E. V. Ostroukhova, I. V. Peskova, M. A. Vyugina
All-Russian National Research Institute of Viticulture and Winemaking «Magarach» of RAS», ul. Kirova, 31, Yalta, Respublika Krym, 298600, Russian Federation
Abstract. Due to the destructive effect of free radicals on the human body, the search for the most promising natural antioxidant sources that can be used in food products is highly relevant. The aim of the work was a comparative analysis of grape cultivars, grown in the western foothill and seaside region of Crimea, according to the content of stilbenoids and flavonols. We investigated must, aqueous alcoholic extract of vine and peel of the grape varieties Aligote, Rhine Riesling, Rkatsiteli, Cabernet Sauvignon, Merlot, Citronny Magaracha, Riesling Magaracha, Podarok Magaracha, Antey Magarachsky, Krasen, Golubok, selected in 2013–2015. The analysis was carried out by HPLC using Agilent Technologies system; the significance of differences was assessed according to the criterion of Mann-Whitney. The concentration of flavonols in extracts of grape peel was higher than in must and vine extracts on average 35 and 14 times, respectively, and varied from 61.1 to 364.0 mg/dm3 depending on the cultivar. Berry peel extracts of Cabernet-Sauvignon were particularly rich in quercetin and kaempferol; the average concentration was 18.7 mg/dm3, which was 2.3 times more than in other grape cultivars. Berry peel extracts of Podarok Magaracha was rich in quercetin glycosides (353.7 mg/dm3), which was 1.7–6.5 times more than in other grape cultivars. The concentration of stilbenoids in berry peel extracts and in the must did not exceed 3 mg/dm3, while in shoot extracts it ranged from 22.6 mg/dm3 (Riesling Magaracha) to 118.8 mg/dm3 (Cabernet-Sauvignon). Vine stilbenoids were represented by dimeric forms of resveratrol, mainly epsilon-viniferin, by 46–94%. A high share (41%) of trans-resveratrol and the highest content of piceid were detected in vine extracts of Aligote and Rhine Riesling. Resveratrol predominated in the stilbenoid complex of the grape peel of the European cultivars (on average 64%), while epsilon-viniferin predominated in the complex of selection cultivars (on average 70%). Vines of Cabernet-Sauvignon and Merlot can serve as promising sources of the antioxidants of the stilbene series; while berry peels of Podarok Magaracha and Cabernet-Sauvignon are an excellent source of flavonols.
Keywords: grape cultivars; must; peel; vine; HPLC; stilbenoids; flavonols; concentration.
Author Details: E.V. Ostroukhova, D. Sc. (Tech.), head of laboratory (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); I.V. Peskova, Cand. Sc. (Tech.), leading research fellow; M.A. Vyugina, junior research fellow.
For citation: Ostroukhova E.V., Peskova I.V., Vyugina M.A. Comparative Analysis of Grape Cultivars as Sources of Biologically Active Compounds: Stilbenoids and Flavonols. Dostizheniya nauki i tekhniki APK. 2019. Vol. 33. No. 1. Pp. 45–49 (in Russ.). DOI: 10.24411/0235-2451-2019-10111.