除草剂San9785在高EPA后棘藻品系筛选中的应用

Selection of high EPA content strains of Ellipsoidion sp. by using Herbicide San9785

后棘藻(Ellipsoidion sp.)是一种高脂海洋微藻,采用微生物筛选平板的方法,利用多不饱和脂肪酸EPA合成的阻断剂——除草剂San9785对紫外线诱变的后棘藻细胞进行了高EPA个体的筛选,气相分析结果显示,在检测的8株筛选品系中,5株EPA含量高于出发藻种,平均提高了121.6％,另3株EPA含量低于出发藻种,平均降低的量为12.6％,EPA含量最高的品系达到总脂肪酸的26.22％,比出发藻种提高了212％.提示除草剂San9785可以作为一种高效筛选压力,选育多不饱和脂肪酸含量丰富的微藻品系。

In order to get high EPA content strains from microalgae Ellipsoidion sp., the algae were treated by herbicide San9785 which was reported as one of the most effective inhibitors of EPA synthesis, especially in the pathway from C18: 2ω - 6 to C18: 3ω - 3. Alga cells were spread on the selective plates which contained San9785 at the concentration of 0.1 mmol/dm3, after radiated by U. V. light, plates were cultured under optimal conditions. One month later, a few microalgal colonies appeared and were transferred into liquid medium individually. Fourteen strains were selected. The growth rate, total lipids content and fatty acids were compared among these strains vs. the initial strain. Results show that EPA content of the selected strains increased as well as the ratio of ω - 3 to ω -6 polyunsaturated fatty acids. The highest EPA content in strain E- 14 is 26.2% in total fatty acids, 212% higher than that of the initial strain, suggesting that herbicide San 9785 is an efficitive and practical chemical compound in selection of high EPA content in microalgae Ellipsoidion sp.