title: Isolation and structural features of an antiradical polysaccharide of Capsicum annuum that interacts with BSA.
abstract: Red peppers, Capsicum annuum, are used worldwide as spices, foods and medicines. Herein, we have analyzed an antiradical polysaccharide isolated from red peppers through successive acetate buffer extraction. This macromolecule was purified using graded precipitation with ethanol, α-amylase treatment, deproteination and anion-exchange chromatography. This highly-branched polysaccharide (360 kDa) was esterified with phenolic acids and contained a (1,3)-linked-β-Galp chain substituted at O-6 by (1,6)-linked-β-Galp residues. The latter was substituted at O-3 by (1,5)- and (1,3,5)-linked-α-Araf residues, and non-reducing end-units of α-Araf and β-Galp. The antiradical potential of this polysaccharide was comparable to standard antioxidants. The phenolic acid residues were the functional sites. This polysaccharide could form complex with bovine serum albumin having binding constant K = 5.24 × 10(6)/M and change its microenvironment. Thus, aqueous extraction method provides a macromolecule that stimulates biological responses; this emphasizes the significance of red pepper as dietary antioxidant.
authors.affiliation: Natural Products Laboratory, Department of Chemistry, The University of Burdwan, West Bengal 713 104, India.
authors.forename: Sujay Kumar
authors.initials: SK
authors.lastname: Majee
authors.affiliation: Natural Products Laboratory, Department of Chemistry, The University of Burdwan, West Bengal 713 104, India.
authors.forename: Sayani
authors.initials: S
authors.lastname: Ray
authors.affiliation: Natural Products Laboratory, Department of Chemistry, The University of Burdwan, West Bengal 713 104, India.
authors.forename: Kanika
authors.initials: K
authors.lastname: Ghosh
authors.affiliation: Montpellier SupAgro-INRA-UMII-CIRAD, UMR IATE, 2, Place Pierre Viala, 34060 Montpellier Cedex 01, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Micard
authors.affiliation: Natural Products Laboratory, Department of Chemistry, The University of Burdwan, West Bengal 713 104, India. Electronic address: bray@chem.buruniv.ac.in.
authors.forename: Bimalendu
authors.initials: B
authors.lastname: Ray
mesh_terms: D000107:Acetylation; D000818:Animals; D001089:Arabinose / Q000737:chemistry; D002212:Capsicum / Q000737:chemistry*; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D016166:Free Radical Scavengers / Q000494:pharmacology; D005609:Free Radicals / Q000737:chemistry*; D005690:Galactose / Q000737:chemistry; D006027:Glycosides / Q000737:chemistry; D062385:Hydroxybenzoates; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008970:Molecular Weight; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D012710:Serum Albumin, Bovine / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D055672:Static Electricity
chemical_list: D016166:Free Radical Scavengers; D005609:Free Radicals; D006027:Glycosides; D062385:Hydroxybenzoates; D011134:Polysaccharides; D012710:Serum Albumin, Bovine; D001089:Arabinose; C017616:phenolic acid; D005690:Galactose
keywords: Antioxidative activity; BSA–polysaccharide interaction; C. annuum; Polysaccharide