Acute and subchronic toxicity of FCD, a soybean extract combined with l-carnitine, in Sprague–Dawley rats

Abstract

Soy products are primarily composed of proteins, phytochemicals such as isoflavones, soy lipids, and carbohydrates. Recently, soy isoflavones with l-carnitine were reported to exhibit anti-obesity effects in mice. FCD, a combination of soybean extract and l-carnitine, is a newly developed food substance. As a part of its safety assessment, acute and 13-week subchronic toxicity studies were performed in a total of 100 Sprague–Dawley (SD) rats. In the acute study, a single limit dose of 2000mg/kg was orally administered to five male and five female rats. No adverse effects or mortality was observed during a 14-day period or upon gross pathological examination. In the subchronic study, FCD was orally administered in daily doses of 500, 1000, and 2000mg/kg for 13weeks, resulting in no mortality, and no changes in hematological and serum biochemistry parameters, gross pathology or histopathology. However, body weights of females were significantly decreased 10weeks after treatment at an average of 2000mg/kg. In addition, a slight decrease in mean food and water consumption was observed at the same dose level for 13weeks. Therefore, the no-observed-adverse-effect-level (NOAEL) of FCD was considered to be 2000mg/kg for male and 1000mg/kg for female SD rats.