Antibacterial attributes of extracts of Phyllantus amarus and Phyllantus niruri on Escherichia coli the causal organism of urinary tract infection

In view of the prevalence of urinary tract infection (UTI) worldwide, the increasing resistance of pathogenic bacteria to conventional antibiotics and their side effects, the aerial part and root of Phyllanthus amarus (Schum. and Thonn.) and Phyllanthus niruri (L.) were analysed for mineral and phytochemical constituents, and their ethanol extracts screened against five clinical isolates of Escherichia coli associated with UTI, to ascertain their effectiveness in UTI treatment, and provide basis for future clinical trials of the two plants. The isolates (10-1 × 10-6 cfu/ml) were tested against ethanol extracts (10 mg/ml) of plant parts using agar well diffusion method. Phytochemical and mineral analyses of the plant samples were done using standard protocols and all data were statistically analysed. The quantities of various phytochemical compounds and minerals were significantly (P<0.05) higher in P. niruri than P. amarus. At 10-6 cfu/ml inoculum concentration of all isolates, the inhibitory activities of extracts of P. amarus and P. niruri were the same, and significant (P<0.05) against isolates EC01, EC02, EC04 and EC05 compared to the control experiment. The inhibitory pattern varied against EC03, extract B (29.00 mm) was the most active, followed by extract C (24.00 mm), and extracts A and D gave the same diameter (19.00 mm) of inhibition. The two plants showed significant antibacterial activity against isolates and could be good alternatives to chemical antibiotics in the treatment of E. coli related UTI, however the mechanism of action of the plant extracts in treatment should be investigated.   Key words: Antibacterial activity, E. coli, Phyllanthus amarus, Phyllanthus niruri, urinary tract infection.