A Comparative Study Of Antioxidant And Electrochemical Properties Of The Flavonoids Isomers

Natural flavonoid compounds widely found in plant roots,stems,leaves and fruit,they have important pharmacological activity,can treat cardiovascular disease,cancer,endocrine disorders and other diseases,which attracted widespread attention at home and abroad.The antioxidant activity of flavonoid compounds is one of the hot research topic.We through survey of flavonoid compound antioxidant ability strong or weak,found in the historical research on the structure-activity studies the main conclusion is the more phenol hydroxyl number the stronger oxidation ability.Found that the most significant factors influencing flavonoids antioxidant capacity should be o-phenolic hydroxyl group in the structure.To this end,we screened the three pair isomers of flavonoids with structural contrast,and from the angle of the electrochemical oxidation resistance to its size.This paper mainly studied the following aspects:1.A new method for the indirect determination of hydroxyl radical(OH)production rate was investigated.The method can be used to evaluate the antioxidant ability of antioxidant.The method was proved by ascorbic acid as antioxidant.2.The inhibition ratios of six materials on DPPH and hydroxyl radical were determined by spectrophotometric and kinetic analysis method.According to the antioxidant of flavonoids were compared and structure-activity analysis,obtained o-phenolic hydroxyl is to make flavonoid antioxidant capacity greatly improved mainly due to a conclusion.The differences of electrochemical reactions and the oxidized order of six substances were studied using CV,the reason about the differences of antioxidant was explained on the other hand.3.Baicalein because of have two o-phenolic hydroxyl and a super antioxidant capacity.And in this paper,we study the electrochemical properties of baicalein,set up a new method of DPV to detect it.The method is not only simple and easy to operate but also both the high sensitivity and the low detection limit of the advantages.We apply this method for the determination baicalein medicines and simulation urine.