(2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanal → Methyl (1R,2R,4S)-2-ethyl-1,2,3,4,6,11-hexahydro-2,5,7-trihydroxy-6,11-dioxo-4-((2,3,6-trideoxy-3-(dimethylamino)-alpha-L-lyxo-hexopyranosyl)oxy)-1-naphthacenecarboxylate

Beteiligte Stoffe

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When the fermentation was carried out at 28° C. with shaking using one of the suitable media at pH 6.9, i.e. 2% glucose, 2% potato starch, 2.5% "Meat", 0.1% KH2PO4, 0.1% MgSO4.7H2O, 0.0007% CuSO4.5H2O, 0.0001% FeSO4.7H2O, 0.0008% MnSO4.4H2O and 0.0002% ZnSO4.5H2O, the pH of the medium dropped to 5.25 to 5.10 in 20 hours and the growth of mycelium increased at 10 hours after inoculation. Thereafter, pH rose to 7.0 to 7.5 on 3 days and aclacinomycin A and B reached a maximum, i.e. 46 mcg./ml. of A and 23 mcg./ml. of B in the broth. In order to isolate aclacinomycin, the antibiotic may be extracted with a suitable solvent either from the cultured broth "in toto" without filtering the mycelium mass or from the mycelium and the culture liquid previously separated by filtration. Most of the antibiotics exist in the filtration cake which consists of the mycelium admixed with the diatomaceous earth. Thereafter, the filtration cake is pulped and stirred in an organic solvent for the extraction of antibiotics. Suitable solvents are alcohols such as methanol, ethanol, butanol, ketones such as acetone, methyl ethyl ketone; halogenated hydrocarbons such as chloroform, methylene chloride, benzene or aqueous solutions of organic or inorganic acids such as acetic acid, hydrochloric acid, sulfuric acid. Preferred are acetone, ethyl acetate, mixtures of organic solvents such as alcohols and water-immiscible ketones and aqueous solution of inorganic or organic acids.

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