title: Enzymatic synthesizing of phytosterol oleic esters.
abstract: A method of synthesizing the phytosterol esters from oleic acid and sterols was studied, using immobilized lipase Candida sp. 99-125 as catalyst. Molar ratio (oleic acid/phytosterols), temperature, reaction period, organic solvents, catalyst, and silica-gel drier were optimized, and the result showed that 93.4% of the sterols had been esterified under the optimal synthetic condition: the molar ratio of oleic acid/phytosterol is 1:1 in 10 mL iso-octane, immobilized lipase (w, 140% of the sterols), incubated in an orbital shaker (200 rpm) at a temperature of 45 °C for 24 h. The immobilized lipase could be reused for at least 13 times with limited loss of esterification activity. The conversion still maintained up to 86.6%. Hence, this developed process for synthesizing phytosterol esters could be considered as simple and low-energy consumption compared to existing chemical processes.
authors.affiliation: College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Pan
authors.forename: Biqiang
authors.initials: B
authors.lastname: Chen
authors.forename: Juan
authors.initials: J
authors.lastname: Wang
authors.forename: Xinzhi
authors.initials: X
authors.lastname: Zhang
authors.forename: Biyun
authors.initials: B
authors.lastname: Zhul
authors.forename: Tianwei
authors.initials: T
authors.lastname: Tan
mesh_terms: D002175:Candida / Q000201:enzymology*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism; D004951:Esterification; D004952:Esters / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D008049:Lipase / Q000378:metabolism*; D009829:Oleic Acids / Q000138:chemical synthesis*; D010840:Phytosterols / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D058428:Silica Gel; D012997:Solvents; D013379:Substrate Specificity; D013696:Temperature; D013997:Time Factors
chemical_list: D004800:Enzymes, Immobilized; D004952:Esters; D009829:Oleic Acids; D010840:Phytosterols; D012997:Solvents; D058428:Silica Gel; D008049:Lipase