Alkylresorcinols

Alkylresorcinols are phenolic lipids present in the outer parts of rye and wheat kernels. In animal feed containing rye they are considered to be inhibitory components responsible for lowering feed intake and growth rate. Whether this occurs in human subjects is not known, but would perhaps not be a negative property in the overweight world. Interest in alkylresorcinols, however, continued and they were shown to have many biological activities, including antimicrobial, antiparasitic, antitumour and antioxidative effects. Relatively little is known about the metabolism. Human subjects absorb alkylresorcinols in the small intestine via the lymph system and they are circulating bound to the lipoproteins. Human urine after wheat-bran and rye bread diets were shown to contain two metabolites, 3,5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), but very small amounts of unchanged alkylresorcinols, supporting the hypothesis that alkylresorcinols are metabolised in humans via ß-oxidation of their alkyl-chains.

Because alkylresorcinols are present in high amounts in whole grain wheat and rye but not in appreciable amounts in other foods, it was proposed that alkylresorcinols and, more conveniently, their metabolites could serve as biomarkers of wholegrain intake. This has recently been shown in subjects living in U.S. and Finland consuming their habitual diets. The intake of alkylresorcinols in Scandinavian and the UK using food supply data showed that UK had the lowest (11.9 mg/day), Sweden (17.5 mg/day) and Norway (18.5 mg/day) had moderate, while Finland (39.8 mg/day) and Denmark (37.1 mg/day) had the highest intake of alkylresorcinols.