布朗葡萄藻的培养基选择及其产物代谢规律

Medium selection of Botryococcus braunii and its metabolic mechanism

通过对布朗葡萄藻分别在Chu13、Chu13×2和BG-11培养基中培养结果的比较,发现在气升式光照生物反应器中Chu13培养基最有利于布朗葡萄藻的生长和烃的合成,培养15d后,其生物量和粗烃质量分数分别为1.82g/L和58.7%;棕榈酸、油酸和亚麻酸是布朗葡萄藻的主要脂肪酸组成,Chu13培养获得的藻体不饱和脂肪酸比例最高。Chu13培养基中布朗葡萄藻代谢规律的研究表明:粗烃含量随着生物量的增加而逐渐增大,15d后粗烃产量达到最大值1.07g/L,不同生长周期烃的组成保持一致,布朗葡萄藻的烃主要由C33H56和C34H58组成;在布朗葡萄藻生长周期中,不饱和脂肪酸的比例显著上升,培养15d达到64%以上。

Medium selection of Botryococcus braunii（B.braunii）was carried out in the air-lift photobioreactor.Three kinds of medium,including Chu13,Chu13×2 and BG-11,were compared for the culture of B.braunii.Chu13 was the best medium for the growth and hydrocarbon production of B.braunii,where the biomass of 1.82 g/L and the crude hydrocarbon content of 58.7% were achieved after 15 d cultivation.The main fatty acid composition of B.braunii included palm acid,oleic acid and linolenic acid.The unsaturated fatty acid proportion of microalgal biomass in Chu13 was higher than that in Chu13×2 and BG-11.The metabolic mechanism of B.braunii was also investigated in Chu13.In the culture process,crude hydrocarbon content increased with biomass and crude hydrocarbon production reached the maximum of 1.07 g/L after 15 d correspondingly.The hydrocarbon composition of B.braunii（Race B）kept consistent during the culture and it was consisted of two main hydrocarbons,C33H56 and C34H58.Results showed that the proportion of unsaturated lipid increased remarkably during the microalgal culture and it was more than 64% after 15 d.