Abstract
This paper shows that the properties of lipase B from
Candida antarctica (CAL-B) may be easily modulated using different hydrophobic supports to immobilize it (octyl and butyl-agarose, octadecyl-Sepabeads or Lewatit). CAL-B could be fully desorbed from the supports by just incubating the biocatalyst with Triton X-100, although the concentration of detergent necessary was to fully desorb the enzyme varied with the support employed (from 1% for butyl-agarose to 4% for octadecyl-Sepabeads), suggesting that in all cases, the main reason for the enzyme immobilization was hydrophobic interactions. Lewatit VP OC 1600 yielded very different results in terms of activity, selectivity or enantioselectivity in the hydrolysis of rac-2-
O-butyryl-2-phenylacetic acid (
1) and 3-phenylglutaric acid dimethyl diester (
3) compared to the other preparations. For example, in the hydrolysis of
1, Novozym 435 preferred the S-isomer (with an
E value higher than 100) whereas all the other preparations preferred the R isomer (e.g. octyl-agarose-CAL-B with
E value of 50). In the hydrolysis of
3, Novozym 435 gave S-3-phenylglutaric acid methyl ester with an ee higher than 99%, by coupling the first asymmetric hydrolysis to the enantiospecific hydrolysis of the monoester. CAL-B immobilized on Lewatit at low ionic strength not only behaved similarly to Novozym 435, but also presented some differences that should be due to the exact protocol of the enzyme immobilization in Novozym 435.