Studies On Extraction Purification And Bioactivity Of Anthocyanins From Cichoricum Intybus L.Var. Foliosum Hegi

Cichoricum intybus L.has a large yield and is easy to manage.As a vegetable,it is not suitable for large consumption.Cichoricum intybus L.is used as a raw material to extract anthocyanins,which can utilize red chicory resources more efficiently.In this dissertation,the extraction,purification,composition analysis,stability and biological activities of the anthocyanins from Cichoricum intybus L.were studied.The conclusions are as follows:?1?The anthocyanins from Cichoricum intybus L.were quantified by pH differential method.The quantitative conditions were optimized.The maximum absorption wavelength of this anthocyanin was 520 nm,the extract was ethanol containing 0.1%hydrochloric acid,the pH value of the buffer were 1.0 and 4.5,the reaction temperature was around35°C,and the reaction equilibrium time was 30 min.The average recovery of standard addition was 100.32%and RSD was 1.07%.The method can eliminate the influence of impurities in the solution on the results and can be used for quantitative analysis of the anthocyanins from Cichoricum intybus L..?2?The anthocyanins from Cichoricum intybus L.were extracted by ultrasonic-assisted organic solvent method,the optimum extraction conditions were as followed:liquid-solid ratio was 41:1?mL:g?,ethanol volume fraction was 71%,ultrasonic extraction time was 28 min.Under these conditions,the extraction volume of the anthocyanins was908.596 mg/100g,which was similar to 910.426 mg/100g which was predicted by the model,so the method can be used for practice.?3?The optimum purification conditions of the AB-8 macroporous resin were as follows:adsorption time was 2.5 h,pH value was 2.0,the concentration of crude extract was 342.33 mg/L,flow rate was 2 mL/min and sample volume was 260 mL.Parse time was 1.5 h,eluate was 60%alcohol,flow rate was 2 mL/min and volume was 100 mL.After purification under this condition,the color value of the anthocyanins increased from 5.2 to48.9,which was 9.4 times higher than that of pigment without purification.The composition of the anthocyanins from Cichoricum intybus L.was analyzed by HPLC,the results showed that there were six kinds of the anthocyanins,and the content of3-O-glucoside from the chicory was the highest,which was 646.247mg/100g.?4?The effects of external factors on the stability of anthocyanins from Cichoricum intybus L.were researched.The results were showed that anthocyanins from Cichoricum intybus L.were stable under strong acid conditions,but sensitive to light and high temperature,H₂O₂ can significantly reduce the stability of the anthocyanins,and Na₂SO₃has a bleaching effect on the anthocyanins,Vc has a dual effect on the stability of the anthocyanins,sodium benzoate?C₇H₅NaO₂?and potassium sorbate?C₆H₇KO₂?have little effect on the stability of the anthocyanins,and sucrose has a color-protecting effect on the anthocyanins.Cu²⁺,Fe³⁺and Al³⁺can reduce the stability of the anthocyanins.Na⁺,Mg²⁺,Zn²⁺and Ca²⁺have little effect on the stability of the anthocyanins.K⁺can increase the stability of the anthocyanins.Therefore,the anthocyanins from Cichoricum intybus L.should be preserved in the situations of dark,low temperature and strong acidity,besides,it should avoid contacting with H₂O₂,Na₂SO₃ and metal ions such as Cu²⁺,Fe³⁺and Al³⁺.?5?This experiment comprehensively analyzed the bioactivities of the anthocyanins from Cichoricum intybus L..The results of antioxidant test in vitro showed that the anthocyanins have strong DPPH free radical scavenging ability and Fe³⁺reducing ability.Antibacterial tests showed that the anthocyanins were inhibitory against Staphylococcus aureus,Bacillus subtilis and Bacillus cereus,and had the strongest inhibition against Escherichia coli.The anthocyanins can effectively remove sodium nitrite,and the maximum clearance rate can reach 70.01%.They have a significant blocking effect on the synthesis of nitrosamines,and the maximum blocking rate can reach 85.37%.