Extraction And Purification Of DMY In Ampelopsis And The Property Research

Ampelopsis is rich in flavonoids, of which dihydromyricetin content is up to about 30%. Dihydromyricetin is a polyphenol hydroxy dihydro flavonol, also known as the snake grape essence, double hydrogen waxberry bark, flavonoids, dihydromyricetin reputation for its special antibacterial, antioxidant and other physiological functions, and has good medicinal value, great potential for development. China has rich resources of Ampelopsis grossedentata, but Ampelopsis grossedentata most used for bubble drink, Ampelopsis grossedentata provides us a path to develop this natural materials, opened up a way to get more high value-added products. The Ampelopsis grossedentata as raw material, of dihydromyricetin pigment extraction and purification process were studied, and of dihydromyricetin pigment and chemical properties were analyzed, dihydromyricetin provides data base for deep development and application.Using high performance liquid chromatography, the establishment of the dihydromyricetin element determination conditions: Agilent tc-c18 stainless steel column(250mm×4.6mm) imitating color spectrum column and methanol water is 72:28(0.1% acetic acid), flow rate is 1.0ml/min, the sample size is 20μL, the column temperature is 35℃.The hot water extraction method of dihydromyricetin in ampelopsis grossedentata extraction process was researched. Ampelopsis grossedentata content of dihydromyricetin by 30.5%. On the basis of single factor experiment, the response surface optimization was carried out on dihydromyricetin extraction process, and the optimum extraction conditions were obtained as follows: the extraction temperature was 78℃, the extraction time was 64 min, pH was 8.3.In addition to the impurity concentration of dihydromyricetin red pigment extraction liquid, the membrane separation technology was adopted. Contrast the microfiltration membrane A and microfiltration membrane B of dihydromyricetin element leaching liquid impurity removing effect, select the average membrane flux was 139.5L/(m2.h), DMY transmittance was 97.5%, solid shaped object interception rate was 37.3%. Contrast the nanofiltration membrane DK and nanofiltration membranes DL of dihydromyricetin concentration effect, select the nanofiltration membrane DL average flux was 16.2L/(m2.h), DMY transmittance was 99.2% and solid shape material retention rate was 94.2%.Freeze drying method was used to study the freezing and drying conditions of dihydromyricetin.The optimum technological parameters of freeze drying method were determined: the temperature of the heating plate was 65℃, the vacuum degree was 50 Pa, the material thickness was 8mm, the best freezing and drying efficiency was 140.5g/m2.h.The physical and chemical properties of dihydromyricetin red pigment were studied. The solubility of in aqueous solution was 0.084g/100 g, and the solubility of dihydromyricetin in water was 1.502g/100 g, and the solubility of dihydromyricetin in cold water and hot water was obvious. When pH is 4, the solubility of dihydromyricetin is 0.048g/100 g in water, which can achieve good results. After five times recrystallization, the purity of the dihydromyricetin was 97.8%, and the yield was 4.2%.