Vitis vinifera Turkish grape cultivar Karaerik. Part I: anthocyanin composition, and identification of a newly found anthocyanin.

Background: Grape berries exhibit various beneficial health effects due to the potent antioxidant roles of their phenolic compounds. A new Vitis vinifera grape cultivar (Karaerik) grown in Turkey has attracted growing interest due to its antioxidant phenolic compounds, which have still not been investigated. The phenolic/anthocyanin profile needs to be investigated to ascertain its potential health benefits and market value in the region. The present study therefore involves a detailed characterization of the anthocyanin composition of 'Karaerik' grape berries in conjunction with a determination of the antioxidant capacity value of the phenolics present in the skin and the whole berry.

Results: Total phenolic compounds (average 8.56 and 2.88 g gallic acid equivalent kg fresh weight) and anthocyanin (7.48 and 1.66 g mv-3-glc equivalent kg fresh weight) contents varied significantly in the skin and whole berry. Malvidin-based anthocyanins made the highest contribution to the pigment content of the berry. Accordingly, the major anthocyanin in the skin (average 42.08 mol%) and whole berry (39.98 mol%) was malvidin-3-glucoside (mv-3-glc). In addition, we found strong evidence of the occurrence of sometimes reported malvidin-3-pentoside and particularly of the not previously reported feruloyl derivative of malvidin-3-(6″-feruloyl)-glucoside (mv-3-ferglc) for V. vinifera grapes.

Conclusion: The current study is the first report to profile the anthocyanins of the grape with a detailed description of the rare and novel anthocyanin in V. vinifera grapes. The berry is also a potential source of phenolics/anthocyanins with a high antioxidant capacity value and is worthy of comparison with other V. vinifera grapes. © 2019 Society of Chemical Industry.