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Updated: Jul 30, 2026
11:49
Sequencing of Plant Wall Heteroxylans Using Enzymic, Chemical (Methylation) and Physical (Mass Spectrometry, Nuclear Magnetic Resonance) Techniques
Published on: March 24, 2016
Structural characterization of red wine rhamnogalacturonan II
1Institut National de la Recherche Agronomique, Laboratoire des Polymères et des Techniques Physico-Chimiques, Montpellier, France.
Carbohydrate Research
|September 2, 1996
Summary
Red wine contains rhamnogalacturonan II (RG-II), a complex pectic polysaccharide. Studies reveal its structure is conserved with plant cell walls, with some variations in dimerization and esterification.
Area of Science:
- Biochemistry
- Plant Cell Wall Biology
- Food Chemistry
Background:
- Rhamnogalacturonan II (RG-II) is a significant pectic polysaccharide found in plant cell walls and red wine.
- Understanding RG-II structure is crucial for comprehending cell wall architecture and wine quality.
Purpose of the Study:
- To isolate and characterize RG-II from red wine polysaccharides.
- To compare the structural features of wine RG-II with those from primary cell walls.
Main Methods:
- Anion-exchange chromatography for initial isolation.
- Concanavalin A affinity and size-exclusion chromatography for purification.
- Gas-phase electron ionization mass spectrometry (GC-EIMS) for linkage analysis.
Main Results:
- Four RG-II fractions were isolated, all containing diagnostic monosaccharides like apiose and aceric acid.
- Two RG-II fractions formed dimers via borate di-ester cross-links, suggesting a role in structural integrity.
- Structural variations were observed in backbone length, methyl-esterification, and borate di-ester presence.
Conclusions:
- Wine RG-II shares conserved major structural features with primary cell wall RG-II.
- Borate di-esters play a role in RG-II dimerization in wine.
- Structural heterogeneity exists within wine RG-II populations.
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