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Urolithin
Group of chemical compounds / From Wikipedia, the free encyclopedia
Urolithins are microflora metabolites of dietary ellagic acid derivatives, such as ellagitannins.[1] They are produced in the gut, and found in the urine in the form of urolithin B glucuronide after absorption of ellagitannins-containing foods, such as pomegranate.[2] During intestinal metabolism by bacteria, ellagitannins and punicalagins are converted to urolithins, which have unknown biological activity in vivo.[medical citation needed]
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Ellagitannins exhibit low bioavailability and are transformed in the gut to ellagic acid and its microbiota metabolites.[medical citation needed] Urolithins are found in plasma mostly as glucuronides at low concentrations.[3] Urolithins production is dependent on the gut microbiome enterotype. Individuals producing urolithins show a much higher abundance of the Clostridium leptum group of Firmicutes phylum than Bacteroides or Prevotella.[medical citation needed][4]