Pharmacological Evaluation of Commercially Available Black Tea And Green Tea For Anti-Bacterial Activity

Dr.E.Padhmapriya, Jayashree, Shruthi E, Saminathan C

Aim:- The aim of the study is to evaluate the anti-bacterial activity of commercially available black tea (Thea sinensis) and green tea (Camellia sinensis).Materials and methods:- Commercial green tea and Black tea were obtained from super market 10g of each were extracted separately by soaking in 100 ml of distilled water for two days. the samples (two concentration 50µg & 100µg) positive and the negative controls were added to each well aseptically by Kirby Bauer Agar well diffusion assay method. This procedure was repeated for each Petri plates then the petri plates were incubated at 37˚C for 24 hrs. After incubation the plates were observed for the zone of inhibition. Result and discussion:- In this study, the prepared sample was tested to identify the pharmacological activity. During this study two bacteria were isolated. The isolated bacteria were determined by gram staining. Two different bacteria identified were staphylococcus aureus, Escherichia coli. The inhibition zone was developed around the disc was measured. From the result, Black tea extracts exhibit greater antimicrobial activity in S. Aureus, while in green tea extracts exhibit its highest activity against E. coli strains. The zone of inhibitory concentration for Black tea and Green tea is effective for S.Aureus and E.coli which were found to be at higher100µl concentration when compared to50µl concentration. This study also shows that the Black tea extract gives the highest zone of inhibition against S. aureus, while green tea extract shows the highest activity against E. coli strains. Conclusion:-The present study concluded that black tea and green tea extracts both shows strong inhibitory effect against Gram-positive and Gram-negative pathogens. From, the result it is noticed that both the teas extract shows strong antibacterial    activity and act as good therapeutic agents to fight against the infection.

Keyword: Zone of inhibition, E.coli, S.aurea, Green tea, Black tea