Optically active (R)-a-monobenzoyl glycerol (MBG) was synthesized by Candida antarctica lipase B (CHIRAZYMET L-2) catalyzed asymmetric esterification of glycerol with benzoic anhydride in organic solvents. Various conditions, such as the type and composition of the organic solvent, water content of the system, reaction temperature, and concentrations of the substrates were systematically examined and optimized in screw-capped test tubes with respect to both the reaction rate and the enzyme selectivity. 1,4-Dioxane was found to be the best solvent and no additional water was needed for the system. The optimum temperature was around 30℃, while the most suitable substrate concentrations were 100mM each for glycerol and benzoic anhydride, respectively. However, when excessive anhydride (e.g., 200mM) was used, the produced MBG could be further transformed into 1,3-dibenzoyl glycerol (DBG) by the same enzyme with a priority to (S)-MBG, resulting in a significant improvement of the product optical purity from ca. 50-70% e.e. Under optimal conditions (100mM glycerol, 100-200mM benzoic anhydride, dioxane, 25-30℃), the enzymatic synthesis of (R)-MBG was successfully operated in a packed-bed reactor for about 1 week, with an average productivity of 0.79g MBG/day/g biocatalyst in the case of continuous operation and 0.94g MBG/day/g biocatalyst in the case of semicontinuous operation. After refinement and preferential crystallization of the crude product, (R)-MBG could be obtained in an almost optically pure form (>98% e.e.).

Lipase production and cell growth of Serratia marcescens ECU1010 were optimized in shake flasks, with lipase production being enhanced 9.5-fold (4,780 U/l) compared with the initial activity (500 U/l). Optimal carbon and nitrogen sources were Tween-80 and peptone, and the optimal ratio of Tween-80 to peptone was 1:3. The optimized cultivation conditions were 25[1]C and pH 6.5. Lipase activity, particularly specific activity, could be improved by decreasing the cultivation temperature from 35 to 25[1]C. Enzyme stability was significantly improved by simple immobilization with synthetic adsorption resin no. 8244. After five reaction cycles, enzyme activity decreased only very slightly, while enantioselectivity of the preparation remained constant, and the ees (enantiomeric excess of the remaining substrate) achieved in all cases was higher than 97%. The resin-8244-lipase preparation can be used for efficient enantioselective hydrolysis of trans-3-(4

A bacterial strain (ECU1001) capable of utilizing phenyl glycidyl ether as sole carbon source and energy source was isolated from soil samples through two steps of screening and was identified as a Bacillus megaterium. The epoxide hydrolase from Bacillus megaterium ECU1001 was biosynthesized in parallel with cell growth and a maximum activity of 31.0 U/l was reached after 30h of culture when the biomass (DCW) was 9.1g/l. A temperature of 35◦C and pH 8.0 were optimal for the bioconversion. The lyophilized whole cells of Bacillus megaterium ECU1001 could preferentially hydrolyze the (R)-enantiomer of phenyl glycidyl ether, yeilding (S)-epoxide and (R)-diol with high enantioselectivity (E=47.8). The (S)-enantiomer of the epoxide remained in the reaction mixture with >99.5% ee (enantiomeric excess) at a conversion of 55.9%. The substrate concentration could be increased up to 60mM without affecting the ee and (S)-phenyl glycidyl ether could be obtained with an optical purity of 100% ee and 25.6% yield. Therefore, the method is potentially useful for the preparative resolution of epoxides.

The optimal activity of a Candida rugosa lipase (Lipase OF) for hydrolysis of 2-chloroethyl ester of Ketoprofen [2-(3-benzoyphenyl) propionic acid] was at pH 4.0, while the best enantioselectivity (E) was at pH 2.2 where the enzyme was still 60% active and stable.

.1%, was sufficient to fully express the catalytic activity of the surfactant-modified enzyme since introduction of additional water led to a sharp decrease in enzyme activity. When the substrate (HMPC) concentration was as high as 1M, the reaction reached 40% conversion in 20h with merely 1.0mg ml−1 of the DGG-lipase, producing (R)-HMPC acetate in nearly 100% ee.