Comparative study of five different macroporous resins as separators and purifiers of apple polyphenols
The adsorption rules of five kinds of macroporous resins i.e., XDA-1, XDA-5, XAD-16, AB-8 and LH-20, either local or exotic, were used to study the isolation and purification of apple polyphenols in order to determine the appropriate solution to provide a technical basis for the effective measure on apple renewable resources. The results indicated that different types of macroporous resin had a different maximum adsorption capacity (Max A) for apple polyphenol components, and among that XDA-1 had the highest Max A for total phenols with a measured value of 38.90 mg g-1 and a model fitting value of 38.26 mg g-1 (R2=0.9684), LH-20 had the highest Max A for flavanols with a measured value of 37.75 mg g-1 and a model fitting value of 37.98 mg g-1 (R2=0.9806). XAD-16 had the highest Max A for proanthocyanidins with a measured value of 29.60 mg g-1 and a model fitting value of 30.05 mg g-1 (R2=0.9766). The equilibrium time for apple polyphenol components to achieve Max A varied with different types of macroporous resin: it took 9 h for total phenols to reach 98.43% of Max A through XAD-16 while 10 h for flavanols to reach 93.18% of the Max A through AB-8 and proanthocyanidins to reach 94.86% of Max A through XDA-5. The desorption efficiency of apple polyphenol components also significantly varied according to the different concentrations of ethanol when XAD-16 reached adsorption equilibrium and the ratio for 50% ethanol to desorb total phenols was 95.05- 102.77% while for 70% ethanol to desorb both total phenols and proanthocyanidins, it went over 90%. For efficient purification of apple polyphenols while considering production cost, separation efficiency and product safety, XAD-16 macroporous resin with 50% ethanol was suggested as the best desorption solution.
Zhang, Qianru, Yin, Rong, Duan, Zemin and Wang, Xianping (2018). Comparative study of five different macroporous resins as separators and purifiers of apple polyphenols. Acta Hortic. 1208, 347-354
apple polyphenols, macroporous resin, adsorption capacity, desorption efficiency