Madhavarani Alwarsamy and Ramanibai Ravichandran
The antibacterial activity of acetone and methanol extracts of marine red alga Kappaphycus alvarezii (red algae) collected from Mandapam Coast (Gulf of Mannar) was screened invitro for their antibacterial activity against four human bacterial pathogens Viz.; Bacillus subtilis, Staphylococcus aureus, Proteus mirabilis and Vibrio cholerae using well diffusion method. In this study it was suggested that the methanol and acetone extracts were the best medium for the extraction of the effective antibacterial material from the red alga Kappaphycus alvarezii. It was observed that the methanolic extract recorded maximum activity against Staphylococcus aureus and Proteus mirabilis, whereas the acetone extract exhibited antibacterial effect against Bacillus subtilis and Staphylococcus aureus. The maximum inhibition zone (11mm) was noted in the methanolic extract of Kappaphycus alvarezii against Proteus mirabilis.