Metal Contents and Acute Toxicity of Combined Vernonia amygdalina Leaves and Garcinia kola Seeds-VAGK, a Herbal and Nutritional Formulation in Male Wistar Rats


  • Elizabeth Bosede Bolajoko University of Ibadan
  • Alfred Francis Attah University of Ilorin
  • Olubayo Michael Akinosun University of Ibadan
  • Augustine Onyeaghala University College Hospital
  • - Jones Olanrewaju Moody University of Ibadan
  • Aye Aye Khine Sefako Makgatho Health Sciences University


acute toxicity, heavy metals, Vernonia amygdalina, Garcinia kola


The toxicity of the aqueous extracts of Vernonia amygdalina (VA) leaves and Garcinia kola (GK) seed separately and in combined formulation were investigated in male Wistar rats. Limit acute toxicity investigation of VA and GK using a dose of 1600 mg/kg body weight (b.wt) was carried out on 10 rats. Also, a full LD50 was performed on the combined VAGK with 13 rats randomly classified into control (1 rat) and two test phases. Phase-I, with nine rats, comprised three groups of three rats each, which respectively received 10, 100, and 1000 mg/kg b.wt and Phase-II with three rats received 1600, 2900 and 5000 mg/kg b.wt respectively. All rats were further observed for 14 days. Histological examination was carried out on harvested rats’ kidney and liver while metal analysis was performed on the powdered plants. All rats survived the limit dose and full LD50 tests. Kidney and liver histological test revealed no notable pathological changes in the tested plants. The concentration of heavy metals (mg/kg) in the plants’ extracts revealed Cd (0.15-0.25), which was within FAO/WHO recommended permissible limits while Pb (11.35-22.45), Co (0.14-1.25), Cr (6.25-8.85) and Ni (9.35-13.85) were above the limits. In conclusion, the acute oral toxicity test revealed no mortality and the histology examination of kidney and liver demonstrated no remarkable pathological changes in the treated rats.

However, findings following metal analysis suggested the need for a batch-by-batch heavy metal analysis on our soil to ensure that the heavy metal contents are well below the international permissible levels.



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How to Cite

Bolajoko, E. B., Attah, A. F., Akinosun, O. M., Onyeaghala, A., Moody, .- Jones O., & Khine, A. A. (2019). Metal Contents and Acute Toxicity of Combined Vernonia amygdalina Leaves and Garcinia kola Seeds-VAGK, a Herbal and Nutritional Formulation in Male Wistar Rats. African Journal of Biomedical Research, 22(2), 187 - 194. Retrieved from



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