光强与氮源对绿球藻GN38生长和油脂积累的影响

Effect of light intensity and nitrogen source on the growth and lipid Chlorococcum sp.GN38

光强与氮源是影响微藻生长与物质积累的重要因子,文章研究了光强、氮源、氮源浓度对一株自然条件下分离的绿球藻GN38的生长和油脂积累的影响。实验通过在不同光照强度(179μmol/m2·s-1和84μmol/m2·s-1)条件下,分别以具浓度梯度(1N,1/3N,1/5N)的NaNO3和CO(NH2)2为氮源培养绿球藻,获得了GN38生长与产油的较佳条件。结果表明,较高光强能促进GN38生长和总脂积累;CO(NH2)2有利于GN38积累油脂;不同氮源均表现出氮源浓度与生物量成正比,无氮组除外;179μmol/m2·s-1光强、1/5N时GN38的总脂含量最高。综合考虑,产油微藻GN38的最佳培养条件为179μmol/m2·s-1光强和0.528 g/L CO(NH2)2,在此条件下干重达到6.7g/L,总脂含量为38%,总脂产量为2.54 g/L,脂肪酸成分中C16和C18含量高达95.15%。实验为该藻的后续深入研究及产业化培养奠定了基础。

Light intensity and nitrogen source is the important factor of microalgae growth and mate- rial accumulation. This paper studied the effect of light intensity, nitrogen source and nitrogen con- centration on growth and lipid accumulation of GN38 isolated from natural environment. Under differ- ent light intensity （179 μmol/m^-2·s^-1 and 84 μmol/m^-2·s^-1） and different concentration of sodium nitrate and urea （1N, 1/3N and 1/5N） this paper obtained the optimum conditions of growth and oil accumula- tion of GN38. Results are shown below. Higher light intensity could accelerate the growth and lipid accumulation of GN38, urea is conducive to lipid accumulation, concentration of nitrogen source was proportional to the biomass using sodium nitrate and urea, lipid content of GN38 was highest under 179 μmol/m^-2·s^-1 light intensity and 1/5 N nitrogen concentration except the conditions of no nitrogen. On the whole, the best culture conditions of oil-producing microalgae GN38 was 179 μmol/m^-2·s^-1 light intensity and 0.528 g/L urea. The cell dry weight was 6.7 g/L, the lipid content was 38%, the lipid yield was 2.54 g/L, the content of C16 and C18 was 95.19% in fatty acid composition. This experiment laid a foundation for subsequent research and industrialization cultivation of this microalga.