Metabolism of 14C-labelled sucrose esters of stearic acid in rats

Rats were dosed by oral gavage (250 mg/kg) with compounds containing sucrose esterified in four, six or eight positions with stearic acid. For each compound, rats excreted greater than 95% of the dose in the faeces. The extent of absorption and metabolism of radioactivity was inversely related to the degree of esterification. For rats dosed with sucrose esters labelled in the fatty acid moieties, the degree of absorption of radioactivity was highest for the tetraesterified compound (5.9% of the dose). At 120 hr after dosing with this derivative, the highest concentrations of radioactivity, aside from tissues of the gastrointestinal tract, were found in fat (183 μg-equivalents/g tissue), lymph nodes (117 μg-equivalents/g tissue) and the liver (88 μg-equivalents/g tissue); appreciable radioactivity appeared in the blood (3.9 μg-equivalents/g tissue) and collected lymph (5.0–7.6% of the dose). For rats dosed with esters labelled in the sucrose moiety, the amounts of radioactivity absorbed were lower than after dosing with the corresponding sucrose derivatives labelled in the fatty acid moieties; the absorbed radioactivity was greatest following administration of the tetraesterified compound (3.0%). Relatively little radioactivity was found in tissue samples collected from these rats. These results are consistent with limited hydrolysis of the sucrose esters, presumably to sucrose and fatty acids, prior to intestinal absorption.