METABOLISM AND DISPOSITION OF ERYTHRITOL AFTER ORAL-ADMINISTRATION TO RATS

The metabolism and disposition of erythritol was studied using [C-14]erythritol in rats. When [C-14]erythritol was administered orally at a dose of 0.1 g/kg body wt to male rats, only 6% of the total radioactivity was excreted as expired (CO2)-C-14 and 88% was excreted in the urine within 24 h. The excreted metabolite in the urine consisted of a single component identified as intact [C-14]erythritol. The excretion of (CO2)-C-14 and the incorporation ratios of radioactivity into tissues increased with the oral dosage. After rats were given an intravenous injection of [C-14]erythritol, approximately 1% was excreted as (CO2)-C-14 and > 94% was excreted in the urine as intact [C-14]erythritol. The excretion of (CO2)-C-14 within 24 h was increased to approximately 10% when [C-14]erythritol was administered to rats that had been adapted to erythritol by feeding a diet containing 10% erythritol for 2 wk. When [C-14]erythritol was incubated in vitro with the cecal contents from rats adapted to erythritol, > 20% was fermented to (CO2)-C-14 and 60% to short-chain fatty acids in 6 h. These results indicate that most orally administered erythritol was excreted in the urine without any degradation and that the remainder was transferred to the lower intestine and fermented by microbes.