Antibacterial Activity of Black Tea on some Selected Bacteria

The antibacterial potential of black tea (Lipton® and Highland tea) on some pathogenic organisms including Staphylococcus aureus, Streptococcus species, Escherichia coli and Klebsiella specie using agar well diffusion technique was investigated. The result showed that the aqueous extract of black tea contains bioactive compounds that are active against all the tested organisms. Lipton tea extract showed maximum inhibition zones of 34 mm against Staphylococcus aureus, followed by Streptococcus sp. with 32 mm, E. coli had 20 mm while Klebsiella sp was the least with 18 mm. Also, Highland tea extract showed zones of inhibition of 21mm, 20 mm, 19 mm and 14 mm on Staphylococcus aureus, Streptococcus sp., E. coli and Klebsiella sp. respectively. Additionally, Lipton tea extract was observed to have more potency on all the organisms used in this study when compared to that of Highland tea. However, there was no significant difference between the two brands of black tea (p>0.05). Hence, individuals are encouraged in daily intake of black tea especially Lipton® and extracts from such teas should be used in the formulation of therapeutic agents against the diseases caused by these organisms under study. Keywords: Antibacterial activity, Aqueous extract, Black tea, Diseases, Pathogenic organisms.