Enzymes of fructose metabolism in human small intestine mucosa.

The enzyme activities involved in fructose metabolism were measured in human intestine mucosa. Mucosa of the following gut sections were used: duodenum, jejunum, jejunum in the region of the flexura duodenojejunalis, jejunum distal region, ileum middle region and ileum in the region of the valvula ileo coecalis. Ketohexokinase, aldolase, alcohol dehydrogenases NAD- and NADP- dependent were found in all gut sections. The activity of aldehyde dehydrogenase was low in all sections tested. Triokinase could be found only in the duodenum and jejunum region and was absent in the ileum. Glycerate kinase was not present in the human intestine mucosa.