[Response surface optimization of purification process for pigment from Coreopsis tinctoria by macroporous resins]

To optimize the purification process of pigments from Coreopsis tinctoria with macroporous resins by establishing second regression model with response surface methodology. The experiment showed that XDA-7 resin had the best purification effect for pigments from C. tinctoria. The optimal absorption conditions for pigments from C. tinctoria were determined as follows： concentration of pigments solution 2.7 g•L⁻¹, flow rate 6 mL•min⁻¹, pH 6. Under these conditions, the absorption rate of pigments was up to 94.16%. Optimal desorption conditions were as follows： ethanol concentration 64%, flow rate 5 mL•min⁻¹, elution dosage 4 BV. Under these conditions, pigment desorption rate was as high as 98.72%.