Structural Transformation of 8-5-Coupled Dehydrodiferulates by Human Intestinal Microbiota

Rachel R. Schendel, Cecile Karrer, Diana Bunzel, Melanie Huch, Andreas A. Hildebrand, Sabine E. Kulling, Mirko Bunzel

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

Ingested dehydrodiferulates (DFAs) are partially released from cereal dietary fiber by human colonic microbiota, but little research has explored the further microbial metabolism of 8-5-coupled DFAs. This study investigated the in vitro microbial metabolism and elucidated major metabolites of free 8-5-DFAs (benzofuran and open forms) and an esterified analogue, 8-5-DFA diethyl ester (benzofuran). Synthesized standard compounds were incubated with fresh human fecal suspensions. Metabolites were isolated and structurally elucidated using high-resolution-LC-time-of-flight-(ToF)-MS, GC-MS, and NMR. Nine metabolite structures were unambiguously characterized with NMR, and four additional metabolites were tentatively identified to reveal structural conversion motifs: propenyl side chain hydrogenation (all substrates), O-demethylation and reductive ring-opening (8-5-DFA diethyl ester and free 8-5-DFA [benzofuran]), and de-esterification (8-5-DFA diethyl ester). A pathway of microbial 8-5-DFA metabolism was proposed based on metabolite formation kinetics. Importantly, de-esterification of the 8-5-DFA diethyl ester occurred primarily after and/or concurrently with other metabolism steps. Cleavage to monomers was not observed.

Original languageEnglish
Pages (from-to)7975-7985
Number of pages11
JournalJournal of Agricultural and Food Chemistry
Volume63
Issue number36
DOIs
StatePublished - Aug 19 2015

Keywords

  • 8-5-dehydrodiferulic acid
  • diferulic acids
  • ferulic acid
  • human intestinal microbiota
  • microbial metabolism

ASJC Scopus subject areas

  • Chemistry (all)
  • Agricultural and Biological Sciences (all)

Fingerprint

Dive into the research topics of 'Structural Transformation of 8-5-Coupled Dehydrodiferulates by Human Intestinal Microbiota'. Together they form a unique fingerprint.

Cite this