Isolation, Identification and Analysis of Novel Metabolites from Soil Samples (Microbial Co Culture) of Cardamom Plantations Western Ghats, India

Abstract

Growing microbial resistance in clinically important microorganisms are of immediate interest in the field of pharmaceutical research. Plants, animals and microbes have been source of various antibiotics for decades. Research on these aspects is extensive and newer compounds have been identified from both terrestrial and marine sources. In recent times, there is emergence of co-culture technique that has proved to produce novel compounds due to the stress induced activity when two strains are grown in the same medium with competition for survival. Studies have shown successful outcomes in co-culture of organisms of the same species including Bacteria-Bacteria, Fungi-Fungi and Fungi-Bacteria. This study aimed at isolating specific microbes from the soil of Cardamom plantation from the Western ghats and obtaining pure culture of Pseudomonas sp. The isolated strains were subjected to morphological and molecular characterization by 16s rRNA sequencing. These strains were further co cultured as a combination to isolate the stress induced metabolites that would be produced due to competition. The extraction and the isolation of the crude metabolite from the co-culture were further evaluated for antimicrobial activity against human pathogenic bacteria. The study revealed the isolation and species identification of bacterial strains Pseudomonas nitritireducens and Micrococcus endophyticus from the soil samples. The co-cultured bacterial strains on extraction by organic solvents of hexane and dichloromethane showed promising activity against both gram positive and gram-negative bacteria on comparison with the other extracts. Further qualitative analysis revealed the presence of saponins and alkaloids in the active extracts.