Antibacterial Activities of Vernonia Amygdalina Extracts against Salmonella Typhi

Abstract: Background: Plant extracts, used alone or in combination, were used as a traditional and local means of treatment for both infectious and non-infectious disorders long before the revolutionary discovery of medications that could block bacterial activity. This is aimed at determining the potentials of Vernonia amygdalina leaf extracts, its phytochemicals, and antibacterial activities against pure isolate of Salmonella typhi obtained from cultured plate media. Methods: An experimental study was carried out in the Microbiology Laboratory at the Bingham University Karu, Nasarawa State. Salmonella Typhi Samples were isolated and collected from selective cultured media (SSA) in the laboratory for microbiological analysis. Specified concentrations of Vernonia amygdalina extract was obtained from the powdered leaf by subjecting it to aqueous and ethanol extraction. The extracts were used to determine their antimicrobial activities against the Salmonella Typhi isolate. Results: The test results revealed the presence of various phytochemicals, such as flavonoids, alkaloids, saponins, and tannins in the extract. The Aqueous extract demonstrated activity against S. typhi, with growth inhibition zones measuring from 6.0±0.1mm at 62.5mg/ml to 18.0±1.2mm at 500mg/ml. In comparison, the Ethanolic extract showed growth inhibition zones ranging from 4.0±0.1mm at 62.5mg/ml to 22.0±1.5mm at 500mg/ml against S. typhi, while Amoxicillin, serving as the control antibiotic, inhibited growth with zones ranging from 2.0±0.2mm at 31.25mg/ml to 30.0±1.0mm at 500mg/ml against S. typhi. Conclusion: It was discovered that the plant extracts killed the organism with MBCs of 250 mg/ml for the ethanolic extract and 500 mg/ml for the aqueous extract, and that they inhibited the development of the test organism with a MIC of 250 mg/ml for both aqueous and ethanolic extracts. According to the concentration employed, this suggests that the extracts may be bacteriostatic or bactericidal. The findings showed that crude extracts of Vernonia amygdalina were just as effective as traditional antibiotics.