羟基脂肪酸生产菌Bacillus pumilus对油酸的代谢特性和产物分析

Metabolic Characteristic and Product Analysis for Bioconversion of Oleic Acid by Bacillus pumilus

一株具有转化油酸羟基化的微生物Bacillus pum ilus BD-12(记作BP BD-12),在摇瓶条件下分批深层培养,研究了菌株在以胰蛋白胨为主要氮源、葡萄糖为基本碳源的条件下对油酸(OA)的代谢特性,并对转化OA生成羟基脂肪酸的规律及产物进行了分析测定。结果表明:在只有葡萄糖作碳源条件下,细胞生长良好,且无羟基脂肪酸生成,OA对菌株BP BD-12细胞生长有抑制作用;用40 h细胞菌龄添加OA条件下其转化产物为ω-1、ω-2和ω-3-羟基脂肪酸,其转化率和羟基脂肪酸得率最大值分别达到63%和12.3%;通过气质联用方法对产物组分分析,其ω-1-羟基脂肪酸占总羟基脂肪酸的70%,细胞培养过程中未有其它羟基脂肪酸检出。因此,菌株BP BD-12是一株较理想的ω-1-羟基脂肪酸工业化生产菌株。

The strain of Bacillus pumilus BD -12 has the ability to produce ω-1,ω-2 and ω-3 -hydroxy fatty acids （ω - HFAs） by bioconversion of fatty acid. At the condition of shake flask fermentation, the metabolic characters of Bacillus pumilus in oleic acid were studied using proteose as the main nitro source and glucose as the carbon source. The product of the bioconversion was measured by gas chromatography （GC） method. The following are the findings ： Glucose is a good carbon source for the cell growth and no HFAs accumulated. The cell growth of strain BD - 12 is inhibited by the substrate oleic acid. Using the 40 h age cultures, the maximum yield and ratio of ω- HFAs with total oleic acid addition reaches 63 and 12.3%, respectively, ω- 1 - HFA is the chief component among theo） - HFAs and reaches 70% of total ω - HFAs. No other ω- HFA is formed during the cell incubation phase. Therefore, Bacillus pumilus BD - 12 is an ideal strain for industrial production of ω-1 - HFA.