Enhanced intracellular lipid in Nannochloropsis sp via random mutagenesis and flow cytometric cell sorting

Nannochloropsis sp., a promising marine microalga for biodiesel feedstock production, was treated with the mutagen ethyl methanesulfonate (EMS) to induce random mutagenesis which was then followed by flow cytometric cell sorting to isolate mutants with an enhanced intracellular lipid content. Treatment resulted in up to a four-fold increase in total fatty acid content in the mutant strain, a 30% increase in palmitoleic acid (16:1) and a 45% decrease of eicosapentaenoic acid (20:5n3) relative to that of the wild-type (WT). The mutant produced fatty acid more prolifically than the WT during both exponential and stationary phases of growth. This study highlights the ability to enhance intracellular lipid accumulation in microalgae using random mutagenesis in conjunction with flow cytometric cell sorting. (C) 2012 Elsevier B.V. All rights reserved.