Evaluation of Blue Poppy (Papaver somniferum) By-Products as a Sustainable Source of Polyphenols and Antioxidants

The aim of this study was to valorize by-products of blue poppy (Papaver somniferum), a widely used ingredient in the food industry. This study focused on the isolation of bioactive compounds from leaves, stems, roots, capsules and cold-pressed cake. All samples were subjected to conventional solid–liquid extraction (SLE) using ethanol–water solutions of varying concentrations (0, 20, 40, 60, 80 and 96%) as the extraction solvent. The obtained extracts were analyzed for total phenolic content (TP), hydroxycinnamic acids (HCA), flavonols (FL), total flavonoids (TF), condensed tannins (CT) and antioxidant activity. Furthermore, the extracts were subjected to untargeted LC-MS analysis for qualitative characterization. Ethanol concentration significantly influenced the extraction efficiency of bioactive compounds, with the optimal solvent varying depending on the plant part and the specific class of compounds analyzed. Based on TP and TF content, capsule extracts exhibited the highest polyphenol levels. HCAs were detected in extracts from leaves, capsules, and cold-pressed cake. In total, 62 compounds were identified, belonging to various biochemical classes, including organic acids, hydroxycinnamic acids, alkaloids, flavonoids, and fatty acids. Overall, the results indicate that poppy by-products are a valuable source of bioactive components, with promising applications across different industrial sectors.