Production of luteoskyrin and isolation of a new metabolite, pibasterol, from Penicillium islandicum Sopp

Abstract

Production of luteoskyrin, a hepatotoxin synthesized by Penicillium islandicum Sopp., was studied with various fermentation methods. Best results were obtained in static fermentations on glutinous rice at 30 degrees C. The isolated yield of pure luteoskyrin was approximately 400 mg per kg of rice. Also produced were skyrin, islandicin, iridoskyrin, rubroskyrin, chrysophanol, mannitol, and erythritol. A new metabolite, which we call pibasterol, was also isolated.

Mutagenicity of islandicin and chrysophanol in the Salmonella/microsome system

“…Mycotoxins. Emodin, chrysophanol, and islandicin were isolated by methods described earlier (7,8). Commercial emodin was obtained from Aldrich Chemical Co., Milwaukee, Wis. Mutagen assay.…”

“…Emodin, chrysophanol, and islandicin are simple substituted anthraquinones which have been isolated as mold metabolites (9). Emodin, a diarrheagenic toxin (14) produced by several fungal species (7,8), has been shown to be a frame-shift mutagen in the Ames/Salmonella assay (13). In their study of twelve anthraquinone and dianthraquinone mycotoxins, Stark et al (11) evaluated the mutagenicity of islandicin and chrysophanol.…”

Plate diffusion assay as a rapid method for dosimetry of mutagens

“…PEI fractions were prepared from solid-state fernentation of rice with C. mollicellum, as described in detail by B. Kobbe (Master's thesis, Massachusetts Institute of Technology, Cambridge, 1972). PEI fractions were prepared at days 5 (0), 12 (3), and 21 (0) offermentation. PEI fractions were dissolved in dimethyl sulfoxide shortly before use, and the appropriate amounts were applied to paper disks andplaced on seededplates, as described in the text.…”

Production of cyclochlorotine and a new metabolite, simatoxin, by Penicillium islandicum Sopp

“…For example, a recent survey by the U.S. Food and Drug Administration has shown that out of 385 samples of soybeans collected from the U.S. market, 94 were contaminated with this fungus (10). A large number of toxic and nontoxic metabolites are known to be produced by P. islandicum (2,12,14,16,19). Among the potent toxins are luteoskyrin (2,3,14,16,19), cyclochlorotine (2,3,14,17,19), and islanditoxin (8,9,14).…”

“…A large number of toxic and nontoxic metabolites are known to be produced by P. islandicum (2,12,14,16,19). Among the potent toxins are luteoskyrin (2,3,14,16,19), cyclochlorotine (2,3,14,17,19), and islanditoxin (8,9,14). We have recently described the microbial production and isoaltion of luteoskyrin and a new metabolite, pibasterol (2).…”