CLEAs of Candida antarctica lipase B (CALB) with a bovine serum albumin (BSA) cofeeder core. Study of their catalytic activity

M.P. GUAUQUE TORRES; M. L. FORESTI; M.L. FERREIRA

BIOCHEMICAL ENGINEERING JOURNAL

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2014 vol. 90 p. 36 - 43

1369-703X

Highly active CALB cross-linked enzyme aggregates (CLEAs) were synthesized using a layered methodologybased on the synthesis of a cross-linked protein cofeeder core over which an external layer of lipasewas later cross-linked. The layered CALB CLEAs were characterized in terms of their catalytic activity inthree different test reactions: esterification of oleic acid and ethanol in absence of solvents, esterificationof oleic acid and heptanol in organic medium, and hydrolysis of triolein in emulsioned medium. Theimpact of the cross-linker/protein mass ratio on CLEAs activity, and its evolution with storage time wereevaluated in the solventless synthesis of ethyloleate. The amount of cross-linker used showed to be a keyparameter for the evolution of the catalytic activity of CLEAs during storage. Under the best conditionsfound, hyperactivated CALB CLEAs with up to 188% of recovered activity in ethyl oleate synthesis wereobtained. In terms of hydrolytic activity mature layered CALB CLEAs showed a retained activity of 68%.The assay of dried mature layered CALB CLEAs in heptyl oleate synthesis showed catalytic activities muchhigher than the one exhibited by free CALB, reaching 1 h-fatty acid conversions of 14% and 2%, respectively.The high catalytic activity shown by layered CALB CLEAs, suggests that they are an interestingalternative specially for the catalysis of fatty acid esterifications in both organic and solventless medium.