Isolation and characterisation of bioactive compounds from leaf extract of combretum lamprocarpum (diels)

Combretum lamprocarpum,is a plant used in tropical and sub Saharan parts of Africa in the treatment of wounds, stomach ache, diarrhoea, and vomiting. The dried powdered plant material(leaves) was extracted using a microwave-assisted extraction technique.Phytochemical and antimicrobial screening of the extracts were carried out using standard methods.The compound was purified using conventional chromatographic techniques and characterised using spectroscopic techniques. The phytochemical screening of the extracts revealed the presence of steroids, terpenes, alkaloids, carbohydrates, saponins, tannins, cardiac glycosides and flavonoids. The antimicrobial screening of the crude extracts showed that all the extracts had significant activity against microbes with the exception ofhexane extract. The diameter of the zone of inhibition ranged between 12 and 29 mm, the minimum inhibitory concentration ranges between 3.13 and 50.00 mg/ml. The minimum bactericidal concentration/minimum fungicidal concentration was between 6.25 and 50.00 mg/ml. A bioactive triterpene coded K1, was isolated as a white crystalline compoundfrom the ethyl acetate extract and characterised using FT-IR, 1H-NMR, 13C-NMR analysis as lupeol. The isolated compound from the ethyl acetate extract was found to be active

againstStaphylococcus aureus(MBC=25.00μg/ml), Salmonella typhi(MBC=12.50μg/ml), Escherichia coli(MBC=6.25μg/ml),and Pseudomonas aeruginosa (MBC=12.50μg/ml). The structure of the compound was supported by comparing the experimental spectroscopic data with that of literature. In conclusion, thisstudy revealed that the leaves ofCombretum lamprocarpumhasa potent medicinal value. The chloroform and methanol extracts showedbioactivity and therefore, should be studied for possible bioactive compounds.