Patent Document ID: 4119618
Application ID: 05681045
Patent Flag: 1

Claim One:
1. A process for the isolation of a new biologically active polypeptide from the neural tissue of mammals which consists essentially of the sequential steps of: (a) obtaining neural tissue; (b) extracting said neural tissue by contacting with a member selected from the group consisting of dilute organic acyclic carboxylic acids and mixtures of organic acyclic carboxylic acids with lower alkyl alcohols; (c) concentrating the resultant extract by contacting with alginic acid, filtering the resultant alginic acid containing the absorbed extract, and collecting the alginic acid containing the absorbed extract on the filter; (d) eluting the alginic acid containing the absorbed extract by contacting with HCl aqueous solution and recovering the extract from the HCl solution; (e) subjecting the resultant extract to gel chromatography in a chromatographic column and recovering the active fraction; (f) subjecting the resulting active fraction from step (e) to at least two consecutive ion exchange chromatographic steps in a chromatographic column and recovering the active fraction therefrom; (g) subjecting the active fractions to countercurrent distribution; and (h) subjecting the resultant active fraction to lyophilization and recovering the active fraction containing the polypeptide.