Antibacterial activity and phytochemical composition of crude acqueous, ethanolic and methanolic extracts of leaves and seeds of rotheca myricoides against selected enteric gram negative bacteria isolated from diarhoeic children attending Mulago National Referral Hospital

Abstract

Background Rotheca myricoides, commonly called blue glory bower or blue butterfly bush, is a suckering evergreen shrub with a somewhat open habit which grows rapidly to 6-10' tall and as wide in its native habitat but more typically to 2-4’ tall in containers. It is native to tropical eastern Africa (Kenya and Uganda). It is also found in other African countries such as Angola, Botswana, Namibia, Burundi, DRC, Rwanda, Ethiopia and South Africa. This shrub was formerly known as Clerodendrum myricoides. It is used as animal feed and also used to treat various gastrointestinal disorders and other conditions such as cancers etc. Studies have shown that this is possible due to different phytochemicals that compose this plant. Methods The current study was aimed at determining the antibacterial activity and phytochemical analysis of the Rotheca myricoides plant extracts against selected gram negative bacteria. The aim of the study was to evaluate the antibacterial activity of both leaf and seed aqueous, methanol and ethanol extracts against selected gram-negative bacteria pathogens notably E. coli and S. species. The antibacterial activity was carried out by agar well diffusion technique against the bacterial pathogens and the zone of inhibition was measured in mm diameter and minimum inhibitory concentration was calculated on every organism. Results In the study, Rotheca myricoides extract was found to be effective on the all organisms tested. In leaf extracts, the highest zone of inhibition was 20.25+_1.89mm and highest minimum inhibitory 0.125g/ml for E. coli and 28.50+_0.29mm and highest minimum inhibitory concentration of 0.063g/ml for S. species. In seed extracts the highest zone of inhibition was 18.34+_1.70mm and the highest minimum inhibitory concentration of 0.125g/ml for E. coli and the highest zone of inhibition of 23.63+_0.24mm and the highest minimum inhibitory concentration of 0.125g/ml for S. species.