Bilalov, ElchinMartins, Cláudia FilipaCosta, Mário RuiDias, Rolando2025-04-242025-04-242025Bilalov, Elchin; Martins, Cláudia Filipa; Costa, Mário Rui; Dias, Rolando (2025). Separation of Bioactive Compounds in Olive Leaf with a Pyridyl-Functionalized Adsorbent and Hydroalcoholic Solvents. Industrial & Engineering Chemistry Research. ISSN 0888-5885. 64:10, p. 1-140888-5885http://hdl.handle.net/10198/34439The separation of different types of bioactive compounds in olive leaf is demonstrated with a tailored adsorbent functionalized with pyridyl moieties and sorption−desorption processes developed to use only hydroalcoholic solvents. The competitive binding isotherms of mixtures of vanillic acid, oleuropein, quercetin, maslinic, and oleanolic acids in water/ethanol solvents, with the composition ranging from 50/50 up to 100% ethanol, prove the feasibility of the separation of such different classes of molecules. The bioactive compounds in two industrial olive leaf extracts with different crude compositions were separated with the pyridyl-based polymer particles in packed columns, employing multicycle sorption/desorption processes. A polyphenol-rich extract was subjected to separation, resulting in the isolation of fractions containing varying concentrations of specific compounds. For example, a fraction enriched with oleuropein exhibited a concentration of approximately 80% (an enrichment factor of ∼4 in comparison with the crude extract), while glycosylated flavonoids were present at a concentration of around 60% in another fraction (an enrichment factor of ∼12). Additionally, aglycone flavonoids were present in fractions at a concentration of approximately 83% (an enrichment factor of ∼49). On the other hand, the separation of polyphenols and triterpene acids in an olive leaf extract with a high triterpene content was also demonstrated, with a ratio of flavonoids to triterpenoids of approximately 23 in isolated fractions, as compared to approximately 1 observed in the crude extract. The developed approach yielded luteolin with an enrichment factor of approximately 7. These novel achievements are intended to contribute to sustainability and a circular bioeconomy through the efficient industrial valorization of agricultural by products.engEthanolPolyphenolic compoundsBioactive compoundsDesorption processEnrichment factorsFlavonoidFunctionalizedLeaf extractsOleuropeinOlive leafPyridylSorption/desorptionFlavonoidsjournal article10.1021/acs.iecr.4c046221520-5045