International Journal of Modern Science and Technology

​​​​​​​September-October 2020, Vol. 5, No. 9-10, pp. 240-245. 

​​Effects of solvents on phytochemicals and antimicrobial activity of leaf extract from Vigna unguiculata

F. D. Davuram*¹, A. A. Alafy¹, D. Kubmarawa¹, S. I. Aliyu²
¹Department of Chemistry, Moddibo Adama University of Technology Yola, Nigeria.

²Microbiology Laboratory, Gombe State University, Nigeria.

​​*Corresponding author’s   


Cowpea (Vigna unguiculata (L.) Walp), an indigenous African legume crop, is used to treat epilepsy, bilharzia, chest pains and constipation. The leaf extract of V. unguiculata is an important source of polyphenolics and other phytochemicals with different functional effects like antimicrobial and antioxidant properties. This study strongly lay emphases on the effects of solvents on phytochemical and microbial properties of leaf extracts of V. unguiculata. The solvents like Ethanol, Ethyl ether, n- hexane and aqueous were used for the crude extracts for determination of the phytochemicals and microbial potentials of the leaf of V. unguiculata extract. The results of phytochemical screening of V. unguiculata leaf extract has shown the potency of the plant for antimicrobial activity. The antimicrobial activity of the different solvents shows greater activity against different bacterial strains which was performed by agar well diffusion method. Ethanol extract of Vigna leaf shows greater activity against bacterial strains compared to the other three solvents, n-Hexane extract shows least activity but shows greatest activity against E. coli as compared to ethanol, Ethyl acetate and aqueous extracts. Ethanol extracts of Vigna leaf shows greater activity against H. pyroli almost the same strength with standard drug (Amoxicilin 200 µg). From the results obtained it shows Ethanol extracts of V. unguiculata leaf extract gives better potency against bacterial activity.

Keywords:V. unguiculata; Phytochemical; Antimicrobial activity; Microorganisms; Extracts.


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