Assessment of phenolic contributors to antioxidant activity of new kiwifruit cultivars using cyclic voltammetry combined with HPLC. (1st December 2018)

• Record Type: Journal Article
• Authors: Jiao, Yang; Kilmartin, Paul A.; Fan, Mingtao; Quek, Siew Young
• Is Part Of: Food chemistry. Volume 268(2018)
• Page Start: 77
• Page End: 85
• Publication Date: 2018-12-01
• Subjects: Kiwifruit -- Phenolic compounds -- Antioxidants -- Antioxidant activity -- Cyclic voltammetry -- HPLC; Catechin (PubChem CID: 9064) -- Epicatechin (PubChem CID: 72276) -- Epicatechin gallate (PubChem CID: 107905) -- Epigallocatechin gallate (PubChem CID: 65064) -- Rutin (PubChem CID: 5280805) -- Quercetin (PubChem CID: 5280343) -- Gallic acid (PubChem CID: 370) -- Vanillic acid (PubChem CID: 8468) -- Protocatechuic acid (PubChem CID: 72) -- Syringic acid (PubChem CID: 10742) -- p-Coumaric acid (PubChem CID: 637542) -- Ferulic acid (PubChem CID: 445858) -- Caffeic acid (PubChem CID: 689043) -- trans-Cinnamic acid (PubChem CID: 444539); Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2018.06.046
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Two new kiwifruit cultivars were assessed for phenolic profile and reducing power. Cyclic voltammetry was efficient in evaluating phenolic class and reducing power. New cultivars have higher phenolic content and reducing powers than the 'Hayward'. Epicatechin was the predominant phenolic antioxidant in flesh and skins. The skins contained 3.44 fold more phenolics than flesh of the three cultivars. Abstract: The phenolics profile of two new kiwifruit cultivars, Zespri® SunGold and Zespri® Sweet Green, were characterized and quantified for the first time using cyclic voltammetry, an electrochemical method, combined with HPLC. Results from the cyclic voltammetry revealed high correlations with those obtained from the spectrophotometry and HPLC methods, providing evidence to support the application of cyclic voltammetry as a rapid method in determining the phenolic profile and reducing power of kiwifruit extracts. Catechol-containing phenolics were identified as the major phenolic sub-class in the skins while flavonoids and phenolic acids were abundant in flesh of the tested cultivars. Epicatechin was the predominant phenolic compound and contributor to antioxidant capacity in all samples. Results also showed that SunGold and Sweet Green (both flesh and skin) exhibited significantly higher phenolic contents and antioxidant activities comparing with the well-established commercial 'Hayward' cultivar, indicating their commercial value and potential applications in food and nutraceuticals.