The production of antibacterial compounds from the marine algae is considered to be an indicator of the capacity of the seaweeds to synthesize bioactive secondary metabolites. The present study was carried out to explore the antibacterial activities of different solvents based on its polarity and tested against the Gram positive and Gram negative bacteria. For the phytochemical constituents, in Amphiroa fragilissima positive reactions were noted for alkaloids, reducing sugars, flavonoids and saponins. In Ulva reticulata, positive reactions were noted for alkaloids, phytosterols, flavanoids and saponins. Antibacterial activity of two seaweeds was compared based on the zone of inhibition. The present study concluded that the selected macroalgae are potential sources of bioactive compounds which have a broad spectrum of antibacterial activity
