Evaluation of Toxicity effects of Ethanol Extract of Fruit Rind of Cucumis metuliferus on the Biochemical, Hematological and Histological Parameters of Albino Rats

Background: Fruit rinds/peels form major part of food waste, yet they possess nutrients and biologically-active constituents which have been found useful in nutrition and therapy. Nevertheless, the safety of their usage is a drawback and therefore requires a complete evaluation of their safety profile. This study evaluated the biochemical, hematological and histological toxic effects of the ethanol extract of the fruit rind of Cucumis metuliferus in albino rats.

Methods: The acute oral toxicity test (LD50) was done using Lorke’s method and then 16 male albino rats in four (4) groups (A, B, C and D) of four rats (4) with mean weight of 173.8 g were daily administered orally with 100, 200, 400 mg/kg body weight of the extract respectively with group D serving as the control. Treatment lasted for 14 days after which blood samples were collected for biochemical and hematological assays. Kidney, liver and heart were removed and fixed in 10% formalin solution for histological studies.

Results: The LD50 result showed no death and toxic sign up to 5000 mg/kg bodyweight. The result of biochemical assays in comparison between the treated and control groups showed no significant difference (p>0.05) in the levels of liver enzymes, albumin, total protein and the antioxidant enzyme activities. However, creatinine, direct and total bilirubin of group A indicated a significant difference (p<0.05) when compared with the other groups. Hematology as well as biochemical parameters of the kidney and lipid of the treated groups showed significant difference (p<0.05) in the electrolytes, cholesterol and high-density lipoprotein (HDL) levels while there was no significant difference (p>0.05) in the urea, triglyceride and low-density lipoprotein (LDL) levels when compared with the control. Some degenerative histological changes were found in the kidney, liver and heart tissues.

Conclusion: The ethanol extract of the fruit rind of Cucumis metuliferus caused some biochemical and histological alterations and may not be safe. Therefore, caution should be exercised when in use.