| 摘要 |
1,212,294. Compositions containing cycloserine and O-carbamyl-D-serine. COMMERCIAL SOLVENTS CORP. 28 May, 1969 [10 June, 1968], No. 27062/69. Heading C2A. An antibiotic composition containing cycloserine and O-carbamyl-D-serine is prepared from a fermentation beer containing these antibiotics by (a) adding a protein to the beer in a proportion of 1À2 to 2À4 gms./lb. of beer; (b) adjusting the pH to 8À2-8À8 with Ca(OH) 2 or CaO; (c) concentrating the beer at subatmospheric pressure and at up to about 60‹ C., recovering a mixture containing the antibiotics and the protein from the concentrate. The beer may be obtained by aerobic cultivation of Streptomyces orchidaceous in aqueous nutrient medium. The protein, which is for stabilizing the cycloserine during concentration and drying, may be casein, soya protein, zein, gelatin, albumin (e.g. egg-white) or animal blood plasma. The pH adjustment may be made by adding just sufficient Ca(OH) 2 or CaO, or preferably by adding an excess thereof to pH 11À2-11À8 and then adjusting to pH 8À2-8À8 with an acid such as hydrochloric, sulphuric, phosphoric, acetic, propionic or butyric acid After concentrating, the whole or filtered beer is spray- or drum-dried to give the required composition. The composition may be added to animal feedstuff as a growth-promoting agent. |
