Effect of casein-derived peptides on D-xylose absorption assessed by H-2 breath test in normal volunteers

Studies have shown a promoting effect of food on small intestinal absorptio n. Casein hydrolysate seems be more effective in increasing of D-xylose abs orption in dogs than the whole protein and lactulose. The purpose this stud y was to analyze the effect of groups of peptides derived from casein hydro lysate on the absorption of D-Xylose and intestinal transit time in normal subjects. Seven normal volunteers participated in the study. Three peptide fractions were isolated from casein enzymatic hydrolysate by means of a pre parative HPLC silica column. On separate days subjets drank test solutions containing lactulose, D-xylose, and D-xylose with one of three peptide grou ps. The hydrogen breath test was used to indirectly estimate D-xylose absor ption and orocecal transit time. Two peptide fractions when added to D-xylo se were followed by an increased absorption characterized by decreased H-2 production. A nonstatistically significant increase of orocecal transit tim e was observed with these peptides.