Acute and sub-chronic toxicity studies of methanolic extract of Tulbaghia violacea rhizomes in Wistar rats

Abstract

The methanolic extract of the rhizome of Tulbaghia violacea (RTV) was tested for toxicity in albino Wistar rats. A single oral administration of a 5 g/kg dosage of RTV extract did not produce mortality or significant behavioral changes during 14 days of observation. In the sub-chronic study, the extract administered daily for a period of 28 days showed no mortality or morbidity and the relative weights of organs were not affected by the treatment. However, significant weight gain in both treated and control group was observed. Indicators of liver damage such as alanine amino transferase (ALT) and aspartate amino transferase (AST), as well as total serum protein and albumin showed no significant alteration in the extract treated animals when compared with the controls at all doses used. The extracts caused a significant (p<0.05) decrease in the activity of gamma glutamy transferase (ƔGT) and alkaline phosphatase (ALP) when compared with the control. However, the extract did not have any significant effect on markers of kidney function or hematological parameters in the rats, except in the female rats where a significant increase (p<0.05) in lymphocytes counts at 500 mg/kg was observed. Histopathological examination of the liver revealed no detectable inflammation. These results suggest that the rhizomes of T. violacea may be potentially safe for consumption.

Keywords: Tulbaghia violacea, rhizomes, acute toxicity, subchronic toxicity