Phytochemical profiles and antioxidant activity of some grape accessions (Vitis spp.) native to Eastern Anatolia of Turkey

Phytochemical profiles and antioxidant activity of four historical grape accessions (‘Kuzu Kuyrugu’, ‘Miskali’, ‘Erkek miskali’, and ‘Kirmizi Kismisi’) grown in Igdir province located in Eastern Anatolia Region of Turkey were examined. Levels of vitamin C, organic acids (citric acid, tartaric acid, malic acid, succinic acid, fumaric acid), sugars (fructose, glucose), phenolic acids (catechin, rutin, quercetin, chlorogenic acid, ferulic acid, o-coumaric acid, p-coumaric acid, caffeic acid, syringic acid, vanillic acid, and gallic acid), and antioxidant capacity (Trolox Equivalent Antioxidant capacity, TEAC assay) were determined. Accession was found to be important source of variation for all the parameters identified above (P<0.01). Among the grape accessions analyzed, ‘Kuzu Kuyrugu’ had the predominant vitamin C (47.19 mg/100 g), chlorogenic acid (2.687 mg/L), ferulic acid (1.303 mg/L), o-coumaric acid (1.317 mg/L), and syringic acid content (1.687 mg/L). The highest citric acid (55.360 mg/L), fructose (10.36 g/100g), glucose (11.51 g/100g), and catechin (1.353 mg/L) were recorded in ‘Miskali’ genotype. ‘Kirmizi Kismisi’ was determined to be the accession with the highest tartaric acid (21.29 mg/L), succinic acid (0.94 mg/L), and caffeic acid (2.137 mg/L) levels. ‘Erkek Miskali’ accession produced the paramount contents for fumaric acid (0.42 mg/L), rutin (2.477 mg/L), quercetin (0.447 mg/L), and vanillic acid (0.313 mg/L). The investigated grape genotypes showed notable levels of sugars, organic acids and phenolic compounds. These accessions could be valuable in breeding programs for improving grape quality and nutrition, as well as enhancing commercial worth and production of the grapes in Igdir province of Turkey.