温、光、盐对硅藻STR01生长、总脂、脂肪酸的影响

为了优化新分离STR01的生态培养条件, 采用单因子试验和正交试验研究了不同温度、光照强度、盐度和温、光、盐三因素三水平对该藻的生长、总脂和脂肪酸组成影响。结果表明: 温、光、盐对STR01的生长、总脂和脂肪酸组成影响显著(P<0.05)。生长的适宜温度为15—35℃, 最适25—30℃(K值达0.679—0.682), 总脂含量积累的最适温度是25℃(总脂可达17.23%), 温度20℃时有利于该藻PUFA的积累, 可达34.23%。STR01生长的适宜光照强度为40—120 μmol/(m2·s), 最适光强为60 μmol/(m2·s), 光照强度40 μmol/(m2·s)有利于该藻的PUFA积累, 可达34.29%。STR01生长的适宜盐度为10—35, 最适盐度25, 盐度25时PUFA含量较高(43.42%)。正交试验结果表明温度对STR01的平均相对生长速率和总脂含量影响显著, 生长的最优组合: 温度30℃、光照强度60 μmol/(m2·s)、盐度25, 该组合下的生长速率达0.756; 总脂含量积累的最优组合: 温度30℃、光照强度60 μmol/(m2·s)、盐度20, 该组合下的总脂含量为20.00%。PUFA的最优组合: 温度25℃、光照强度60 μmol/(m2·s)、盐度20, 该组合下PUFA的含量为35.37%。综上所述: 该藻生长迅速, 总脂含量较高, PUFA丰富, 是一种可开发利用的耐高温浮游硅藻。

EFFECTS OF TEMPERATURE,LIGHT INTENSITY,SALINITY ON THE GROWTH RATE,TOTAL LIPID CONTENT AND FATTY ACID COMPOSITION OF STR01

To optimize the cultivation condition of microalgae, single-factor design and orthogonal experiments were performed to assess the growth rate, total lipid content and fatty acid composition of STR01 by temperature, light intensity and salinity. The results showed that all these ecological factors exerted significant effects on the growth, total lipid content and fatty acid composition of STR01 (P< 0.05) with the appropriate temperature for growth at 15—35℃, the optimum temperature at 25—30℃ (K-value 0.679—0.682) and the optimum temperature for total lipid content accumulation at 25℃ (17.23%). The highest PUFA content at 34.23% appeared at 20℃. The appropriate light intensity for growth was 40—120 μmol/(m2·s) and the optimum one was 60 μmol/(m2·s). The light intensity of 40 μmol/(m2·s) had the highest PUFA accumulation at 34.29%. The appropriate salinity for growth was 10—35 and the optimum salinity was 25. The orthogonal experiments showed that the optimum condition for growth was temperature 30℃, light intensity 60 μmol/(m2·s), and salinity 25, and that the optimum total lipid accumulation was temperature 30℃, light intensity 60 μmol/(m2·s) and salinity 20, and that the optimum PUFA content was temperature 25℃, light intensity 60 μmol/(m2·s), and salinity 20 at 37%. In conclusion, STR01 was promising prospect in future aquaculture with fast growth rate and high total lipid and PUFA contents.