Isolation, identification and bioactive potential of bacterial endophytes from Coleus

Abstract

Coleus (Lamiaceae) is a large and widespread genus comprising of species with diverse ethnobotanical uses. In the present study, bacterial endophytes were isolated from Coleus forskohlii and Coleus aromaticus. Endophytes are the microorganisms which reside within the plants without showing any harmful effect on its host. Diverse types of endophytes live symbiotically within almost all plants and in turn help the plant in a number of ways such as imparting resistance against biotic and abiotic stresses, producing compounds involved in attraction of pollinators, inducing the plant defense mechanisms, etc. The bacterial endophytes isolated in this study, were characterized by microscopic examination (using gram staining) and molecularly identified by sequencing the 16S rRNA. Extracts were prepared from endophytic biomass using solvents of different polarities (methanol, ethyl acetate and butanol) and were screened for their bioactive potential (in vitro cytotoxicity anti-microbial, and anti-oxidant activity). Scale-up of endophytes showing promising results is under process, which will help in isolation of pure compounds.