In vitro degradation by colonic bacteria of inulinHP incorporated in Eudragit RS films

Inulin is a naturally-occurring gluco-fructan, which can resist hydrolysis and digestion in the upper gastro-intestinal tract. In the colon it is fermented by the colonic microflora. Therefore inulinHP (inulin with a high degree of polymerization) was formulated as a biodegradable colon-specific coating by suspending it in Eudragit RS films. The in vitro degradability of the prepared isolated films was studied by incubating them in a faecal degradation medium. Measurements of the pH of the degradation medium and determination of the permeability coefficients of the incubated films as a function of time, indicated that inulinHP was indeed degraded by the faecal bacteria, even when it was suspended in Eudragit RS films. Films with different amounts of incorporated inulinHP and with different plasticizers were evaluated. The isolated films could also withstand gastric and intestinal fluid.