Title: Induction of Fluorescence from Tremorgenic Mycotoxins Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 13, 2009
Publication Date: November 9, 2009
Citation: Maragos, C.M. 2009. Induction of Fluorescence from Tremorgenic Mycotoxins. Meeting [abstract]. 44th Annual Meeting of the UJNR Panel on Toxic Microorganisms. Abstract 12, p. 14. Technical Abstract: There are a large number of neurotoxic mycotoxins, most of which contain an indole-moiety within their structures. A subgroup of such toxins are the tremorgens, which are further divided into several smaller, structurally related groups. Tremorgens have been associated with toxic occurrences in cattle, horses, sheep, and dogs. The associated diseases are sometimes termed ‘staggers’ because of the motion demonstrated by afflicted animals. Among the tremorgens are the penitrems (tremortins), janthitrems, lolitrems, aflatrem, paxilline, paspalines, paspalitrems, fumitremorgens, tryptoquivalines, verruculogen, and others. The tremorgens can be produced by species of Aspergillus, Penicillium, Claviceps, and Acremonium. With a few exceptions, most of the tremorgens have not been reported to possess a native fluorescence. The exceptions are the janthitrems and lolitrems. Because of the general lack of fluorescence, methods for detection of tremorgens have usually relied upon their ultraviolet (UV) absorbance. Recently we discovered that the indole-containing mycotoxin cyclopiazonic acid (CPA), which is non-fluorescent, could be rendered fluorescent in a photoreactor after exposure to UV light. This suggested the possibility that other indole-containing mycotoxins, such as the tremorgens, might be rendered fluorescent by photoreaction. Three tremorgens (penitrem A, paxilline, verruculogen) that were not previously reported to be fluorescent were rendered fluorescent by exposure to UV light in a photoreactor. The three tremorgens differed in the optimal reaction conditions for producing fluorescence. The intensity of the fluorescence was strongly influenced by the reaction environment. Penitrem A and paxilline showed the greatest fluorescence enhancement when the reaction was conducted in ethanol or 2-propanol. Verruculogen showed the greatest effect in dichloromethane. Cyclodextrins, which are known to enhance the fluorescence of several mycotoxins were also shown to enhance the fluorescence of penitrem A upon photoreaction, perhaps by forming host-guest complexes. Based upon these results, experiments were conducted which demonstrated that the three tremorgens could be detected in a post-column HPLC format. The ability to photoreact indole-containing tremorgens and detect them by fluorescence may open up new avenues for detecting these mycotoxin alone or in combination with one another.