Evaluation and comparison of antioxidant activity and biochemical compounds in some coloured potato cultivars

Abstract

Potato is an important source of food, and in recent years, new genotypes have emerged on the European market, which particularly differentiate by the colour of tubers. The current study investigated and compared phytochemical properties and antioxidant activity of six potato cultivars: two of those with yellow-fleshed (Carpatin, Brasovean) and four with red and purple-fleshed (Cranberry Red, Mountain Rose, Purple Majesty, and Blue Congo), which were cultivated under the same climatic and soil conditions. The antioxidant activities were evaluated using two antioxidant systems 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The results show that yellow-fleshed cultivars had higher total soluble substance content; red and purple-fleshed cultivars had a higher content of antioxidant compounds. Cv. Blue Congo it was recorded the highest antioxidant capacity in terms of DPPH and ABTS, of 164.17 μmol ascorbic acid (AsA)/100 g FW (fresh weight) and 114.96 μmol AsA/100 g FW, respectively. The highest total phenolic content was registered at cv. Purple Majesty of 63.54 mg gallic acid equivalents/100 g FW. Regarding flavonoids, the highest content was 40.96 mg quercetin equivalents/100 g FW for cv. Blue Congo and anthocyanin at cv. Purple Majesty of 113.19 mg/100 g FW.