Comprehensive characterization of Chaenomeles seeds as a potential source of nutritional and biologically active compounds

The nutritional profile of seeds from eighteen Chaenomeles species and cultivars was determined using ultra-performance liquid chromatography (UPLC) and atomic absorption spectrometry (AAS). This is the first comprehensive attempt to determine the profile and content of sugars, organic acids, polyphenols, triterpenes, tocochromanols and minerals in Chaenomeles japonica, speciosa and superba seeds. C. japonica wild #3 seeds were characterized by the highest content of sugars (37.32 mg/g seeds, the dominant sugar was glucose) and organic acids (68.22 mg/g seeds, the highest share from galacturonic acid). The most abundant in phenolic compounds was C. speciosa 'Nivalis' (80.90 mg/g seeds), and the polymeric proanthocyanidins were the dominant group in the total phenolic content. The research revealed that Chaenomeles seeds contain 13 different triterpenes and oleanolic acid accounted for an average of 50 % of their total content. Furthermore, they contained 296−1375 μg of amino acids, 1.65–18.9 μg of tocopherols, and 0.25–2.71 μg of tocotrienols per g of seeds. The seeds are a source of all essential amino acids, and alpha homologs dominate among tocochromanols. Moreover, Chaenomeles seeds are low in sodium, but high in potassium (up to 5434 μg/g seeds) and are a good source of microelements (Fe, Cu, Zn and Mn). Therefore, they can be considered as a source of compounds with nutritional and pharmaceutical uses.