Evaluation of Phenolic Compounds, Antioxidant Activities and Antioxidant Enzymes of Wild Grape Peel and Pulp

Peel and pulp of grape (Vitis vinifera L.) berries contain a wide range of bioactive compounds that may be responsible for their biological activities. Phenolic compounds, antioxidant capacity and antioxidant enzymes of wild grape accessions from the West Azerbaijan province were investigated in different fractions of berries, i.e., peel and pulp fractions. The total phenol (TP) content ranged from 139.29-843.10 and 151.67-416.91 mg Gallic acid equivalent (GAE) per 100 g in the peel and pulp, respectively. The highest level of antioxidant capacity and antioxidant enzymes activities (Catalase (CAT)and Superoxide dismutase (SOD)) in all the native accessions was observed in peel fraction. Also, principal component analysis (PCA) demonstrated that genotypic effect is more pronounced toward peel antioxidant activity based on 2,2-Diphenyl-1-picrylhy (DPPH) assay and pulp total anthocyanin (TA) of grape berries. The present study displays the potential of native grape accessions studied for improvement of nutritional value through germplasm enhancement programs.