Highland barley, a staple food in northwest China, is a well-known source of bioactive phytochemicals, including phenolic compounds. This study evaluated the inhibitory effects of highland barley bran extract (HBBE) on the advanced glycation end product (AGE) levels in a biscuit model, as measured by Nε-carboxymethyllysine (CML) content. CML was detected in all inhibition models using HBBE extracted with different solvents. Under optimal conditions, CML formation in the heated model system composed of glucose/lysine/linoleic acid was effectively inhibited by HBBE. This inhibition effect using extracts from 60% acetone solution was 45.58%. Five major phenolic acids from HBBE (ferulic, syringic, sinapic, p-coumaric, and caffeic acids) were further tested for their trapping and scavenging abilities of glyoxal, a reactive carbonyl species and a key intermediate compound for forming CML. This study has demonstrated that HBBE can potentially control CML formation during food processing, therefore effectively reducing glycation in foods and benefiting those with chronic diseases.
Keywords: Nε-carboxymethyllysine; biscuit; highland barley bran; inhibition; phenolic compounds.