The antioxidant activity of ethanol extracts of Atrichum undulatum, Polytrichum formosum, Pleurozium schreberi and Thuidium tamariscinum was evaluated by an electrochemical method (cyclic voltammetry) and standard photometric methods: Fe(III) to Fe(II) reducing power, nitric oxid scavenging (NO) assay and simulation of Fenton-type reaction by nonsite-specific and site-specific hydroxyl radical-mediated 2-deoxy-D-ribose degradation inhibition