The invention discloses a method and an apparatus used for preparing an
olive leaf extract. The method comprises the steps that: olive leaves are subjected to ultrasonic vacuum boiling extraction by using a mixed
solvent;
vacuum pump-
filtration is carried out, such that a clarified liquid is obtained; fat-soluble impurities are removed through
petroleum ether extraction, and a lower-layer clear solution is obtained; the clear solution is subjected to rotary
evaporation until no
alcohol smell is left in the
solvent; the solution is diluted; the diluant is subjected to
macroporous resin purification; the obtained solution is subjected to standing for a period of time, such that
oleuropein and
flavonoid substances are sufficiently absorbed; the
oleuropein is eluted by using an
ethanol-water mixed
solvent with a proper concentration, and a target liquid is collected; the collected target liquid is subjected to dextrane gel purification; standing is carried out, and an
ethanol-water solution is used for eluting; a eluant containing effective components is collected; the collected eluant is subjected to rotary
evaporation until no
alcohol smell is left; and the obtained material is dried, such that the extract is obtained. The
oleuropein content of the extract reaches 85-92%, and the total
flavonoid content of the extract reaches 25-35%. The method has the advantages of simple operation, short extraction time, high efficiency, high
product recovery rate, good quality, and stable quality.