title: A robust whole-cell biocatalyst that introduces a thermo- and solvent-tolerant lipase into Aspergillus oryzae cells: characterization and application to enzymatic biodiesel production.
abstract: To develop a robust whole-cell biocatalyst that works well at moderately high temperature (40-50°C) with organic solvents, a thermostable lipase from Geobacillus thermocatenulatus (BTL2) was introduced into an Aspergillus oryzae whole-cell biocatalyst. The lipase-hydrolytic activity of the immobilized A. oryzae (r-BTL) was highest at 50°C and was maintained even after an incubation of 24-h at 60°C. In addition, r-BTL was highly tolerant to 30% (v/v) organic solvents (dimethyl carbonate, ethanol, methanol, 2-propanol or acetone). The attractive characteristics of r-BTL also worked efficiently on palm oil methanolysis, resulting in a nearly 100% conversion at elevated temperature from 40 to 50°C. Moreover, r-BTL catalyzed methanolysis at a high methanol concentration without a significant loss of lipase activity. In particular, when 2 molar equivalents of methanol were added 2 times, a methyl ester content of more than 90% was achieved; the yield was higher than those of conventional whole-cell biocatalyst and commercial Candida antarctica lipase (Novozym 435). On the basis of the results regarding the excellent lipase characteristics and efficient biodiesel production, the developed whole-cell biocatalyst would be a promising biocatalyst in a broad range of applications including biodiesel production.
authors.affiliation: Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Adachi
authors.forename: FookHee
authors.initials: F
authors.lastname: Koh
authors.forename: Shinji
authors.initials: S
authors.lastname: Hama
authors.forename: Chiaki
authors.initials: C
authors.lastname: Ogino
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kondo
mesh_terms: D001236:Aspergillus oryzae / Q000166:cytology / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins; D001674:Bioelectric Energy Sources; D056804:Biofuels; D001709:Biotechnology / Q000379:methods; D018914:Cells, Immobilized; D002849:Chromatography, Gas; D004795:Enzyme Stability; D056506:Geobacillus / Q000145:classification / Q000201:enzymology / Q000235:genetics; D008049:Lipase / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D000432:Methanol / Q000378:metabolism / Q000494:pharmacology*; D000073878:Palm Oil; D010938:Plant Oils / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D012997:Solvents / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D001426:Bacterial Proteins; D056804:Biofuels; D010938:Plant Oils; D011994:Recombinant Proteins; D012997:Solvents; D000073878:Palm Oil; D008049:Lipase; C428386:thermostable lipase; D000432:Methanol