CELL GROWTH PROMOTING SUBSTANCE EXTRACTED FROM BOVINE SPLEEN, EXTRACTION THEREOF AND INACTIVATION TREATMENT OF VIRUS

摘要

NEW MATERIAL:A cell growth promoting substance which is a water-soluble protein, extracted from a bovine spleen, having 41,000 estimated molecular weight as well as about 6.0-6.5 isoelectric point. USE:A hepatotonic agent, drug for gastric and duodenal ulcer, damage reparative agent and culture medium additive. PREPARATION:For example, a bovine spleen is finely cut and homogenized at a low temperature. Water or sodium chloride solution, etc., is added to allow the homogenate to stand for 6hr-a whole day and night. The homogenate is then centrifuged to separated and collect the obtained supernatant liquid. Ammonium sulfate is subsequently added to the supernatant liquid so as to provide 40% saturated concentration and centrifugation is carried out to separate and collect the resultant supernatant liquid. Ammonium sulfate is then added to the supernatant liquid so as to provide 60% saturated concentration. Formed precipitates are then purified by gel filtration and ion exchange chromatography in combination and heat-treated at 60 deg.C for 10hr to carry out inactivation of viruses and afford the aimed cell growth promoting substance.