Bioactive Endophytic Actinomycetes of Cinnamomum sp.; Isolation, Identification, Activity Guided Purification and Process Optimization of Active Metabolite

Abstract

Studying on endophytic actinomycetes of Cinnamomum sp. from Indian rainforest, Cherapunji, one of our isolated strains designated as CH1 was found to produce significant antibacterial activity against test pathogens (Aeromonas caviae (ATCC 15468), Vibrio parahemolyticus ATCC 1782, Pseudomonas aeruginosa (ATCC 9027), Proteus vulgaris (ATCC 12453), Shigella flexnerii (ATCC 12022), Escherichia coli (human sample isolate), Bacillus subtilis (ATCC 11774) and Bacillus cereus (ATCC 14579). Scanning electron microscopic studies, morphological characterization and 16s ribosomal RNA gene sequence based classification strongly suggest that the isolate is a new strain of Streptomyces rochei. The rRNA gene sequenced was submitted to NCBI (GenBank accession number KJ486840.1). An antibacterial metabolite was extracted from fermented culture broth and purified by repeated silica gel column chromatography. TLC and bioautogram study of active fraction showed compound of Rf 0.196 was active metabolite where as HPLC study showed two major peak of RT 2.433 and 2.632 min. Parameters influencing optimal antimicrobial production were also determined and the active compound was found nonmutagenic by Ames test. Based on above experiments it is concluded that this entophytic isolate can be further exploited for industrial and biological applications.