中文摘要：

【目的】以标志链带藻（Desmodesmus insignis）为实验材料,研究不同氮源及其浓度对该藻生长、总脂和淀粉（碳水化合物）含量的影响,为该藻在生物能源方面的应用提供一定的理论依据。【方法】以硝酸钠、碳酸氢铵或尿素为氮源,5个氮浓度（3、6、9、12和18 mmol/L）的BG-11培养基培养标志链带藻,采用干重法测定生物质浓度、重量法测定总脂、苯酚-硫酸法测定、总碳水化合物和淀粉的含量。【结果】标志链带藻在3种氮源下均能很好的生长。最高油脂含量出现在3 mmol/L硝酸钠实验组,达到32.61%（d.w）。当18 mmol/L碳酸氢铵作为氮源时,总碳水化合物与淀粉的含量以及产率都达到最高,分别为56.54%（d.w）和55.33%（d.w）、0.24和0.23 g/（L·d）。以尿素为氮源时,其生物质浓度和各组分含量与其它氮源实验组差别不大,均有利于该藻的生长及各生化组分含量的积累。【结论】以该藻种生产生物能源的成本等综合考虑,以18 mmol/L碳酸氢铵和尿素为氮源培养标志链带藻最优。

英文摘要：

[Objective] In order to improve biofuel production by Desmodesmus insignis,we studied the effect of different nitrogen sources and concentrations on the growth,total lipids,carbohydrate and starch accumulation of Desmodesmus insignis.[Methods] D.insignis was cultivated in basic general-11 medium containing 5 different initial nitrogen concentrations（3,6,9,12 and 18 mmol/L） supplied in the form of sodium nitrate,ammonium bicarbonate and urea.Biomass was determined by dry weight,total lipids by gravimeter,and carbohydrates and starch by phenolsulfuric acid method.[Results] NaNO_3,NH_4HCO_3 and CO（NH_2）_2 were all suitable for the growth of D.Insignis.When 3 mmol/L NaNO_3 was used,the peak lipid content reached to 32.61%（d.w）.The maximum content and productivity of carbohydrate and starch were 56.54%（d.w）,55.33%（d.w） and 0.24 g/（L·d）,0.23 g/（L·d） respectively,when 18 mmol/L NH_4HCO_3 was used.Urea could also obtain relative high content of biomass,total lipids,carbohydrates and starch.[Conclusion] Integrating these results with production costs,we could suggest ammonium bicarbonate and urea as nitrogen source at the concentration of 18 mmol/L.