Carbonyl-trapping abilities of 5-alkylresorcinols

Abstract

In an attempt to investigate the carbonyl-trapping abilities of 5-alkylresorcinols, this study describes the role of these compounds in inhibiting the formation of the 2,5-dialkylpyridines (5-ethyl-2-methylpyridine, 5-butyl-2-propylpyridine, and 5-hexyl-2-pentylpyridine) produced by 2-alkenals (crotonaldehyde, 2-hexenal, and 2-octenal) in the presence of ammonia. 5-Alkylresorcinols (as well as orcinol and olivetol) inhibited the formation of pyridines to an extend that depended on the 2-alkenal involved and the reaction conditions. This inhibition was consequence of the trapping of 2-alkenals by the phenolics. Thus, the major adducts produced between the C21:0 alkylresorcinol and crotonaldehyde were isolated and characterized by nuclear magnetic resonance (NMR) and mass spectrometry (MS). These results confirm that, in addition to their free radical scavenging abilities, 5-alkylresorcinols also trap reactive carbonyls. Because trapped carbonyls are involved in the formation of flavors and processing-induced antioxidants, 5-alkylresorcinols might be implied in some of the observed differences between whole and refined grain products.

Keywords: 2-hexenal (PubChem ID: 5281168); 2-octenal (PubChem ID: 5283324); 5-Alkylresorcinols (PubChem ID: 85096661); Carbonyl-phenol reactions; Food carbonylome; Lipid oxidation; Maillard reaction; Michael reaction; Reactive carbonyls; crotonaldehyde (2-butenal) (PubChem ID: 447466); olivetol (PubChem ID: 10377); orcinol (PubChem ID: 10436)..