GB588131A - Improvements in or relating to the manufacture of purified penicillin - Google Patents

Abstract

Concentrated and purified preparations of penicillin are prepared from culture fluids by extracting an aqueous solution of the penicillin with chloroform and separating the penicillin from the chloroform preferably by precipitation with a non-solvent for the penicillin such as petroleum ether. It is preferred that during the extraction the pH should be maintained between 6 and 8 by means of a buffer salt such as a phosphate monobasic and dibasic sodium phosphates being mentioned. In examples: (1) a filtered culture fluid is extracted with chloroform, the chloroform extract dried and treated with a buffer salt solution at pH 7.2. This aqueous solution is now acidified and again extracted with chloroform, and the penicillin precipitated with benzene; (2) a chloroform extract from a culture fluid is prepared as in example (1) and precipitated with petrol ether. The precipitate is taken up in benzene and extracted with phosphate buffer and worked up as in example (1); (3) a first chloroform extract is prepared as in example (1) treated with magnesium oxide which absorbs the active material, and is then acidified with sulphuric acid and re-extracted with chloroform and precipitated by benzene saturated with ammonia gas.