In Vitro Vitamin C Equivalent Antioxidant Capacity, Cytotoxicity and Anti-Cancer Activity of Methanolic Urtica dioica L. Leaf Extract as a Food Supplement.

Antioxidant capacity, cytotoxicity on two vital cell lines and the anti-cancer activity of methanolic Urtica dioica L. leaf extract (UDE) collected from Duzkoy, Giresun, Turkey were studied by determining safe concentration. The antioxidant capacity of the extract was expressed as vitamin C equivalency by spectrophotometric MTT assay. The cytotoxic concentration 50% was measured by the linearity between UDE concentrations (CC50) and the cell viability of non-cancer kidney cell lines (BHK-21, MDBK). The anti-cancer activity was conducted on human hepatocellular carcinoma cells (HepG2) by determining inhibition concentration (IC50) on cell proliferation. The vitamin C equivalence of UDE increased linearly by increasing the concentration. The cytotoxic and non-toxic concentrations of UDE were determined on BHK-21 and MDBK with 15.71 mg/ml and 5.14 mg/ml of CC50 respectively. The extract inhibited the proliferation of human hepatocellular carcinoma cells with a 2.46 mg/ml of IC50. In conclusion, the present study tried to explain in detail the dose-dependent activity of Urtica dioica L. leaf extract. The dose-response results showed that Urtica dioica L. leaf extract could have low cytotoxicity, but potential anti-cancer activity at safe concentrations. [ABSTRACT FROM AUTHOR]