Abstract
It has been known that caffeic acid and other o-diphenol compounds accelerate in vitro the decomposition of thiamine at pH 7〜7.5. The rat feeding experiments were carried out to find the activities in vivo of these thermostable antithiamine factors. The basal diet was consisted of thiamine free casein 20%, sugar 69.6%, salad oil 5.0%, salt mixture 4.0%, vitamin mixture 1.0%, choline chloride 0.1%, and DL-methionine 0.3%. The amount of thiamine administered to each rat was 40μg/day, which was given orally with the vitamin solution. The test group was given additional caffeic acid 10 times moles of thiamine or the same amount of tannic acid, or 40〜400 μg of pyrithiamine together with the basal diet. Control and test groups were pair-fed for 34〜68 days. The body weight, urinary thiamine (on the 33rd or 26th day), liver thiamine, erythrocyte transketolase activity, and thiamine pyrophosphate effect were measured for control and test groups. The results indicated that there was no significant difference in these data between the control group and the test groups of caffeic acid and tannic acid, in contrast with the difference between the control and the pyrithiamine group.
