Phytochemical and Antibacterial Properties of Leaf Extracts of <i>Ipomoea asarifolia</i>

Abstract

The antibacterial potency of aqueous and methanol extracts of Ipomoea asarifolia leaves; a plant widely used by traditional medical practitioners in Nigeria was determined in vitro against three bacterial pathogens (Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa) by agar well diffusion method. The pattern of inhibition varied with the extracts and the organisms tested. Both the aqueous and methanol extracts were potent on E. coli and S. aureus with maximum zone of growth inhibition of 21mm and 20mm at 200mg/ml respectively Pseudomonas aeruginosa was resistant to both extracts at all the concentrations tested. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) against E. coli for aqueous extract were 50mg/ml and 100mg/ml respectively; and 100mg/ml and 200mg/ml for methanol extract respectively. Similarly, The MIC and MBC against S. aureus for aqueous extract were 100mg/ml and 200mg/ml; 200mg/ml for the methanol extract. Preliminary phytochemical screening reveal the presence of anthraquinones, saponins and tannins in both aqueous and methanol extracts; triterpenes, flavonoids and glycosides were found only in the aqueous extract while alkaloids were found only in the methanol extract. However, carbohydrate and steroids were absent in both extracts. The spectra of activities shown by the extracts could be attributed to the presence of these phytochemicals which signifies the potential of I. asarifolia as a source of therapeutic agents. These findings therefore, justify the traditional medicinal use of the plant.

Keywords: Ipomoea asarifolia, phytochemical, antibacterial potency, bacterial pathogens

Nigerian Journal of Basic and Applied Science (2011), 19 (2): 236-240