Selection and optimisation of macroporous resin for separation of stilbene glycoside from Polygonum multiflorum Thunb.

BACKGROUND: 2,3,5,4′‐Tetrahydroxystilbene‐2‐O‐β‐glucopyranoside (SG; a stilbene glycoside) is a major bioactive component of Polygonum multiflorum Thunb. (PM), a popular traditional Chinese herb. In this study a method was developed for the separation of SG from PM on macroporous resins. These were selected and optimised using the linear correlation coefficients of the Langmuir and Freundlich isotherms and a pseudo‐first‐order model to explain the kinetic results. Then dynamic adsorption and desorption experiments were carried out on a column packed with the chosen resin to optimise the separation process. RESULTS: HPD100 resin gave the best performance in the separation of SG from PM. The optimal parameters were a sample concentration in solution of 3.5 g mL^?1, a pH of 4.8, a flow rate of 1.5 mL min^?1 and an elution solvent of 40% (v/v) ethanol. Using this scaled‐up column, a product with a final SG content of 819 mg g^?1 and a recovery yield of 74.7% was achieved. In addition, pure acicular crystals of SG could be obtained from this product. CONCLUSION The results showed that HPD100 was the most efficient resin for the separation of SG, which may provide a scientific basis for larger‐scale stilbene glycoside production from PM and other plant extracts. Copyright © 2008 Society of Chemical Industry