The minimum inhibitory concentration of the leaf extract was determined by visual observations and it
was observed that the MIC for the bacterial strains was in the range of 25 µg to 100 µg. Concurring with the
disc diffusion results, the MIC of the Proteus vulgaris was found to be least (25 µg) while for Staphylococcus
aureus, Pseudomonas aeruginosa and Klebsiella pneumonia were approximately 40, 35 and 25 µg. To further
bolster the antimicrobial properties of the betel leaf extract, experiments were conducted to study the effects of
the leaf extract on the life cycle of the four bacterial strains, using a time-kill kineics. The life cycle was
determined by plotting a graph between the turbidity of the cell culture (as measured by the spectrophotometer)
and the time duration.