Claviformin from Aspergillus giganteus Wehm.

THE production of a penicillin-like substance from Aspergillus giganteus has been described¹. Wilkins and Harris² noted that this mould produced a different antibiotic when grown in a different medium, namely, dextrose 4 per cent, NaNO₃ 0.1 per cent, KH₂PO₁ 0.1 per cent. When tap water was substituted for distilled water, production of the antibiotic was slower but the final yield greater. The mould was harvested after 4-8 weeks incubation. The active material was concentrated by adsorption on charcoal, extraction with amyl acetate and finally extraction with ethyl acetate. On concentrating and cooling this extract, crystals of active material were obtained the properties and appearance of which at once suggested that the antibiotic was identical with claviformin³. It had a melting point of 109° C., and no depression of the melting point was observed after mixing with a sample of claviformin.