GB754030A - Improvements relating to the production of erythromycin - Google Patents

Abstract

Erythromycin is produced by fermenting an erythromycin-producing-micro-organism in a substrate medium containing a water-soluble salt of propionic acid. Specified are the alkali metal and ammonium salts, e.g. sodium propionate; the alkaline earth and magnesium salts, e.g. calcium propionate; salts of heavy metals such as iron, cobalt and manganese and salts of non-toxic organic bases such as methylamine. The salt is employed in quantities of 0.05 to 1 per cent of the substrate medium. The pH is 6.0 to 7.5 and preferably 6.5. The temperature of fermentation is 25 DEG to 37 DEG C. and preferably 26 DEG to 30 DEG C. The medium is preferably aqueous containing carbohydrate 0.5 to 10 per cent, nitrogen source 0.5 to 5 per cent, and nutrient salts up to 1 per cent. Specified carbohydrates are starch, dextrose, sucrose, dextrin, molasses, brown sugar and maltose; nitrogen sources are corn steep, soya bean meal, distillers' solubles, casein, amino acid mixtures, peptones, brewers' yeast, peanut granules and peanut meal, nitrates and ammonium salts; nutrient salts are those furnishing sodium, potassium, calcium, phosphate and sulphate ions, together with the trace elements cobalt, magnesium, iron and manganese. A buffer such as calcium carbonate may be present. The propionic acid salt may be formed in situ by adding propionic acid to the fermentation medium and adjusting the pH with a base. Specification 708,159 is referred to.