Assessment of Antimicrobial Activities of Sida Acuta, Dioscorea Bulbifera and Citrus Aurantifolia Extracts on Selected Bacteria (Salmonella Typhimurium, Escherihia Coli 0157:H7 and Vibrio Cholerae)

Abstract

Medicinal plants are the primary source of medication used as complementary or alternative treatments to orthodox medicine. The assessment of the effects of plants, Dioscorea bulbifera (Air potato), Sida acuta (wired weed) and Citrus aurantifolia (Lime juice) extracts on selected bacteria (Escherichia coli0157:H7, Salmonella typhymurium and Vibrio cholerae) were investigated. The study area was Omuanwa in Ikwerre Local Government Area of Rivers State, Nigeria were the plants were collected. The test organisms were identified by polymerase chain reaction technique, while the antimicrobial effects of the plant extracts were examined against the different bacterial species by agar well diffusion method and sensitivity interpreted in accordance with the Clinical and Laboratory Standard Institute. Phytochemicals extracted were Flavonoids, Cardiac Glycosides, Tannin, Phenols, Alkaloids, Steroids, Terpenoid and Saponins, however, the concentrations of phytochemicals extracted by ethanol and aqueous showed statistical significant difference of p<0.05. The organisms were more sensitive to Citrus aurantifolia with 83.3%, followed by Sida acuta with 75.0% and Dioscorea bulbifera with 41.7%, also evident in the mean zones of inhibitions of the plant extracts, as the highest mean of 16.333mm was observed in Citrus aurantifolia against all test organisms followed by Sida acuta (15.083mm) and Dioscorea bulbifera (8.583mm). Escherichia coli0157:H7 was most sensitive to Sida acuta, Salmonella typhimurium was most sensitive to Citrus aurantifolia, while Vibrio cholerae showed equal-high sensitivity to Sida acuta and Citrus aurantifolia. Considering different percentage concentrations of plant extracts of 100%, 75%, 50% and 25% against the test organisms, the mean zone of inhibitions was in the order of increasing concentrations, the higher the concentrations the higher their zones of inhibition. The ability of the plant extracts to have shown cleared zone of inhibitions in this research showed the extracts to be potent antimicrobials against these test organisms.