Leuconostoc mesenteroides glucansucrase synthesis of flavonoid glucosides by acceptor reactions in aqueous-organic solvents

Carbohydr Res. 2006 May 22;341(7):855-63. doi: 10.1016/j.carres.2006.02.008. Epub 2006 Mar 10.

Abstract

The enzymatic glucosylation of luteolin was attempted using two glucansucrases: the dextransucrase from Leuconostoc mesenteroides NRRL B-512F and the alternansucrase from L. mesenteroides NRRL B-23192. Reactions were carried out in aqueous-organic solvents to improve luteolin solubility. A molar conversion of 44% was achieved after 24h of reaction catalysed by dextransucrase from L. mesenteroides NRRL B-512F in a mixture of acetate buffer (70%)/bis(2-methoxyethyl) ether (30%). Two products were characterised by nuclear magnetic resonance (NMR) spectroscopy: luteolin-3'-O-alpha-d-glucopyranoside and luteolin-4'-O-alpha-d-glucopyranoside. In the presence of alternansucrase from L. mesenteroides NRRL B-23192, three additional products were obtained with a luteolin conversion of 8%. Both enzymes were also able to glucosylate quercetin and myricetin with conversion of 4% and 49%, respectively.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Buffers
  • Glucosides / chemistry*
  • Glycosyltransferases / biosynthesis*
  • Leuconostoc / enzymology*
  • Molecular Conformation
  • Nuclear Magnetic Resonance, Biomolecular
  • Solubility
  • Solvents / chemistry*
  • Substrate Specificity
  • Water / chemistry*

Substances

  • Buffers
  • Glucosides
  • Solvents
  • Water
  • Glycosyltransferases
  • alternansucrase