Extraction and purification method and application of total xanthone in polygala plants

The invention discloses an extraction and purification method and application of total xanthone in polygala plants. The method comprises the following steps: air-drying, crushing and sieving polygala;putting the sieved polygala into a flat-bottomed flask, adding ethanol, carrying out water bath heating reflux extraction twice, filtering an extracting solution, performing merging, and carrying outreduced pressure concentration to recover ethanol to obtain an extract; weighing macroporous adsorption resin, carrying out wet column packing, taking, dissolving, loading an extract sample, carryingout dynamic adsorption twice, after completing the adsorption, performing eluting with water until eluate is not turbid, performing eluting with ethanol with a volume concentration of 30% until eluate is not turbid, finally performing eluting with ethanol with a volume concentration of 30%, collecting eluate, recovering ethanol at 60 DEG C, performing concentrating under reduced pressure, and performing drying; and fully d