An evaluative study of the inhibitory activity of the aqueous infusion extract of Camellia sinensis and its impact on the growth of Klebsiella pneumoniae

Abstract

In response to the escalating global concern of antibiotic resistance, there is an urgent need to explore natural alternatives with potent antimicrobial properties. This study aimed to evaluate the antibacterial activity of the aqueous infusion extract of green tea leaves (Camellia sinensis) against the Gram-negative bacterium Klebsiella pneumoniae. Four concentrations of the extract (200, 300, 400, and 500 mg/ml) were prepared and assessed using the disc diffusion method on Mueller Hinton Agar the experiment was repeated three times.

The findings demonstrated a clear concentration-dependent inhibitory effect. The highest antibacterial activity was observed at 500 mg/ml, with a mean inhibition zone diameter of 10.66 mm, whereas the lowest activity was recorded at 200 mg/ml (7.33 mm). These results confirm that the aqueous extract of green tea exhibits significant antibacterial activity against K. pneumoniae. The observed effect is likely attributed to the presence of bioactive polyphenolic compounds, particularly catechins, which are known to disrupt bacterial cell membrane integrity and interfere with essential cellular processes.

The study highlights the potential of green tea extract as a promising natural antimicrobial agent, supporting its prospective application in medical and food preservation fields. Further in-depth investigations are recommended to elucidate the precise mechanisms of action and evaluate its safety and efficacy in practical applications.