Research On Extraction、Purification And Antioxidant Effects Of Polyphenols In Apple Pomance

Apple polyphenols are a class natural products, which mainly concentrate in apple peels and fruitseeds and have many kinds of bioactive functions, such as antioxidant、anti-aging、anti-tumor and so on.These polyphenols entered into apple pomace along with apple juice and cider processing. China, as oneof the biggest countries to product and process apples, millions tonnes of apple pomace every year.Probably30%of the apple pomace would be used as fertilizer and animal feed, the residual would bewasted as garbage. There are about10-15million apple pomace flow into the environment every year. Itis not only a waste of resource, but also pollute environment. Therefore, it is significantly important tocarry out high quality research use of apple pomace polyphenols. On the one hand, we can increase theadded value of deep processing products; on the other hand, we can extend apple processing industrychain and turn the waste into treasure. The work has important economic and social value.Residues from juice extraction of apple were used in this paper. We optimized the extracttechnology by Ultrasound-assisted ethanol extraction; purified phenolic compounds by macroporousadsorptive resin （NKA-9）; identified the composition of apple polyphenols using the infrared and highperformance liquid （HPLC）; investigated the antioxidation activity in vitro by evaluations ofhydroxyl radical scavenging activity, superoxide radical scavenging activity, FRAP radical scavengingactivity and ABTS radical scavenging activity; established the model of Caenorhabditis elegans（C.elegans） and researched theeffects of polyphenols from apple pomance on C.elegans under stressto reflect the antioxidant mechanism in vivo. The main content and research results are as follows:1．The optimization of ultrasound-assisted extraction technology of polyphenols from applepomace by response surface methodology, On the basis of single-factor test, Response surfacemethodology was used to investigate the effects of processing parameters, including extraction time,temperature, ultrasound power and solvent/material ratio. The extraction rate of polyphenols was chosenas response value, mathematical model was established by implementing four factors and three levels.the optimum technological conditions was extraction time of10min, extraction temperature of65℃,ultrasonic power of503W, solvent/material ratio of1:30（g/mL）. The extraction ratio of applepolyphenols was up to4.53mg/g.2．NKA-9macroporous adsorptive resin can putify the apple polyphenols, under appropriateparameters the apple polyphenol purity was72%.Then we analysised and detected the constituent of theapple polyphenol by Infrared Spectroscopy and HPLC, the results indicated that the most abundantelements was quercetin and its glycosides, accounting for59.54%of the total phenolic, followed byphlorizin category which accounted for22.75%. The content of other polyphenols such as procyanidinB2、epicatechin、chlorogenic acid and caffeic acid was low, which accounted for less than18%.3．The antioxidant test in vitro showed that apple polyphenols had significant ABTS radicalscavenging activity, DPPH radical scavenging activity, superoxide radical scavenging activity,and alsosignificant in reducing power. Apple polyphenols have stronger effect on radical scavenging activity and reducing power than vitamin C in the same concentration. The PCL test indicated that the radicalscavenging activity of per gram apple polyphenols equivalent of3.28g vitamin C.4．Research the effect of apple pomace polyphenols on the aging of C.elegans, measure the longestlife, average life, reproductive capacity and the variation of reactive oxygen of C.elegans underdifferent stress conditions. The results showed that apple pomace polyphenols significantly extend thelife of C. elegans, the lifespan of C. elegans had an extension of43.3%when the concentration of applepolyphenols was100μg/mL and no significant effect on fecundity. Similarly, the pomace polyphenolsof100μg/mL significantly extend the lifespan and the level of reactive oxygen in vivo of C. elegansunder different stress.In summary, the research studied the extraction and purification of polyphenols from apple pomacepowder, optimized the optimum parameters of ultrasonic assisted extraction of polyphenols from applepomace; used infrared spectroscopy and anti-HPLC to analysis the composition of polyphenolssubstances; used different antioxidant systems to evaluate the antioxidant activity in vivo and in vitro ofapple pomance polyphenols; revealed the antioxidant effects mechanism of apple pomance polyphenolsby extending the life of C. elegans under different stress conditions.