元素缺乏和外加碳源对小球藻（Chlorella sp KMMCC FC-21）生长和油脂积累的影响

从海南本地水域分离得到一株高含油藻,通过18S rDNA鉴定其为Chlorella sp KMMCC FC-21。将其培养在高碳培养基HSM和低碳培养基BG11和SE以及它们相应氮元素、硫元素和磷元素缺乏的培养基中,研究上述三种元素缺乏对其生物量和油脂积累的影响。结果表明:氮元素和硫元素缺乏使其生物量大幅减少,但却能促进其油脂的积累,在高碳情况下其促进作用更加明显,而磷元素的缺乏只能小幅增加其含油量。在低碳硫元素缺乏的SE培养基中分别添加30 mmol/L乙酸钠和25 mmol/L葡萄糖时,其生物量分别提高了200%和160%,其油脂含量分别提高了120%和72.7%。在HSM、HSM-N、HSM-P和HSM-S培养基中细胞组分分析表明:氮元素、硫元素和磷元素缺乏促进其细胞内油脂积累的同时却使总糖和总蛋白的含量减少,此外也使叶绿素含量和光合效率降低。

Nutrien Elements Deficiency and Carbon Source Addition Affect on the Growth and Lipid Accumulation in Chlorella sp KMMCC FC-21

A high oil microalgae strain collected from Hainan was defined as Chlorella sp KMMCC FC-21 through 18S rDNA identification in the research. This strain was grown in the high carbon medium HSM, low carbon medium BG11 and SE, and their nitrogen(N), sulfur (S)and phosphorus (P) free medium respectively to study the effects of these three elements deficiency on the biomass and oil accumulation. Results showed that N and S starvation led to dramatically increase in cellular lipid content, especially in high carbon medium, which was accompanied by remarkable decrease of biomass. However, the starvation of P could only give rise to slight increase of lipid content. When cultured in SE-S with 30 mmol/L sodium acetate and 25 mmol/L glucose respectively, the corresponding biomass of Chlorella sp KMMCC FC-21 was increased by 200% and 160% compared to those in SE-S, and the corresponding lipid content was increased by 120% and 72.7%. Moreover, the component of cells was also detected. The results indicated that cells grown in HSM-N, HSM-S and HSM-P contained higher lipid content but lower total protein, total carbohydrate content, chlorophyll content and photosynthesis efficiency comparing to the control.