微生物转化连翘苷制备连翘脂素的研究

本文旨在开发一种微生物转化工艺,将连翘苷转化为活性更高的连翘脂素.结果从土壤中分离筛选到一株桔青霉(Penicillium citrinum)LB菌株,转化连翘苷为连翘脂素的专一性较高.经培养基主要组成和转化条件优化,得出较佳的产酶培养组成为:蔗糖7 g/L,(NH4)2 SO45 g/L,NaCl 5 g/L,KH2 PO45 g/L,MgSO41 g/L,MnSO40.5 g/L,pH 6.0.LB菌株经产酶培养后,过滤收集菌体悬浮于2倍发酵液体积的磷酸盐缓冲液中,加入2 g/L的底物连翘苷,于30℃、200 r/min转化20 h,连翘脂素的转化得率可达94.1%.利用微生物将连翘苷转化为连翘脂素,具有方法简单、转化得率高、产物容易纯化和副产物少等优点,有潜在的工业化应用价值.

Production of phillygenin from phillyrin by microbial bioconversion

A bioconversion process was developed for production of phillygenin from its glycosidic form—phillyrin. A strain of Penicillium citrinum designated as LB was isolated from the soil, which could specifically produce enzyme for bioconversion of phillyrin to phillygenin. After main composition for LB strain producing enzyme and bioconversion conditions were optimized, a high molar yield of phillygenin could be obtained. The optimized medium contained sucrose 7 g/L, (NH4)2SO45 g/L, NaCl 5 g/L, KH2PO45 g/L, MgSO41 g/L, MnSO40. 5 g/L, with pH 6. 0. After the strain LB was cultivated in enzyme-producing medium for 2 days, the cells were harvested by filtration and suspended in pH 6. 0 phosphate buffer at the volume of 2 times of the culture. 2 g/L of phillyrin was added in the cell suspension, and the bioconversion was carried out at 30 ℃, 200 r/min for 20 h. The molar yield of phillygenin could reach 94. 1%. The developed process had advantages of simple operation, high productivity, convenience for product purification and less by-products, which might be a potential way for production of phillygenin in the pharmaceutical industry.