Antibacterial Efficacy of Termanilia catappa (Tropical Almond) Leaf Extracts on Some Selected Clinical Pathogens

Abstract

The antibacterial efficacy of Terminalia catappa (Tropical almond) leaf crude extracts was carried out using agar “well” diffusion method on some clinical pathogens (Staphylococcus aureus and Salmonella typhi) which were obtained from Federal Medical Centre Birnin Kebbi, Kebbi State. The ethanol and aqueous extracts were obtained using ethanol and warm water, as solvents for the extraction respectively. The antibacterial efficacy testing of Terminalia catappa leaf crude extracts indicates appreciable activity against the pathogens with the varying concentrations (10, 30, 50 and 70 mg/ml) used. The phytochemical studies were carried on the ethanol and aqueous crude extracts of Terminalia catappa leaf, in order to ascertain the presence of certain bioactive compounds. The screening revealed the presence of some important bioactive compounds such as alkaloids, tannins, flavonoids, cardiac glycosides and glycosides which could be responsible for the observed efficacy. The varying concentrations of the extracts were introduced to prepared “well” inside the plates, the plates were then incubated at 37⁰C for 24 hours, the zone of inhibition were then measured after the incubation period.  The highest activity of 24.0mm was recorded for the ethanol extract on Salmonella typhi at the highest concentration of 70mg/ml used while the aqueous extract indicates the highest activity of 20.0mm against the two test bacteria at the highest concentration of 70mg/ml used. Ciprofloxacin antibiotic impregnated disc was used for the positive control. The minimum inhibitory concentration and minimum bactericidal concentration study of  both the ethanol and aqueous crude extracts of  Terminalia catappa leaf on the test bacteria indicates that the extracts has both bacteriostatic and bactericidal efficacy. The responses of the test bacteria to the crude extracts of Terminalia catappa leaf and the presence of very important bioactive compounds in the  plant leaf has provided clue of  using the leaf of Terminalia catappa for medicinal remedy against disease caused by the test bacteria under study. Toxicity level of this plant leaf should be determined for safety purpose.

Keywords: Agar well, Antibacterial, Efficacy, Leaf extracts,  Pathogens, Terminalia catappa,