title: Antioxidant activity of South African red and white cultivar wines: free radical scavenging.
abstract: The free radical scavenging activity of South African red (n = 46) and white (n = 40) cultivar wines was determined using 2,2'-azinobis(3-ethylbenzothialozinesulfonic acid) radical cations (ABTS(.+)) and 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH.). The total antioxidant activities (TAA) of red and white wines using ABTS(.+) were 14.916 and 0.939 mM Trolox, respectively, at corresponding total phenol (TP) contents of 2339.0 and 273.8 mg of gallic acid equiv/L. Ruby Cabernet wines had the lowest TAA(ABTS) (13.177 mM Trolox) of the red wines, whereas the TAA(ABTS) values of Chardonnay and Chenin blanc wines were the highest (1.060 mM Trolox) and lowest (0.800 mM Trolox) of the white wines. The TAA(DPPH) values were of the same magnitude as the TAA(ABTS) values, and similar trends were observed. TAA correlated (P < 0.001) with total phenol content of red (r = 0.935) and white (r = 0.907) wines, as well as flavanol content of red wines (r = 0.866) and tartaric acid ester content of white wines (r = 0.767). Canonical discriminant analysis using phenolic composition and antioxidant activity was applied to differentiate between red and white cultivar wines.
authors.affiliation: Department of Food Science, University of Stellenbosch, Private Bag X1, 7602 Matieland (Stellenbosch), South Africa.
authors.forename: Dalene
authors.initials: D
authors.lastname: De Beer
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Joubert
authors.forename: Wentzel C A
authors.initials: WC
authors.lastname: Gelderblom
authors.forename: Marena
authors.initials: M
authors.lastname: Manley
mesh_terms: D000872:Anthocyanins / Q000032:analysis; D000975:Antioxidants / Q000032:analysis*; D001205:Ascorbic Acid / Q000032:analysis / Q000737:chemistry; D052160:Benzothiazoles; D001713:Biphenyl Compounds; D016002:Discriminant Analysis; D016166:Free Radical Scavengers / Q000032:analysis* / Q000737:chemistry; D005638:Fruit / Q000737:chemistry*; D010636:Phenols / Q000032:analysis; D010851:Picrates / Q000737:chemistry; D013019:South Africa; D013451:Sulfonic Acids / Q000737:chemistry; D027843:Vitis / Q000737:chemistry*; D014920:Wine / Q000032:analysis*
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; D052160:Benzothiazoles; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010636:Phenols; D010851:Picrates; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; C004931:1,1-diphenyl-2-picrylhydrazyl; D001205:Ascorbic Acid