Separation of anthocyanins from roselle by macroporous resins

The absorption and desorption properties of total roselle anthocyanins on macroporous resins including NAK-9,X- 5,AB- 8,DM130,DA201,Sp850 and XAD- 7 were compared. According to the results,Sp850 resin offered better absorption and desorption capacity for roselle anthocyanins than other resins,and its adsorption data at 25℃ fit the best to the Langmuir isotherm.Dynamic adsorption and desorption experiments were carried out on the Sp850 resin packed column to optimize the separation process of anthocyanins from roselle extracts. The optimum parameters for adsorption were as follows: sample p H2.0,flow rate 2BV / h,14.3mg anthocyanin / g resin;for desorption were: elution solvent 60% ethanol and flow rate 2BV / h. Based on the visible spectrum and HPLC results,the anthocyanin compositions didn't change through the separation process. After be treated with Sp850 resin,the anthocyanins content in the product was increased 7.4- fold from 5.8% to 36.8%,with a recovery yield of64.9%.