Method for purification of taxifolin

[0019] Example 1:

[0020] Take Douglas fir and crush it, weigh 5kg, add 30kg of 40% ethanol solution, extract twice by ultrasonic method, ultrasonic frequency is 65KHz, ultrasonic time is 20min, filter, filtrate is concentrated under reduced pressure, and the concentrated solution is applied to D-101 macroporous resin column Adsorption, 3BV water → 4BV 70% ethanol to elute the resin column, collect the eluate and concentrate it until it is alcohol-free, and then pass through 3000D hollow fiber polysulfone membrane ultrafiltration, control the inlet pressure to 0.25MPa, and the filtrate passes through 400D hollow fiber Concentrated by nanofiltration with polysulfone membrane, controlled the inlet pressure to 2.0MPa, and the concentrated solution was vacuum dried at 75°C to obtain 4.36g of Douglas fir with a content of 88.3%.

[0021] Example 2:

[0022] Take Douglas fir and crush it, weigh 2kg, add 20kg of 50% ethanol solution, extract twice by ultrasonic method, ultrasonic frequency is 40KHz, ultrasonic time is 30min, filter, filtrate is concentrated under reduced pressure, and the concentrated solution is applied to AB-8 type macroporous resin column Adsorption, 4BV water → 6BV90% ethanol to elute the resin column, collect the eluate, and concentrate it to be alcohol-free, then pass it through 6000D hollow fiber polysulfone membrane ultrafiltration, control the inlet pressure to 0.2MPa, and the filtrate passes through 500D hollow fiber Concentrated by nanofiltration with polysulfone membrane, controlled the inlet pressure to 1.0MPa, and the concentrated solution was vacuum dried at 75°C to obtain 2.16g of Douglas fir with a content of 89.4%.