Enhanced separation and purification of curcuminoids on polyamide column via noncovalent interactions

• A blend of PA-6 and PS-DVB has been prepared.
• Excellent adsorption properties was observed.
• The difference of the interactions is main mechanisms to separate curcumin, DMC, BDMC from the turmeric, respectively.

In this study, a blend of polyamide-6 and poly(styrene–divinyl benzene) (PA–PS–DVB) was prepared and used to produce high-purity individual curcuminoids such as curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcum (BDMC) from turmeric crude extracts. The effects of pH and temperature on the adsorption capacities of the curcuminoids were investigated in details. Dynamic experiments on packed columns of PA–PS–DVB resin were performed, and an optimized process for gradient elution was obtained and the obtained products were further recrystallized in isopropanol. The purities of curcumin, DMC, and BDMC increased up to 99.28%, 98.8%, and 98.2%, respectively. In conclusion, the results in this work provide a cost-effective method for large-scale production of high-purity individual curcuminoids.

Functionalization of polyamide-6 into poly(styrene–divinyl benzene) adsorption resin has been applied to separate the curcuminoids and excellent adsorption properties based on synergistic effects of hydrogen bonding and π–π conjugation were achieved. The differences of the interactions were main mechanisms to elute curcumin, DMC, and DBMC from the resin with concentration gradient of ethanol.Figure optionsDownload as PowerPoint slide