Preparation of succinylated derivatives of psyllium and their physicochemical and bile acid-binding properties

The succinyl psyllium derivatives were successfully prepared by reacting psyllium with succinic anhydride, 4-dimethylaminopyridine and tributylamine in N,N-dimethylformamide. Three succinyl psyllium derivatives with different degrees of substitution were prepared and denoted as S-Psy-L, S-Psy-M and S-Psy-H. FT-IR spectrum and 1H NMR of the succinylated psyllium showed that its monoester derivative, with succinyl groups, was formed successfully. The succinyl derivatives were also evaluated for their surface structure, gelling properties, water uptake capacities, swelling volumes, and bile acid-binding abilities in vitro. The results showed that succinylation significantly reduced the gelling properties and swelling ability of psyllium, as well as increased water uptake abilities and bile-acid binding capacities. The results of this study suggested that succinylation could be a potential approach for obtaining novel derivatives of psyllium with improved physicochemical and biological properties for application in functional foods or other consumer products.