In vitro antibacterial efficacy of plants used by an Indian aboriginal tribe against pathogenic bacteria isolated from clinical samples

Abstract

Abstract Objectives To evaluate antibacterial efficacies of 21 medicinal plants used by an Indian aboriginal tribe against infectious diseases caused by bacteria isolated from clinical samples. Methods Standard biochemical procedures were followed for identifying bacteria that were isolated from several clinical samples. All of the bacterial strains were subjected to antibiotic sensitivity tests by Kirby–Bauer's disc diffusion method. From antibiograms of isolated Gram-positive and Gram-negative bacteria, it was discernible that samples were multidrug resistant (MDR). The methanol leaf-extract of Solanum xanthocarpum was subjected to thin layer chromatography (TLC) for phytochemical analysis. Molecular docking of β-lactamase enzyme of Escherichia coli with phytochemicals of S. xanthocarpum was performed to locate effective compounds. Results The most effective 5 plants, which caused the size of the zone of inhibition to range from 21 to 27 mm, were Buchanania latifolia, Careya arborea, Ocimum tenuiflorum, Senna alata and S. xanthocarpum, for MDR bacteria. S. xanthocarpum had the lowest MIC value of 0.67 mg/ml and the lowest MBC value of 1.51 mg/ml against E. coli . In the TLC study, 9 spots of methanol leaf-extract of S. xanthocarpum were recorded with two solvent systems. The phytochemicals of S. xanthocarpum, solasodine and stigmasterol glucoside had the highest docking score values, −10.868 kcal/mol and −10.439 kcal/mol, respectively, against β-lactamase. Conclusion This study could prove in vitro antimicrobial efficacy of 5 uncommon plants against MDR pathogenic bacteria. Solasodine and stigmasterol glucoside were computationally recorded as the best controlling chemicals from the plant S. xanthocarpum.