Study of the textural properties of non-ionic resins and their influence on polyphenol adsorption and desorption

Macroporous resins are employed for the purification of polyphenolic extracts. However, the relationship between the adsorption and desorption and the textural properties remains unexplored. Thus, we evaluated the textural properties of HP-20, XAD-16 and SP-825 resins and their impact on adsorption and desorption of specific polyphenols like gallic acid, epigallocatechin, and procyanidin B2. The HP-20 resin exhibited a type II isotherm with macroporous structure, while XAD-16 and SP-825 resins displayed type IV isotherms, typically associated with mesoporous materials. The HP-20 resin demonstrated superior adsorption capacity and rupture points for epigallocatechin (2.37mg/g, 124min) and procyanidin B2 (1.29mg/g, 136min) compared to SP-825 and XAD-16. Contrary, the SP-825 resin exhibited the highest adsorption capacity (5.34mg/g) and rupture point (68min) for gallic acid. However, the desorption was more efficient when HP-20 resin was used for all specific polyphenols. Therefore, for an efficient purification process is necessary to consider the chemical structure of the polyphenol and the textural properties.