Optimisation of the critical medium components for better growth of Picochlorum sp. and the role of stressful environments for higher lipid production

showed that the main fatty acids were palmitic acid (29%), linolenic acid (26.5%), linoleic acid (23.5%), hexadecatrienoic acid (11%) and hexadecadienoic acid (8.5%). As it is known that culture conditions greatly influence the composition of microalgae, the experiments were designed to optimise the composition of the medium in order to increase Picochlorum sp. growth from OD680nm = 0.53 to OD680nm = 2.2 and lipid accumulation from 163gkg −1 to 190gkg −1 . The highest lipid contents of 570 and 585gkg −1 were achieved under phosphate starvation and sodium carbonate supplementation, respectively. Under these conditions, the fatty acid profile is dominated by mono-unsaturated and polyunsaturated acids, and is therefore suitable for aqua-culture feeding. However, under high salinity, growth and lipid synthesis are inhibited, and the fatty acids are saturate, and the product is therefore suitable for biodiesel. CONCLUSION:Thishighlipidcontentrichinessentialfattyacids,omega-6andomega-3,endorsesthiswildstrainofPicochlorum sp. as a promising feedstock for aqua-culture and human nutrition or for the production of biodiesel. c � 2013 Society of Chemical Industry