Abstract
•Lipid content was studied in two Phormidium and two Oscillatoria species.•Abiotic factors viz. PAR, temperature, pH on biomass, lipid content was evaluated.•2000 lx, 37–40 °C and pH are optimal factor higher lipid content in all strains.•Oscillatoria sp. FW01 is promising over other strains with rich lipid, fatty acids.
Considering the glitches in making commercially realistic fuel, this research article has demonstrated the lipid accumulation in four fast growing, filamentous cyanobacterial strains. On day 26, the lipid content estimated was 6.7, 8.2, 10.2, and 9.4% from Phormidium sp. FW01, Phormidium sp. FW02, Oscillatoria sp. FW01, and Oscillatoria sp. FW02, respectively. Of the photosynthetically active radiation (PAR) tested, 2000 lx was found to higher biomass and lipid at about 1.83 g/L and 12.5%, respectively for Oscillatoria sp. FW01. Of <5 °C, 15 °C, 25 °C, 37–40 °C tested, 11.2% lipid was extracted from Oscillatoria sp. FW01 grown at 37–40 °C and pH did not make any changes in biomass and lipid content. The optimized abiotic conditions showed higher polar lipids about 75% in all the tested cyanobacteria and further, Oscillatoria sp. FW01 yielded 57% fatty acid methyl ester, which contains desirable fatty acids C 16:0, C 16:1, C18:1, C18:3 for high quality biodiesel.