title: Biocatalytic methanolysis activities of cross-linked protein-coated microcrystalline lipase toward esterification/transesterification of relevant palm products.
abstract: Biocatalysis by immobilized lipase is an efficient alternative process for conversion of crude vegetable oil with high free fatty acid content to biodiesel, which is the limit of the conventional alkaline-catalyzed reaction. In this study, influences of solid-state organic and inorganic buffer core matrices with different pKa on catalytic performance of cross-linked protein coated microcrystalline biocatalysts prepared from Thermomyces lanuginosus lipase (CL-PCMC-LIP) toward esterification of palmitic acid (PA), transesterification of refined palm oil (RPO), and co-ester/transesterification of crude palm oil (CPO) to fatty acid methyl ester (FAME) was studied. Glycine, CAPSO (3-(cyclohexylamino)-2-hydroxy-1-propanesulfonic acid), and TAPS ([(2-hydroxy-1,1-bis(hydroxymethyl)ethyl)amino]-1-propanesulfonic acid) were shown to be potent core matrices for these reactions. The optimal reaction contained 4:1 [methanol]/[fatty acid] molar equivalence ratio with 20% (w/w) CL-PCMC-LIP on glycine in the presence of tert-butanol as a co-solvent. Deactivation effect of glycerol on the biocatalyst reactive surface was shown by FTIR, which could be alleviated by increasing co-solvent content. The maximal FAME yields from PA, RPO, and CPO reached 97.6, 94.9, and 95.5%, respectively on a molar basis under the optimum conditions after incubation at 50°C for 6h. The biocatalyst retained >80% activity after recycling in five consecutive batches. The work demonstrates the potential of CL-PCMC-LIP on one-step conversion of inexpensive crude fatty acid-rich feedstock to biodiesel.
authors: Joint Graduate School for Energy and Environment (JGSEE), King Mongkut's University of Technology Thonburi, Bangmod, Bangkok 10140, Thailand.
authors: Marisa
authors: M
authors: Raita
authors: Joint Graduate School for Energy and Environment (JGSEE), King Mongkut's University of Technology Thonburi, Bangmod, Bangkok 10140, Thailand.
authors: Navadol
authors: N
authors: Laosiripojana
authors: Enzyme Technology Laboratory, National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand. Electronic address: verawat@biotec.or.th.
authors: Verawat
authors: V
authors: Champreda
mesh_terms: D001203:Ascomycota / Q000201:enzymology; D056804:Biofuels; D001709:Biotechnology; D002384:Catalysis; D003432:Cross-Linking Reagents; D003460:Crystallization; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D004951:Esterification; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism; D008049:Lipase / Q000737:chemistry / Q000378:metabolism*; D000432:Methanol / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D000073878:Palm Oil; D010938:Plant Oils / Q000737:chemistry / Q000378:metabolism*
chemical_list: D056804:Biofuels; D003432:Cross-Linking Reagents; D004800:Enzymes, Immobilized; D005227:Fatty Acids; D005656:Fungal Proteins; D010938:Plant Oils; D000073878:Palm Oil; D008049:Lipase; D000432:Methanol
keywords: Biodiesel; Cross-linked protein coated microcrystal; Esterification; Lipase; Transesterification