Exploring the Antibacterial Properties of Vernonia amygdalina (Bitter Leaf) Extract: A Potential Alternative to Conventional Antibiotics

David Musyoki

School of Pharmacy, Kampala International University, Uganda


As part of the ongoing search for potent and resistance-free antibacterial medicinal plants, this study aimed to evaluate the antibacterial properties of the plant extract of Vernonia amygdalina, commonly known as bitter leaf. Standard procedures were used to provide a potential cheap alternative to conventional medication for treating bacterial infections. The aqueous extract of V. amygdalina leaves was prepared and subjected to phytochemical screening, which revealed the presence of tannins, phlobatannins, saponins, terpenoids, cardiac glycosides and alkaloids. The antibacterial activity of the extract was tested against the gram-positive bacterium Staphylococcus aureus and the gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli using the agar well diffusion method. The extract showed moderate antibacterial activity, exhibiting 10 mm and 8 mm zones of inhibition against S. aureus and P. aeruginosa respectively at a concentration of 20 mg/ml. However, it displayed no activity against E. coli. In comparison, the standard antibiotic gentamicin produced larger zones of inhibition of 33.5 mm, 27 mm, and 23.5 mm against the respective test organisms. The results suggest that V. amygdalina extract had greater antibacterial activity on the gram-positive S. aureus than on the gram-negative microorganisms tested. The presence of phytochemicals like tannins, saponins and alkaloids in the extract may contribute to its antibacterial properties. Further research is warranted to fully elucidate the medicinal potential of V. amygdalina and isolate the active compounds responsible for the observed antimicrobial effects. Overall, the findings provide a scientific basis for the traditional use of this plant in treating bacterial infections.

Keywords: Vernonia amygdalina, Antibacterial activity, Phytochemicals, Antimicrobial resistance, Traditional medicine

CITE AS: David Musyoki (2024). Exploring the Antibacterial Properties of Vernonia amygdalina (Bitter Leaf) Extract: A Potential Alternative to Conventional Antibiotics. NEWPORT INTERNATIONAL JOURNAL OF BIOLOGICAL AND APPLIED SCIENCES, 5(1): 60-67. https://doi.org/10.59298/NIJBAS/2024/5.1.606711