In vitro Assessment of Total Bioactive Contents and Antioxidant Capacity of Grape Juices Extracts of Table and Wine Varieties from Algeria and Their Correlations

Abstract

Abstract Vitis vinífera L. is an important source of phenolic compounds, which can prevent disease if included as a part of a diet. In this study, table grape (Cardinal, Muscat, Italia, Gros noir and Red globe) and wine grape juices extracts (Cinsault, Merlot and Syrah) were regarded as studied subject and a reliable method was established to predict their polyphenol, flavonoid, flavonol, condensed tannin, hydrolysable tannin, anthocyanin, ascorbic acid and carotenoids contents. Their antioxidant capacity was determined by using DPPH and reducing power assays. Then chemometrics methods including principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to select the most significant and responsible characteristics for discrimination of grape varieties. Black grape extracts had significantly the highest concentration of ascorbic acid (from 10.09 ± 0.14 to 15.38 ± 0.42 mg/100g), carotenoids (from 0.11 ± 0.01 to 0.58 ± 0.04 mg/100g), total phenols (from 1330.91 ± 9.24 to 1406.7 ± 10.7 mg/100g) and flavonoids (from 165.53 ± 4.7 to 393.22 ± 30.36 mg/100g). Black grape extracts showed the highest antioxidant activity [IC50 varied from 26.44 ± 1.56 to 32.62 ± 0.66 mg/mL] followed by red ones [IC50 ranged from 69.56 ± 7.61 to 80.62 ± 6.58 mg/mL]. Statistics analysis indicated that the levels of bioactive components and antioxidant activity were positively correlated. The PCA applied to the bioactive contents allowed a high degree of grape variety differentiation according to their antioxidant activity. These results showed that grape extracts, can be used in food and pharmaceutical industries as natural antioxidants agents. Keywords: Vitis vinífera L, Grape variety, Extract, Phenolic compounds, Antioxidant activity, Multivariate analysis