Small water amounts increase the catalytic behaviour of polar organic solvents pre-treated Candida rugosa lipase

Following a simple and quick treatment based on dissolving the crude lipase of Candida rugosa in different percentages (v/v) of several polar organic solvents (methanol, ethanol, acetone, l-propanol, 2-propanol, l-butanol and 2-butanol), and a further dialysis, different preparations with enhanced activity and thermal stability were obtained. This improved catalytic behaviour was observed in aqueous media (more efficient triglyceride hydrolysis) as well as in anhydrous organic solvents (better enantioselectivity and/or yield in the esterification of R- and S-ketoprofen). Combination of this treatment with organic solvents with a correct control of water activity in the reaction media allowed a much better catalytic behaviour, dramatically increasing the reaction yield and the enantiodiscrimination ability in the esterification of S-ketoprofen vs. the R counterpart. (C) 2001 Elsevier Science B.V. All rights reserved.