It is widely used in traditional Chinese medicine. In vitro cytotoxic activity of theL. strychnifolia essential oil on three human cancer cell lines (A549, HeLa, andHep G2) was examined using a modified MTT assay (Yan et al. 2009). The leafessential oil showed the strongest cytotoxicity on the cancer cell lines tested with50% inhibitory concentration (IC50) values ranging from 22 to 24 g/ml after 24 h oftreatment.