Pueraria flower extract rich in isoflavones and a method and application of the same

A method of preparing a Pueraria flower extract rich in isoflavones includes: grinding dry Pueraria flowers to obtain a Pueraria flower powder; adding a first 20-50% ethanol solution to form a mixture, stirring and heating the mixture at 20-80° C. for 1-4 hours, removing the first solution, adding a second 20-50% ethanol solution, stirring and heating the mixture, removing the second solution, and combining the first solution and the second solution to obtain an extract solution; filtering the extract solution to remove solids; concentrating the extract solution under vacuum to obtain a crude extract containing 10-40% solid components; adding anhydrous ethanol solution to reach an ethanol concentration of the crude extract of 75-95%, storing the crude extract at 20-30° C. for 1-4 hours; centrifuging the crude extract at a speed of 2,000-5,000 r/min to obtain a supernatant; and concentrating and spray drying to obtain the Pueraria flower extract without any purification steps.