Comparative Studies on the Phytochemical Properties of Five Nigerian Medicinal Plants

Aims: This work investigated the phytochemical composition of five Nigerian medicinal plants and the significance of the phytochemicals with respect to the treatment of diseases were discussed.

Study Design: Fifteen phytochemicals were qualitatively analysed from the plants ethanolic extracts while five out of these were quantitatively determined.

Place and Duration of Study: Department of Biochemistry, Chukwuemeka Odumegwu Ojukwu University, Uli, Nigeria, between July, 2014 and August, 2014.

Methodology: Standard phytochemical analysis methods were adopted.

Results: Preliminary screening of the leaves of Psidium guajava, Azadirachta indica, Carica papaya, the rhizomes of Zingiber officinale and bulbs (cloves) of Allium sativum revealed the presence of alkaloids, tannins, flavonoids, saponins, phenols, steroids, terpenoids and carboxylic acids in all the plants ethanolic extracts. A. indica contained all the phytochemicals except coumarin, while there was the absence of anthraquinone, phlobatannin, and quinone in A. sativum. Phlobatannins was also absent in C. papaya and P. guajava extracts. There was also the absence of anthraquinone and cardiac glycosides in P. guajava and Z. officinale respectively. Resins were not detected in the plants extracts of C. papaya and Z. officinale. The quantitative analysis of the five selected phytochemicals revealed that there was significant difference in the mean values of alkaloids and flavonoids contents of the plants at P<0.05. P. guajava however, had the highest alkaloids content (1.90±0.02%) while A. sativum had the highest flavonoids content (4.20±0.02%). A. indica contained the highest phenols and tannins, (0.36±0.01%) and (2.63±0.01%) respectively. Saponins was found highest in A. sativum (2.60±0.02%).

Conclusion: The results justified the medicinal potentials of these plants in the treatment of diseases.