Ecology, Environment and Conservation Paper

ISOLATION, IDENTIFICATION AND OIL QUALITY OF DIFFERENT ALGAL STRAINS

Jyoti Rai, S.K. Gosal, Sucheta Sharma and S.K. Thind

Abstract

A total of 20 different algal isolates were isolated from stagnant water samples collected from different districts of Punjab, Rajasthan and Himachal Pradesh. On the basis of morphological characterization, these algal isolates were tentatively identified as Chlorella, Oedogonium, Aphanocapsa, Phormidium, Spirogyra, Anabeana, Scenedesmus, Tolypothrix, Anacystis, Microcystis, Volvox and Spirulina. Data analysis revealed that the isolate JA8 had highest growth rate after 15 days of incubation. Increase in pH of the medium was recorded with the growth of algal isolates after 15 days of incubation and the highest increase in pH was recorded in JA18 (10.6). Supplementation of urea to the growth medium resulted in less fluctuation of pH of the medium. The isolate JA11 showed highest dry biomass weight(7.211 g/l) after one month of incubation. All the 20 isolates,were screened for their lipid content and the highest lipid content was recorded in the isolate JA8 (5.60 %). An increase in lipid content in the isolate JA8 (5.60 % to 7.52 %) and JA9 (5.25% to 7.11) was observed with the addition of glucose (10 g/l) to the growth medium. The highest saponification (169.69 mg/g of oil) and acid value (4.75 mg/g of oil) was shown by the isolate JA8. The fatty acid composition of three algal isolates JA8, JA9 and JA15 was determined with Gas liquid Chromatography analysis which indicated that the lipid fraction mainly comprises ofstearic acid, pentadecanoic acid, oleic acid and saturated fatty acids. Hence, the results revealed that the isolate JA8 may be considered best among the isolates.However, this lipid content is very low to use this isolate for biofuel production. So, there is need to explore the possibility of isolating another algae with high lipid content.