Accumulation of Phenolic Compounds and Antioxidant Capacity during Berry Development in Black ‘Isabel’ Grape (<i>Vitis vinifera</i> L. x <i>Vitis labrusca</i> L.)

• Main Authors: Aynur Kurt-Celebi, Nesrin Colak, Sema Hayirlioglu-Ayaz, Sanja Kostadinović Veličkovska, Fidanka Ilieva, Tuba Esatbeyoglu, Faik Ahmet Ayaz
• Format: Article
• Language: English
• Published: MDPI AG 2020-08-01
• Series: Molecules
• Subjects: grape; anthocyanins; proanthocyanidins; seed; skin; development
• Online Access: https://www.mdpi.com/1420-3049/25/17/3845

Grapes are one of the most economically important fruits in the world and are of considerable benefit to human health due to their phenolic compounds. The black ‘Isabel’ grape (<i>V. vinifera</i> L. <i>x </i><i>V. labrusca</i> L.) is widely grown in the Black Sea region of Turkey, where it is attracting increasing interest. The aim of this study was to investigate phenolic compounds and antioxidant capacity (DPPH (2,2-diphenyl-1-picrylhydrazyl) and CUPRAC (CUPric Reducing Antioxidant Capacity)) in the grape during berry development, which has been not reported yet from the region. A trend towards an increase in total phenolic compounds, flavonoid, and anthocyanin contents and antioxidant capacity values was observed from un-ripened to overly ripened berries. In addition, anthocyanins in berries and proanthocyanidins seeds were characterized during berry development. Accordingly, malvidin-3-<i>O</i>-glucoside was the major anthocyanin in skin (1.05–1729 mg/kg fresh weight (fw)) and whole berry (0.23–895 mg/kg fw), followed by the content of peonidin-3-<i>O</i>-glucoside (0.98–799 mg/kg fw and 0.15–202 mg/kg fw, respectively). After veraison (onset of ripening or change of color in the grape berries), all proanthocyanidins showed a gradual decrease through ripening. The results showed that anthocyanins and proanthocyanidins in the grape showed significant stage-dependent changes with positive or negative strong correlations. Considering the phenolic compounds, an optimum harvest date of the grape might be suggested between mid-September and mid-October (263 and 293 DAFBs).