title: Production of flavor esters catalyzed by CALB-displaying Pichia pastoris whole-cells in a batch reactor.
abstract: Candida antarctica lipase B (CALB) has been employed as an efficient catalyst in the preparation of many flavor esters. A CALB-displaying yeast whole-cell biocatalyst could be an attractive alternative to commercial immobilized CALB because of its low-cost preparation and high enzymatic activity. We investigated the potential application of CALB-displaying Pichia pastoris cells for the production of flavor esters. The optimal conditions for flavor esters synthesis by this biocatalyst were determined in 50-ml shake flasks. Under optimized conditions, the synthesis of 12 kinds flavor esters were scaled up in a 5-l batch stirred reactor. Among these, the mole conversions of 10 exceeded 95% after reactions for 4h. In addition, this biocatalyst showed good tolerance for high substrates concentration and excellent operational stability. Repeated use of the cells in 10 batches resulted in an activity loss of less than 10%. Thus, CALB-displaying P. pastoris whole cells are robust biocatalysts with potential commercial application in the large-scale production of flavor esters in non-aqueous media.
authors.affiliation: Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology, Guangzhou, PR China. 13760601940@126.com
authors.forename: Zi
authors.initials: Z
authors.lastname: Jin
authors.forename: Janvier
authors.initials: J
authors.lastname: Ntwali
authors.forename: Shuang-Yan
authors.initials: SY
authors.lastname: Han
authors.forename: Sui-Ping
authors.initials: SP
authors.lastname: Zheng
authors.forename: Ying
authors.initials: Y
authors.lastname: Lin
mesh_terms: D000085:Acetates / Q000032:analysis / Q000378:metabolism; D019342:Acetic Acid; D019149:Bioreactors / Q000382:microbiology*; D001709:Biotechnology / Q000295:instrumentation; D004800:Enzymes, Immobilized; D004867:Equipment Design; D004952:Esters / Q000032:analysis / Q000378:metabolism*; D005421:Flavoring Agents / Q000032:analysis / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D008049:Lipase / Q000378:metabolism*; D000439:Pentanols / Q000032:analysis / Q000378:metabolism; D010843:Pichia / Q000378:metabolism*
chemical_list: D000085:Acetates; D004800:Enzymes, Immobilized; D004952:Esters; D005421:Flavoring Agents; D005656:Fungal Proteins; D000439:Pentanols; C425828:3-hexenylacetate; C093667:Novozyme 435; D008049:Lipase; C431349:lipase B, Candida antarctica; D019342:Acetic Acid; C020377:isoamyl acetate