Extraction,Purification And Qualitative Analysis Of Anthocyanins From Purple Cabbage

Anthocyanin is a kind of water-soluble flavonoids, a natural pigment, which plays the ruling role in coloring of plants and fruits. Nowadays, more and more people accept the concept that healthy living is the most important, so our demand for natural pigment is increasing. As a kind of natural pigment, Anthoyanins with huge economic benefit in food industry, and immeasurable potentiality in cosmetics and bio-pharmaceutical field. Consequently, there are more and more researches about anthocyanin and anthocyanin-rich plants and fruits.In this paper purple cabbage was used as materials, to study on optimization of extraction process, anthocyanin crude extract purification and the anthocyanin component analysis. The main results were as follows:1. Using single factor optimization to select the best extraction reagent, concentration of extraction agent, extraction time, liquid/solid ratio, the p H value of extraction agent, temperature and extraction times, the results of significance analysis showed that the extraction reagents, liquid/solid ratio, concentration of extraction agent, extraction time and extraction times significantly affect anthocyanins yield.2. Taking into account the results of single factor experiments, liquid/solid ratio, extraction time and concentration of extract agent were selected for further optimization by using the response surface method(RSM), three factors and three levels experiment were carried out. The results showed that the optimum conditions for extraction of anthocyanins from purple cabbage were: liquid/solid ratio =16.90 ml/g, extraction time=40.00 min, methanol concentration=59.51%, and anthocyanins yield was 1.06817 mg/g.3. Three kinds of macroporous resins(AB-8, NKA-9, X-5) were used for purifying the crude extraction, as a result of the static adsorption and desorption results, AB-8 resin was more suitable than the other two kinds of resins. Dynamic adsorption and desorption experiments showed that the optimum anthocyanins crude extract flow rate was 4.5 ml/min, 60%(v/v) ethanol was used as eluent solution, and optimum flow rate was 2.0 ml/min.4. Purified anthocyanins solution was concentrated before investigating compositions by using HPLC-MS. The results showed that two types of anthocyanins were identified, including Cyanidin anthocyanins and Delphinium anthocyanins. Further investigation showed that there were 8 kinds of anthocyanins present in purple cabbage, the one was Delphinium-3-glucoside, the other seven all were Cyanidin anthocyanins.