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n. A yellowish-white, crystalline purine base, C5H4N4O2, that is a precursor of uric acid and is found in blood, urine, muscle tissue, and certain plants.

n. Any of several derivatives of this compound.

n. Any of a group of alkaloids, that include caffeine, theophylline, and theobromine as well as the parent compound, a precursor of uric acid found in many organs of the body.

A type of purine obtainable as a white microcrystalline powder, C5H4O2N4, present in muscle tissue, in the liver, spleen, pancreas, and other organs, and also in urine (in small quantities) and some urinary calculi, and in the juices of certain plants; -- so called because it leaves a yellow residue when evaporated to dryness with nitric acid. It is also present in guano. Xanthine is closely related to uric acid.

n. crystalline oxidation product of the metabolism of nucleoproteins; precursor of uric acid; found in many organs and in urine

"Milk fat contains an enzyme called xanthine oxidase (XO), some of which survives the pasteurization process and, thanks to homogenization, is now able to pass through the gut wall into the bloodstream intact where it creates havoc by attacking plasmalogen within artery walls."

xanthin   

organic compound   

xanthine oxidase   

cytochrome    catechol    cytosine    sulfite    pyruvate