FORMATION OF TETRAHYDROHARMAN (1-METHYL-1,2,3,4-TETRAHYDRO-BETA-CARBOLINE) BY HELICOBACTER-PYLORI IN THE PRESENCE OF ETHANOL AND TRYPTAMINE

Helicobacter pylori contains alcohol dehydrogenase which oxidizes etha nol to acetaldehyde. In the present study, H. pylori cytosol was incub ated in a buffered media at pH 6.0 and 7.4 in the presence of ethanol and tryptamine. Under these conditions, tetrahydroharman (1-methyl-tet rahydro-beta-carboline) was produced as a condensation product of tryp tamine and acetaldehyde. At pH 6.0, 20.60 +/- 5.00% of the added trypt amine was converted to tetrahydroharman, while 27.00 +/- 4.80% (mean /- SD) was converted at pH 7.4. Similar reactions between acetaldehyde and other dietary amines seem likely. Such biogenic alkaloids, if for med in vivo, might contribute to the dysphoric effects of alcohol.