氮源种类及浓度对眼点拟微绿球藻生长密度、油脂产率和二十碳五烯酸含量的影响

Effects of nitrogen sources on growth density, lipid yield and eicosapentaenoic acid of Nannochloropsis oculata

氮源是影响微藻生长和油脂积累的重要因素,文中通过单因素试验比较了NaNO3、CO(NH2)2、NH4Cl、CH3COONH4及其浓度对眼点拟微绿球藻生长密度、油脂产率、二十碳五烯酸(EPA)含量的影响。结果表明:NH4+更易被眼点拟微绿球藻利用,能更好地促进微藻生长和油脂积累;氮浓度的增加有利于微藻的生长和藻油脂肪酸的去饱和,但不利于微藻油脂的积累。在实验考察的氮源种类和浓度范围内,CH3COONH4是促进眼点拟微绿球藻生长和油脂积累、EPA生成的适宜氮源,其适宜的浓度为5.29 mmol/L。

Nitrogen source is one of the important factors that affect the microalgae growth and lipid accumulation. We studied the effects of various nitrogen sources （i.e. NaNO3, CO（NH2）2, NH4Cl and CH3COONH4） and amount on the growth density, lipid yield, and eicosapentaenoic acid （EPA） content of Nannochloropsis oculata by single factor experimental method. The results show that N. oculata preferred NH4＋ as nitrogen source rather than NO3 and CO（NH2）2. NH4＋ could promote the growth and lipid accumulation of N. oculata. With the increase of nitrogen concentration, the biomass and the content of polyunsaturated fatty acid （PUFA） increased, but the content of lipid decreased. CH3COONH4 was the most suitable for growth, accumulation of lipid and EPA of N. oculata among the four investigated nitrogen sources. The optimal concentration was 5.29 mmol/L.