Abstract
Background::
Endophytic bacteria produce various bioactive secondary metabolites, which
benefit human health. Tamarindus indica L. is well known for its medicinal value in human health
care. Several studies have reported on its biological effects from various parts of T. indica, but only a
few studies have been devoted to examining the biological activity of endophytes of T. indica.
Objectives:
In the present study, an endophyte was isolated from the leaves of T. indica and screened
for its antimicrobial potential.
Methods:
The selected endophyte was identified by 16s rRNA partial genome sequencing and investigated
for their antimicrobial potency. The preliminary phytochemical tests were conducted for the affirmation
of phytoconstituents in the endophytic crude ethyl acetate extract of T. indica (TIM) and total
phenolic content was performed. The antimicrobial potential of TIM was evaluated against human
pathogenic ATCC gram-positive and gram-negative bacterial strains.
Results:
TIM exhibited an appreciable amount of gallic acid equivalent phenolic content (21.6 ± 0.04
mg GAE/g of crude extract). TIM showed the Minimum Inhibitory Concentration (MIC) at 250 μg/mL
and Minimum Bactericidal Concentration (MBC) at 500 μg/mL among the selected human pathogenic
ATCC strains. At MIC of 500 μg/mL, TIM displayed a significant zone of inhibition against P. aeruginosa
and N. gonorrhoeae.
Conclusion:
The results from our study highlighted for the first time the antimicrobial potential of endophytic
bacterial strain Bacillus velezensis in T. indica leaves and it could be further explored as a
source of natural antimicrobial agents.