PHYTOCHEMICAL ANALYSIS AND EVALUATION FOR ANTIMICROBIAL ACTIVITIES OF THE EXTRACTS OF Psidium guajava L. AND Calpurnia aurea (Ait.) Benth, AGAINST SELECTED HUMAN BACTERIAL PATHOGENS

Abstract:

Plants are rich in a wide diversity of secondary metabolites which have been found to exhibit antimicrobial, antioxidant and antitumor activities. Guava (Psidium guajava L., Myrtaceae) and (Calpurnia aurea L. Fabaceae) are known for their traditional medicinal values. These studies were conducted with the objective of analyzing the secondary compounds profile of the two plant species and evaluate their antimicrobial properties on selected human bacterial pathogenes. Extraction was done by maceration using ethanol solvent. Qualitative analysis of phytochemicals was carried out using standard protocols and phytochemicals were quantified from leaf and bark extracts or powders using Spectrophotometric or gravimetric method. Antibacterial activities of leaf and bark extracts were determined by disc diffusion and broth dilution methods. Results of qualitative analysis showed that both plants have tannins, steroids, saponins, terpenoids and alkaloids in their leaves and barks. Whereas flavonoids and phlobatannins were absent in both plants' leaves and barks extracts. There was significant concentration difference between the different types of compounds analyzed from leaves and barks of both plants. Saponins were found to be higher in both P. guajava and C. aurea leaves followed by total terpenoids, alkaloids, total phenols and tannin. In barks of both plants, however, total terpenoids was highest followed by saponins, alkaloids, total phenols and tannins. Each group of compound also varied significantly (P