Abstract
The cellular components involved in the hypocholesterolemic activity of Kluyveromyces marxianus YIT 8292 were examined in rats fed on a high-cholesterol diet. Whole cells (KM) were heated at 115 °C for 10 minutes and fractionated into water-soluble extract 1 and the insoluble residue (KM-CW). After mechanical disruption by glass beads, KM-CW was separated into the cell wall (KM-W) and water-soluble extract 2. Plasma total cholesterol was decreased by feeding KM-CW or KM-W, but was not changed by feeding extract 1 or extract 2. Feeding KM-CW and KM-W increased the fecal sterol excretion and concentration of short-chain fatty acids (SCFA) in the cecum. The hypocholesterolemic activity of KM-CW was completely abolished by the enzymatic degradation of α-mannan and β-glucan. These results suggest that α-mannan and β-glucan were the major active components of KM, and that its hypocholesterolemic activity may be attributable to the increasing fecal sterol excretion and/or production of SCFA.
