Composition And Antioxidant Capacity Of Anthocyanins From Hibiscus Syriacus With Different Flower Colors

This thesis studies the material foundation,extraction process and antioxidant ability of Hibiscus syriacus L.,and provides reference for future germplasm resources and selection of targeted antioxidant hibiscus varieties.The results are as follows.1.On the basis of four single factor experiments affecting the extraction conditions of Hibiscus L.pigment,the extraction process of Hibiscus L.pigment was improved,and the best extraction process conditions were obtained to save resources.Combined with the production practice,the most suitable extraction conditions for the factory were determined and verified.The final test results were as follows: solid-liquid ratio 1:38(m L/g),extraction time 37(min),ethanol concentration 74(%)Under this condition,the total flavonoids yield of Hibiscus L.was 14.54 mg /g.2.The results showed that the antioxidant capacity of H.‘Red French Cabaret’(red flower)was higher than that of H.‘Red heart’(white flower).The DPPH free radical scavenging capacity and ABTS free radical scavenging capacity of H.‘Red French Cabaret’ were 1003.95±5.79μmol/kg and 880.68±92.06μmol/kg.3.The composition and content of pigment in Hibiscus hybridus,including H.‘Blueberry Smoothie’,H.‘Red French Cabaret’,H.‘Paeoniflorus’,H.‘Purple French Cabaret’ and H.‘Red heart’,were compared by LC-MS.Nine compounds were preliminarily identified as Apigenin-C-diglucoside,Apigenin-7-O-rutinoside,Vitexin,Kaempferol-O-hexose-C-hexoside,Eriodictyol-7-O-glucoside,Kaempferol-3-O-malonylglucoside-7-O-glucoside,Luteolin-7-O-glucoside,Flavone-O-malonyl-hexoside,Luteolin-7-O-6 "-malonylgalactoside.