GB795289A - An antibiotic vancomycin and its production by fermentation - Google Patents

Abstract

<PICT:0795289/IV (b)/1> <PICT:0795289/IV (b)/2> A new antibiotic vancomycin is prepared by cultivating under aerobic conditions a vancomycin-producing strain of Streptomyces orientalis nov. spec. in a culture medium containing assimilable sources of carbohydrate, nitrogen and inorganic salts. Submerged cultivation is preferred, at a temperature of 25 DEG to 37 DEG C. for 1 to 6 days. Specified nitrogen sources are soybean meal, casein, peanut meal, corn steep solids or liquor, amino acids, peptones, distillers' solubles, acid hydrolysate of vegetable protein, and fermentation solubles from corn. Specified carbon sources are starch, glucose, adonitol, arabinose, xylose, trehalose, mannitol, inositol, lactose and molasses. Specified mineral salts are sodium chloride, sodium nitrate, ammonium sulphate, calcium carbonate and sodium dihydrogen phosphate. Specified micro-organisms are S. orientalis NRRL 2450, NRRL 2451 and NRRL 2452. The antibiotic is isolated from a clarified broth by adsorption, e.g. on activated carbon or iron exchange resins. In one example, a filtered broth is adjusted to pH7 and passed over Permutit DR ion exchange resin on hydroxyl cycle. After washing with water, the resin is eluted with glacial acetic acid acetone and water, the acetone removed, the pH adjusted to 7.0 and treated with activated carbon. After washing the carbon is eluted with 30 per cent aqueous acetone of pH 20. The eluate is concentrated, neutralized, concentrated, adjusted to pH 2.1 with sulphuric acid and picric acid added to precipitate vancomycin picrate. This was dissolved in methanol containing aqueous hydrochloric acid and the hydrochloride precipitated by the addition of acetone. In another example the filtered broth at pH 8.5 is adsorbed on "Amberlite" IRC50 (Registered Trade Mark) on the sodium cycle and elution is with 0.1N H2SO4 or aqueous ammonia. Further purification may be by counter-current extraction employing organic solvent-containing systems. Vancomycin is a white, amorphous substance soluble in water, insoluble in most organic solvents, stable in aqueous solution at pH 2.5 to 9, having a molecular weight of 3000-3200, contains 7.17 per cent nitrogen, and a mineral oil mull thereof has a spectral absorption maxima in the infrared region at the following wavelengths expressed in microns: 3.10, 3.41, 6.05, 6.30, 6.72, 6.84, 7.26, 7.64, 8.13, 8.50, 8.66, 8.87, 9.42, 9.76, 10.10, 10.34 and 11.24. Figs. 1 and 2 represent the chromatograms of vancomycin and other antibiotics using as developers (a) aqueous ethanol and sodium chloride buffered with sodium sulphate and sodium hydrogen sulphate; and (b) n-butanol, acetic acid and water. Vancomycin is effective against gram-positive bacteria particularly streptococci and pneumococci.ALSO:Aqueous solutions of the antibiotic vancomycin (see Group IV (b)), which may be buffered, are diluted as required for use with sterile normal saline solution or sterile glucose solution. They are effective against gram-positive bacteria such as streptococci and pneumococci.