Estimation of bioactive potential of culturable bacterial endophytes from Coleus

Endophytic microflora is source of several bioactive compounds. Endophytes isolated from Coleus species are yet to be fully explored for their bioactive potential. In this study, bacterial endophytes were isolated from three different species of Coleus. Isolated endophytes were characterized by using Gram staining and by sequencing 16S rRNA region. Further, solvents with different polarities were used to prepare extracts which were used for assessment of different bio-activities including in vitro cytotoxicity, anti-microbial and anti-oxidant activities. Also, the pure endophytic bacterial cultures were evaluated for their antiphytopathogen potential as well as indole-3-acetic acid (IAA) and protease production. Advanced studies on the endophytes with promising activities may lead to the isolation of novel natural products for drugs as well as in industrial and agricultural applications.

Isolation, identification and bioactive potential of bacterial endophytes from Coleus

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.