AbstractThe 11‐β hydroxylation of the steroid precursor Reichstein's substance S (cortexolone) to hydrocortisone byCurvularia lunatacells is used as a model system for investigating the basis of the effect of solvent choice on multiphase biotransformation reaction kinetics. The effect of solvent choice and phase ratio on cellular toxicity and productivity is examined in batch suspension cultures. In general, the greater the miscibility of the solvent with the aqueous phase, the more cellular toxicity it exhibits. However, the presence of solvent at concentrations above the solubility limit showed no increased toxic effect over that achieved with saturation concentrations. Toxicity experiments indicate that of the solvents examined octane is the least toxic to theCurvularia lunatasubstance S biotransformation system under consideration. The production of hydrocortisone is determined to be approximately 20 times greater during the growth phase than during the stationary phase. The phase ratio of the organic solvent added has a significant effect on the productivity of the system. It was found that there is an increase in productivity with an increase in the phase ratio of the organic solvent added. Reaction kinetics are examined, and the increase in productivity with increasing amounts of organic solvent is attributed to the increase in concentration of the steroid reactant in the syst
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机译:摘要将类固醇前体Reichstein物质S(皮质醇酮)11-β羟基化为氢化可的松,以研究溶剂选择对多相生物转化反应动力学影响的基础为研究对象。在分批悬浮培养物中检查溶剂选择和相比对细胞毒性和生产率的影响。一般来说,溶剂与水相的混溶性越大,它表现出的细胞毒性就越大。然而,与饱和浓度相比,浓度高于溶解极限的溶剂没有增加毒性作用。毒性实验表明,在所检查的溶剂中,辛烷值对正在考虑的 Curvularia lunatasubstance S 生物转化系统的毒性最小。氢化可的松的产生被确定为在生长期比在固定期高约20倍。添加的有机溶剂的相比对系统的生产率有显着影响。结果发现,随着所添加有机溶剂的相比的增加,生产率也随之提高。检查反应动力学,并且随着有机溶剂量的增加,生产率的提高归因于系统中类固醇反应物浓度的增加。
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