产烃葡萄藻在气升式光生物反应器中的分批补料培养

在3 L气升式光生物反应器中进行了产烃葡萄藻的培养. 批式培养时，葡萄藻消耗氮、磷的速度较快，培养液中氮、磷营养盐的缺乏限制了藻细胞进一步生长和增殖. 采取分批补料方式，使培养液中KNO3和K2HPO4浓度分别维持在100和30 mg/L，可克服氮、磷限制问题. 与批式培养相比，生物量从1.3 g/L增加到1.9 g/L，烃含量从占细胞干重的22%提高到29%，从而使烃产量从0.286 g/L增加到0.551 g/L，提高了92.6%.

Fed-batch Cultivation of Botryococcus braunii in an Air-lift Photobioreactor

The culture of Botryococcus braunii was carried out in a 3 L air-lift photobioreactor. The batch cultivation results showed that the concentration of nitrate and phosphate ions decreased quickly by algal consumption, which limited the growth of Botryococcus braunii. Therefore, the fed-batch cultivation mode in which nitrate and phosphate were maintained in a certain range of concentration by multiple feeding in the late stage of fermentation was tested. Compared with batch cultivation, the cell concentration increased from 1.3 g/L to 1.9 g/L , hydrocarbon content increased from 22% to 29% on dry weight basis and the yield of hydrocarbon was greatly improved from 0.286 g/L to 0.551 g/L.