Crude peroxidase from onion solid waste as a tool for organic synthesis. Part II: oxidative dimerization–cyclization of methyl p-coumarate, methyl caffeate and methyl ferulate

The ability of a crude onion peroxidase preparation to act as a biocatalyst for the oxidative dimerization–cyclization of methyl p-coumarate, methyl caffeate and methyl ferulate is presented. The products of the reaction have been fully characterized and were found to possess potent antioxidant activity in a ferric reducing antioxidant power (FRAP) assay.