SCREENING OF POTENTIAL MICROALGAE SPECIES FROM DIFFERENT NATURAL ENVIRONMENT FOR BIODIESEL PRODUCTION

Microalgal samples were collected from different regions of India. The samples thus obtained were serially diluted, colonies were further purified and identified as Desmodesmus abundans, Scendesmus pectinatus, Tetranephris brasiliensis, Desmodesmus armatus, Scendesmus costato-granulatus, Neocystis brevis, Chlorella sorokiniana, Scendesmus acutus, Pseudomuriella species and Chlorella minutissima by 18s rRNA sequencing. The effect of growth conditions was studied under different media such as Bold Basal Media (BBM), Blue Green 11 media (BG11) and Tris-Acetate Phosphate media (TAP). The highest growth rate was occurred in Desmodesmus abundans on 19th day in TAP media whereas the lowest growth rate was occurred in Tetranephris brasiliensis in BBM media. Under similar environmental conditions average specific wet and dry biomass were found maximum in Chlorella minutissima, Desmodesmus abundans and Scendesmus costatogranulatus in TAP media when compared to BBM and BG11. The highest amount of lipid was obtained in Desmodesmus armatus (43.7%) grown in TAP media. Nile red staining and thin layer chromatography confirms the accumulation of total lipids. The reaction condition with that of n -hexane to methanol ratio 1:2, solvent dosage 5.0 ml, reaction temperature 90°C, reaction time 2.0 h and catalyst volume 0.5 ml of the direct transesterification can reach the conversion yield of 90.23%, 89.25% and 86.65% found in Desmodesmus abundans, Desmodesmus armatus and Scendesmus costato-granulatus respectively. There is a prospective in algal biotechnology by exploitation of different media composition for the growth formulation in microalgae species which is inexpensive for biomass cultivation in large scale production of lipids that can be harnessed for biodiesel production. KeywordsMicroalgae, Biomass, Lipids, Transesterification and Biodiesel