Purification of Caffeoylquinic Acids from Forced Chicory Roots Using Macroporous Resins: Experimental Investigation and Advanced Modeling of Adsorption Kinetics and Equilibria

Forced Chicory Roots (Cichorium intybus L.) are the main byproduct of the Belgian endive culture and also a great source of caffeoylquinic acids (CQAs), valuable bioactive polyphenols with high potential applications in the cosmetic, food, and pharmaceutical fields. The aim of the present study was to selectively recover chlorogenic acid (5-CQA) and dicaffeoylquinic acid (diCQAs) from a forced chicory roots aqueous extraction. To do so, four different macroporous resins XAD4, XAD7, XAD16, and FPX66 were screened for CQAs adsorption. FPX66 leads to the highest recovery ratio (55% 5-CQA and 73.8% diCQAs) and extract purity (19.6%). CQAs adsorption kinetics and isotherms were performed on FPX66 resin. CQAs adsorption followed a pseudo-second-order kinetic model, while equilibrium data were well-described by a refined multicomponent Langmuir isotherm (R2 0.993–0.999) accounting for competitive adsorption. The total resin capacity for both compounds was 0.55 mmol/g. Better adsorption performances were observed at 25 °C. Optimal CQAs recovery was achieved with an adsorption at pH 2 and a desorption with 50% EtOH eluant. Finally, FPX66 macroporous resin increased CQAs purity 25-fold, from 0.8% to 19.6%. This study highlights the efficiency of adsorption as a green and sustainable technology for purifying bioactive compounds from biomass.