Mangifera Indica Extract Accurately weigh 400g of mango leaf powder, add 8 times of 70% ethanol solution, soak for 1 hour, boil for reflux extraction for 2 hours, filter while hot, add 8 times of 70% ethanol solution to filter residue, continue to reflux for 2 hours, combine 2 times of filtrate, put it still to room temperature, accurately measure the volume of the extraction solution to a total of 6.86L, and concentrate it to 800mL according to the proportion of raw drug (N-Acetylneuraminic Acid): solution volume (Tribulus Terrestris Extract) =1:2 , 3000 R / min, centrifugation for 15 min to discard the precipitate. Accurately measure 800ml of D101 macroporous adsorption resin pretreated, and wet column.

Take the sample of the treated concentrated solution, the flow rate is 40min / BV, pre elute with 3bv water, elute with 5 times of 15% ethanol, recover ethanol from 15% ethanol eluent and concentrate to the end, weigh 10g of Ginkgo Biloba Extract  product, heat and dissolve with 20ml of 50% ethanol solution to make the solution supersaturated, stand, cool and filter, scrape off the filter cake, wash the sediment with 20ml of 50% ethanol solution, mix well Evenly, filter again, put the filter cake into the vacuum drying oven for drying at 60 ℃, and obtain the mango leaf extract sample.