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采用琼脂扩散法、糖代谢活力保留法和细胞生长抑制试验评价了6种离子液体对热带假丝酵母104细胞的毒性大小,以期构建可用于热带假丝酵母细胞催化3,5-双三氟甲基苯乙酮不对称还原的含离子液体反应体系.研究表明:离子液体[EMIM](L)-Lac对热带假丝酵母细胞的毒性最小,在含该离子液体的体系中进行不对称还原时可获得最高产率.阴离子为(L)-Lac-的离子液体对细胞的毒性较BF4-的低;且阴离子为BF4-时,离子液体对细胞的毒性随阳离子咪唑环上烷基侧链取代基长度的增加而增加.与基于细胞生长抑制试验获得的离子液体EC50值的毒性评价相比较,采用琼脂扩散法和糖代谢活力保留法均可快速、简便地检测离子液体的生物相容性,后两种方法可为快速筛选合适的离子液体种类,以构建含离子液体反应体系提供一定的依据. 相似文献
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(S)-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of (S)-3,5-bistrifluoromethylphenyl ethanol was successfully performed in high enantiomeric excess (e.e.) through asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone catalyzed by Candida tropicalis 104 cells. The influence of some key reaction parameters such as substrate concentration, co-substrate and its concentration, biomass and reaction time was examined, respectively. The results showed that these factors obviously influence the yield, but the optical purity of the prepared product remains intact. The opti-mum conditions for the preparation of (S)-3,5-bistrifluoromethylphenyl ethanol were found to be as follows: sub-strate concentration 50 mmol?L?1; 50 g·L-1 of maltose as co-substrate; wet cell concentration 300 g·L-1; reaction for 30 h. Under above optimal conditions, the maximum yield for (S)-3,5-bistrifluoromethylphenyl ethanol reached 70.3% with 100% of product e.e. 相似文献