Antagonistic Endophytic Bacteria as a Promising Source of Bioactive Secondary Metabolites
Keywords:
Endophytes, Abrus precatorius, antagonistic, Pseudomonas parafulva, Bacillus mycoidesAbstract
The continuous demand for novel bioactive compounds has intensified the exploration of natural sources, particularly for applications in pharmaceuticals and agrochemicals. Among these, endophytic bacteria that reside asymptomatically within plant tissues have emerged as a significant and underexplored reservoir of diverse bioactive secondary metabolites. The present study focuses on the isolation and characterization of antagonistic endophytic bacteria from Abrus precatorius. It is a medicinally important plant commonly known as Gunja, belonging to the family Fabaceae and is recognized for its broad spectrum of therapeutic properties. Endophytic bacterial isolates were obtained from leaf tissues of Abrus precatorius using standard surface sterilization and microbiological culturing techniques. Among the isolates obtained, two bacterial strains exhibited antagonistic relationship. They were identified as Pseudomonas parafulva and Bacillus mycoides. Pseudomonas parafulva exhibited significant antagonistic activity against Bacillus mycoides, as evidenced by inhibition of its growth in vitro. This antagonistic interaction suggests the production of bioactive secondary metabolites with potential antimicrobial properties. The findings highlight the role of endophytic bacteria associated with medicinal plants as promising candidates for the discovery of novel bioactive compounds. Overall, this study underscores the importance of bioprospecting endophytic bacterial communities from medicinal plants such as Abrus precatorius and supports their potential application in the development of new antimicrobial agents.
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