Unique Pattern of Protein-Bound Maillard Reaction Products in Manuka (Leptospermum scoparium) Honey

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

As a unique feature, honey from the New Zealand manuka tree (Leptospermum scoparium) Contains substantial amounts of dihydroxyacetone (DHA) and methylglyoxal (MGO). Although MGO is a reactive intermediate in the Mallard reaction, very little is known about reactions of MGO with honey proteins. We hypothesized that the abundanee of MGO should result in a particular pattern of protein-bound Maillard reaction products (MRPs) in manuka honey. A protein-rich high molecular-weight fraction was isolated from 12 manuka and 8 non-manuka honeys and hydrolyzed enzymatically. By HPLC-MS/ MS, 8 MRPs, namely, N-e-fructosyllysine, N-8-maltulosyllysine, carboxymethyllysine, carboxyethyllysine (CEL), pyrraline, formyline, maltosine, and methylglyoxal-derived hydroimidazolone 1 (MG-H1), were quantitated. Compared to non-manuka honeys, the manuka honeys were characterized by high concentrations of CEL and MG-H1, whereas the formation of N-sfructosyllysine was suppressed, indicating concurrence reactions of glucose and MGO at the 8-amino group of protein-bound lysine. Up to 31% of the lysine and 8% of the arginine residues, respectively, in the manuka honey protein can be modified to CEL and MG-H1, respectively. CEL and MG-Hi concentrations correlated strongly with the MGO concentration of the honeys. Manuka honey possesses a special pattern of protein-bound MRPs, which might be used to prove the reliability of labeled MGO levels in honeys and possibly enable the detection of fraudulent MGO or DHA addition to honey.

Details

Original languageEnglish
Pages (from-to)3532-3540
Number of pages9
JournalJournal of Agricultural and Food Chemistry
Volume65
Issue number17
Publication statusPublished - 3 May 2017
Peer-reviewedYes

External IDs

Scopus 85018981329
WOS 000400802600014
ORCID /0000-0001-8528-6893/work/142256483

Keywords

Keywords

  • Maillard reaction, glycation, manuka honey, methylglyoxal, methylglyoxal-derived hydroimidazolone I (MG-HI), N-epsilon-carboxyethyllysine (CEL), honey protein, NEW-ZEALAND HONEYS, PERFORMANCE LIQUID-CHROMATOGRAPHY, ADVANCED GLYCATION ENDPRODUCTS, AMINO-ACIDS, ANTIBACTERIAL ACTIVITY, AQUEOUS-SOLUTION, MODEL SYSTEMS, METHYLGLYOXAL, IDENTIFICATION, LYSINE