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A 61-year-old woman with depression developed recurring elevated itching erythematous lesions in light-exposed areas after taking St. John's Wort-extract for three years. Routine patchtesting did not reveal any relevant reactions and photopatch testing was negative. Using a systemic oral photoprovocation test with St. John's Wort, we were able to demonstrate a decrease of the MED-UVB which was reversible after withdrawal of the medication.

The investigation of susceptibility of Candida species to fluconazole was performed in microdilution to a supplemented HR-medium. The sufficient reproducibility of the test was verified using special control isolates and isolates of patients. The excellent applicability of the method in routine diagnostics was evaluated by in vitro testing of susceptibility of 279 Candida isolates from patients being colonised or suffering from endomycoses. The Candida species showed different susceptibility against fluconazole: 96% of the C. albicans isolates were sensitive, 55% of the C. glabrata isolates had a reduced sensitivity, and 26% were resistant against fluconazole (MIC25 micrograms/ml). C. krusei isolates were highly resistant (9 of 11 strains).

The influence of one-and two-sided regulated atmospheres with lower 02-and increased CO2-concentrations in comparison with air was studied on the growth and toxin-production of 4 different mycotoxin-producing molds (A. versicolor, P. expansum, P. urticae, B. nivea). Low O2-values in the atmosphere (2-0.5%) had scarely an influence on the development and toxinproduction in different nutrient media after 14 d at 25 degrees C. Only higher CO2-and lower O2-concentrations than that of the air (e.g. 40% CO2, 6% O2) reduced the sterigmatocystin-and patulin-production in nearly all cultures, whereas growth was only retarded insignificantly. Atmospheres with 90% CO2 and 10% air as well nitrogen atmospheres with 10% CO2 inhibited remarkably the growth of molds and prevented the toxin-production of nearly all strains. In pure N2-atmospheres most of the A. versicolor strains exhibited growth with toxic mycelia whereas only minimum growth of the patulin-producing species without any patulin synthesis had been observed.

A total of 142 samples of vegetable foods was examined for the occurrence of sterigmatocystin. The samples examined were fruits and vegetables which had spontaneously gone mouldy or begun to rot under natural conditions on the one hand, and organoleptically impeccable fruit juices and maize specimens on the other hand. The samples were taken at the manufacturing plant or procured on the market in the framework of operative controls. Sterigmatocystin was detected in none of the samples under investigation. From this it may be concluded that the risk of its occurrence in vegetable foods is not very great in our country. Nevertheless, due to its cancerogenic and toxic properties, sterigmatocystin should remain included in the examination for mycotoxins in the framework of food control.

To test the suitability of fruit as an appropriate substrate for the formation of the mycotoxin sterigmatocystin, various fruit products were inoculated with a suspension of spores of a toxicogenic strain of Aspergillus versicolor. After incubation at 22 degrees C for 14 days, the fruits and juices overgrown with mould were homogenized with ethyl acetate and subjected to thinlayer chromatography. Sterigmatocystin had been formed on most products, the largest amounts being found in gooseberry preserves (9.4 microgram/g) and in grapes (10 microgram/g). The experiments show that fruit is generally suited as a substrate for the formation of sterigmatocystin; consequently, the latter is likely to occur in the presence of Aspergillus versicolor.