Refining androstenedione and bisnorcholenaldehyde from mother liquor of phytosterol fermentation using macroporous resin column chromatography followed by crystallization.

Androstenedione is an androgen and intermediate in the biosynthesis of most adrenocortical, anabolic, sex and synthetic steroids, such as canrenone, eplerenone, norethindrone and spironolactone. Bisnorcholenaldehyde is an important intermediate in the synthesis of progesterone. This study established an androstenedione and bisnorcholenaldehyde separation method that used a macroporous adsorption resin and an ethanol-water mixture as eluent. The adsorption properties of 12 non-polar or weakly polar macroporous adsorption resins were compared, and three resins exhibited a high adsorption capacity and high desorption rate for both androstenedione and bisnorcholenaldehyde. The three resins were then compared using column chromatography, and one resin was selected and parameters (flow rate, resin size, ethanol concentration and volume) of chromatography were optimized to obtain high purity and recovery. Chromatography eluate was concentrated, dissolved in suitable solvent and crystallized at an optimal temperature to obtain a high purity of both androstenedione and bisnorcholenaldehyde from the same starting material. The levels of androstenedione and bisnorcholenaldehyde in the raw material were 39.78% and 19.15%, respectively. After preparative separation and enrichment by resin column chromatography and crystallization, the purity of androstenedione and bisnorcholenaldehyde was 94.3% and 98.6%, respectively, with their recovery yields of 66.8% and 57.9%, respectively. In addition, the resin maintained over 90% separation efficiency for 5 cycles of adsorption. These results indicated that the combination of macroporous resin chromatography followed by crystallization provide a simple, effective, environmentally friendly and low-cost method for the simultaneous purification of androstenedione and bisnorcholenaldehyde.

Optimization of Serratia marcescens lipase production for enantioselective hydrolysis of 3-phenylglycidic acid ester.

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 degrees C and pH 6.5. Lipase activity, particularly specific activity, could be improved by decreasing the cultivation temperature from 35 to 25 degrees 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'-methoxyphenyl)glycidic acid methyl ester [(+/-)-MPGM], a key intermediate in the synthesis of Diltiazem.