GB1363622A - Immuno-suppressive agent bredinin - Google Patents

Abstract

1363622 The antibiotic bredinin TOYO JOZOKK 17 May 1973 23601/73 Heading C2A The novel immunosuppressive antibiotic bredinin, (i.e. anhydro - 4 - carbamoyl -5- hydroxy - 1 - ribofuranosylimidazolium hydroxide) having the formula is produced by aerobically cultivating Eupenicillium brefeldianum (NRRL 5734) in an aqueous nutrient medium containing assimilable sources of carbon and nitrogen and then isolating the bredinin from the culture medium. The cultivation is preferably carried out by submerged aerated deep culture at 26-30‹ C. for 40-70 hours. The antibiotic is obtained from the culture medium by filtering off the mycelium, adjusting the pH of the filtrate to pH 9 and adsorbing the antibiotic therefrom on a strongly basic anion exchange resin in the -OH form. The antibiotic is eluted with 2% aqueous acetic acid, again similarly adsorbed and eluted and the eluate then concentrated in vacuo and the oily residue is triturated with methanol and acetone to give crude bredinin as a grey powder. This product is purified by chromatography of its aqueous solution on a silica gel column, and collecting the violet-coloured fractions, which are treated with H 2 S to precipitate chelated metals, filtered and dried in vacuo. The powder is dissolved in pyridine-acetic acid buffer, the solution purified over cross-linked DEAE- dextran gel and pure bredinin is crystallized from the eluate by adding methanol. Bredinin has weak activity against tumours and Candida albicans, no antibacterial activity, and strong immunosuppressive and antiviral activity.