Vol. 2, Issue 9, Part J (2016)

Abstract
Seaweeds offer a rich source of bioactive molecules; the present study was carried out to the antimicrobial activity of Methanol extract of three species of marine macroalgae were screened for their antimicrobial potency against seven pathogenic bacterial strains. Three seaweeds Ulva lactuca, Sargassum wightii and Gracilaria edulis were collected from four different stations (Station 1 (Chinnamuttom), Station 2 (Mandapam), Station 3 (Rameshwaram) and Station 4 (Thondi) of South East coast of India. Their antibacterial activity was evaluated. The methanolic extracts of U. lactuca showed high activity against Salmonella typhii (10±1.4) in station I. S. wightii inhibited Streptococcus faecalis ( 6.5± 0.7) the most in station III and G. edulis showed a maximum zone of inhibition against Streptococcus faecalis (8± 0.6) in station III. Among these three species U. lactuca significantly showed maximum antimicrobial activity than the other species (P<0.05). Results of the present study confirmed the potential use of seaweed extracts as a source of antibacterial compounds.