Polyphenolic diversity in Sorbus: chemotaxonomic approach to hybridization and secondary metabolite production

The genus Sorbus exhibits considerable diversity due to processes such as hybridization, polyploidy, autopolyploidy and apomixis, which also influence the production of polyphenolic compounds [ 1 ] [ 2 ]. Our previous study showed the chemotaxonomically significant connection between flavonoids and hybridization [ 3 ]. To achieve a comprehensive chemotaxonomy of Sorbus , a detailed phytochemical analysis of procyanidins and phenolic acids was performed. Leaf material was collected from Sorbus accessions at ten locations in Bosnia and Herzegovina, representing both the parent species ( S. aria , S. torminalis , S. aucuparia ) and their hybrids ( S. aria×S. torminalis , S. aria×S. aucuparia ). Besides 23 flavonoids [ 3 ], a total of 7 phenolic acids and 5 procyanidins were identified using the LC-MS method based on UV spectral data, MS fragmentation patterns and commercially available standards. Chlorogenic acid (0.455-5.204 g/100 g dry extract) and 1,5- O -dicaffeoylquinic acid (0.112-1.998 g/100 g dry extract) were the most abundant. The most abundant procyanidins were type B trimers (0.464-6.334 g/100 g dry extract) and dimers (0.224-2.509 g/100 g dry extract), with a type B procyanidin trimer found specifically in the endemic S. bosniaca and its parent species S. aria . Of note, the B-type procyanidin dimer was not present in hybrids of S. aria×S. torminalis . Chlorogenic acid and caffeoylquinic acid were present in all samples, with neochlorogenic acid being specific only for the parent species of the Tormaria group, S. torminalis . The results suggest that each polyphenol group undoubtedly has an impact on chemotaxonomy and the relationships between hybridization, polyploidy and secondary metabolites production ([ Fig. 1 ]). Fig. 1 The relative content of phenolic acids, procyanidins, and flavonoids (classified according to their structure) in the ethyl acetate fractions of the studied Sorbus accessions. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany