Abstract:
Antimicrobial activities of metabolites of Streptomyces species from termitarium and
grassland soils were studied against some pathogenic microorganisms. Streptomyces species were
isolated from the above soil samples by streak plate technique. The active metabolite was extracted
using chloroform. Optimization of the extracted metabolites was done at different pH, carbon
sources and metal salts. Purification of the extract was performed using column and thin layer
chromatographic techniques. The metabolites (non-purified and purified) produced were screened
for antimicrobial activities against some pathogenic bacteria and fungi using agar well diffusion
method. Antibiotic sensitivity test was also carried out. The Streptomyces species isolated from
termitarium
are
Streptomyces
griseoflavus,
Streptomyces
xanthophaeus,
Streptomyces
viridoflavus, Streptomyces galtieri, Streptomyces albidoflavus and Streptomyces microflavus.
Also, those isolated from grassland soil are Streptomyces rimosus, Streptomyces albus,
Streptomyces fumosus, Streptomyces riseoflavus, Streptomyces spiraiis, Streptomyces flavogriseus
and Streptomyces aureofaciens. During the primary screening, six Streptomyces species,
Streptomyces rimosus, Streptomyces flavogriseus, Streptomyces albus, Streptomyces riseoflavus,
Streptomyces griseoflavus, Streptomyces xanthophaeus showed inhibitory effect against some test
pathogenic bacteria and fungi. The purified metabolite of Streptomyces albus showed high
inhibitory effect on Serratia marcescens and Pseudomonas aeruginosa while Streptomyces
rimosus showed high inhibitory effect on Klebsiella pneumoniae. Also, Streptomyces riseoflavus
showed high inhibitory effect on Staphylococcus aureus. On the antibiotic sensitivity test,
Pefloxacin and Gentamycin showed the highest and least inhibitory effect against all the
pathogenic bacteria respectively. Partially purified metabolites of Streptomyces flavogriseus
compared favourably with known commercial drugs. Streptomyces flavogriseus from grassland area should be exploited in production of antibiotics for treatment of dysentery caused by Shigella
and possibly also methicillin resistant Staphylococcus aureus
