 Mango leaves also have significant polyphenol content, including xanthonoids, mangiferin and gallic acid.The pigment euxanthin, known as Indian yellow, is often thought to be produced from the urine of cattle fed mango leaves; the practice is described as having been outlawed in 1908 because of malnutrition of the cattle and possible urushiol poisoning.This supposed origin of euxanthin appears to rely on a single, anecdotal source, and Indian legal records do not outlaw such a practice.