A Preliminary Study on Antimicrobial Activities of Some Bacteria Isolated from Marine Environment

Abstract

A survey of antibacterial and/or antifungal substance producing bacteria from neritic seawater and sediments, and extraction of the activity with different organic solvents were carried out. From eighty-eight strains of isolated bacteria only fifteen were found to have antimicrobial activity, some against Pseudomonas sp. that are highly resistant to current antibiotics. The Corynebacterium-Arthrobacter group accounted for 30.7% of the strains isolated and 46.7% of those with antimicrobial activity. Only one of the fifeen antimicrobial strains produced pigment. Production of antimicrobial substances varied with the culture medium and the screening tests used (disc and plate diffusion). Of three organic solvents of differing polarity used sequentially to extract the active principles from the 15 active strains, ethyl acetate was the most efficient; none of the solvents used extracted substances with antifungal activity. © 1991, The Japanese Society of Fisheries Science. All rights reserved.