No abstract

DURING an examination of a sample of mouldy Italian maize our late colleague, Mr J. H. V. Charles, isolated a new species of Penicillium belonging to Thom's group "The Monoverticillata-Ramigena" [Thom, 1930]. A description of this mould, which has been named P. Charlesii, has been published elsewhere [Smith, 1933]. When grown on Czapek-Dox solution or on the medium which we have called Raulin-Thom solution [Clutterbuck et al. 1932] the culture medium becomes very strongly acid, reduces KMnO4 instantly in the cold, gives an intense orange or scarlet colour with ferric chloride, and on addition of excess of alcohol gives a voluminous sticky precipitate. In addition, if the period of incubation is sufficiently prolonged, the metabolism solution becomes definitely laevorotatory. Addition of acetone to the evaporated metabolism solution precipitated a mixture of two new polysaccharides, one of which was a polygalactose and the other a polymannose. The syrupy precipitate obtained with acetone both from Czapek-Dox solution and Raulin-Thom solution gave, on trituration with absolute alcohol and ether, an amorphous hygroscopic powder with a high content of ash consisting chiefly of phosphates. Most of this ash, however, could be removed by precipitation with alcohol. The aqueous solution of the crude product from Raulin-Thom medium was acid to litmus, with an average rotation of [oI5790 =-400, and had no action on Fehling's solution or on iodine. Its behaviour on hydrolysis suggested the presence of two polysaccharides. Treated at 1000 with 0S4N sulphuric acid the rotation changed from-40°to + 610, but on pouring the equilibrium solution into alcohol a considerable portion of a polysaccharide was precipitated. With 3N sulphuric acid, however, this precipitated portion hydrolysed readily, the rotation changing from + 500 to + 14.30, the latter value being identical with the equilibrium rotation of d-mannose. The crystalline hydrolysis product from the more labile polysaccharide was identified as d-galactose, and that from the more stable polysaccharide was identified as d-mannose. By a very tedious process of fractional precipitation with alcohol a sample of the polymannose [ac]55790+630 in water, and a sample of the polygalactose [O]570 =-840 in water were obtained, thus showing that the original product was a mixture. The crude polymannose was a white hygroscopic powder containing approximately 15 % METABOLIC PRODUCTS OF PENICILLIUM CHARLESII 95 of moisure and 10 % of ash, most of the latter being removed by precipitation from hydrochloric acid solution with alcohol. It gave a colourless acid solution in water and did not react with iodine or Fehling's solution. Hydrolysis with 3N sulphuric acid gave only mannose. On acetylation a homogeneous triacetyl compound was obtained from which the original polymannose could be regenerated with sodium hydroxide. The polygalactose was identical in appearance with the polymannose. It contained only 1-8 % of ash when crude and approximately 10 % of moisture. It was readily hydrolysed...