氮含量对等鞭金藻生长及生化组分的影响

目的]为了确定利于等鞭金藻生长及不同生化组分积累的优化氮含量.方法]采用流加培养方式和单因素考察,研究5种硝酸钠浓度时等鞭金藻生物量及细胞内生化组分含量随培养时间的变化趋势.结果]在在流加培养方式下,适合等鞭金藻生长和细胞内蛋白质积累的硝酸钠含量为150 mg/L培养液；在含37.5 mg/L硝酸钠的培养液中,等鞭金藻细胞内的总脂含量在培养中期达到最高值；而在含75 mg/L硝酸钠的培养液中可溶性总糖和淀粉含量分别在培养的中后期和后期达到最大值.结论]培养液中的氮含量对等鞭金藻细胞生长及细胞内生化组分的含量有重要影响.这可能由不同氮浓度下等鞭金藻的代谢途径发生变化所致.从等鞭金藻作为生物能源资源的角度考虑并兼顾生物量,应选择含75 mg/L硝酸钠的培养液培养等鞭金藻.

Effect of Nitrogen Content on Growth and Biochemical Composition of Isochrysis galbana

Objective ] The optimal contents of nitrogen were investigated for increasing the biomass and the contents of biochemical composi- tion in Isochrysis galbana. Method] The change trends with different concentrations of sodium nitrate were studied by means of fed-batch cul- ture and single factor analysis in the whole eulture period. Result] Under the condition of fed-batch culture, 150 mg/L sodium nitrate was suitable for the growth of L galbana and synthesizing protein in it, total fats reaehed the maxmium at middle period in 37.5 mg/L sodium ni- trate of medium, while total soluble sugars and starch were up to their greatest amount at the mid-later and later period in 75 mg/L sodium ni- trate of medium, respectively. Conclusion] Nitrogen is one of necessary elements for growing of microalgae, it might be associated with the shift of metabolism path under different contents of nitrogen. From the points of bioehergy resource and biomass supply, 75 mg,/L sodium ni- trate was chosen to culture L galbana.