Study Of The Separation Process And Antioxidant Capacity Of Polyphenol From Robinia Pseudoacacia L. Flowers

Robinia pseudoacacia L. is one of the most common trees of the artificial shelterforest in the west of China. Robinia pseudoacacia L. is widely cultivated on a nationscale. Although the florescence of Robinia pseudoacacia L. is short, Nevertheless theyield of Robinia pseudoacacia L. flower is considerable. Robinia pseudoacacia L.flower could be applied to extensively fields, which provides a certain value in bothmedical use and edible use. Plant polyphenol presents a certain bioactivity such asantioxidation and anticancer, which could benefit human health. The development ofRobinia pseudoacacia L. flower has already become focal issue in related fields.Robinia pseudoacacia L. flower servers as the raw material in the research of theextraction of plant polyphenol. The optimazation of the ultrasound-assisted extractionand soxhlet extraction of polyphenol from Robinia pseudoacacia L. flower is studiedby means of Comprehensive weighted scoring method and Orthogonal test method. The Oxygen Radical Absorbance Capacity and the DPPH radical scavenging capacityof the extract through different extraction methods are compared in this research.NK-Ⅱ macroporous resin is applied to purifing the crude extract by means ofDynamic adsorption and Dynamic elution. The composition of the eluent is testedwith HPLC method. The results are as follows:1、 The optimum conditions of ultrasound-assisted extraction are determined asfollows: ethanol concentration40%, the solid/liquid ratio1:20(g:ml), extractiontemperature75℃, extracting time30min, ultrasonic power160W. The optimumconditions of soxhlet extraction are determined as follows: extracting time3h,solution temperature90℃, solid/liquid ratio1:60(g:ml).2、 The extract of the ultrasound-assisted extraction provides stronger OxygenRadical Absorbance Capacity and DPPH radical scavenging capacity than that ofthe soxhlet extraction.3、 The optimum conditions of Dynamic adsorption are determined as follows: theconcentration of the extract should be100mg/L and the flow rate should be 2mL/min.80mL of the80%ethanol water should be applied to eluting thesaturated resin.4、 The composition of the eluent is tested with HPLC method, the results reveal thatRobinia pseudoacacia L. flower contains a certain amount of rutin, gallate,caffeic acid, quercetin and catechinic acid.