| 摘要 |
1,178,783. Antibiotic K-16. KONINKLIJKE NEDERLANDSCHE GIST - EN - SPIRITUSFABRIEK N.V. 26 Jan., 1968 [27 Jan., 1967], No. 4327/68. Heading C2A. An anti-protozoal antibiotic K-16 is produced by cultivating Streptomyces rimosus C.B.S. 569.66 or C.B.S. 570.66 or a K-16 producing- mutant thereof, in an aqueous nutrient medium under aerobic conditions. The antibiotic is isolated from the clarified broth by adjusting to pH 2À0 with acid, removing impurities, adjusting to pH 10 with alkali, removing impurities and adding a water-miscible solvent such as methanol, ethanol or acetone, to precipitate the antibiotic. Preferably, a complexing agent such as the ammonium salt of ethylene diamine tetraacetic acid is added to the solution prior to the precipitation step. The crude K-16 is dissolved in water at an alkaline pH and passed through a column of amberlite IRA 402 (in OH form), which is a strongly basic ion exchange resin. The antibiotic is eluted with acid, e.g. acetic acid containing ammonium acetate. Further purification is obtained by dissolving in aqueous ammonia, treating with charcoal and adjusting to pH 3 with acid to precipitate the antibiotic. Antibiotic K-16 is a white crystalline, amphoteric solid; sparingly soluble in water but easily dissolvable in water or addition of acid or alkali; moderately to slightly soluble in dimethylsulphoxide, dimethyl-formamide, nitrobenzene, tetrahydrofuran, dioxane, pyridine, acetonitrile, acetone, methyl isobutyl ketone, methanol, ethanol, n-butanol, diethyl ether, benzene and ethyl acetate; elementary analysis C = 38À9-40À4%, H = 5À6-5À9%, N = 13À0-13À5%; empirical formula C 14 H 18 O 10 N 4 ; [α]<SP>23</SP> D = - 68À8‹ C. (1% water); U.V. (Fig. 1, not shown) maxima at 24.2 mÁ (E<SP>1%</SP> 1cm = 290) and 278 mÁ (E<SP>1%</SP> 1cm = 313); I.R. spectrum as in Fig. 2; decolorizes KMnO 4 and bromine solutions; red colour with cone. H 2 SO 4 on acid hydrolysis yields serine and aspartic acids, A pharmaceutical composition comprises the antibiotic K-16 and a carrier.
|
