title: Immobilization of Pseudomonas stutzeri lipase for the transesterification of wood sterols with fatty acid esters.
abstract: Lipase from Pseudomonas stutzeri PL-836 was immobilized on hydrophobic supports and evaluated in the transesterification of wood sterols in solvent-free and solvent-containing media. Triton X-100 was used as additive during immobilization in butyl and octadecyl sepabeads increasing enzyme activity yield by 5% and 60%, respectively. Hyperactivation was observed during immobilization in EC octadecyl sepabeads with enzyme activity yield of 200% and protein immobilization yield of 93%. Thermostability of the immobilized enzyme was assessed at 50 °C in different media in the absence and presence of exogenous solvents. The presence of Triton X-100 during immobilization reduced enzyme stability while tert-butanol increased it. Transesterification in solvent-free and solvent-containing medium with lipase immobilized in EC octadecyl sepabeads showed that the presence of exogenous solvent increased both conversion yield and productivity. At rather high levels of biocatalyst hydration (40% on wet basis) the presence of tert-butanol in the reaction medium more than doubled conversion yield and productivity.
authors: School of Biochemical Engineering, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.
authors: Nicole
authors: N
authors: Fauré
authors: Andrés
authors: A
authors: Illanes
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D055162:Biocatalysis; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D004951:Esterification; D004952:Esters / Q000737:chemistry*; D005227:Fatty Acids / Q000737:chemistry*; D008049:Lipase / Q000737:chemistry* / Q000378:metabolism; D010840:Phytosterols / Q000737:chemistry*; D044223:Pseudomonas stutzeri / Q000737:chemistry / Q000201:enzymology*; D014934:Wood / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D004800:Enzymes, Immobilized; D004952:Esters; D005227:Fatty Acids; D010840:Phytosterols; D008049:Lipase