| Anthocyanins are polyphenols widely distributed in plants,and they contribute to the brilliant color of blue,red,scarlet in leaves,flowers and fruits.It is reported that they have potentials inhibiting the formation of ROS and scavenging ROS.The blackcurrant is an important fruit which have great biological impact.It contains mineral salts and vitamins in a great amount which have beneficial effect to human health.The blackcurrant is rich in anthocyanins,its juice can be used for coloration.In order to afford the theoretically gists for industrial production and the betterment of this anthocyanin,the isolation,purification,antioxidation and stability of the anthocyanin from blackcurrant mare were mainly studied.This thesis adopted two different methods to extract anthocyanin from blackcurrant. Ethanol as suitable solvent was determined through single factor trials on extraction of anthocyanins from blackcurrant marc.The optimum extraction conditions showed by response surface methodology as follows:extraction at 48℃for 120min with 1:7 ratio of marc to 75% ethanol and the extraction yield is 85.28%.Through experiments,the optimum conditions of enzymatic hydrolysis on blackcurrant marc as follows:temperature 50℃,time 100min,ratio of marc and dissolvent is 1:9,the amount of enzyme is 1%of material,pH value of enzyme solution 5.0 for cellulase hydrolysis,the production of anthocyanin is 86.63%.Temperature 50℃,time 120min,ratio of marc and dissolvent is 1:8,the amount of enzyme is 1.4%of material,pH value of enzyme solution 3.5 for pectinase hydrolysis,the production of anthocyanin is 91.09%.And it defines that pectinase is better than cellulase on extraction.Column chromatography was used to purify feruloylated oligosaccharides.This study confirmed that the best resin to purify anthocyanins from blackcurrant marc was X-5 macroporous resin.The optimum purification conditions were as follows:diameter/height was 1/20,consistence of adsorption liquid was 34mg/mL,pH value was 2.0,adsorption volume was 25mL,flowing rate ether on adsorption or desorption wais 1mL/min,elution of water was 4 column volume,60%ethanol,5 times column volume,the yield reached 89.80%.The color value of purified anthocyanin was 18.26 times higher than that of the begining.Sephadex LH-20 was selected to further separate the sample.Associativng with spectrophotometry,paper chromatography,the result were that the sample can separation two parts,sampleⅡcontains cy-3-rut and dp-3-rut,sampleⅢcontains cy-3-glu and dp-3-glu.The antioxidation of anthocyanin from blackcurrant was determined using hydroxyl free radicals,superoxide anion free radicals,DPPH free radicals,reducing force,lipidosome antioxidation reaction system.The rusults showed that anthocyanin from blackcurrant had strong antioxidative activity,and sampleⅢis better than sampleⅡ,and both better than anthocyanin which purified by resin.The anthocyanin from blackcurrant as experiment material was carried on screening best prescription of stabilizer and contrasting research experiment of its stability.The three stabilizer are 0.09%citric acid,0.08%egg ammonia acid,0.04%glutamic acid.Anthocyanin from blackcurrant is unstable under high temperature,light,and low pH value.The stabilizer can be improved the stability of anthocyanin,citric acid can be improved the resistance to the temperature,egg ammonia acid can be improved the resistance to the light,and the stabilizer can be improved the resistance to low pH value.The stabilizer can be also improved the resistance to the oxidant,reducing agent,sucrose,antiseptic.And egg ammonia acid is best. Stabilizers extend the use area for blackcurrant.
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