Effect of Sulphadimethylpyrimidine on the Microbial Synthesis of Thiamine and Nicotinic Acid in Human Intestine

capacity to synthesize a large amount of s01I\ essential vitamins which are absorbed a.nutilized by the host animal and that bacterio~ static agents like sulphonamides can effectively inhibit this intestinal synthesis of the vitaminsWith these drugs as new tools and with improve technique of estimation, it has been shown Wf some nutrition experts and bacteriologists tha rats can synthesize some members of B-comple^' vitamins K and E in the intestine. Najar et o. ? (1943, 1944), Ellinger et al. (1944, 194%' Ellinger and Coulson (1944) and Oppel by conducting experiments on human subjec have reported that similar synthesis of thiamin?' riboflavin, nicotinic acid and biotin takes P^c also in the human intestine. They have furtne^ shown that insoluble sulphonamides as sulpha guanidine and sulphasuxidine, because of thel poor absorption through the intestine, indue maximum inhibition in the biosynthesis of *n above vitamins of the B group. Kornberg et ^ (1944) in course of their study of the bl0~ synthesis of vitamin K succeeded in producing the deficiency of this vitamin in rats by using soluble sulphonamides as sulphapyrazine, sU '