Analyzing the Efficacy of Different Formulations of Camellia sinensis L

Camellia sinensis L., also referred as Green tea is acclaimed as a therapeutic substance and has notable in vitro antimicrobial activity. The purpose of this investigation was to evaluate the antibacterial activity of green tea extracts in different formulations- ethanolic, concentrated, Dimethyl sulfoxide (DMSO), and aged (old) against two pathogenic bacteria, Escherichia coli and Staphylococcus aureus, through a disk diffusion assay using Mueller Hinton Agar plates. The inhibition zones were measured and compared as part of the antimicrobial activity assessment of each of the extracts. The inhibitory zone of the ethanolic green tea extract against Escherichia coli was the largest, followed by old and concentrated one, while there was no observable activity in the extract prepared in DMSO. Contrary to the results against E. coli, concentrated green tea extract exhibited highest antimicrobial measure against Staphylococcus aureus, whereas old and ethanolic extracts showed medium and equivocal activity respectively. Overall, these data imply that the activity of Camellia sinensis extracts is dependent on both the mode of extraction and the bacterial strain targeted. Thus, the study determined to extract green tea phytochemicals in ethanol with antimicrobial activity appropriate against a Gram-negative bacterium like E. coli, and concentrated extract was appropriate against a Gram-positive bacterium like S. aureus. The aged extract also maintained substantial bioactivity, and demonstrates the antimicrobial phytochemicals have high persistence in green tea. This research highlights the potential use of green tea extracts as natural antimicrobial agents for pharmaceutical and food preservation applications. It also highlights the need to optimize extraction methods and storage conditions accordingly to potentialize the bioactive capacity.