一株葡萄藻的分离、鉴定及产烃性能评价

ISOLATION, IDENTIFICATION AND EVALUATION OF HYDROCARBON PRODUCING PERFORMANCE OF ONE BOTRYOCOCCUS STRAIN

研究从我国海南博鳌海边的淡水池塘水样分离获得一株绿藻ENN41。显微形态观察表明,ENN41的形态特征属于葡萄藻。进一步克隆ENN41的核糖体小亚基18S r RNA片段,利用分子生物学软件进行比对分析,结果表明ENN41的18S r RNA基因序列与布朗葡萄藻(Botryococcus braunii)同源性最高,说明ENN41为一株布朗葡萄藻(B.braunii)。ENN41在柱式反应器中培养16d,单位体积产率为0.483 g/(L·d),粗烃占干重的含量为56.6%;主要脂肪酸为油酸(C18:1)、十八碳四烯酸(C18:4)和棕榈酸(C16:0),三者之和占总脂肪酸的72.6%;利用尼罗红染色,清晰可见大量的油脂分布在细胞内和胞外基质中。ENN41在板式反应器中培养16d,单位体积产率为0.234 g/(L·d),粗烃占干重的含量为20.0%。上述研究表明,ENN41是具有较高的生长速度和粗烃积累能力的布朗葡萄藻(B.braunii)藻株,具有产业化应用潜力。

ENN41 is a freshwater strain isolated from Bo＇Ao coast of Hainan Province. Microscopic observation showed that ENN41 has the unique morphological character of genus Botryococcus. The 18S rRNA gene of ENN41 was cloned for further species confirmation at molecular level. The homologous analysis showed that the 18S rDNA gene of ENN41 was highly homologous to the species of Botryococcus braunii in GenBank. ENN41 achieved a biomass productivity of 0.483 g/（L·d） and crude hydrocarbon content of 56.6% for 16 days culture in column reactor. The main fatty acids were oleic acid （C18：1）, octadecatetraenoic acid （C18：4） and palmitic aid （C16：0）, accounting for 72.6% of the total fatty acid. Large amount of lipid stained with Nile red in the extracellular matrix. ENN41 reached a high productivity after 16 days culture in plate bioreactor[0.234 g/（L·d）] with 20% crude hydrocarbon. All the results showed that ENN41 is a natural Botryococcus braunii strain with high productivity of biomass and lipids and high potential for industrial application.