Danielli M.M. Dantas, Romero M.P.B. Costa, Maria G. Carneiro-da-Cunha, A. O. Galvez, A. R. Drummond, and Ranilson S. Bezerra
Various crude extract preparations (ethanol, methanol, buthanol, acetone, DMSO and water) from the green alga Chlorella vulgaris were examined for Antioxidant activity, Phytochemical screening and Antimicrobial properties. In vitro free radical quenching and total antioxidant activity of extracts were investigated with 1, 1-diphenyl-2- picryl hydrazyl (DPPH), and compared with cathequin and Gallic acid as positive controls. In most cases, results showed a significant association between the antioxidant potency and the total phenolics content. The aqueous extract showed both the highest antioxidant activity for inhibition scavenging (68.5%) and highest phenolic content (3.45 mg/ mL). Antimicrobial activities were carried out using disc diffusion assays and the broth dilution method against Gram-positive and Gram-negative bacteria. Results demonstrated activity between the aqueous extract and most specimens (Proteus mirabilis, Klebsiella pneumoniae, Salmonella enteretidis, Bacillus subtilis and Escherichia coli). These results suggest that the aqueous crude extract of C. vulgaris could be considered as a biological antioxidant and antimicrobial agent, and a valuable tool for the biotechnology field.