Study On Extraction Of Dihydromyricetin In Ampelopsis Grossedentata And Its Micro-encapsulation

Dihydromyricetin(DMY) is a kind offlavonoid, which has many prominentbiological activities, such as antioxidant,scavenging free radicals,antiinflammation,relieving cough,eliminating phlegm,analgesia,bacteriostasis,anti-hypertension,descending fat,anticarcinogenic,protect the liver, etc. it has a abroad source,especially has a high content in Ampelopsis grossedentata dry tender leaves, inwhich it can reach to more than 30%(w/w). in this paper a series of extraction ofdihydromyricetih in Ampelopsis grossedentata and its micro-encapsulation werestudied.1. extraction of dihydromyricetinFrom the data of the experiments, we came to conclusion that the optimumparameters of the ultrasonic-assisted extraction ware as followed: the temperaturewas 40℃,the ethanol concentration was 65%,the liquid -to- solid rate was 18/1,the time was 40min.Compare to heat extraction and ultrasonic-assisted extraction, when the parametersunder the range of we chose, extract dihydromyricetin from Ampelopsisgrossedentata use supercritical CO₂ extraction technology was not show good.Use active carbon adsorption and recrystallization to purify dihydromyricetin, whenthe active carbon adding dosage reach to more than 2%, the purity ofdihydromyricetin can reach to 95%.2. the acute toxicological evaluation and prevention and treatment of alcoholic liverinjury of dihydromyricetinThe effect of to acute toxicological evaluation and prevention and treatment ofalcoholic liver injury was studied. The results showed that the toxicity ofdihydromyricetin is very low, the maximum tolerance dose to mouse is 5.0g/kg, andthe dihydromyricetin has a significant protective effect on liver injury caused by alcohol.3. Micro-encapsulation of dihydromyricetin The microencapsulation technology with spray-drying was studied, the best formulafor spray-drying dihydromyricetin were as followed: dihydromyricetin and wallmaterials was 15/85, the ratio of gum arabia and maltodextrin was 70/30, thequantity of emulsifier was 0.25%.The optimum technology conditions of spray-drying obtained by experiments wereas followed: The temperature of entering wind was 190℃, the content of solids was20%, the pressure of spray jet was 2.0 kgf/cm².