Frederick Kavanagh

Production of Hydrocyanic Acid by Cultures of a Basidiomycete

In the course of investigations on the production of antibacterial substances by Basidiomycetes, an unidentified fungus (B841) from white cedar 2 was grown on a liquid medium in 2800 ml. Fernbach flasks in a large cabinet maintained at 25° C. It was observed that Penicillium fiuniculosum grew unsatisfactorily in this cabinet on agar slopes in test tubes (FIG. 1). Investigation demonstrated that the poor growth of the Penicilliuml was caused by a volatile toxic substance produced by the B841 fungus. The toxic substance is believed to be HCN. Although HCN was first reported in Marasmius oreades by v. Losecke in 1871 (5) and has since been demonstrated in the sporophores of a number of Basidiomycetes (1, 2, 3, 4, 6), the production by fungous mycelium in culture of sufficient amounts to interfere with the growth of neighboring cultures of other organisms has not been reported. The cabinet-7 feet high, 6 feet wide and 2 feet deep-contained 7 shelves with 48 Fernbach flasks each inoculated with fungus B841 and distributed as follows: 16 on the first shelf, 6 on the second, 3 on the third, and 23 on the fourth. Each Fernbach contained 1 liter of a corn steep medium (7). The dry weight of the mycelium of fungus B841 in a Fernbach flask was approximately 3.5 g. and the surface area about 255 sq. cm. The cultures of the Penicillium were incubated on the fourth shelf. The doors of the cabinet were not hermetically sealed and were, as a rule, opened once or twice each day of the week except Saturday and Sunday. Under these circumstances, the accumulation of sufficient HCN