Enrichment and antioxidant properties of flavone C-glycosides from trollflowers using macroporous resin

Orientin, vitexin and other flavone C-glycosides are functional ingredients abundant in trollflowers. In this study, an efficient method for enrichment of these ingredients from the flowers of Trollius chinensis Bunge was developed using macroporous resin. Separation characteristics of six typical macroporous resins were investigated by static adsorption/desorption and dynamic separation experiments, and HPD450 was selected as optimal one. Dynamic adsorption/desorption experiments on HPD450 columns were conducted to obtain the optimal parameters, followed by a scale-up experiment. Six fractions, TC-1-TC-3 together with their acid hydrolysates were further prepared to evaluate their antioxidant capacities by 2,2-diphenyl-1-picrylhydrazyl radical and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonate) radical cation scavenging assays. They all have notable concentration-dependent antioxidant activities, with TC-1 showing strong antioxidant capacity higher than orientin. The separation process was high-efficient, low-cost and environmental-friendly, which could afford a potential approach for industrial applications.