Production and Characterization of Bioactive Secondary Metabolites from Streptomyces species Associated with Roots of Leguminous Plants

Abstract

The antibiotics are an important component of the chemotherapeutic agent to treat infections caused by infectious microorganisms in human beings and animals. The most of pathogens causing diseases in humans and animals have developed resistance against antibiotics drugs. Therefore the effectiveness of antibiotics is decreasing. To treat antibiotic-resistant pathogenic microorganisms and to obtain potent broad-spectrum antibiotics, Streptomyces species from unique ecological niche will be a promising candidate. Hence in the present study Streptomyces species from the rhizospheric area of legume plants viz. soybean, gram, ground-nut and pigeon-pea have been isolated and screened for antimicrobial activity against pathogenic bacterial and fungal species. The Streptomyces species efficient in antibacterial and antifungal activity have been identified as Streptomyces rochei, Streptomyces luteus and Amycolatopsis orientalis by using conventional and molecular biology approach. The bioactive antimicrobial compound produced by Streptomyces rochei was purified by using liquid-liquid extraction and chromatographic techniques. The purified compound was identified as Fatty Acid Methyl Ester (FAME) viz. n-Hexadecanoic Acid Methyl Ester. The n-Hexadecanoic Acid Methyl Ester obtained from Streptomyces rochei have shown antimicrobial activity against bacterial and fungal pathogens viz. Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus, Vibrio parahaemolyticus, Aspergillus niger, Candida albicans, Fussarium oxysporum and Saccharomyces cerevisiae as well as cytotoxic activity against MCF-7 cancer cell lines. The Streptomyces rochei isolated from rhizospheric area of leguminous plants have ability to produce n-Hexadecanoic Acid Methyl Ester in a fermentation medium. n-Hexadecanoic Acid Methyl Ester have both antimicrobial and antitumor activity in vitro. The n-Hexadecanoic Acid Methyl Ester will be a potential bioactive molecule to treat infectious diseases cau