The potential of marine ascidians as sources of natural antioxidant and antibacterial agents from Manado, North Sulawesi

The ascidians are an excellent source of bioactive compounds as natural antioxidants, and they have particular interest due to their beneficial effects on health. Sample preparations for antioxidant and antibacterial activity evaluation of the ascidians Lissoclinum patella, Didemnum molle and Herdmania momus used methanol as extraction media. In the present study, the antioxidant activity was determined through superoxide dismutase (SOD) assay and the antibacterial activity was tested against pathogenic bacteria Enterococcus faecalis. Results showed that methanol extracts of L. patella, D. molle and H. momus had an antioxidant activity against SOD with IC50 of 300, 82 and 52 ppm, respectively. On the other hand for antibacterial activity, two ascidian extracts (D. molle and H. momus) showed inhibition zones values of 9.2 and 6.9 mm at 10% together with chlorhexidine as positive control, while the ascidian L. patella was inactive. These data indicated that ascidians had potential bioactive compounds as source of natural antioxidants.