The antimicrobial activities of ethanolic and hexane extracts of nine species of marine macroalgae collected in the intertidal zone of the San Francisco beach, Ancón, in Lima, Peru were evaluated. It was performed in vitro against a panel of standard Gram-positive bacteria (Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633 and Enterococcus faecalis ATCC 51922) and Gram-negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 9027 and Salmonella Typhimurium 14028). The ethanolic extracts were of higher yield (67%) compared to hexanes (33%), especially against the Gram-positive, being the extract obtained from Ulva enteromorpha var. intestinalis and U. nematoidea the most efficient against S. aureus ATCC 6538 (74.1 and 78.2% inhibition, respectively). The ethanol extracts of Cladophora sp and U. nematoidea against B. subtilis ATCC 6633 showed moderate to low inhibitio...

The antimicrobial activities of ethanolic and hexane extracts of nine species of marine macroalgae collected in the intertidal zone of the San Francisco beach, Ancón, in Lima, Peru were evaluated. It was performed in vitro against a panel of standard Gram-positive bacteria (Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633 and Enterococcus faecalis ATCC 51922) and Gram-negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 9027 and Salmonella Typhimurium 14028). The ethanolic extracts were of higher yield (67%) compared to hexanes (33%), especially against the Gram-positive, being the extract obtained from Ulva enteromorpha var. intestinalis and U. nematoidea the most efficient against S. aureus ATCC 6538 (74.1 and 78.2% inhibition, respectively). The ethanol extracts of Cladophora sp and U. nematoidea against B. subtilis ATCC 6633 showed moderate to low inhibitio...