Extraction And Purification Of Anthosyanin In Black Mulberry (Morns Nigra Linn) Fruit And Its Characteristic Testing

The anthocyanins is a kind of natural pigment, and belong to flavonoid compouds.Theanthocyanins can dissolve in water.It shows blue in lye,and shows deep purple in theacid.It can stably exist in the acidic conditions.Anthocyanins have many bioactivities,suchas antioxidation,anticancer and bactriostasis. In the thesis,the anthocyanins in blackmulberry (Morus nigra Linn) were extracted and purified,and optimize the extraction andpurification conditions,and assay the antioxidantive activity and bactriostatic activity.The quadratic orthogonal rotation combination design with four factors was used tostudy the effect of ethanol concentration, material fluid ratio, time and temperature byanthocyanidin extraction from black mulberry (Morus nigra Linn) in the research throughultrasonic wave-assisted extraction technology. The regression equation to four factorswere established by software in DPS7.05. Results indicate that the optimal ultrasonicwave-assisted extraction conditions were as follows: ethanol concentration52.46%～55.93%, ratio of solution to material39.51～42.43ml/g, time27.77～32.23min,temperature50.18～52.4℃. On these conditions the extraction efficiency of anthocyanidinis more than67%.Organic reagent extraction and physical purification were used to purify crude extractof anthocyanins of black mulberry(Morus nigra Linn). By analyzing purified products withHPLC, macroporous resin purification was considered a desirable method for purification.Optimum conditions of macroporous resin adsorption and desorption were determined byfurther studying. The results showed that the AB-8macroporous resin was the bestmaterial of anthocyanins purification. About3.5hours and5hours should be taken whenAB-8macroporous resin attained adsorption equilibrium and desorption equilibrium. Theoptimum temperature for adsorption is50℃, the optimum pH for adsorption is6.0, theoptimum pH for desorption is6.0, the optimal concentration of eluent is60%.The antioxidant activity of anthocyanins was evaluated by scavenging free radicals invitro. The of anthocyanins was evaluated by total antioxidant ability and ability forscavenging superoxide anion free radical and DPPH free radical of anthocyanins,andantioxidant activity can also be compared with Vc.The results showed that theanthocyanins have higher ability on total antioxidant and scavenging superoxide anion freeradical than Vc,but Vc have higher scavenging ability on DPPH than anthocyanins.The inhibitory effect on three kinds of bacteria was evaluated by observing inhibition zone and determining the growth curve. The results showed that anthocyanins only havebetter inhibitory effect to E. coli. The MIC and MBC were1.5mg/mL and8mg/mL.Protein electrophoresis analysis results of three strains showed that anthocyanins hadsignificant effect on the protein of E. coli, but had little effect on protein of two other kindsof bacteria.