Roridin C

A rapid immunochemical test system (immunofiltration, flow-through test) was developed for the simultaneous detection of seven mycotoxins, namely aflatoxin B1 (AFB1), fumonisin B1 (FB1), ochratoxin A (OA), deoxynivalenol (DON), T-2 toxin (T-2), diacetoxyscirpenol (DAS), and roridin A (RoA), respectively. A reusable test device, containing seven sample wells and one control well was produced. Sample extract solutions were dropped onto each sample well and the controll well, followed by toxin-enzyme conjugate solution, wash solution and colour delevoper solution. The test results were evaluated by visual comparison of colour intensity of sample wells and control well. The detection limits in buffer solution were at 0.5 ng/ml (AFB1), 5 ng/ml (FB1), 5 ng/ml (OA), 500 ng/ml (DON), 10 ng/ml (T-2), 0.5 ng/ml (DAS), and 25 ng/ml (RoA), respectively. Employing a simple extraction procedure, artificially contaminated cereal samples (wheat, maize) were analysed, with detection limits of 10 ng/g (AFB1), 50 ng/g (FB1), 50 ng/g (OA), 3500 ng/g (DON), 100 ng/g (T-2), 5 ng/g (DAS), and 250 ng/g (RoA), respectively.

Trichothecenes (TCNs) are the mycotoxins produced by many fungal species such as Fusarium, Myrothecium, and Stachybotrys and pose a considerable health risk. Based on their characteristic functional moieties, they are divided into four categories: Type A (T-2, HT-2, diacetoxyscirpenol (DAS), harzianum A, neosolaniol (NEO) and trichodermin), Type B (deoxynivalenol (DON), nivalenol (NIV), trichothecin and fusarenon X), Type C (crotocin) and Type D (satratoxin G & H, roridin A and verrucarin A) with types A and B being the most substantial. TCNs cause growth retardation in eukaryotes, suppress seedling growth or regeneration in plants and could be a reason for animal reproductive failure. Due to the increased frequency of occurrence and widespread distribution of TCNs in food and feed, knowledge of their sources of occurrence is essential to strategise their control and management. Hence, this review provides an overview of various types and sources of TCNs, the associated biosynthetic pathways and genes responsible for production in food and feed. Further, various processing and environmental effects on TCNs production, detection techniques and management strategies are also briefly outlined.

This paper presents a case report of indoor Stachybotrys toxins in Germany. In the summer of 2000, heavy rainfall and a leakage of the gutter system of an appartement house in Munich, Germany, caused a severe water damage in one of the appartments. The appartment was at that time occupied by two of the authors (ES, EU). A wall (covered with wallpaper) in one room in particular was most strongly affected, about 6-8 m(2) of the wallpaper became very wet. Large parts of this wet wallpaper were within days infested by multiple circumscribed round, grey-black colonies (0.5-5 cm in diameter) of presumtiveStachybotrys spp.. At the same time, the air in this room became very damp and oppressive. Several persons reported burning sensations on the mucous membranes of the eye, nose, and larynx, followed by headache symptoms, as soon as a few minutes after they had entered this room. Inadvertent skin contact with one of the fungal colonies by one person resulted in burning sensations immediately, but symptoms disappeared after thorough rinsing of the skin with water. The infested room was evacuated, and samples were taken from the wet wallpaper at areas (1) in the center of the most heavy fungal colony growth, (2) several cm away from colony growth, and (3) from locations which were wet but about 1 m away from visible colony growth. The samples were extracted with methanol, the extract diluted with buffer solution and analysed by competitive enzyme immunoassay (EIA) for roridin A. Due to cross-reactivity, this EIA detects several macrocyclic trichothecenes produced byStachybotrys spp.. Heavily infected pieces of wallpaper were strongly contaminated with toxins, with maximum concentrations of 1.1 microgram per cm(2) (Roridin A equivalents). Wet but visibly not infected samples of wallpaper were negative in the EIA. Considering a EIA cross-reactivity of satratoxin H (the major Stachybotrys-toxin) of 15%, the actual maximum toxin concentration would correspond to 6 microgram of satratoxin H per cm(2). As far as we know, this is the first documented case of indoor Stachybotrys toxins in Germany. The toxin concentration by far exceeds the minimum toxin level required for skin toxicity, and was considered as unhealthy. Health authorities in Munich were informed but were unable to provide assistance, probably because awareness of the importance and the possible health risks caused by indoor mycotoxins is not yet widespread in Germany. Reporting and monitoring programs for mycotoxins in water-damaged buildings seem to be necessary to provide insight into the occurrence of similar cases as the one described here.