Antibacterial activity of Streptomyces Gelaticus isolated from Iraqi soils

الملخص EN

A total of 102 soil samples were collected from different sites in Babylon province, Iraq during the period from May to August 2010.

According to morphological and biochemical tests, twenty isolates of actinomycetes were recovered and finally identified as Streptomyces species (19.6 %) of which 4 isolates were belong to Streptomyces gelaticus which represent (20 %) of all Actinomyctes organisms.

The cultural characteristics of Streptomyces gelaticus isolates showed that the color of aerial mycelium was grey, substrate mycelium was yellowish brown to green with no pigmentation on YMD agar medium, and no melanin production.

The antibacterial activity of S.

gelaticus SAM 10 isolate against three pathogenic bacterial species; Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, was assessed using well diffusion method.

The inhibition zone diameter for S.

aureus was 19.9 mm while it was 10 mm for both of E.

coli and P.

aeruginosa respectively.

The present study represents the first record of isolation of Streptomyces gelaticus in Iraqi soil.