Amino-acid composition of seeds of confectionery sunflower varieties bred at the V.S. Pustovoit All-Russian Research Institute of Oil Crops

Large-fruited hybrids and varieties of confectionery and edible sunflower types are widespread in the production of several countries. The protein quality is of particular importance in the characterization of large-fruited sunflower seeds. The value of a protein complex is determined by its amino acid composition. The value of a protein complex is determined by its amino acid composition. We studied the seeds of three large-fruited varieties of confectionery sunflower: Belochka, Dzhinn, Lakomka, cultivated at the experimental station of V.S. Pustovoit of All-Russian Research Institute of Oil Crops in 2017-2019. We determined the amino acid composition of the seed protein on a HPLC-analyzer Sevko&Co APM-1000HT with gradient elution and postcolumn derivatization with ninhydrin. The variety Belochka had the highest content of absolutely dry protein - 21.24 g/100 g, the average protein content for three years was 19.43 ± 0.91 g/100g of absolutely dry matter (ADM), the coefficient of variation was 8.18 %. The protein content of the variety Dzhinn was 19.43 ± 0.11 g/100 g of ADM, the coefficient of variation was 0.78 %. The protein content is more variable in the Belochka variety, while in the Dzhinn variety the oil content is more variable. At the same time, we established that the average values of oil and protein content of these varieties for the years of study are nearly equal. The Lakomka variety has shown stable biochemical parameters for the protein content over two years of cultivation - 17.53 ± 0.15 g/100 g of ADM. There is a strong inverse correlation between the oil content and protein content among the studied varieties, which was r = -0.72. The variety Belochka differs from the other studied varieties. It has the largest amount of essential amino acids (25.48-31.46 g/100 g of absolutely dry matter) and non-essential amino acids (48.33-58.26 g/100 g). The variation of the amino acid content in the Belochka variety was much higher, the coefficient of variation was C = 9-20 %. At the same time, we noted a high homogeneity in protein content (C = 1 %) and amino acid composition (C = 1-15 %) in the Lakomka variety.