Preliminary studies of marine microorganisms on antimicrobial activity

The 1003 strains of marine microorganisms, consisting of 520 actinomycetes, 111 fungi, 222 normal temperature bacteria and 150 heat resisting bacteria, were isolated from marine sediment and organism samples collected from the South China Sea,the East China Sea and the Yellow Sea. These strains were screened for antimicrobial active strains using the method of paper disc diffusion. The result showed that 321 strains of marine microorganisms (about 32.0% of the total isolated strains) had antimicrobial activity. The isolation rates of antimicrobial active strains from actinomycetes, fungi, normal temperature bacteria and heat resisting bacteria were 39.6%,32.4%,17.1%,27.3%,respectively. The proportion of antimicrobial active strains was closely correlated with the sample collection. For marine bacteria, the isolation rate of antimicrobial active strains from organism samples was higher than that from sediment samples. But for marine actinomycetes and fungi, the result showed reverse trend. The antimicrobial spectra of all types of marine microorganisms were greatly different.