TECHNOLOGY FOCUS - BIOLOGY - Preferred Method: The flavone is produced by: (i) providing D. morifolium (Ramat.), adding ethanol (70%), refluxing to extract twice for 2 hours each time, mixing the extract liquid, recovering ethanol such that the extracting liquid has no ethanol smell, centrifuging to obtain the supernatant and making up the volume using distilled water, where the concentration of the extracting liquid is 4.61 mg/ml (equal to 0.1 g raw medicine/1 ml); (ii) adding the obtained solution into the AB-8 large-pore resin column, where the sample solution concentration is 4.61 mg/ml (equal to 0.1 g raw medicine/g resin), adsorbing at 1 bed volume/hour (BV/h), eluting using 10 BV of distilled water to remove impurities, eluting using 4 BV/h of 50% of ethanol at a flowing speed of 2 BV/h, collecting 50% of ethanol eluting liquid, recovering the solvent and reducing the pressure to dry. In step (ii), the large-pore resin is filled into a column by a wet method, and the absorbing capacities are respectively 8.5 mg/g, 10.41 mg/g, 12.3 mg/g, 7.95 mg/g, and 11.67 mg/g, preferably 12.3 mg/g. Water and ethanol are used to elute in a gradient manner by first eluting using water, eluting respectively using 50-90% of ethanol and 50-70% of ethanol and collecting the ethanol eluent, where the eluting speeds are respectively 1 BV/h, 2 BV/h, 3 BV/h, 4 BV/h and 5 BV/h, preferably 2 BV/h. The used resin is pre-processed by dipping in 95% of ethanol for 24 hours, after fully swelling, filling the resin into a column, rinsing the column with 95% of ethanol to make the ratio of the flowing-out liquid to water equal to 1:3 and not generate a white turbid liquid and repeatedly washing with distilled water till there is no ethanol smell. The used resin is regenerated by dipping the resin for 2-4 hours in 3-5% of hydrochloric acid, sprinkling the resin layer using 3-5% of hydrochloric acid solution at 5-7 BV, washing with distilled water till neutral, dipping the resin for 2-4 hours in 3-5% of sodium hydroxide solution, sprinkling the resin layer with 3-5% of hydrochloric acid solution at 5-7 BV and washing with distilled water till the pH is 7. In step (i), the D. morifolium is extracted by solvent under reflowing conditions, where the solvent is water and/or ethanol, preferably 70% of ethanol. Preferred Components: In step (ii), the concentrations of the sample solution are respectively 4.61 mg/ml, 1.54 mg/ml, 0.92 mg/ml, 0.66 mg/ml, preferably 4.61 mg/ml, and the sample solution adsorbing speeds are respectively 1 BV/h, 2 BV/h, 3 BV/h, 4 BV/h and 5 BV/h, preferably 1 BV/h.