Abstract

STUDIES ON SECONDARY METABOLITES OF STREPTOMYCES SPECIES CONTAMINATED BACTERIA

Aurpita Shaha*, Ariful Haque and Anwar Ul Islam

ABSTRACT

Three marine soil strains of actinomyces were contaminated by Bacillus species designated as AIAS-5, AIAS-10 and AIAS-39 with spontaneous mutation during repeated transfer on slants media ( storage at 4°C ). Co-culture designated as AIAS-510, obtained from AIAS-5 & AIAS-10 and co-culture of AIAS-10 and AIAS-39 designated as AIAS-1039, results in the production of a new compound which were not found in their control culture. Antibacterial activities of AIAS-5, AIAS-10 and co-culture AIAS-510 were performed against a series of pathogenic bacteria. The results showed that co-culture AIAS-510 was highly active against a series of gram- positive and gram-negative bacteria compare to monoculture AIAS-5 and AIAS-10 alone. Crude extract of co-culture AIAS-1039 obtained from culture of AIAS-10 & AIAS-39 and crude extracts of AIAS-10 & AIAS-39 monoculture was also investigated for their biological activities. Antibacterial activities of AIAS-10, AIAS-39, and AIAS-1039 were performed against a series of pathogenic bacteria. The results showed that monoculture AIAS-10 was highly active against a series of gram-positive and gram-negative bacteria compare to monoculture AIAS-39 and co-culture AIAS-1039. Although antibiotic production was not induced in co-culture but antifungal activity was induced significantly. Co-culture AIAS-510 was more active against pathogenic fungi than monoculture AIAS-5 and AIAS-10. The Minimum Inhibitory Concentrations (MIC) of co-culture AIAS-510 was determined using broth-dilution method and found to be in the range of 16-32 μg/ml against a wide range of pathogenic bacteria.

Keywords: Actinomyces strain; co-culture; inhibitory; antifungal & antibacterial.