Abstract

In this study we applied human large intestinal simulation model using T and AED as substrates to study the frequency of B producing trait among humans, and, the intestinal microbial fermentation conditions that favor formation of ADD - a B precursor. Bacterial 1-dehydrogenase activity which can convert T or AED into ADD is a common feature of all human fecal samples but under authentic colon conditions the formation of ADD or B is not obvious. Conditions which can "activate" formation of ADD in man are still unclear. Because the bacterial 1-dehydrogenase activity exists in the intestinal tract of every human being, verification of the "endogenous boldenone" production in doping control either by using fecal incubation or by longitudinal urinary boldenone profile is questionable and should not be used. Thus carbon isotope ratio mass spectrometry (IRMS) is the only reliable method to verify exogenous and endogenous boldenone. Furthermore, fecal contamination of urine samples and their storage at room temperature are prone to yield boldenone and its metabolites under aerobic conditions, and – because the enzymatic reaction is reversible in nature – if anaerobic conditions prevail in a sealed sampling vessel, the disappearance of xenobiotic boldenone and its metabolites is also potential. Aus dem Text