Toxigenic Penicillium Species

Abstract

The discovery of penicillin in 1929 gave impetus to a search for other Penicillium metabolites with antibiotic properties and, ultimately, to the recognition of citrinin, patulin, and griseofulvin as “toxic antibiotics” or, later, mycotoxins. In a comprehensive review of the literature on fungal metabolites, about 120 common mold species were found to be demonstrably toxic to higher animals. The majority of important toxigenic and food spoilage species are found in the subgenus Penicillium. The major source of ochratoxin A in foods is bread made from barley or wheat in which P. verrucosum has grown. It has been suggested that ochratoxin A is a causal agent of Balkan endemic nephropathy, a kidney disease with a high mortality rate in certain areas of Bulgaria, Yugoslavia, and Romania. Several tremorgenic mycotoxins are produced by Penicillium species, with the most important being the highly toxic penitrem A. Verruculogen, which is equally toxic, is not produced by species of common occurrence in foods. Secalonic acid D, the only secalonic acid produced by Penicillium species, has significant animal toxicity. Basic procedures for mycotoxin assays are sampling and subsampling, extraction and cleanup, and detection, quantification, and confirmation. The newest approach to rapid assays involves the use of antibodies developed to specific toxins. Immunoassays using either spot or minicolumn tests have been developed for several major toxins. Much more research is needed to improve detection methods, to understand the ecology of toxigenic Penicillium species, and to evaluate the significance of Penicillium toxins in human health.