[Enzyme immunoassay of the secondary metabolites of micromycetes as components of lichen substances].

The composition of low-molecular biologically active metabolites typical of microscopic fungi has been studied in blastemas of fruticose lichens of the genera Cladonia, Cetraria, Evernia, Bryoria, and Usnes. The enzyme immunoassay method showed the presence of sterigmatocystin, emodin, mycophenolic acid, citrinin, alternariol, and diacetoxyscirpenol, which occurred regularly and, in most cases, at a frequency of 55 to 100%. The highest levels of accumulation were 0.001-0.003% for emodin, 0.0002% for alternariol and citrinin, 0.0001% for sterigmatocystin and mycophenolic acid, and 0.00005% of the weight of air-dry material for diacetoxyscirpenol. Other metabolites (cyclopiazonic acid, ergot alkaloids, ochratoxin A, PR toxin, deoxynivalenol, zearalenone, and fumonisins) were detected in these lichens less frequently (sometimes only upon the expansion of the territory of sampling), and their content was no more than 0.00005%. The peculiarities of the component composition and the levels of accumulation of fungal metabolites in lichens of different taxonomic affiliation were discussed.