen-Ion Concentration; Hydrolysis; Lipase - chemistry; Materials Testing; p-Nitrophenyl palmitate; Palmitic acid; pH effects; Phase Transition; Room temperature; Shelf life; Silanes - chemistry; Silica; Silica gel; Sol-gel processes; Storage stability; Studies; Synthesis; Temperature; Yeast
• ISSN: 0273-2289; 0273-2289; 1559-0291
• DOI: 10.1385/ABAB:123:1-3:0845

Candida rugosa lipase was entrapped in silica sol-gel particles prepared by hydrolysis of methyltrimethoxysilane and assayed by p-nitrophenyl palmitate hydrolysis, as a function of pH and temperature, giving pH optima of 7.8 (free enzyme) and 5.0-8.0 (immobilized enzyme). The optimum temperature for the immobilized enzyme (50-55 degrees C) was 19 degrees C higher than for the free enzyme. Thermal, operational, and storage stability were determined with n-butanol and butyric acid, giving at 45 degrees C a half-life 2.7 times greater for the immobilized enzyme; storage time was 21 d at room temperature. For ester synthesis, the optimum temperature was 47 degrees C, and high esterification conversions were obtained under repeated batch cycles (half-life of 138 h).