Evaluation of peroxynitrite-scavenging capacities of several commonly used fresh spices

Peroxynitrite-induced nitration of protein tyrosine residues is considered as one of the major pathological causes of several human diseases, e.g. cardiovascular disorders. Therefore, it appears that attenuation of peroxynitrite-induced nitration by certain foods could be beneficial to human health. Certain spices, used widely in folk medicine for cardiovascular disorders, conceivably protect against the activities of peroxynitrite. Seven culinary spices, including chilli, garlic, ginger, leek, onion, shallot and Welsh onion, were selected for this study. The peroxynitrite-scavenging capacities of these aqueous spice extracts were evaluated on the basis of their ability to attenuate peroxynitrite-induced nitrotyrosine formation in albumin. All of the spices had abilities to attenuate the peroxynitrite-mediated protein nitration. Ginger had outstanding peroxynitrite-scavenging ability. The phenolics and flavonoids in certain spices had abilities to suppress the peroxynitrite-mediated tyrosine nitration reaction. This indicates that these compounds could act as peroxynitrite-scavengers.