Purification of bovine pancreatic glucagon as a by-product of insulin production.
A process for purifying bovine pancreatic glucagon as a by-product of insulin production is described. The glucagon-containing supernatant from the alkaline crystallization of insulin was precipitated using ammonium sulfate and isoelectric precipitation. The isoelectric precipitate containing glucagon was then purified by ion-exchange chromatography on Q-Sepharose FF, gel filtration on Sephadex G-25 and ion-exchange chromatography on S-Sepharose FF. A pilot scale test was performed with a recovery of 87.6% and a purification factor of 8.78 for the first chromatographic step, a recovery of 75.1% and a purification factor of 3.90 for the second, and a recovery of 76.2% and a purification factor of 2.36 for the last one. The overall yield was 50%, a purification factor of 80.8 was obtained and the fraction containing active glucagon (suitable for pharmaceutical preparations) was 84% pure as analyzed by HPLC.
Departamento de Bioquímica, Universidade Federal de Minas Gerais, Belo Horizonte, Brasil.
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Andrade
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Vilela
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Tunes
D000818:Animals; D002417:Cattle; D005934:Glucagon / Q000302:isolation & purification*; D007328:Insulin / Q000302:isolation & purification*; D010179:Pancreas / Q000737:chemistry*
D007328:Insulin; D005934:Glucagon