Phytochemistry and antibacterial activity of extracts of Parkia biglobosa (Mimosaceae) and carissa edulis (Apocynaceae)

Parkia biglobosa (Jacq) Benth (Mimosaceae)and Carissa edulis (Apocynaceae)are two herbs that have been used traditionally for various conditions including hypertension and microbial diseases. Herbal remedies are an alternative in primary care systems and thus, a promising way for the development of traditionally improved medicines. We had studied in the present work the phytochemistry and anti-microbial activity of these two plants used in traditional medicine. We prepared the two hydro ethanolic extracts from the powdered dried leaves of these plants and the crude extract yields are 20% and 17% respectively. We then fractionated the hydro ethanolic extracts obtained by the liquid-liquid extraction method and assayed the flavonoids and polyphenols by the colorimetric and FolinCiocalteu methods in these different fractions and then tested the hydro ethanolic extracts and fractions on four reference microbial strains (Escherichia coli ATCC 25922; Salmonella typhi ATCC 14028; Staphylococcus aureus ATCC 25923; Pseudomonas aeruginosa ATCC 27853). The results showed us that the polar fractions are very rich in polyphenols, which confirms the results obtained during the phytochemical screening; and these fractions have a more interesting bactericidal activity than the crude extracts (hydro ethanolic). These plants could be an alternative in primary care systems for microbial infections.