The aim of this study was to determine the phosphorus, magnesium, sodium, potassium, and calcium contents, as well as the total phenolic content and antioxidant activity in white, yellow, and red onion varieties. | Turkish Journal of Agriculture and Forestry Turk J Agric For (2015) 39: 999-1004 © TÜBİTAK doi: Research Article The antioxidant capacity and macroelement content of several onion cultivars 1, 2 1 3 Jiří MLČEK *, Magdaléna VALŠÍKOVÁ , Helena DRUŽBÍKOVÁ , Pavel RYANT , 4 5 6 Tunde JURÍKOVÁ , Jiří SOCHOR , Marie BORKOVCOVÁ 1 Department of Food Chemistry and Analysis, Faculty of Technology, Tomas Bata University, Zlin, Czech Republic 2 Department of Vegetable Production, Faculty of Horticulture and Landscape Engineering, Slovak University of Agriculture, Nitra, Slovakia 3 Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of Agronomy, Mendel University, Brno, Czech Republic 4 Department of Natural and Informatics Sciences, Faculty of Central European Studies, Constantine the Philosopher University, Nitra, Slovakia 5 Department of Viticulture and Enology, Faculty of Horticulture, Mendel University, Brno, Czech Republic 6 Department of Zoology, Fisheries, Hydrobiology and Apidology, Faculty of Agronomy, Mendel University, Brno, Czech Republic Received: Accepted/Published Online: Printed: Abstract: The aim of this study was to determine the phosphorus, magnesium, sodium, potassium, and calcium contents, as well as the total phenolic content and antioxidant activity in white, yellow, and red onion varieties. It is evident from the results that the highest content of all of these macroelements except phosphorus was found in the cultivar Fireball. In this cultivar, the phosphorus content was the lowest of all cultivars. The total phenolic content ranged from to g of gallic acid equivalents kg–1 and the antioxidant capacity ranged from and g of ascorbic acid equivalents kg–1 of fresh weight and was slightly higher in red onion cultivars than in white and yellow cultivars. The significant influence of color was .
