Polyphenolic Compounds Analysis of Old and New Apple Cultivars and Contribution of Polyphenolic Profile to the In Vitro Antioxidant Capacity

• Published in: Antioxidants 2018-01, Vol.7 (1), p.20
• Main Authors: Kschonsek, Josephine, Wolfram, Theresa, Stöckl, Annette, Böhm, Volker
• Format: Article
• Language: English
• Subjects: Antioxidants; apple polyphenols; Ascorbic acid; Cultivars; Flavonols; Folin-Ciocalteu; Glycosides; High-performance liquid chromatography; HPLC-DAD; ORAC; Phenolic acids; Polyphenols; Quercetin; relative antioxidant activity; TEAC; vitamin C; Vitamin E
• ISSN: 2076-3921; 2076-3921
• DOI: 10.3390/antiox7010020

Polyphenols are antioxidant ingredients in apples and are related to human health because of their free radical scavenging activities. The polyphenolic profiles of old and new apple cultivars ( = 15) were analysed using high-performance liquid chromatography (HPLC) with diode array detection (DAD). The in vitro antioxidant capacity was determined by total phenolic content (TPC) assay, hydrophilic trolox equivalent antioxidant capacity (H-TEAC) assay and hydrophilic oxygen radical absorbance (H-ORAC) assay. Twenty polyphenolic compounds were identified in all investigated apples by HPLC analysis. Quercetin glycosides (203 ± 108 mg/100 g) were the main polyphenols in the peel and phenolic acids (10 ± 5 mg/100 g) in the flesh. The calculated relative contribution of single compounds indicated flavonols (peel) and vitamin C (flesh) as the major contributors to the antioxidant capacity, in all cultivars investigated. The polyphenolic content (HPLC data) of the flesh differed significantly between old (29 ± 7 mg/100 g) and new (13 ± 4 mg/100 g) cultivars, and the antioxidant capacity of old apple cultivars was up to 30% stronger compared to new ones.