一株产油微藻的分子生物学鉴定及其油脂含量测定和成分分析

Molecular identification, oil content determination and composition analysis of an oil-microalgae

从内蒙古乌梁素海淡水水体分离得到一株产油微藻DZ306,通过形态观察可知其为Nitzschia.sp.。建立了尼罗红染色快速检测油脂含量的方法,并对该菌株的油脂成分进行分析,发现其富含多不饱和脂肪酸二十碳四烯酸(AA)和二十碳五烯酸(EPA)。PCR扩增该菌株18S rDNA序列,测序获得长度为1 562 bp的片段,用BLAST软件对基因序列的同源性进行分析,其与N.palea的相似度为99%;用ClustalX软件进行多序列对齐排列,用MEGA4.0软件采用Neighbor-Joining算法构建进化树,证明所分离得到的微藻DZ306为Nitzschia palea。

A strain of oil-producing microalgae DZ306 was separated from Inner Mongolia Wuliangsuhai freshwater water, identified as Nitzschia sp. by morphological properties. Nile Red staining as a rapid method was established for lipid determination from DZ306. Analysis of the fatty acid compouds of the strain indicated that fatty acids of Arachidonic Acid （AA） and Eicosapentaenoic Acid （EPA） were rich in 18S ribosomal DNA sequences of DZ306 DZ306. Were augmented and analyzed, and the results of amplification indicated that the length of PCR productions was 1 562 bp. Then, homology analysis was performed using BLAST in NCBI, and the results showed that the fragment of 18S rDNA of DZ306 had a high homology （99%）with that of Nitzschia palea. The phylogenetic trees （Neighbor- Joining） based on the sequences revealed that this species clustered with N. palea. So DZ306 was identified as Nitzschiapalea.