Phenolic content and antioxidant activities of white and purple juices manufactured with organically- or conventionally-produced grapes.

Although the beneficial effects of moderate wine intake are well-known, data on antioxidant capacity of grape juices are scarce and controversial. The purpose of this study was to quantify total polyphenols, anthocyanins, resveratrol, catechin, epicatechin, procyanidins, and ascorbic acid contents in grape juices, and to assess their possible antioxidant activity. Eight Vitis labrusca juices--white or purple, from organically- or conventionally-grown grapes, and obtained in pilot or commercial scale--were used. Organic grape juices showed statistically different (p<0.05) higher values of total polyphenols and resveratrol as compared conventional grape juices. Purple juices presented higher total polyphenol content and in vitro antioxidant activity as compared to white juices, and this activity was positively correlated (r=0.680; p<0.01) with total polyphenol content. These results indicate that white and purple grape juices can be used as antioxidants and nutritional sources.

[1]  D M Goldberg,et al.  Resveratrol: a molecule whose time has come? And gone? , 1997, Clinical biochemistry.

[2]  D. Gómez-Coronado,et al.  Concentrated red grape juice exerts antioxidant, hypolipidemic, and antiinflammatory effects in both hemodialysis patients and healthy subjects. , 2006, The American journal of clinical nutrition.

[3]  Y. Park,et al.  Daily grape juice consumption reduces oxidative DNA damage and plasma free radical levels in healthy Koreans. , 2003, Mutation research.

[4]  J. V. Bannister,et al.  Assays for superoxide dismutase. , 2006, Methods of biochemical analysis.

[5]  A. Waterhouse,et al.  A Direct HPLC Separation of Wine Phenolics , 1994, American Journal of Enology and Viticulture.

[6]  E. Wills.  Mechanisms of lipid peroxide formation in animal tissues. , 1966, The Biochemical journal.

[7]  L. Ferguson.  Role of plant polyphenols in genomic stability. , 2001, Mutation research.

[8]  F. Lajolo,et al.  Ascorbic acid biosynthesis: a precursor study on plants , 2004 .

[9]  M. K. Kim,et al.  Effects of different grape formulations on antioxidative capacity, lipid peroxidation and oxidative DNA damage in aged rats. , 2006, Journal of nutritional science and vitaminology.

[10]  K. Singletary,et al.  Inhibition of rat mammary tumorigenesis by concord grape juice constituents. , 2003, Journal of agricultural and food chemistry.

[11]  D. Barrett,et al.  Comparison of the total phenolic and ascorbic acid content of freeze-dried and air-dried marionberry, strawberry, and corn grown using conventional, organic, and sustainable agricultural practices. , 2003, Journal of agricultural and food chemistry.

[12]  Anne S. Meyer,et al.  Commercial Grape Juices Inhibit the in Vitro Oxidation of Human Low-Density Lipoproteins , 1998 .

[13]  D. Peyron,et al.  Effect of Enological Practices on the Resveratrol Isomer Content of Wine , 1995 .

[14]  R. Lamuela-Raventós,et al.  Analysis of total phenols and other oxidation substrates and antioxidants by means of Folin-Ciocalteu reagent , 1999 .

[15]  D. Shanmuganayagam,et al.  Grape juice but not orange or grapefruit juice inhibits platelet activity in dogs and monkeys. , 1998, The Journal of nutrition.

[16]  F. F. Moraes,et al.  Methyl parathion activation by a partially purified rat brain fraction. , 1996, Toxicology letters.

[17]  A. Avcı,et al.  Comparison of antioxidant potentials of red wine, white wine, grape juice and alcohol. , 1999, Current medical research and opinion.

[18]  B. Zoecklein.  Wine Analysis and Production , 1995 .

[19]  J. Terao,et al.  HPLC method for evaluation of the free radical-scavenging activity of foods by using 1,1-diphenyl-2-picrylhydrazyl. , 1998, Bioscience, biotechnology, and biochemistry.

[20]  R. Wolfe,et al.  The synthesis of amino acids by Methanobacterium omelianskii. , 1966, The Biochemical journal.

[21]  H. Aebi,et al.  Catalase in vitro. , 1984, Methods in enzymology.

[22]  V. L. F. Cunha Bastos,et al.  Brain acetylcholinesterase as an in vitro detector of organophosphorus and carbamate insecticides in water , 1991 .

[23]  B. Ames,et al.  Oxidants, antioxidants, and the degenerative diseases of aging. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[24]  D. Stansbie,et al.  Effect of concentrated red grape juice consumption on serum antioxidant capacity and low-density lipoprotein oxidation. , 1997, Annals of nutrition & metabolism.

[25]  R. V. van Breemen,et al.  An LC-MS method for analyzing total resveratrol in grape juice, cranberry juice, and in wine. , 2002, Journal of agricultural and food chemistry.

[26]  R. Prior,et al.  Total Antioxidant Capacity of Fruits , 1996 .

[27]  Tibor Fuleki,et al.  Effects of cultivar and processing method on the contents of catechins and procyanidins in grape juice. , 2003, Journal of agricultural and food chemistry.

[28]  M. Lucarini,et al.  Nutrients and antioxidant molecules in yellow plums (Prunus domestica L.) from conventional and organic productions: a comparative study. , 2007, Journal of agricultural and food chemistry.

[29]  M. Carbonaro,et al.  Modulation of antioxidant compounds in organic vs conventional fruit (peach, Prunus persica L., and pear, Pyrus communis L.). , 2002, Journal of agricultural and food chemistry.

[30]  Alberto Dávalos,et al.  Antioxidant properties of commercial grape juices and vinegars , 2005 .