LAUSR

Abstract Alternative raw materials for designing novel products are gaining interest in the scientific area. The aim of this study is to investigate the antioxidant and enzyme inhibitory activities of the extracts obtained from Papaver somniferum L. stalks as well as the determination of chemical composition. Antioxidant capacity was tested by using different chemical methods including radical scavenging, reductive effect, phosphomolybdenum and metal chelating assays. Enzyme inhibitory effect was investigated against cholinesterase, tyrosinase, α-amylase and α-glucosidase. To detect chemical composition, phenolic profile was determined by high performance liquid chromatography (HPLC) as well as total contents of the phytochemicals. The aqueous extract was found to contain high amount of phenolics and flavonoids [9.87 μmol gallic acid equivalents (GAEs)/g dry plant (dp) and 0.09 μmol rutin equivalents (REs)/g dp, respectively]. The methanol and aqueous extracts were also found to contain considerable amounts of (−)-epicatechin and syringic acid. Antioxidant activity tests were resulted in the superiority of the methanol extract. The extracts did not show inhibitory activity on cholinesterases and tyrosinase. Inhibitory activity of the aqueous extract on α-amylase and α-glucosidase were found to be 9.85 and 78.64 μmol acarbose equivalents (ACEs)/g dp, respectively. As a result, P. somniferum stalks, one of the major by-products of poppy cultivation, can be used as the alternative source of antioxidant and enzyme inhibitory compounds in food and medical industries.