Improved manufacture of the phosphorus-containing nuclear substance of milk casein

摘要

The organic phosphorus compound contained in milk casein is obtained free from mineral phosphates by digestion in weakly alkaline solution with pancreatic ferments, precipitating the filtered liquid by means of a heavy metal salt, dissolving the precipitated heavy metal salt in alkali carbonate solution, thereby leaving the mineral phosphate, precipitating the alkali metal salt with alcohol and re-dissolving it in water, again precipitating by means of a heavy metal salt and removing the heavy metal such as by means of hydrogen sulphide, and finally precipitating the free acid with alcohol and drying. The alkali carbonate solution may, if desired, be subjected to a second digestion with pancreatic ferments prior to the precipitation by alcohol. In an example, commercial milk casein is suspended in hot water and anhydrous sodium carbonate, sodium bicarbonate, trypsin or pancreas and toluene added. The filtered liquid is precipitated with sugar of lead and basic lead acetate solution. The precipitate is dissolved in sodium carbonate until slightly alkaline to phenolphthalein and the solution separated from lead phosphate and carbonate. A second digestion with trypsin may follow, and the phosphorus compound is further purified as described above, lead again being used as the heavy metal. Copper acetate or a mercury salt may also be employed as a precipitant. The alkali metal or alkaline earth salts may be obtained by neutralization of the free acid, and the iron salt by acting on the sodium salt with a soluble iron salt. Specification 210,698 is referred to.