Safety evaluation of mulberry leaf extract: Acute, subacute toxicity and genotoxicity studies

Mulberry (Morus alba L.) leaves are of broad popular use for food or remedy purposes due to their bioactive properties, especially antidiabetic activity and antioxidative activity. The present study aimed to assess the toxicological profile of mulberry leaf extract (MLE), through acute, subacute toxicity and genotoxicity tests. Male and female rats received by gavage 15.0 g/kg bw of MLE in the acute toxicity test, and 0, 1.88, 3.75 and 7.50 g/kg bw/d of MLE for subacute toxicity test. In the acute toxicity study, no mortality or behavioral changes were observed, indicating the LD₅₀ is higher than 15.0 g/kg bw. In the subacute toxicity test, no significant changes were observed in hematological, biochemical or histopathological parameters in the animals exposed. The no-observed-adverse-effect level in the subacute toxicity study was considered to be 7.50 g/kg bw/d, the highest dose tested. In the genotoxicity study, MLE showed no mutagenic activity in the Ames assay and no evidence of potential to induce chromosome aberrations or sperm abnormalities in mice exposed to 10 g/kg bw. Collectively, aqueous extract of mulberry leaves could be considered safe, and the results support the application of MLE as novel food ingredient or product.