Patent GB-796982-A (GB)
Title: An antifungal antibiotic designated ayfactin
IPC: C07G11/00
Filed: 1956-07-17
Abstract: <PICT:0796982/IV (b)/1> An antifungal antibiotic Ayfactin is produced by the submerged aerobic fermentation of a streptomycete capable of producing tetracycline and/or chlortetracycline, removing the tetracycline and/or chlortetracyline from the fermentation broth with aqueous acid and subsequently separating the mycelium from the aqueous antibiotic containing phase and recovering Ayfactin from the mycelium.  The tetracycline and chlortetracycline are removed by acidifying the broth to e.g. pH 2.0, in order to dissolve these antibiotics and then collecting the mycelium by filtration.  The mycelium is adjusted to pH 9.0 to 10.0 with e.g. NH4OH and is then extracted with an organic solvent capable of dissolving at least 2.0 g./l. of Ayfactin, e.g. n-butanol.  The solvent extract is adjusted to 7.0 and concentrated to precipitate Ayfactin.  Crude Ayfactin may be purified by (a) treatment with a non-basic organic solvent such as methyl isobutyl ketone to remove defoaming agent, e.g. lard oil, and then with water to remove salts; (b) treatment with water and methyl isobutyl ketone, followed by filtration and extraction of the filter cake with pyridine.  Ayfactin is precipitated by the addition of a non-solvent such as toluene; (c) treatment with aqueous acid, e.g. acetic acid or hydrochloric acid at pH 1.5; (d) treatment with formamide, methanol, acetone or mixtures thereof to remove impurities.  Ayfactin may be further purified by dissolving in dimethyl formamide, pyridine, morpholine or piperidine, filtering and adding a non-solvent such as toluene, aliphatic hydrocarbons or isopropyl alcohol.  Ayfactin has little or no activity against bacteria but has antifungal activity especially against Candida albicass; it contains only the elements carbon, hydrogen, nitrogen and oxygen in the following amounts: 6=64.9 per cent, H=7.7 per cent, N=3.0 per cent and O=24.4 per cent; it has a solubility in water at pH 7.0 of less than 100 mcg./ml. and is soluble in n-butanol, dimethylformamide, pyridine, morpholine and piperidine, it exhibits the following peaks of absorption and transmission of ultra-violet light when dissolved in pyridine at a concentration of 0.01 mgm./ml.: maxima (minima) 410 (400), 388 (376), 366 (354), 348 (336) and 330 mm ; it has infra-red absorption maxima at 3.1, 3.5, 5.9, 6.2 (shoulder), 6.3, 7.2-7.3, 8.55, 9.4, 10.0-10.1, 11.85 and 13.0 to 13.2.  It is distinquished from trichomycin, ascosin, candicidin and candidin. Ayfactin is used in the treatment of fungal diseases in man, animals and plants (see Group VI).ALSO:Pharmaceutical preparations for the treatment of fungal infections in humans and animals comprise the antibiotic ayfactin (see Group IV (b)) and a pharmaceutical carrier.  The compositions may take the form of tablets, effervescent tablets, powders, granules, capsules, suspensions in edible oils, injections, e.g. solution in dimethyl acetamide, suspension in oil or water containing a suspending agent such as carboxymethyl cellulose, and lotions or ointments for topical application. Solid diluents may be starch, lactose, talc, stearic acid, magnesium stearate and gums.  The dosage is 1 to 500, and preferably 10 to 20, mgms of ayfactin.  Ayfactin may be combined with one or more broad spectrum antibiotics such as tetracycline, chlortetracycline, oxytetracycline and chloramphenical.  A mixture of tetracycline and ayfactin may be used in the form of a capsule, troche, suppository, ontment or lotion.  Ayfactin is effective against the plant fungus A. solani and may be used in the form of a spray or in admixture with a fertilizer.