Antibacterial Activity of Bidens pilosa Extracts on Escherichia coli O157: H7 Isolated from Apparently Healthy Individuals

This study was carried out to isolate Escherichia coli O157:H7 from fecal samples of children within the age range of 0-5 years from Mother and child hospital, Anchorite daycare, Womens’ forum daycare and FUTA daycare all in Akure, Ondo State. It is also aimed at extracting the bioactive component of the palnt using different solvents and determining the efficacy of the plant extracts on the bacterium by agar well diffusion and evaluating their minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC). The strain showed a high frequency of single or multiple drug resistance (MDR) to the antibiotics tested. The phytochemical screening of the extracts revealed various constituents which include: flavonoid, alkaloid, phenol, saponin, terpenoid, cardiacglycoside and tannin, 70% ethanol, cold water and chloroform were employed for the plant extraction. The ethanol extract of the plant was more potent, showing higher zone of inhibition, followed by water extract and the chloroform extract showed no zone of inhibition. The MIC exhibited was 50 mg/mL, 70 mg/mL for ethanol and 100 mg/mL and 120 mg/mL for water, and also the MBC exhibited was 70 mg/mL, 110 mg/mL, 150 mg/mL for ethanol and 140 mg/mL, 160 mg/mL and 200 mg/mL for water. The result suggests that the preparation of the plant exhibited significant in- vitro antibacterial activity against the bacterium and may be employed for the routine treatment of this infection as an alternative to antibiotics.