Albidin, an antibiotic red pigment from Penicillium albidum

• Published in: Transactions of the British Mycological Society Vol. 34; no. 3; pp. 332 - 339
• Main Authors: Curtis, P.J., Hemming, H.G., Unwin, C.H.
• Format: Journal Article
• Language: English
• Published: 1951
• ISSN: 0007-1536
• DOI: 10.1016/S0007-1536(51)80060-3

Penicillium albidum Sopp grows well on all media tested and usually gives optimum antifungal titres in 4–8 days. Good titres are obtained on Czapek-Dox, Raulin-Thom and Weindling media, but not on peptone/Lemco/glucose; good titres are also obtained on a simplified medium with ammonium nitrate, potassium nitrate and ammonium tartrate nitrogen sources, but not with ammonium sulphate. When glucose concentration and depth of medium are varied, best growth per unit weight of sugar is obtained at low sugar concentrations. In general, initial pH has little effect on the activity produced. The antibiotic albidin is obtained from Raulin-Thom culture filtrates by extraction with chloroform in yields of about 8 mg./l. In aqueous solution at pH 3 albidin loses about 90 % of its activity in 24 hr. at 25° C. and is much less stable at a higher pH. It inhibits germination of a range of moulds at concentrations varying from 0·04 to 3 μg./ml., and is bacteriostatic at concentrations of the order of 25 μg./ml. Albidin prevents oxygen uptake by Saccharomyces cerevisiae at 10 −3 m, and reduces it by 82 % at 10 −4 m. A second, colourless, fungistatic substance melting at 156°C., and giving a deep green colour with ferric chloride, has been obtained. This is active against Botrytis allii at 25 μg./ml.