Studies to Investigate the Absorption and Excretion of Shea Oleine Sterols in Rat and Man

Abstract

Shea oleine (SU), an oil fraction derived from the nut of the African tree, Butyrospermum parkii, is used as a frying oil and, after hardening (SH), in margarine and toffee fat. Both SU and SH contain a high level (approximately 8%) of 4,4-dimethylsterols (4,4-DMS), mostly as esters of cinnamic acid. As part of a series of studies evaluating SU, investigations to study rat and human dietary utilization were carried out. These comprised fecal fat analysis of groups of Wistar rats and a small number (four subjects) of human volunteers. Groups of rats were administered SU in a semisynthetic diet over 3 weeks at up to 20% in the diet (approximately 10 g/kg/day). In the human study, four male volunteers consumed a single 25-g portion of SU (approximately 0.4 g/kg) and ate no other vegetable fat during the course of the study. No preferential absorption of any of the 4,4-DMS occurred in the rat or man. Apparent absorption of the most prominent sterol fraction in the unsaponifiable material, 4,4-DMS, as estimated by its disappearance from feces, was similar in both species (27% to 52% in the rat compared with 13% to 49% in human subjects). Both rats and humans showed a similar profile of dietary and fecal 4,4-DMS fraction sterol components.