title: Immobilization of lipase B from Candida antarctica on porous styrene-divinylbenzene beads improves butyl acetate synthesis.
abstract: A new biocatalyst of lipase B from Candida antarctica (MCI-CALB) immobilized on styrene-divinylbenzene beads (MCI GEL CHP20P) was compared with the commercial Novozym 435 (immobilized lipase) in terms of their performances as biocatalysts for the esterification of acetic acid and n-butanol. The effects of experimental conditions on reaction rates differed for each biocatalyst, showing different optimal values for water content, temperature, and substrate molar ratio. MCI-CALB could be used at higher acid concentrations, up to 0.5 M, while Novozym 435 became inactivated at these acid concentrations. Although Novozym 435 exhibited 30% higher initial activity than MCI-CALB for the butyl acetate synthesis, the reaction course was much more linear using the new preparation, meaning that the MCI-CALB allows for higher productivities per cycle. Both preparations produced around 90% of yield conversions after only 2 h of reaction, using 10% (mass fraction) of enzyme. However, the main advantage of the new biocatalyst was the superior performance during reuse. While Novozym 435 was fully inactivated after only two batches, MCI-CALB could be reused for six consecutive cycles without any washings and keeping around 70% of its initial activity. It is proposed that this effect is due to the higher hydrophobicity of the new support, which does not retain water or acid in the enzyme environment. MCI-CALB has shown to be a very promising biocatalyst for the esterification of small-molecule acids and alcohols.
authors.affiliation: Biocatalysis and Enzyme Technology Lab, Institute of Food Science and Technology, Federal University of Rio Grande do Sul State, Av. Bento Gonçalves, ZC 91501-970, Porto Alegre, RS, Brazil.
authors.forename: Natália G
authors.initials: NG
authors.lastname: Graebin
authors.forename: Andréa B
authors.initials: AB
authors.lastname: Martins
authors.forename: André S G
authors.initials: AS
authors.lastname: Lorenzoni
authors.forename: Cristina
authors.initials: C
authors.lastname: Garcia-Galan
authors.forename: Roberto
authors.initials: R
authors.lastname: Fernandez-Lafuente
authors.forename: Marco A Z
authors.initials: MA
authors.lastname: Ayub
authors.forename: Rafael C
authors.initials: RC
authors.lastname: Rodrigues
mesh_terms: D020001:1-Butanol / Q000378:metabolism; D000085:Acetates / Q000737:chemistry / Q000378:metabolism*; D055162:Biocatalysis; D002175:Candida / Q000737:chemistry / Q000201:enzymology*; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D004951:Esterification; D007700:Kinetics; D008049:Lipase / Q000737:chemistry / Q000378:metabolism*; D016062:Porosity; D020058:Styrene / Q000737:chemistry; D014753:Vinyl Compounds / Q000737:chemistry
chemical_list: D000085:Acetates; D004800:Enzymes, Immobilized; D014753:Vinyl Compounds; D020058:Styrene; C006848:butyl acetate; D020001:1-Butanol; D008049:Lipase; C004985:divinyl benzene