两步培养法提高栅藻的生物量及油脂含量

Improvement of biomass and oil content of Scenedesmus sp. by two-step cultivation

采用两步法培养栅藻，即在低光强一含氮条件下，培养栅藻至稳定期积累生物量，然后将栅藻转移至高光强-缺氮培养基中积累油脂。结果表明：在低光强-含氮培养基BG11（＋N）条件下，适宜栅藻生长的低光强为2000—2400lx，培养期为10d；转高光强-缺氮培养基BG11（-N）条件下培养，适宜栅藻积累油脂的高光强为6000—6500lx，培养期为6d。利用两步法培养栅藻，其生物量可达（0．957±0．126）g／L，油脂含量可达（23．35±0．2）％。两步法培养栅藻的生物量和油脂含量分别比常规单步法培养（10d）的提高了35．74％和近1倍。

Scenedesmus sp. was cultured to stationary phase under the conditions of low illumination intensity with nitrogen, and then cultured in medium with high illumination intensity and nitrogen deficiency to accumulate oil. The results showed that in nitrogenous BG11 medium with low illumination intensity, the optimal illumination intensity for the growth of Scenedesmus sp. was 2 000 - 2 400 lx, culturing for 10 d; in nitrogen deficiency BG11 medium with high illumination intensity, the suitable illumination intensity for oil accumulation of Scenedesmus sp. was 6 000 - 6 500 lx, culturing for 6 d. The biomass and oil content of Scenedesmus sp. cultured by two - step method were （0.957 ±0. 126） g/L and （23.35 ±0.2） % respectively, increasing by 35.74% and 100% than that cultured by common one -step method.