Retinylisoflavonoid as a novel membrane antioxidant

Cun Bin An, Ran Liang, Xiaohua Ma, Li Min Fu, Jian Ping Zhang*, Peng Wang, Rui Min Han, Xi Cheng Ai, Leif H. Skibsted

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

We report a novel molecular dyad as an antioxidant, retinylisoflavonoid, with a retinal analogue C22-aldehyde and the isoflavonoid daidzein covalently linked. Its physicochemical properties, pKa (pK a1 = 8.45, pKa2 = 11.42), oxidation potential (1.03 V vs NHE), and Log10 partition (Log P = 1.96), as well as the Trolox equivalent antioxidant capacity (TEAC = 0.4), have been characterized. Spectroscopic and quantum chemical investigations have revealed the following unique structural characters: (i) Either free in solution or included in liposomal membranes, the C22-aldehyde moiety of retinylisoflavonoid is coplanar with the B-ring of daidzein owing to the strong intramolecular hydrogen bonding C 14-=O···HO-B4′. Accordingly, the C 22-aldehyde moiety extends its π-conjugation significantly to the B-ring. (ii) The inherent amphiphilicity of retinylisoflavonoid allows the C22-aldehyde moiety embedded in the lipid phase of the liposomes, whereas the daidzein counterpart stays at the membrane surface, in effect facilitating interior-to-surface radical communication. As the result, the antilipooxidation activity of retinylisoflavonoid is improved significantly in protecting membrane lipids compared to the parent compounds alone or in combination, and importantly, the performance is more prominent under higher-level oxidative stress. This work provides an advanced case study of new antioxidant development based on optimized electronic and molecular structures.

Original languageEnglish (US)
Pages (from-to)13904-13910
Number of pages7
JournalJournal of Physical Chemistry B
Volume114
Issue number43
DOIs
StatePublished - Nov 4 2010

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films
  • Materials Chemistry

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