title: A highly regioselective route to arbutin esters by immobilized lipase from Penicillium expansum.
abstract: Immobilized lipase from Penicillium expansum, a novel and inexpensive enzyme preparation that we immobilized in our laboratory, was an excellent catalyst for highly regioselective acylation of arbutin with fatty acid vinyl esters. For the enzymatic butanoylation of arbutin, under the optimal conditions, initial reaction rate was 75.1 mM/h, and substrate conversion and regioselectivity were greater than 99%. In addition, a variety of 6'-esters of arbutin were prepared with high conversion (>99%) and excellent regioselectivity (>99%). It was found that the enzymatic reaction rate varied widely with different acyl donors, presumably owing to their different interactions with the active site of the lipase. The immobilized lipase from P. expansum displayed highest catalytic activity with medium-length straight-chain acyl donors. Acyl donors bearing a substituent or a conjugate double bond gave reduced reaction rates.
authors.affiliation: State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
authors.forename: Rong-Ling
authors.initials: RL
authors.lastname: Yang
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Ri-Feng
authors.initials: RF
authors.lastname: Li
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Smith
authors.forename: Min-Hua
authors.initials: MH
authors.lastname: Zong
mesh_terms: D000215:Acylation; D001104:Arbutin / Q000138:chemical synthesis*; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D004951:Esterification; D005227:Fatty Acids / Q000737:chemistry*; D008049:Lipase / Q000737:chemistry*; D010084:Oxidation-Reduction; D010407:Penicillium / Q000145:classification* / Q000201:enzymology*; D013045:Species Specificity
chemical_list: D004800:Enzymes, Immobilized; D005227:Fatty Acids; D001104:Arbutin; D008049:Lipase