| Whereas the current development of apple industries, and the multiple efficacies of apple polyphenols, the research and exploiture of apple phenolic substances is meaningful, it can increase the added value of apple and ameliorate industrial structure in apple production. Meanwhile, it can improve the income of fruit growers. In the researching theme, the issue that how does the apple polyphenols in local district change in the growth is done firstly, aiming to determine better fruit thinning period and use the polyphenol resource effectively. Next, according to solvent choice, single factor experiments, response surface analysis and resin purification, a better purification process which is the basic of pilot process is accomplished. Through with HPLC, the adsorption state about optimization resin is analyzed. Finally, using precipitation characteristics of phenolic substances, to find out the relationship between antioxidant properties and phenolic substances, and investigate how to vary about antioxidant properties when the metal ions are present.Through the issues, the content of the total polyphenols and the total flavonoids have a higher value after two weeks when the flowers drop. The apple can be properly thinned at that time to get high content of phenolic substances from the fruit thinning extract.Taking single factor experiments, multifactor response surface analysis, when the extracting solution is compounded by methanol, ethanol, water (1:1:1), optimum extraction conditions of the total phenols and the total flavonoids are below: the temperature is 94.4℃and 74.95℃respectively, the time is 14.15min and 10.68min separately, the ratio of liquid and material is 30.2mL/g. A better extract condition of the total flavanols is temperature 75℃, the extraction time 14.5min, 7.64mL/g liquid-material ratio. In the purification process of resin, LX-1 is a better resin for separation of polyphenols.The dynamic experimental study about LX-1 resin(67cm× 2.1cm)show that when the liquid adsorption velocity is 4.7mL/min, 600mL and 450mL adsorption liquid can reach state of the resin adsorption saturation for the total phenols and the total flavonoids. Dynamic adsorption capacity of the resin about the total phenolics and the total flavonoids are 0.66mg/mLresin and 0.175mg/mL resin; 85% ethanol, a flow rate of 3.5mL/min eluate, the total phenolics and the total flavonoids can be fully cleared by 300mL eluate. The adsorption liquid and eluate from the resin purification are analyzed by high performance liquid chromatography, finding that LX-1 resin can be used in the preparation of pure apple polyphenols.After the study of polyphenols characters, the results show that magnesium salt can decrease more total polyphenols, but aluminium salt is better for the deposition of flavanols. In alkaline environment, the precipitation of two salts is much stronger. Apple polyphenols is effective free radical scavenger, cleanup rate of DPPH·relates with the content of total polyohenol. However the content of total flavanol (include catechin and polyprocyanidin) affects obviously the cleanup rate of ABTS·~+. When the total polyohenol content is low, aluminium and magnesium salt can promote free radical cleanup.
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