Study On Extraction And Antioxidant Activity Of Gardenia Yellow Pigment

Gardenia yellow pigment is one of the important natural pigments,and it has a relatively important practical application.In this paper,we use three different extraction methods that are traditional extraction method,ultrasonic and microwave,to extract gardenia yellow pigment and compare the advantages and disadvantages of the three methods,And the stability and antioxidant activity of gardenia yellow pigment were studied.The main contents are as follows:Firstly,the extraction of gardenia yellow pigment was implemented through ordinary extraction method,and the best condition were that the concentration of ethanol solvent was 60%,the time of extraction was 140 min,the temperature of extraction was 50?,and the ratio of gardenia to solvent was 1:14.Under the circumstances,the absorbance was 0.612,and the color price was 38.4.Secondly,extraction of gardenia yellow pigment by ultrasonic-assisted,the best conditions were: the ethanol solvent concentration was 50%,the extraction time was 70 min,the temperature of extraction was 50 ?,and the ratio of gardenia to solvent was 1:12.Under the circumstances,the absorbance was 0.714,and the color price was 45.2.Thirdly,the extraction of gardenia yellow pigment with the aid of microwave extraction method was carried out that the best condition were: ethanol solvent concentration was 60%,the extraction time was 110 s,the extraction power was 500 W,the ratio of gardenia to solvent was 1:12.under the circumstances,the absorbance reached 0.728,the color price was 44.7.Fourthly,The stability of gardenia yellow pigment was discussed which included the intensity of light,pH,temperature level,metal ion oxidant H2O2 and reducing agent Na2SO3 and so on six factors.The results indicated that strong light,high temperature,strong acid,strong base,metal ion oxidant H2O2 and reducing agent Na2SO3 had great influence on the stability of gardenia yellow pigment.Fifthly,the scavenging activity of Gardenia yellow pigment on DPPH and ABTS radicals was investigated by using the IC50 value of scavenging free radicals as the index.The results indicated that Gardenia yellow had positive effects on DPPH free radical and ABTS,and the scavenging effect of free radical scavenging to ABTS was better than that of DPPH radical.The scavenging rate of DPPH free radical and ABTS radical were respectively 60.83?g/mL and 56.78?g/mL.The greater the concentration of the pigment,the greater the antioxidant capacity of the pigment,the faster the reaction rate,and the two reactions meet the first order reaction.