Strategies for improved induction of lipid in Leptolyngbya sp. BTA 287 for biodiesel production.

• Identification of cyanobacterium. • Optimization of process parameter on yield of lipid and its composition. • Characteristics of microalgal lipid and biodiesel. In the present study, cyanobacterium BTA 287 was isolated from the north eastern region of India and identified as Leptolyngbya sp. using 16S rDNA technique. The cellular components of BTA 287 were composed of 7.4% of ash, 23.59% of carbohydrate, 42.15% of protein, 25.38% of lipid, and 1.5% of moisture. The 13.8% enhancement of lipid production was achieved during cultivation of BTA 287 in BG 11 medium supplemented with 25 mM of NaCl for 15 days at 28 °C under 6 k Lux with 14:10 day night ratio. The ratio of unsaturated and saturated fatty acid was estimated as 1.84. The saponification value, iodine value, cetane number, degree of unsaturation, long-chain saturation factor and cold filter plugging point of lipid extracted from BTA 287 were calculated as 212.52, 86.69, 52.48, 89.56 (wt%), 3.49 (wt%) and −5.51 °C respectively. This yield of biodiesel was found to be 82.54%. The density, kinematic viscosity, specific gravity, acid value, calorific value, flash point, pour point, water content, carbon residue and, copper strip corrosion of biodiesel were found to be 868 kg/m3, 4.95 mm2/s, 0.873, 0.38 mg KOH/g, 40.95 MJ/kg, 130 °C, −17 °C 0.025%, 0.86% and 1 respectively. The above fuel properties were general agreement with a globally accepted standard of biodiesel, indicating the suitability of this cyanobacterium BTA 287 as a promising feedstock for biodiesel. [ABSTRACT FROM AUTHOR]