title: Frost Grape Polysaccharide (FGP), an Emulsion-Forming Arabinogalactan Gum from the Stems of Native North American Grape Species Vitis riparia Michx.
abstract: A new arabinogalactan is described that is produced in large quantity from the cut stems of the North American grape species Vitis riparia (Frost grape). The sugar composition consists of l-arabinofuranose (l-Araf, 55.2%) and d-galactopyranose (d-Galp 30.1%), with smaller components of d-xylose (11.2%), d-mannose (3.5%), and glucuronic acid (GlcA, ∼2%), the latter linked via a galactosyl residue. Permethylation identified 3-linked Galp residues, some substituted at the 2-position with Galp or Manp, terminal Araf and Xylp, and an internal 3-substituted Araf. NMR (HSQC, TOCSY, HMBC, DOSY) identified βGalp and three αAraf spin systems, in an Araf-α1,3-Araf-α1,2-Araf-α1,2-Galp structural motif. Diffusion-ordered NMR showed that the FGP has a molecular weight of 1-10 MDa. Unlike gum arabic, the FGP does not contain a hydroxyproline-rich protein (HPRP). FGP forms stable gels at >15% w/v and at 1-12% solutions are viscous and are excellent emulsifiers of flavoring oils (grapefruit, clove, and lemongrass), giving stable emulsions for ≥72 h. Lower concentrations (0.1% w/v) were less viscous, yet still gave stable grapefruit oil/water emulsions. Hence, FGP is a β1,3-linked arabinogalactan with potential as a gum arabic replacement in the food and beverage industries.
authors.affiliation: †Renewable Product Technology and ‡Functional Foods Research Units, U.S. Department of Agriculture, National Center for Agricultural Utilization Research, 1815 North University Street, Peoria, Illinois 61604, United States.
authors.forename: Neil P J
authors.initials: NP
authors.lastname: Price
authors.affiliation: †Renewable Product Technology and ‡Functional Foods Research Units, U.S. Department of Agriculture, National Center for Agricultural Utilization Research, 1815 North University Street, Peoria, Illinois 61604, United States.
authors.forename: Karl E
authors.initials: KE
authors.lastname: Vermillion
authors.affiliation: †Renewable Product Technology and ‡Functional Foods Research Units, U.S. Department of Agriculture, National Center for Agricultural Utilization Research, 1815 North University Street, Peoria, Illinois 61604, United States.
authors.forename: Fred J
authors.initials: FJ
authors.lastname: Eller
authors.affiliation: †Renewable Product Technology and ‡Functional Foods Research Units, U.S. Department of Agriculture, National Center for Agricultural Utilization Research, 1815 North University Street, Peoria, Illinois 61604, United States.
authors.forename: Steven F
authors.initials: SF
authors.lastname: Vaughn
mesh_terms: D002240:Carbohydrate Sequence; D004655:Emulsions / Q000737:chemistry; D005685:Galactans / Q000737:chemistry*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D053149:Plant Gums / Q000737:chemistry*; D018547:Plant Stems / Q000737:chemistry; D027843:Vitis / Q000737:chemistry*
chemical_list: D004655:Emulsions; D005685:Galactans; D053149:Plant Gums; C005653:arabinogalactan
keywords: Vitis riparia; arabinogalactan; beverage emulsifier; frost grape polysaccharide; gum arabic