The study analyzes the influence of plant growth promoters and biological control agents on the chemical composition and antioxidant activity (AA) in the sprouts of buckwheat. The AA of cv. Kora sprouts was higher than cv. Panda, with 110.0 µM Fe²⁺/g (FRAP—Ferric Reducing Antioxidant Power), 52.94 µM TRX (Trolox)/g (DPPH—1,1-diphenyl-2-picrylhydrazyl), 182.7 µM AAE (Ascorbic Acid Equivalent)/g (Photochemiluminescence—PCL—ACW—Water-Soluble Antioxidant Capacity) and 1.250 µM TRX/g (PCL—ACL—Lipid-Soluble Antioxidant Capacity). The highest AA was found in the sprouts grown from seeds soaked in Ecklonia maxima extract and Pythium oligandrum (121.31 µM Fe²⁺/g (FRAP), 56.33 µM TRX/g (DPPH), 195.6 µM AAE/g (PCL—ACW) and 1.568 µM TRX/g (PCL—ACL). These values show that the antioxidant potential of buckwheat sprouts is essentially due to the predominant hydrophilic fraction of antioxidants. The AA of the sprouts was strongly correlated with total polyphenol content.

This study investigated the influence of biological control agents and plant growth promoters on the chemical composition of the cultivars Panda and Kora buckwheat sprouts. Before sowing, seeds were soaked in solutions containing Bacillus subtilis bacteria, Pythium oligandrum oospores, Ecklonia maxima algae extract, and/or nitrophenols. The sprouts of the Panda displayed higher levels of protein, fat, and dietary fiber fractions than the Kora. Measurable effects of biological control agents (BCAs) and plant growth promoters (PGPs) on the chemical composition of sprouts were also confirmed. Soaking the seeds in a solution containing P. oligandrum oospores resulted in a decrease in the level of crude ash in sprouts, while the addition of nitrophenols increased the level of both crude ash and protein. We also found statistically significant effects of interactions between the cultivar and BCA and/or PGP for each of the examined components.