Researchers at the University of Maryland and National Institutes of Health have identified the microbial enzyme responsible for giving urine its yellow hue. The enzyme, called bilirubin reductase, is involved in the conversion of bilirubin into urobilinogen, which gives urine its yellow color. This discovery could lead to further research into the gut microbiome’s role in conditions like jaundice and inflammatory bowel disease. The presence or absence of bilirubin reductase in individuals can have important health implications, such as infant jaundice and the formation of pigmented gallstones. The gut microbiome has also been linked to various other diseases and conditions.
https://phys.org/news/2024-01-urine-yellow-scientists-enzyme-responsible.html