Determination of Anthocyanin Content and Antioxidant Capacity of Different Grape Varieties

Determinação da composição antociânica e da actividade antioxidante da uva de diferentes variedades de videira

Department of Bioresources and Food Science, College of Life and Environmental Sciences, Konkuk University, Seoul, South Korea.

^* corresponding author: Tel: +82024503739, fax: +820234365439, e-mail: nileshivraj@gmail.com and nileshivraj@rediffmail.com

Received: 27 August 2015
Accepted: 5 November 2015

Abstract

The aim of this study was to determine anthocyanin content and antioxidant activity of 20 different grape varieties, using HPLC and DPPH, FRAP and ABTS assays, respectively. The identified anthocyanins were malvidin-3-glucoside, delphinidin-3-glucoside, petunidin-3-glucoside, cyanidin-3 glucoside, and peonidin-3-glucoside on the basis of their retention times. Comparatively the total anthocyanin content varied from 181.2 mg/100 g FW (‘Vidal Black’) to 716.4 mg/ 100 g FW (‘Catawba’). High anthocyanin content was found in ‘Catawba’ (716.4 mg/100 g), ‘Ruby Seedless’ (634.5 mg/100 g) and ‘Campbell Early’ (611.1 mg/100 g) extracts. The antioxidant activities of grape extracts varied from 32.8% (‘Campbell Early’) to 87.6% (‘Hongiseul’) by DPPH, 79.1% (‘Campbell Early’) to 197% (‘Hongiseul’) in case of FRAP and 11.1% (‘Chasselas Rouge’) to 74.5% (‘Flouxa’) by ABTS antioxidant assay. The results suggested that the anthocyanin content in studied grape varieties showed statistically significant correlation with free radical scavenging activity. Thus depending on results we say that these grape varieties may serve as a potential source of nutraceuticals and functional food development.

Resumo

O objectivo do presente estudo foi determinar a composição antociânica e a actividade antioxidante da uva de 20 variedades de videira, por HPLC e através dos métodos DPPH, FRAP e ABTS, respectivamente. As antocianinas identificadas foram a malvidina-3-glucósido, delfinidina-3-glucósido, petunidina-3-glucósido, cianidina-3-glucósido e peonidina-3-glucósido, de acordo com os seus tempos de retenção. O teor total de antocianinas variou entre 181,2 mg/ 100 g FW (‘Vidal Black’) e 716,4 mg/ 100 g FW (‘Catawba’). Os teores mais elevados foram detectados nos extractos de uvas das variedades ‘Catawba’ (716,4 mg/100 g), ‘Ruby Seedless’ (634,5 mg/100 g) e ‘Campbell Early’ (611,1 mg/100 g). A actividade antioxidante dos extractos de uvas variou entre 32,8% (‘Campbell Early’) e 87,6% (‘Hongiseul’) pelo método DPPH, entre 79,1% (‘Campbell Early’) e 197% (‘Hongiseul’) pelo método FRAP, e entre 11,1% (‘Chasselas Rouge’) e 74,5% (‘Flouxa’) pelo método ABTS. Os resultados sugerem que a composição antociânica nas variedades estudadas apresenta uma correlação significativa com a actividade antiradicalar. Assim, considera-se que as uvas destas variedades de videira podem constituir uma fonte potencial de compostos nutracêuticos e com interesse no desenvolvimento de alimentos funcionais.