title: Efficient production of biodiesel from waste grease: one-pot esterification and transesterification with tandem lipases.
abstract: A novel concept and efficient method for producing biodiesel (FAME) from grease (15-40wt% free fatty acid, FFA) were developed by using tandem lipases for one-pot esterification of FFA and transesterification of triglyceride with methanol in a solvent-free system. Combining immobilized Candida antarctica lipase B (CALB) (Novozyme 435) favoring the esterification and immobilized Thermomyces lanuginosus lipase (TLL) (Lipozyme TLIM) preferring the transesterification at 2:8 (wt/wt) gave FAME in 80% yield, being better than that with Novozyme 435 or Lipozyme TLIM. Recombinant Escherichia coli (Calb/Tll) co-expressing CALB and TLL was engineered as a more efficient tandem-lipases system. Using wet or dry cells (4wt%) gave FAME in 87% or 95% yield, which is much better than that with E. coli cells expressing either CALB or TLL alone. Cells of E. coli (Calb/Tll) were recycled for five times and retained 75% productivity, thus being practical for producing biodiesel from grease.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117576, Singapore.
authors.forename: Jinyong
authors.initials: J
authors.lastname: Yan
authors.forename: Aitao
authors.initials: A
authors.lastname: Li
authors.forename: Yi
authors.initials: Y
authors.lastname: Xu
authors.forename: Thao P N
authors.initials: TP
authors.lastname: Ngo
authors.forename: Szechao
authors.initials: S
authors.lastname: Phua
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
mesh_terms: D001203:Ascomycota / Q000201:enzymology; D056804:Biofuels / Q000032:analysis*; D001709:Biotechnology / Q000379:methods*; D001711:Biotransformation; D002175:Candida / Q000201:enzymology; D004591:Electrophoresis, Polyacrylamide Gel; D004800:Enzymes, Immobilized / Q000378:metabolism; D004926:Escherichia coli / Q000166:cytology / Q000378:metabolism; D004951:Esterification; D004952:Esters / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D008049:Lipase / Q000378:metabolism*; D000432:Methanol / Q000378:metabolism; D009821:Oils / Q000378:metabolism*; D011995:Recombination, Genetic / Q000235:genetics; D059027:Recycling; D013997:Time Factors; D014866:Waste Products / Q000032:analysis*
chemical_list: D056804:Biofuels; D004800:Enzymes, Immobilized; D004952:Esters; D005227:Fatty Acids; D009821:Oils; D014866:Waste Products; D008049:Lipase; D000432:Methanol