Acute and subchronic toxicity study of nonpolar extract of licorice roots in mice.

Licorice is used as a medicinal plant, and several studies have shown that licorice has beneficial effects. The objective of this study was to evaluate the safety of nonpolar licorice extract using toxicity experiments. Nonpolar extract from the root of Glycyrrhiza uralensis (NERG) was analyzed by high-performance liquid chromatography (HPLC). Antioxidant ability was determined by method of TPC and DPPH. Blood pressure was monitored by using blood pressure meter. In the acute study, a single dose (2,000 mg/kg) was orally administered to mice. In the subchronic study, mice were treated with extract at doses (50, 100, 500, and 1,000 mg/kg) for 120 days. Significantly difference was not shown at blood pressure, hematological, and biochemical parameters, and histopathology on mice. The results suggested that at acute and subchronic toxicity, each levels of nonpolar licorice extract administration in experiments did not cause toxicity effects or death on mice.