Aqueous extract of seven species of marine macroalgae were screened for their antimicrobial
potency against ten pathogenic bacterial strains. Ulva fasciata, Gracilaria corticata, Sargassum
wightii and Padina tetrastromatica showed significantly higher activity against 70% of the
tested bacterial isolates. The maximum zone of inhibition was noted for the red alga G.corticata
against Proteus mirabilis (17mm) and brown alga P. tetrastromatica against the pathogens
Staphylococcus aureus and Vibrio harveyi (15mm). The general trend of inhibitory activity
was higher towards Gram negative bacteria
