title: Combined utilization of lipase-displaying Pichia pastoris whole-cell biocatalysts to improve biodiesel production in co-solvent media.
abstract: Lipase-displaying whole cells appear to be efficient biocatalysts because of their low preparation costs and simple recycling procedure. The combined utilization of Candida antarctica lipase B (CALB) and Rhizomucor miehei lipase (RML), separately displayed on Pichia pastoris whole cells, to produce biodiesel in co-solvent media was investigated. A response surface methodology incorporating a D-optimal design was employed to obtain the optimum reaction conditions for methyl ester (ME) synthesis. The synergistic effect of the two displayed lipases and the use of tert-butanol and isooctane as the co-solvent media were found to significantly improve the transesterification reaction. Scaled-up reactions using various types of feedstock were carried out in a 0.5-l stirred reactor under optimum conditions, affording ME yields over 90% in 12h. Moreover, the ME yields remained above 85% after 20 repeated batch cycles. In conclusion, this biocatalyst affords a promising route to efficient biodiesel production.
authors.affiliation: Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, PR China.
authors.forename: Zi
authors.initials: Z
authors.lastname: Jin
authors.forename: Shuang-Yan
authors.initials: SY
authors.lastname: Han
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Sui-Ping
authors.initials: SP
authors.lastname: Zheng
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Lin
mesh_terms: D000704:Analysis of Variance; D056804:Biofuels; D019149:Bioreactors; D002175:Candida / Q000201:enzymology*; D002384:Catalysis; D005656:Fungal Proteins / Q000378:metabolism*; D008049:Lipase / Q000378:metabolism*; D010843:Pichia / Q000378:metabolism*; D010938:Plant Oils / Q000378:metabolism; D020103:Rhizomucor / Q000201:enzymology*
chemical_list: D056804:Biofuels; D005656:Fungal Proteins; D010938:Plant Oils; D008049:Lipase; C431349:lipase B, Candida antarctica