Substituted galacturonan from starfruit: Chemical structure and antinociceptive and anti-inflammatory effects

Int J Biol Macromol. 2016 Mar;84:295-300. doi: 10.1016/j.ijbiomac.2015.12.034. Epub 2015 Dec 17.


Starfruit (Averrhoa carambola L.) is an edible tropical fruit, which is usually consumed as a fresh table fruit or as fruit juice. It also exhibits various pharmacological activities. In this study, polysaccharides were extracted with boiling water and purified by freeze-thawing and Fehling treatments. After purification steps, a homogenous fraction was obtained. It was analyzed by sugar composition, gel permeation chromatography, methylation, and two-dimensional nuclear magnetic resonance (2D NMR) spectroscopy analyses. It comprised arabinose (Ara), galactose (Gal), and galacturonic acid (GalA) in a molar ratio of 12.3:1.7:86.0. Methylation and NMR spectroscopy analyses showed that it contained a substituted galacturonan composed of (1→4)-linked α-D-Galp A units branched at O-2 by (1→5)-linked α-L-Araf and terminal α-L-Araf and α-D-Galp A units. The effect of PFSCW (10-300mg/kg, i.p.) on nocifensive behavior induced by intraplantar injection of formalin in mice was evaluated. The fraction demonstrated antinociceptive and anti-inflammatory properties, suggesting that it may be useful in therapeutic intervention for the management of inflammatory pain.

Keywords: Anti-inflammatory and antinociceptive activities; Starfruit; Substituted galacturonans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analgesics / chemistry*
  • Analgesics / pharmacology
  • Animals
  • Anti-Inflammatory Agents / chemistry*
  • Anti-Inflammatory Agents / pharmacology
  • Averrhoa / chemistry*
  • Disease Models, Animal
  • Female
  • Magnetic Resonance Spectroscopy
  • Mice
  • Molecular Structure
  • Pectins / chemistry*
  • Pectins / pharmacology
  • Plant Extracts / chemistry*
  • Plant Extracts / pharmacology
  • Polysaccharides / chemistry


  • Analgesics
  • Anti-Inflammatory Agents
  • Plant Extracts
  • Polysaccharides
  • Pectins
  • polygalacturonic acid