Static, Kinetic, and Isotherm Adsorption Performances of Macroporous Adsorbent Resins for Recovery and Enrichment of Bioactive Procyanidins from Cranberry Pomace.

Abstract

This study examined the ability of five Amberlite resins coupled with ultrasound-assisted water extraction for the recovery and enrichment of bioactive procyanidins and total phenolics from cranberry pomace. Static adsorption showed that XAD-7HP had the highest adsorption capacity for procyanidins (52.2mg/g resin) and total phenolics (99.1mg/g resin) whereas XAD-761 had the lowest. Adsorption of procyanidins fitted better to pseudo-second-order kinetics than pseudo-first-order kinetics. Isotherm adsorption on XAD-7HP suggested that Langmuir isotherm was a better model to describe the adsorption of procyanidins while Kemkin-Pyzhev equation was better for total phenolics based on higher coefficient of determinations (R2 ). Dynamic tests on XAD-7HP suggested that the flow rate of 7 and 8 mL/min were the optimum conditions for adsorption and desorption of procyanidins, respectively. Measurements using HPLC revealed that adsorption increased the contents of procyanidins and total phenolics by 4.57- and 4.73-folds, respectively, compared to the initial extracts. This research showed that Amberlite XAD-7HP resin adsorption coupled with ultrasound-assisted water extraction is an efficient method to separate and concentrate procyanidins from cranberry pomace.