In addition to the natural bilirubin iX-α, it also contains the III{α and XIII{α isomers. The two vinyls on the pyrrole ring of IX{α are in the medial and lateral position respectively, and under acidic conditions, two vinyls in the lateral position of the isomer III{α or in the medial position of the isomer XIII{α. The degree of isomerization varies with the type, concentration and operation of acids used for acidification in the production process. This product is mainly derived from a series of catabolic reduction products of heme in hemoglobin after the disintegration of aging red blood cells. It is golden yellow or dark reddish brown monoclinic crystal, odorless and tasteless. Dissolved in benzene, chloroform, carbon disulfide and other organic solvents; It can also be dissolved in a mixture of hot ethanol and chloroform. Sodium salts are soluble in water, but calcium salts, magnesium salts and barium salts are insoluble in water. The dry solid is more stable. Chloroform solution in the dark is also more stable; It is unstable in lye (such as 0.1mmol/L sodium hydroxide) or in the presence of trivalent iron ions and is quickly oxidized to biliverdin, which can be reduced to bilirubin by in vitro chemical reaction or biliverdin reductase. Bilirubin can bind to glycine, alanine or histidine. Bilirubin is a strong endogenous antioxidant at normal serum concentrations. The molecular structure of bilirubin can be ketone type and alcohol type, because bilirubin presents a specific curly structure, so that the hydrophobicity increases, can enter the inside of the lipid molecule. Bilirubin has an extended conjugated double bond system and active hydrogen atoms that prevent oxidation. Experiments have shown that bilirubin can inhibit the oxidative modification of LDL(low density lipoprotein in blood) to a certain extent in vitro, which can inhibit and alleviate the formation of atherosclerosis caused by LDL oxidative modification, so as to ultimately achieve the purpose of prevention and treatment of coronary heart disease.

Application:

A major component of heme breakdown, the principal pigment of bile, acting as an antioxidant and potent scavenger of hydrogen peroxide, protecting cell membrane lipids from oxidation of these active groups. It is generally used in biochemical research, analytical chemistry and synthesis of bezoar. It can also be used as an antioxidant to protect membrane phospholipids from oxidation by hydrogen peroxide free radicals, even at nanomolar concentrations to protect neurons from oxidative damage. It is also used for the determination of artificial bovis bilirubin. Bilirubin has many pharmacological effects and is the main raw material for the manufacture of artificial bezoar. Pharmacological experiments show that it has a good inhibitory effect on W256 tumor, and its inactivation rate and inhibitory index against Japanese encephalitis virus are 1 ~ 1.5 times higher than that of deoxycholic acid and cholic acid. It is also an effective liver disease treatment drugs, without destroying liver tissue, has the effect of proliferating new cells, can treat serum hepatitis, cirrhosis and other diseases, in addition, bilirubin has sedation, panic, antipyretic, antihypertensive. Promote red blood cell regeneration and other functions.