TAPPING THE ANTIOXIDANT POTENTIAL OF A NOVEL ISOLATE - CHLORELLA EMERSONII

摘要: There is a quest for alternative and economical antioxidants, to be substituted for the chemical ones used in personal and health care sectors. These alternative sources are usually of plant or algal origin. With a known potential antioxidant activity of freshwater microalga, and the obvious advantage of scaling up in comparison to seaweeds/macroalgae, this study isolates and evaluates the antioxidant principles from a so far an unexplored species of Chlorella. Materials and Methods Chlorella was enriched from a fresh water pond in Chu‟ s medium No. 10 at 28±30 C and was identified as Chlorella emersonii morphologically as well as by 18s rDNA sequencing (NCBI accession number-KJ725233). C. emersonii was cultivated in BG-11 medium at different temperatures, so as to optimize its temperature for biomass production. The mass obtained was then dried and three different solvents: water, methanol and hexane were used to extract the antioxidants. The antioxidant activity and the total phenolic content were quantified by FRAP and Folin-Ciocalteau methods respectively. Results Highest activity of 15.348±0.0908 and 17.975±0.436 mg ascorbic acid g-1; 9.963±0.3667 and 18.23±0.525 mg ascorbic acid g-1 for aqueous and methanolic extract respectively. The antioxidant potential of the hexane fraction was found to be the lowest 0.257±0.024 and 0.380±0.10 mg ascorbic acid g-1. Conclusion The correlation coefficients for antioxidant potential and phenolic content of aqueous fractions was found to be R 2= 0.9999 indicating significant contribution of the phenolic compounds to the antioxidant activity for Chlorella emersonii KJ725233.