Combination of supercritical fluid elution and resin adsorption for removal of procymidone from ginseng extracts

We propose a new method of resin adsorption (RA) coupled with supercritical fluid elution (SFE) for removal of pesticide residue and recovery of ginsenosides from ginseng extracts. D-101-1 resin was selected as the proper adsorption resin, acetone- n -hexane (4 : 6, v : v) served as the modifier with the flow rate of 1.5 mL/min during supercritical CO 2 elution of procymidone at 25 MPa, 55°C for 2 h, and absolute ethanol as the modifier at a flow rate of 1 mL/min for supercritical CO 2 elution of ginsenosides at 20 MPa, 60°C and 1 h. The results showed that the content of procymidone in the final products was only 0.0089 mg/kg. Meanwhile, the recovery rate of ginsenosides reached up to 92.5%. RA-SFE procedure provides an efficient approach to remove pesticide residue traces with little loss of active ingredients. The used resin can be recycled without any additional regeneration.