Bile (or gall) is a bitter, greenish-yellow alkaline fluid secreted by the liver of many vertebrates. It is stored in the gallbladder between meals and upon eating is discharged into the duodenum where it aids the process of digestion. Bile salts act to some extent as a detergent, helping to emulsifyfats, and thus aid in their absorption. Besides its digestive function, bile serves as the route of excretion for hemoglobin breakdown products (bilirubin) which give bile its colour. Bile also contains cholesterol, which occasionally accretes into lumps in the gall bladder, forming gallstones.
Bile from slaughtered animals can be mixed with soap. This mixture, applied to textiles a few hours before washing, is a traditional and rather effective method for removing various kinds of tough stains.
The human liver produces about a quart (or roughly a litre) of bile per day. Since bile increases the absorption of fats, it can help the body absorb fat-soluble vitamins: A, D, E, and K.
Yellow and black bile were two of the four vital fluids or humours of ancient and medieval medicine; for example, melancholia was believed to be caused by a bodily surplus of black bile.
Bilesalts combine with phospholipids to break down fat globules in the process of emulsification by associating its hydrophobic side with lipids and the hydrophilic side with water.
Since bile increases the absorption of fats, it is an important part of the absorption of the fat-soluble vitamins: D, E, K and A.
Yellow bile and fl bile were two of the four vital fluids or humours of ancient and medieval medicine (the other two were phlegm and blood); for example, melancholia was believed to be caused by a bodily surplus of fl bile.
Between 90 and 95% of bile acids are reabsorbed, mainly from the lower half of the small intestine, and undergo enterohepatic recirculation; small quantities occur in the stools and very little is normally excreted in the urine.
Within the intestines the primary bile acids are acted upon by bacteria and converted to the secondary bile acids, identified as deoxycholate (from cholate) and lithocholate (from chenodeoxycholate).
Two grams of ox bilesalts were administered daily to a child of five years who had a congenital deficiency of bilesalts, for a period of 11 months, with consequent improvement in fat absorption and no evidence of ill effects Lancet, 1955, p.1087.