Acute and Subacute Toxicity Assessment of Crude Aqueous Extract of Melastoma malabathricum Leaves

Melastoma malabathricum (MM), also known as “Senduduk,” is a medicinal herb commonly used among the indigenous folks in Malaysia as traditional medicine for practical purposes. Many toxicity profile studies have been carried out on MM extract. However, very few studies have described the toxicity profile of MM aqueous extract. Therefore, this study aimed to investigate the acute and subacute oral toxicity of MM crude aqueous extract using Sprague Dawley rats. A total of 34 female Sprague Dawley rats were randomly divided into six groups for acute (n=5) and subacute (n=6) studies. The duration for the acute and subacute studies was 14 days and 28 days. A single dose of MM extract was fixed at 3000 mg/kg and did not show any signs of toxicity or mortality during 14 days of observation. In the 28 days repeated dose toxicity test, the rats were orally fed with three different doses, 100 mg/kg, 500 mg/kg, and 1000 mg/kg of body weight/day, revealed no major significant change (p<0.05) in their physical appearance, behaviour, haematology, serum biochemistry indicators, and relative organ weight when compared to the control group. The findings were supported by a microscopic histopathology examination of the liver after feeding with MM crude aqueous extract. This study suggests that oral application of 3000 mg/kg in acute toxicity assay and 100 mg/kg, 500 mg/kg, and 1000 mg/kg of MM crude aqueous extract in subacute toxicity assay do not induce adverse effects in rats.