PROCESS FOR PRODUCING L-HISTIDINE BY FERMENTATION

1382866 L-Histidinebyfermentation KYOWA HAKKO KOGYO KK 14 April 1972 [14 April 1971] 17401/72 Heading C2C L-Histidine is produced by aerobically culturing an L-histidine producing micro-organism in a nutrient medium therefor and in the presence of a growth inhibiting agent for the said micro-organism. The L-histidine producing micro-organism is preferably selected from the Brevibacterium, Corynebacterium, Arthrobacter, Bacillus, Micrococcus and Nocardia genera and the culture may be effected at 25-30‹ C., at a pH of 5 to 8 and for 48 to 96 hours. Preferred growth inhibiting agents are antibiotics, e.g. penicillins and their biologically acceptable salts, e.g. penicillin G, potassium salt, streptomycin, cephalosporin, cycloserine, chloramphenicol, erythromycin, tetracyclin, bacitracin, kanamycin, spiramycin, viomycin, novobiocin and colistin; surface active agents, e.g. alkyl sulphates, alkylaryl sulphonates, alkyl phosphates, amide sulphonates, ester sulphonates, amide sulphates, amines or salts thereof, quaternary ammonium salts (e.g. pyridinium salts, picolinium salts), amphoteric agents of the betaine-type, sulphuric acid estertype or sulphonic acid type, polyoxyethylene ethers and esters, and sorbitan alkylester; HgCl 2 acrinol, resorcinol and cresol. The growth inhibiting agent is preferably present in the nutrient medium in a concentration of not more than 2,000 γ/ml (e.g. 100-2,000 γ/ml in the case of a non-ionic surface active agent). The L-histidine producing micro-organism may be subjected to a preliminary cultivation, prior to its incorporation with the growth inhibiting agent, for not more than 24 hours (e.g. at 25-35‹ C. and pH 5-8). The L-histidine may be recovered from the culture liquor, for example, by the use of chromatography or an ion exchange resin. The examples use micro-organisms selected from the Brevibacterium flavum, Corynebacterium glutamicum, Arthrobacter citreus and Bacillus megaterium species. L-Glutamic acid is a byproduct.