Vol. 7 No. 1 (2025): In vitro antibacterial activity of Tamarind (Tamarindus Indica) seed extracts against Staphylococcus aureus and Klebsiella pneumoniae

Despite the discovery of antibiotics, infectious diseases remain a serious concern due to the rise of antibiotic resistance. This situation necessitates the urgent search for alternative antimicrobial agents from various sources. Plants are a priority because of their bioactive components, which have potential in combating multi-drug resistant microorganisms. In Ethiopia, communities have traditionally used the seeds of Tamarind (Tamarindus indica) for wound healing, snake bites, abdominal pain, inflammation, helminth infections, antimicrobial effects, and diabetes management. However, scientific studies on this plant remain limited. This study aimed to investigate the antibacterial effects of Tamarindus indica seed extracts collected from Itang Woreda, Gambella, Ethiopia, against Staphylococcus aureus and Klebsiella pneumoniae. The maceration technique was used for extraction, employing acetone and ethanol as solvents. The antibacterial activity of each extract was evaluated at concentrations of 100, 200, and 300 mg/mL using the disk diffusion method. Pathogenic strains of Staphylococcus aureus (ATCC 25923) and Klebsiella pneumoniae (ATCC 700603) were obtained from the Ethiopian Biodiversity Institute and cultured on selective media. The findings indicated that neither the acetone nor ethanol extracts were effective against S. aureus or K. pneumoniae at any tested concentration. No significant differences were observed between the extracts and the negative control (P > 0.05). However, results were significantly different from the positive control (P < 0.05). These results suggest that Tamarindus indica seed extracts do not exhibit antibacterial activity against the tested bacteria. Further research on other pathogenic bacteria and fungi is recommended for more comprehensive conclusions.

Keywords/Phrases: Antibacterial activity, Disk diffusion, Maceration, Pathogenic bacteria, T. indica