Abstract

Antimicrobial Activity of Aqueous Extracts of Maytemus putterlickoides, Senna spectabilis and Olinia usambarensis on Selected Diarrhea-Causing Bacteria

Mugweru FG, Nyamai DW, Arika MW, Ngugi MP, Gathumbi PK, Njagi ENM and Ngeranwa JJN

Diarrhea is one of the leading causes of morbidity and mortality among children under the age of five years in the developing world. Opportunistic bacteria have been identified as the major cause of diarrhea in HIV infected patients. Treatment of these emerging and re-emerging strains of diarrhea causing bacteria has become difficult due to their increased tolerant to the present available antibiotics. There is need to identify and develop alternative drugs, which are effective, affordable and easily accessible to diarrhea patients. However, there is no record in the literature of the antibacterial activity of these plants. The objective of this study was to enhance understanding of the efficacy of ethno-medical materials in the management of diarrhea. Antibacterial activity was evaluated by determination of Minimum Inhibition Concentration and the Minimum Bactericidal Concentration of the plant extracts against the diarrhea causing bacterial. Phytochemical screening for bioactive compounds was undertaken using standard qualitative methods. Maytenus putterlickoides (roots) and Senna spectabilis (leaves) were active against Salmonella typhi, Shigella flexineriae and Shigella Dysenteriae with zone of inhibition ranging 9.2-15.8 mm. Olinia usambarensis (leaves) had antimicrobial activity against several bacterial isolates with zone of inhibition ranging 9-15 mm. Alkaloids, tannins, anthrocyanins, triterpenes and steroids, saponins, flavanoids, coumarins and reducing sugars were present in the three plant extracts. These phytochemicals account for the antibacterial activity of the extracts against the bacterial strains.