The search for alternative medicine for the treatment of pathogenic organisms associated with urinary tract infection (UTI) is on increase. The study was carried out to determine the antimicrobial activities of Ocimum gratissimum leaf extracts on three urinary tract pathogens; Escherichia coli, Staphylococcus aureus and Candida albicans, using their corresponding standard oganisms as controls. The phytochemical analysis of aqueous and alcoholic contents of Ocimum gratissimum leaf extracts revealed the presence of; alkaloids, carbohydrates, flavonoids, glycosides, phenolics, saponins, steroids, and tannins. The minimum inhibitory concentration (MIC), minimum bacteriostatic concentration (MBC) and minimum fungustatic concentration (MFC) of the extracts tested on the three uropathogens was 62.5 to 125 mg/ml. The ethanolic extracts at the concentration of 500mg/ml exhibited strong activity against the urinary pathogens with maximum zones of inhibitions of 23.5±1.5, 23.6±0.6 and 18.25±1.3mm while the aqueous extracts at the same concentration showed weak antimicrobial activity at 3.5±0.5mm as the highest zone of inhibition and 1.4±0.0mm as the lowest zone of inhibition. Notably, the inhibition zones increased with increase in extracts concentration and decreased with decrease in the concentration of extracts. Meanwhile, 12 fractions were eluted from O. gratissimum leave extract. The major phytochemical fractions were mainly alkaloids, flavonoid, and saponins. This study showed that the ethanolic extracts of Ocimum gratissimum is a good antimicrobial agent in-vitro and should not be neglected as an alternative medicine for treatment of pathogenic UTIs.
Keywords: UTI, Uropathogens, Ocimum gratissimum, Antimicrobial, Alternative medicine.