LAUSR

Grape seeds contain high levels of phytochemicals, that have been associated with a reduced risk of chronic diseases. In this study, the polyphenolic content, antioxidant capacity and antioxidant enzymes activity in the seeds of 20 wild grape accessions native to Iran were investigated. The antioxidant capacity of the wild grape seeds was evaluated by DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and Fe2+ chelating. Total phenolic (TP), total flavanoid (TF) and total proanthocyanidin (TPA) content ranged from 44.86 to 155.1, 23.21 to 131.91, and 10.11 to 26.10 mg/g seed, respectively. All seed extracts showed remarkable DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and Fe2+ chelating ranging from 27.34 to 78.57%, 198.83 to 590.86 µmol TE/g and 23.12 to 62.98%, respectively. Grape seed extracts had the greatest antioxidant enzymes activity guaiacol peroxidase (G-POD), superoxide dismutase (SOD), and catalase (CAT). Based on HPLC analyses, catechin was the most abundant compound identified (25.89 mg/g) for all accessions. Additionally, significant correlations among different antioxidant assays were found. With the high amount of total phenolic content, antioxidant capacity and antioxidant enzymes activity, seeds of P6, P7 and P8 accessions might be evaluated as a nutritional supplement.