Molecular Identification of a Species in Genus Nannochloropsis

摘要

Nannochloropsis is a genus of marine eukaryotic unicellular algae,which belongs to class Eustigmatophyceae.The spe-cies of Nannochloropsis which are fine rotifer feed and rich in eicosapentaenoic acid(EPA)are economically important.Species in this genus are usually 2-5μm in size and are morphologically similar,which makes their identification difficult.We obtained a monoclone of Nannochloropsis with plating method in this study.DNA was extracted and the quality was determined by restriction enzyme digestion and spectrophotometer analysis.The DNA extracted was used to amplify the sequences of 18S ribosomal RNA gene,ITS region of ribosomal RNA transcription unit and rbcL gene.The phylogenetic analysis was carried out by constructing the neighbor-joining trees with Tamura-Nei distances.The phylogenetic analysis showed that the monoclone is N.oceanica.