Fate of beta-cyclodextrin in the human intestine.

We assessed the fate of beta-cyclodextrin, which is composed of seven alpha(1-->4)-linked glucose units in ring structure, in the human gastrointestinal tract. In four healthy ileostomists, ileal effluent was collected after oral administration of beta-cyclodextrin during fasting (10 g of beta-cyclodextrin) and postprandially (10 g of beta-cyclodextrin three times daily with meals). In 10 healthy volunteers, the amount of beta-cyclodextrin passing into the colon was determined by means of the breath hydrogen technique using lactulose as a standard, and stools were collected after oral administration of beta-cyclodextrin during fasting (10 g of beta-cyclodextrin) and postprandially (10 g of beta-cyclodextrin three times daily with meals). In ileostomists, we recovered from the small intestine 91 +/- 5% and 97 +/- 10% (mean +/- SD) of beta-cyclodextrin ingested during fasting and with meals, respectively. In healthy volunteers, H2 excretion in breath after beta-cyclodextrin ingestion was low compared with excretion after lactulose, but only traces of beta-cyclodextrin were recovered in stools. We conclude that beta-cyclodextrin is poorly hydrolyzed in the human small intestine but that it is fermented by the colonic flora with apparent minimal H2 production.