Study on the extraction and purification of polyphenols from apple branch and their antioxidative activities

Adsorption and desorption properties of six kinds of macroporous resins were evaluated for isolation and purification of total polyphenols from apple branches. The results showed that X-5 resin was verified to offer the best adsorption capacity and desorption ratio for total polyphenols among the six macroporous resins investigated. Influential factors,such as pH and concentration of feeding solution,strippant,and adsorption isotherm polyphenols,were successively investigated on X-5 resin. The optimum technology were as follows,the sample concentration was 1mg/m L,the adsorption flow rate was 1BV/h,pH of the extracted solution was5.0,the strippant was 70% ethanol,the elution flow rate was 2BV/h. Under the optimum conditions,the purity of total polyphenols increased to 72.36% and the yield was 0.82%. Antioxidative activities of purified polyphenol extracts from apple branches were also studied. The results indicated that polyphenol extracted from apple branches had a strong total reducing power activity and the free radical scavenging abilities on ·OH,DPPH·were excellent.