摘要
初步研究赭曲霉NG0 2 16固定化细胞的催化转化坎利酮11α羟基化的条件。实验表明优化的固定化方法为:4 %的海藻酸钠包埋15 %的湿菌体,在4 %的氯化钙溶液中固化1h。催化转化条件为:8g/L坎利酮,pH 6 0 ,2 8℃。连续转化3批,每批的转化率均超过85 %。转化获得的羟基化坎利酮粗品经乙酸乙酯提取分离,三次重结晶后,采用质谱、核磁共振、元素分析等手段对羟基化坎利酮进行结构表征。鉴定结果表明,得到结晶的羟基化坎利酮含量为99 7% ,结晶呈浅黄色针状,其表面光滑;结构表征结果确认所制备的物质为11α羟基化坎利酮,其熔点为2 4 0℃,在乙酸乙酯中的比旋光度为 12 8°。
Bio-transformational 11α-hydroxylation of canrenone has been studied by using immobilized whole cells of Aspergillus ochraceus NG0216. It was showed that the optimal immobilization process was that the wet cells with mass concentration 15% was immobilized by 3% sodium alginate and solidified by 4% calcium chloride for 1 h. Optimal mass concentration of canrenone was 10 g/L. Optimal pH and temperature were 6.0 and 28℃. The conversation rtae of 11α-hydroxylating rate of canrenone exceeded 85 % by the above immobilized cells under the optimal conditions. After solid-liquid separation and extract by ethyl acetate the crude hydroxycanrenone was obtained and purified by re-crystallization. Structural characterization of purified hydroxycanrenone was conducted by means of MS, NMR, and element assay. Result of HPLC showed that content of hydroxycanrenone of purified crystals was up to 99.7% through thrice re-crystallization in ethyl acetate. The purified crystals appeared canary acicular. It was proved that the product of bio-catalyzed oxidation by immobilized whole cells was 11α-hydroxycanrenone, its melting point was 240 ℃, and its [ α]^20D in ethyl acetate is - 12. 825°.
出处
《生物加工过程》
CAS
CSCD
2005年第2期45-49,共5页
Chinese Journal of Bioprocess Engineering
作者简介
茅燕勇（1977-），男，硕士生，主要从事酶催化不对称合成方面的研究。
联系人：范伟平，025-83587339，Fwpzhu@sohu.com
