title: Lipase immobilized on the hydrophobic polytetrafluoroethene membrane with nonwoven fabric and its application in intensifying synthesis of butyl oleate.
abstract: The synthesis of butyl oleate was studied in this paper with immobilized lipase. Five types of membrane were used as support to immobilize Rhizopus arrhizus lipase by following a procedure combining filtration and protein cross-linking. Results showed that hydrophobic polytetrafluoroethene membrane with nonwoven fabric (HO-PTFE-NF) was the favorite choice in terms of higher protein loading, activity, and specific activity of immobilized lipase. The factors including solvent polarity, lipase dosage, concentration, and molar ratio of substrate and temperature were found to have significant influence on conversion. Results showed that hexane (logP = 3.53) was a favorable solvent for the biosynthesis of butyl oleate in our studies. The optimal conditions were experimentally determined of 50 U immobilized lipase, molar ratio of oleic acid to butanol of 1.0, substrate concentration of 0.12 mol/L, temperature of 37 °C, and reaction time of 2 h. The conversion was beyond 91% and decreased slightly after 18 cycles. Lipase immobilization can improve the conversion and the repeated use of immobilized lipase relative to free lipase.
authors.affiliation: Beijing University of Chemical Technology, China.
authors.forename: Shu-Guang
authors.initials: SG
authors.lastname: Wang
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Zhang
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.forename: Zhong-Qi
authors.initials: ZQ
authors.lastname: Ren
authors.forename: Hong-Xia
authors.initials: HX
authors.lastname: Liu
mesh_terms: D055162:Biocatalysis; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005465:Fluorocarbon Polymers / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D008049:Lipase / Q000737:chemistry*; D008567:Membranes, Artificial; D009829:Oleic Acids / Q000737:chemistry*; D012233:Rhizopus / Q000737:chemistry / Q000201:enzymology; D013379:Substrate Specificity
chemical_list: D004800:Enzymes, Immobilized; D005465:Fluorocarbon Polymers; D005656:Fungal Proteins; D008567:Membranes, Artificial; D009829:Oleic Acids; C116457:1-butyl oleate; C010946:polytetrafluoroethane; D008049:Lipase