产DHA菌株的诱变育种

以海水中分离得到产DHA的酒香酵母(编号为7-3)作为出发菌株,对其进行单一及复合诱变处理,初筛采用分光光度法确定菌体中油脂的相对含量,选择吸光度相对较高的菌株进行复筛,复筛采用有机溶剂萃取法测定油脂含量、气相色谱法测定DHA含量。单一诱变的菌株H-1的脂肪含量达到43.8%,为对照的4倍,经复合诱变后得到1株编号为H-Z-6-3的菌株其油脂含量达50.4%,诱变后油脂中DHA的含量提高较少。

Mutation Breeding of DHA-Producing Strain

DHA-producing Brettanomyces strain 7-3 screened from seawater was treated as starting strain with single or multiple mutageneses.And during the initial screening the content of fat in the cells was determined with spectrophotometry,strains with higher absorbance were selected and screened repeatedly.And extraction with organic solvent and gas chromatography were adopted to determine the fat content and DHA content respectively during the re-screening.The fat content of strain H-1 with single mutagenesis was as much as 43.8% 4 times of the control,and the fat content of strain H-Z-6-3 with multiple mutageneses was as much as 50.4%,however,the DHA content in the fat increased less after the mutagenesis.