新型细菌细胞催化剂催化阿糖胞苷酰化反应的研究

1-β-D-Arabinofuranosylcytosine (ara-C) is a kind of unnatural nucleosides, which is used for the treatment of leukemias. However, it has some disadvantages in clinical use, such as poor lipophilicity, short half-life in human plasma, etc. An approach to resolving the problems is the preparation of its monoesters by acylation, which shows a higher bioactivity than ara-C itself. Whole-cell lipase regarded as naturally immobilized catalyst has advantages over commercial lipase since it can avoid the complicated isolation, purification, and immobilization processes which account for a large part in the lipase cost. Utilizing whole-cell lipase from Pseudomonas fluorescens can efficient synthesize 5’-O-acetyl 1-β-D-arabinofuranosylcytosine.The regioslectivity >92%. It was found that the optimal carbon source ,concentration of olive ,concentration of yeast extract were olive oil, 0.5%(w/v),0.3%(w/v).Under these culture conditions, the yield was 70.02% .