title: The solvent influence on the positional selectivity of Novozym 435 during 1,3-diolein synthesis by esterification.
abstract: The influence of solvents with a wide range of log P (from -0.23 to 4.5) on the positional selectivity of the immobilized lipase Novozym 435 during the esterification of oleic acid with glycerol for 1,3-diolein preparation was investigated. Analysis was performed on the basis of a simplified kinetic model of 1,3-diolein synthesis. The results showed that the preferential selectivity of Novozym 435 to 1-position over 2-position of the glycerol molecular became weaker and weaker with the increasing log P of the solvent. But after one 1-position was acylated, the preferential selectivity to the other 1-position over 2-position would be enhanced strongly for each solvent. The study also revealed that relatively hydrophilic solvent such as t-butanol was an ideal solvent for Novozym 435 catalyzed 1,3-diolein synthesis through esterification of oleic acid with glycerol.
authors.affiliation: Department of Chemical Engineering, Tsinghua University, Beijing 100084, PR China.
authors.forename: Zhang-Qun
authors.initials: ZQ
authors.lastname: Duan
authors.forename: Wei
authors.initials: W
authors.lastname: Du
authors.forename: De-Hua
authors.initials: DH
authors.lastname: Liu
mesh_terms: D004075:Diglycerides / Q000138:chemical synthesis* / Q000737:chemistry; D004800:Enzymes, Immobilized; D004951:Esterification; D005656:Fungal Proteins; D008049:Lipase / Q000378:metabolism*; D012997:Solvents / Q000737:chemistry*; D013379:Substrate Specificity
chemical_list: D004075:Diglycerides; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D012997:Solvents; C093667:Novozyme 435; D008049:Lipase; C089743:1,3-diolein