Antigenotoxic and antioxidant activities of a polyphenolic extract from European Dracocephalum moldavica L.

The aim of the present study was to investigate the antigenotoxic and antioxidant activities of the crude hydromethanolic extract from the aerial parts of European Dracocephalum moldavica L. (Moldavian dragonhead). The total phenolic content estimated by the Folin-Ciocalteu assay was 289.55 +/- 2.63 mg of GAE/g of dry extract, and rosmarinic acid was the major polyphenol of Dracocephalum moldavica extract (107.11 +/- 0.83 mg/g of dry extract). In vitro antioxidant assays revelead remarkable scavenging effects against DPPH (EC50 = 23.10 +/- 0.10 mu g/mL), ABTS (EC50 = 8.0 +/- 0.10 mu g/mL) and superoxide anion radicals (EC50= 445.5 +/- 2.3 mu g/mL). The extract showed a high ferrous ion chelating activity (EC50 = 35.70 +/- 0.40 mu g/mL), a considerable reducing capacity, and good hydroxyl radical scavenging properties. Dracocephalum moldavica extract reduced, in a concentration-dependent manner, DNA damage induced by bleomycin in normal human dermal fibroblasts as measured by comet assay and micronucleus test. Exposure of dermal fibroblasts to Dracocephalum moldavica extract (100 mu g/mL) after preincubation with bleomycin (10 mu g/mL) resulted in the most significant antigenotoxic activity. The protective effects may be due to the free radical scavenging activity, iron-chelating properties and the possible intervention on DNA repair processes. (C) 2015 Elsevier B.V. All rights reserved.