Some Effects of Aureomycin and Penicillin on Thiamine and Riboflavin Metabolism in Growing Rats. ∗

Abstract

Summary

1. The data demonstrate that both penicillin and aureomycin supplementation increased food intakes of rats subsisting on diets deficient in either or both thiamine and riboflavin, but neither antibiotic influenced food consumption when adequate thiamine and adequate riboflavin was administered. In general, growth of test animals paralleled food consumption, with indications that antibiotic supplementation improved food utilization, particularly when thiamine intake was sub-optimum. 2. The data further indicate that the amount of thiamine accounted for was increased by feeding rats diets containing either penicillin or aureomycin, or a combination of the 2 antibiotics. However, the data show that thiamine absorption was improved in the presence of antibiotics, particularly, penicillin, as indicated by lower thiamine concentration in ceca and feces, and by higher thiamine concentration in liver and urine. 3. While the data do not exclude the possibility of riboflavin synthesis in the animal body, they do indicate that if synthesis occurred it was not influenced by the presence or absence of the antibiotics under investigation. There was evidence of increased riboflavin absorption in the presence of antibiotics as indicated by lower concentrations of vitamin in ceca and feces and a higher concentration in liver.