中文摘要：

为了提高缺刻叶球藻的花生四烯酸（AA）产量,分别研究了不同光强、初始氮浓度及更换培养基的方式对缺刻叶球藻的生长和油脂、AA积累的影响。结果表明：同等光强下,高氮条件更有利于生物量的积累,但总脂含量和AA含量较低。在双侧高光的基础上更换培养基后,最高生物量增至7.36 g/L（高氮换高氮）,最高总脂含量和AA含量分别达到47.74%和6.18%（低氮换无氮）。对比发现,高氮换高氮最有利于缺刻叶球藻的生长,但AA产率相对低,仅为7.0 mg/（L·d）,而高氮换无氮、低氮换低氮、低氮换无氮3种更换方式均能提高AA产率,产率分别为14.0、15.3、17.0 mg/（L·d）。研究表明,缺刻叶球藻是生产AA的潜力藻株。

英文摘要：

In order to increase the yield of Lobosphaera incisa,the effects of light intensity,initial nitrogen concentration and medium replacement on the growth and accumulations of lipid and arachidonic acid were investigated.The results showed that under the same light intensity,L.incisa got higher biomass under the condition of high nitrogen concentration,while the contents of total lipid and arachidonic acid were lower.Replacing the medium under the bilateral high light condition,the highest biomass reached 7.36 g/L with the medium raplacement from high nitrogen concentration to high nitrogen concentration.In contrast,the highest contents of total lipid and arachidonic acid were 47.74% and 6.18% respectively which got through replacing the low nitrogen concentration medium with the nitrogen free medium.In conclusion,the cultivation partten of changing from high nitrogen concentration to high nitrogen concentration was the most benificial to the growth of L.incisa,but the productivity of arachidonic acid was only 7.0 mg/（L·d）.However,other cultivation parttens （replacing high nitrogen concentration with nitrogen free,replacing low nitrogen concentration with low nitrogen concentration,replacing low nitrogen concentration with nitrogen free） promoted the accumulation of arachidonic acid,and the productivities were 14.0,15.3,17.0 mg/（L·d）,respectivety.The research indicated that L.incisa was a potential strain for the production of arachidonic acid.