Affiliations: Food and Health R&D Laboratories, Meiji Seika
Kaisha Ltd., Saitama, Japan | Department of Applied Life Science, Faculty of Applied
Biological Science, Gifu University, Gifu, Japan
Note: [] Address for correspondence: Midori Natsume, Food Functionality
Research Center, Food and Health R&D Laboratories, Meiji Seika Kaisha,
Ltd., 5-3-1, Chiyoda, Sakado-shi, Saitama 350-0289, Japan. Tel.: +81 492 84
7596; Fax: +81 492 84 7598; E-mail: midori_natsume@meiji.co.jp
Abstract: Cocoa powder is rich in polyphenols, such as catechins and
oligomeric procyanidins, and has a hypocholesterolemic effect in humans. This
study evaluated the principal active components and potential mechanism(s) for
the hypocholesterolemic effect of polyphenolic substances from cocoa powder in
rats. Male Wistar rats were fed a 1% high-cholesterol diet (HC) or a
high-cholesterol diet containing 1% polyphenol extract from cocoa powder
(PE) or a mixture of 0.024% catechin and 0.058% epicatechin (CE) for 4
weeks. We also examined the effects of these polyphenolic substances on
micellar cholesterol solubility in vitro. The PE group had significantly
lower plasma cholesterol concentrations, and had significantly greater fecal
cholesterol and total bile acids excretion than the HC group. The CE group diet
did not influence plasma cholesterol concentrations, or fecal cholesterol or
total bile acids excretion. Micellar solubility of cholesterol in vitro
was significantly lower for procyanidin B2 (dimer), B5 (dimer), C1 (trimer) and
A2 (tetramer), which are the main components of polyphenol extract from cocoa
powder, compared to catechin and epicatechin. These results suggest that
oligomeric procyanidins from cocoa powder are the principal active components
responsible for the hypocholesterolemic effect, and inhibit the intestinal
absorption of cholesterol and bile acids through the decrease in micellar
cholesterol solubility.
Keywords: Cholesterol, sterol, total bile acids, procyanidins, micellar solubility, rats
Journal: BioFactors, vol. 33, no. 3, pp. 211-223, 2008
