CHANGES IN THE ANTIOXIDANT CAPACITY OF POTATOES DEPENDING ON THE CULTIVAR, CONTENTS OF POLYPHENOLS, CHLOROGENIC ACID AND ASCORBIC ACID

Abstract

Effect of cultivar is known as the most important factor determining the qualitative and quantitative characteristics of potatoes. In the study the influence of this factor on the content of chlorogenic acid (CGA), ascorbic acid (AA), total polyphenols (TPC) and antioxidant capacity (TAC) in six potato cultivars (Viola, Malvina, Evelin, Arlet, Megan, Timea) was investigated. Potatoes were grown in vitro on peat substrate in a greenhouse and were harvested in the stage of physiological ripeness. The content of CGA, AA and the TAC were determined in fresh matter of potato tubers. CGA content was determined using standard HPLC gradient method. The lowest CGA amount was determined in cv. Viola (18.49 mg/kg FM) and the highest one in cv. Megan (46.73 mg/kg FM). The determined AA content was in interval 5.40 mg/100 g FM (cv. Evelin) – 20.10 mg/100 g FM (cv. Viola). Total antioxidant capacity expressed as mg eqv. Trolox/kg FM was the lowest in cv. Megan (41.06 mg TE/kg FM) and the highest in cv. Arlet (56.16 mg TE/kg FM). For TP content determination lyophilised potato samples were used. The determined values ranged from 256.44 until 425.37 mg.kg-1 DM in followed order: Evelin < Arlet < Megan < Timea < Viola < Malvina. The obtained results were evaluated using one-factorial analysis ANOVA (LSD-test), statistical software Statgraphic. Mutual correlations between the contents of CGA, AA, TP and TAC were evaluated using regression and correlation analysis (Microsoft Excel). Statistically significant dependence (P-value < 0.05) between observed factors was confirmed.