Assessment of the Safety of Aqueous Extract of Maize (Zea mays) Husks in Wistar Albino Rats

Aims: The possible toxic impact of aqueous extract of maize husks (HA) on Wistar albino rats was investigated. Study Design: Experimental design. Place and Duration of Study: This study was conducted at the Federal University of Technology, Akure, Nigeria between January 2020 and April 2020. Methodology: The extract was prepared adopting the cold extraction procedure. Forty-eight (48) Wistar albino rats were used for this study. Acute toxicity study was carried out by administering HA at a single dose of 2000, 4000 and 8000 mg/kg body weight to the rats by oral gavage. The rats were observed for 14 days for any mortality or signs of toxicity. For sub-acute study, doses of 200, 400 and 800 mg/kg body weight were orally administered daily for 28 days. Biochemical and haematological parameters as well as histopathological studies were carried out after the experiments. Results: Acute toxicity results indicated that the median lethal dose (LD50) of HA was greater than 8000 mg/kg. There was remarkable body weight gain (P ≤ 0.05) in both male and female rats in all the sub-acute groups and acute group treated with 8000mg/kg. In the acute and sub-acute toxicity study, slight difference was recorded between the biochemical and haematological parameters of the treated rats dosed with the extract and the control. There was a significant increase in Packed Cell Volume (PCV) of female rats and lymphocytes of male rats treated with 800 mg/mL and 400 mg/mL respectively. The total protein, glucose and urea level of male rats treated with 200 mg/mL reduced while urea level of females treated with 200 mg/mL and 400 mg/mL also reduced remarkably. However, histological data showed no significant difference. Conclusion: In general, the extract was found to show no toxic effect on the rats and hence it is safe for potential therapeutic use.