Bile is not always green it's color can be dark green to greenish yellow which is due to bile pigments . Bilirubin and biliverdin are two bile pigments. Bilirubin which is responsible for the yellow color is oxidized form of biliverdin which is responsible for green color. read more
The biliverdin pigment can cause vomit to appear in a range of colors from bright yellow to dark green, depending on how much bile is being regurgitated. Biliverdin is also the cause of the greenish color that can be seen in some bruises on the skin. read more
Bile or gall is a dark green to yellowish brown fluid, produced by the liver of most vertebrates, that aids the digestion of lipids in the small intestine. In humans, bile is produced continuously by the liver (liver bile), and stored and concentrated in the gallbladder. read more