Eva Mathias Sosovele and Hosea K.M.M and Baraka S
Department of Molecular Biology and Biotechnology, University of Dar es Salaam, P.O. Box 35179, Dar es Salaam, Tanzania
The present study aimed at screening for cytotoxicity and antioxidant properties of extract from Streptomyces sp. isolated from Dar es Salaam mangrove sediments. The Streptomyces sp. (isolated in a previous study), was cultivated in broth and the non-polar fractions of its extracellular metabolites were harvested via ethyl acetate (liquid-liquid) extraction. The obtained extract was first screened for cytotoxicity activity using brine shrimp lethality bioassay. The extract was found to possess cytotoxicity activity with the LC50 value of 236.86µg/ml. Antioxidancy was assessed on the basis of scavenging ability of the stable 1, 1 Diphenyl-2-picry Hydrazyl (DPPH). Results of the screening for antioxidant activity showed that, the crude extract of Streptomyces sp had Antioxidancy scavenging ability which ranged between 94.31% - 95.69% at the concentration ranging from 4200 µg/ml to 14000µg/ml. These findings proved that the strain had potent antioxidant activity as the Ascorbic Acid which is the known antioxidant. These results give facts that, the marine Streptomyces sp. could be a promising source of drugs and have enormous prospective in the pharmaceutical meadows.
Keywords: Mangrove, sediments, Streptomyces sp, Antioxidant activity.