Isolation, Characterization and Antimicrobial Activities of Leaf and Stem extracts of Guiera Seneglensis

Abstract

Guiera senegalensis is a medicinal plant used in Northern Nigeria for the treatment of malaria, acute gastroenteritis, leprosy and  dysentery. The powdered leaves and stem was soaked in methanol for 72 hours with constant stirring. This was fractionated using  modified kupchan method to obtain various fractions. Preliminary phytochemical screening of the fractions was carried out. The  antimicrobial activity of the n-hexane, ethyl acetate and methanol fractions were investigated in vitro at various concentrations using  agar well diffusion method. Preliminary phytochemical result for leaves and stem revealed the presence of tannins, terpenoids,  flavonoids, alkaloids, anthraquinones, cardiac glycosides and phlobatannins. The antimicrobial activity of the fractions against ten  pathogenic organisms revealed moderate to good inhibition for Escherichia coli, Pseudomonas aeruginosa, Streptococcus pneumoniae  and Candidas albicans. The minimum inhibitory concentration of fractions was determined using broth dilution method. The lower MIC  value (12.5 mg/mL) was exhibited by the aqueous methanol and ethyl acetate fractions. With the help of HNMR, HQSC and CNMR which  led to the isolation and characterisation of a proposed compound named β-sitosterol.