Figure 1.

Schematic representation of the integrated in vitro approach to investigate the prebiotic potential of cRG-I (carrot-derived rhamnogalacturonan-I). First, potential digestion of cRG-I by amylase/brush border enzymes was investigated (Test 1). In Test 2, short-term colonic batch incubations were used to assess the prebiotic potential on microbial metabolic activity of cRG-I compared to inulin. In Test 3, the prebiotic potential of two formulations that differed in absence (cRG-I) or presence of low molecular weight carbohydrates (cRG-I+LMWC) was assessed in both conventional luminal incubations (L) and incubations including a mucosal compartment (M). Samples were collected to evaluate the effect of the test products on microbial activity, community composition and on intestinal permeability and immunity (Test 4, Caco-2/PBMC co-culture model).