The invention discloses a method for one-step conversion and extraction of oleacein from olive leaves by using NADES, and the method comprises the following steps: S1, respectively pre-treating the olive leaves and olive fruits to obtain
olive leaf powder and olive fruit pulp; s2, mixing and homogenizing the
olive leaf powder and NADES, adding the olive pulp, performing ultrasonic exhaust, introducing CO2, sealing, standing, performing enzymatic
conversion reaction, and then performing ultrasonic extraction; s3, performing cooling,
centrifugation and suction
filtration on the obtained extracting solution, and collecting supernate; and S3, separating and recovering the olacein and the NADES by adopting
macroporous resin. According to the method, high-purity oracein is converted and extracted through the NADES, the method has the advantages of being
environmentally friendly, capable of saving energy, simple, efficient, high in yield and the like, meanwhile,
recovery and cyclic utilization of the NADES are achieved, the economical efficiency and
sustainability of the preparation process are improved, and therefore the method has wide application prospects.