Chlorogenic Acid Is Absorbed in Its Intact Form in the Stomach of Rats

The bioavailability of chlorogenic acid, a major polyphenol of the human diet that is particularly abundant in coffee and various fruits, was explored in rats. To identify the form under which it is absorbed through the gut mucosa and the site of absorption along the gastrointestinal tract, rats were fed a diet supplemented with chlorogenic acid (0.25%, wt:wt). Chlorogenic acid and its metabolites were estimated in the stomach, small intestine and cecal contents as well as in bladder urine and plasma by HPLC with coulometric detection at several time points (1.5, 3, 4.5, and 7 h) after the beginning of the meal. Minor hydrolysis of chlorogenic acid (