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Achievements in the applications of chromatographic techniques in mycotoxicology are reviewed. Historically, column chromatography (CC) and paper chromatography (PC) were applied first, followed by thin-layer chromatograhy (TLC), high-performance liquid chromatography (HPLC) and gas chromatography (GC). Although PC techniques are no longer used in the analysis of mycotoxins, selected applications of PC are included to underline historical continuity. The most important achievements published from 1980 onwards are described. They include clean-up methods, TLC, CC, HPLC and GC of mycotoxins in environmental samples, foods, feeds, body fluids and in studies on biosynthesis and biotransformations of mycotoxins. Advantages and disadvantages of chromatographic techniques used in mycotoxicology are also evaluated.

Relationships between structural features and biological effects of mycotoxins are reviewed. Structure-activity relationships are characterized at the molecular, subcellular, cellular, or supracellular level. Major chemical and physicochemical factors responsible for bioactivity of mycotoxins are stressed. A variety of chemical families of mycotoxins are then discussed from the point of view of structure-activity relationships. The structurally related families comprise small lactones, macrocyclic lactones, isocoumarin derivatives, aflatoxins and related compounds trichothecenes, anthraquinones, indole-derived tremorgens and selected amino acid-derived mycotoxins such as sporidesmins and cyclosporines. Biological effects of mycotoxins include acute and chronic toxicity, antimicrobial activity, mutagenicity and genotoxicity, carcinogenicity and biochemical modes of action.

A critical review of the application of bioautography as a special detection method in paper and thin-layer chromatographic studies on antibiotics is presented. Examples are given to show various aspects of the bioautographic detection of antibacterial, antifungal, antiprotozoal, antiphage, phage-inducing, antiviral and cytotoxic substances. Documentation possibilities and the use of bioautography in quantitative analysis are also discussed.

The transport of radioactively labelled uracil into submerged mycelium of T. viride was measured by means of a membrane filtration technique. It was found to be time-dependent (up to 90 min) and concentration-dependent (up to 8 mmol l−1). Its concentration dependence was biphasic and consisted from the saturatable part (at the uracil concentration below 0.2 mmol l−1) with KM=0.08±0.02 mmol l−1 and Vmax=1.74±0.3 nmol (mg dry wt.)−1 h−1, and from the region at higher uracil concentration which showed only a weak saturatability with the substrate. The transport measured in the saturatable part of the curve was also pH- and temperature-dependent. The optimal pH was between 5.4 and 6.4 and the optimal temperature was at 37°C. The activation energy of 54 kJ mol−1 and the temperature quotient of Q10=2.1 could be calculated from the temperature dependence. The entry of uracil was in part inhibited by nucleobases and their analogues, nucleosides, nucleotides and amino acids. The inhibitors had similar inhibitory efficiency about 50% at 0.2 mmol l−1. 3,3′,4′,5-tetrachlorosalicylanilide (TCS), the uncoupling agent, significantly inhibited the uracil transport, but its inhibitory efficiency decreased upon increasing the uracil concentration. Ionophore antibiotics valinomycin and monensin also inhibited the uracil transport. Inhibitors of RNA-polymerase, rifamycin and rifampicin were without effect. The results suggest that at low uracil concentrations (below 0.2 mmol l−1), its transport is mediated by a carrier and is driven by the electrochemical potential of protons. At higher uracil concentrations, the transport may be driven by the concentration difference of uracil with the contribution of the proton-motive force. It is feasible that inhibitors of uracil transport tested exert their inhibition by the dissipation of the driving force rather than by the direct competition with the substrate-binding site.