V. V. Kovtunov, N. A. Kovtunova, N. S. Kravchenko
Agrarian Scientific Center “Donskoj”, pos. Nauchnyi gorodok, 3, Zernograd, 347740, Russian Federation
Abstract. This study was aimed at determining the content of tannin in collection samples of sorghum grain and identifying its marker trait for subsequent use in breeding work. To this end, 320 collection samples of sorghum grain harvested in 2016 and 2017 in various ecological and geographical areas were investigated. The experimental plot was located in the Rostov region in the zone of insufficient and unstable moistening. The soil was ordinary carbonate chernozem with the humus content in the arable layer of 3.6%. Fertilizers were not applied. The hydrothermal coefficients over the years of the study ranged from 0.86 to 0.97. Estimation of the tannin content in the grain was carried out in duplicate by the method of determining polyphenols, based on their reaction with vanilla in the presence of hydrochloric acid. The distribution of samples by kernel colouring and their classification in terms of tannin content were performed according to the unified CMEA classifier and CMEA International Classifier for Croplands of the Genus Sorghum Moench. The tannin content in the grain samples under study is shown to vary from 0.04 to 9.20% and to depend on the kernel colour (r = 0.74 ± 0.04). Samples characterized by a white, ivory, yellow, pink and red colour of the kernel contained tannin in the amount of 0.04–3.37% (1.29 ± 0.56% on average), 0.32–4.50% (1.38 ± 1.02% on average), 0.41–4.70% (1.52 ± 0.93% on average), 0.78–7.95% (3.69 ± 1.69% on average) and 1.45–8.89% (4.83 ± 1.92% on average), respectively. Samples with a brown colour of the kernel were characterized by high tannin content values ranging from 2.10 to 9.00% (6.10 ± 2.00% on average). The tannin content varied greatly both within the groups in terms of colour (V = 33–74) and in the total sample (V = 77).
Keywords: sorghum; grain; tannin; antioxidant properties; correlation; nutrition.
Author Details: V. V. Kovtunov, Cand. Sc. (Agr.), leading research fellow (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); N. A. Kovtunova, Cand. Sc. (Agr.), leading research fellow (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); N. S. Kravchenko, Cand. Sc. (Biol.), research fellow (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.).
For citation: Kovtunov V. V., Kovtunova N. A., Kravchenko N. S. Antioxidant Properties of Sorghum Grains. Dostizheniya nauki i tekhniki APK. 2019. Vol. 33. No. 6. Pp. 37–39 (in Russ.). DOI: 10.24411/0235-2451-2019-10609.