胭脂虫繁养条件对胭脂红酸含量的影响

对不同气候类型、繁养方式繁养的胭脂虫的胭脂红酸（CA）含量进行测定，结果表明：不同气候类型的胭脂红酸质量分数为14．56％-26．29％，平均为19．78％；春虫、夏虫和秋虫的胭脂红酸质量分数分别为19．79％、21．03％和18．51％。同一气候类型、自然条件下的胭脂红酸含量为17．71％～19．79％，平均18．77％；遮阴棚中的为20．84％-23．96％，平均22．06％；塑料大棚中的为18．74％～26．29％，平均22．24％；胭脂红酸平均含量（B试验点）分别为春虫23．35％，夏虫20．45％，秋虫19．27％。收虫季节、试验点的胭脂红酸含量无显著性差异，繁养方式和胭脂虫级别的胭脂红酸含量呈极显著性差异。依此提出在南亚热带气候区应以塑料大棚和遮阴棚繁养胭脂虫，而中亚热带和北亚热带气候区以塑料大棚繁养为宜。

Effects of Culture Conditions on Growth and Docosahexaenoic Acid Production from Schizochytrium limacinum

The effects of temperature, initial pH, salinity of culture medium, and carbon and nitrogen sources on growth and doco- sahexaenoic acid (C22 : 6 n-3, DHA) production from Schizochytrium limacinum OUC88 were investigated in the present study. The results revealed that the optimal temperature, initial pH and salinity level of the medium for DHA production were 23℃, 7.0 and 18, respectively. Glucose was proved the best carbon source for the growth and DHA production from S. limacinum. Among the nitrogen sources tested, soybean cake hydrolysate, a cheap by-product, was found to be effective for the accumulation of DHA in S. lima- cinum cells. In addition, increasing the concentration of carbon sources in the medium caused a significant increase in cell biomass; however, accumulation of DHA in cells was mainly stimulated by the ratio of C/N in the medium. Under the optimal culture condi- tions, the maximum DHA yield achieved in flasks was 4.08 g L-1 after 5 d of cultivation.