Inhibitory mechanism of naringenin against carcinogenic acrylamide formation and nonenzymatic browning in Maillard model reactions.

Chemical model reactions were carried out to investigate the effect of a citrus flavonoid, naringenin, on the formation of acrylamide under mild heating conditions. Results showed that naringenin significantly and dose dependently inhibited the formation of acrylamide (20-50% relative to the control), although not in a linear manner. Moreover, the presence of naringenin in acrylamide-producing models effectively reduced the extent of browning. Careful comparison of the HPLC chromatograms of samples from the chemical model reactions revealed that naringenin likely reacted with Maillard intermediates, giving rise to new derivatives. Subsequent LC-MS analyses suggested that the proposed derivatives have a predicted molecular mass of 341 Da. Eventually, two derivatives were purified and characterized with LC-MS/MS and NMR spectroscopy as 8-C-(E-propenamide)naringenin and 6-C-(E-propenamide)naringenin, respectively. In other words, naringenin, a rather weak antioxidant, strongly inhibited acrylamide formation probably by directly reacting with acrylamide precursors, thus diverting them from the pathways that lead to acrylamide formation.