Metabolism of soy isoflavones by the human gut microbiota

To be active, isoflavones require their transformation by the gut microbiota into more bioavailable and active metabolites, such as S-(-)equol. However, intestinal populations involved in isoflavone metabolism and equol production are not yet well characterized. Indeed, only 25-30% of Western individuals are able to produce equol. Conceivably, these individuals might be those who benefit from the health effects of soy isoflavone intake. The aim of this work was to study the role of fecal microbial constituents in the metabolism of isoflavones. For this aim, fecal samples from menopausal women that received a soy isoflavone treatment during six months were analysed. DNA was extracted and analysed in a 454 Roche platform. Identification of beneficial microbes would lead to their application in functional foods.