Application of biodegradable cholinium ionic liquids for the extraction of 5-hydroxymethylfurfural (HMF) from honey

Aleksandar Marić; Pavle Jovanov; Slobodan Gadžurić; Tatjana Trtić-Petrović; Marijana Sakač; Aleksandar Tot; Marko Bertić; Milan Vraneš

doi:10.1039/d3ra06077b

Application of biodegradable cholinium ionic liquids for the extraction of 5-hydroxymethylfurfural (HMF) from honey

RSC Adv. 2023 Nov 7;13(46):32714-32721. doi: 10.1039/d3ra06077b. eCollection 2023 Oct 31.

Authors

Aleksandar Marić¹, Pavle Jovanov¹, Slobodan Gadžurić², Tatjana Trtić-Petrović³, Marijana Sakač¹, Aleksandar Tot⁴, Marko Bertić⁵, Milan Vraneš²

Affiliations

¹ Institute of Food Technology in Novi Sad, University of Novi Sad Bulevar Cara Lazara 1 21000 Novi Sad Republic of Serbia aleksandar.maric@fins.uns.ac.rs.
² Faculty of Sciences, University of Novi Sad, Department of Chemistry, Biochemistry and Environmental Protection Trg Dositeja Obradovića 3 21000 Novi Sad Republic of Serbia.
³ Laboratory of Physics, Vinča Institute of Nuclear Sciences, University of Belgrade, National Institute of the Republic of Serbia 11001 Belgrade Republic of Serbia.
⁴ Applied Physical Chemistry, Department of Chemistry, KTH Royal Institute of Technology Stockholm SE-10044 Sweden.
⁵ University of Freiburg Fahnenbergplatz 79085 Freiburg im Breisgau Germany.

Abstract

5-Hydroxymethylfurfural (HMF), a Maillard reaction product, can be formed when honey is subjected to heat treatment or a long storage time, becoming volatile and toxic depending on its concentration. The fact that, until today, there is no literature data on the extraction of 5-hydroxymethylfurfural (HMF) from honey using ionic liquids directed the investigation of the influence of biodegradable cholinium ionic liquids on the formation of aqueous biphasic systems and the application of these systems for the extraction of HMF from honey. The influence of anions of synthesised ionic liquids on the construction of biphasic systems in which an inorganic salt was used as a salting agent was investigated. Then, the extraction of HMF in these systems was examined, and the mechanisms of HMF extraction using ionic liquids were explained using computer simulations. Examining the effect of cholinium ionic liquids (choline chloride ([Ch][Cl]), cholinium nicotinate ([Ch][Nic]), cholinium propionate ([Ch][Prop]), and cholinium butyrate ([Ch][But])) on the formation of aqueous biphasic systems by comparing the phase diagrams, it was concluded that the ability of ionic liquids to form an aqueous biphasic system with tripotassium phosphate (K₃PO₄) decreases in the following order: [Ch][But] ≈ [Ch][Prop] > [Ch][Nic] > [Ch][Cl]. By applying all tested aqueous biphasic systems for the extraction of HMF from honey, an extraction efficiency of more than 89% was achieved. Complete extraction was achieved using the extraction system with [Ch][But], while the weakest ability to extract HMF was exhibited by the system with [Ch][Cl]. The mechanisms of HMF extraction using ionic liquids are explained on the basis of the optimised structures of the ionic liquid systems with HMF, together with the visualisation of non-covalent interactions, and on the basis of the calculated binding energies ΔG_bin, which can be used as a good predictor of the extraction potential of newly synthesised ionic liquids.