The antioxidant capacity of phenolic acids, caffeine or melanoidins could be associated with the inhibition ofmutagens, through scavenging activity against free radicals (Azam et al., 2003; Farombi & Fakoya, 2005; Rufián-Henares & Morales, 2007). The high level of antioxidant activity of the tested spent coffee extracts (Bravo et al., 2012) and their capability to reduce ROS level and DNA strand breaks induced by H2O2 in a human cell line (Bravo et al., 2013a) may support the radical scavenging theory