Ochratoxins, and particularly ochratoxin A (OTA), are toxic fungal-derived contaminants of food and other agricultural products. Growing evidence supports the degradation of OTA by chemical, enzymatic and/or microbial means as a potential approach to remove this mycotoxin from food products. In particular, hydrolysis of OTA to ochratoxin α (OTα) and phenylalanine is the presumptive product of degradation in most cases. In the current study, we employed the zebrafish (Danio rerio) embryo, as a model of vertebrate development to evaluate, the teratogenicity of OTA and OTα. These studies show that OTA is potently active in the zebrafish embryo toxicity assay (ZETA), and that toxicity is both concentration- and time-dependent with discernible and quantifiable developmental toxicity observed at nanomolar concentrations. On the other hand, OTα had no significant effect on embryo development at all concentrations tested supporting a decreased toxicity of this degradation product. Taken together, these results suggest that ZETA is a useful, and highly sensitive, tool for evaluating OTA toxicity, as well as its degradation products, toward development of effective detoxification strategies. Specifically, the results obtained with ZETA, in the present study, further demonstrate the toxicity of OTA, and support its degradation via hydrolysis to OTα as an effective means of detoxification.

A new, cyclic carbonate eudesmane-type sesquiterpene, eudesmacarbonate (1), was isolated from marine filamentous cyanobacterial mats associated with apparent ingestionrelated intoxications of captive bottlenose dolphins in the Florida Keys. Sequencing of 16S rDNA revealed that mats were composed of closely related Oscillatoriacean species including a previously undocumented species of Neolyngbya. The structure of 1 was elucidated by (+)-HRESIMS, 1D and 2D NMR, single-crystal X-ray diffraction, and vibrational circular dichroism data. Toxicity of 1 was assessed in the zebrafish embryo/larval model, and 1 was found to exhibit effects qualitatively similar to those observed for the known neurotoxin brevetoxin-2 and consistent with neurobehavioral impairment.

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Matrix-Assisted Laser Desorption/Ionization coupled with Mass Spectrometry (MALDI-MS) has become the method of choice for mass spectrometry based imaging (MSI) of lipids directly from tissue sections.[1] Molecular ion identification and localization with a 20-sensitivity can be achieved over a wide mass range (typically, 400-2 kDa).Current challenges are in the sample preparation method and matrix deposition to improve analysis reproducibility. For MALDI experiments, matrix choice is strongly dependent on the chemical class of interest. Lipids account for up to 50% of the dried weight of brain tissue sections compared to other chemical classes and are vital brain function regulators. Lipidomic analysis of brain tissues has significantly increased in relation to better understanding the role of lipids in the development of debilitating neurodege Our work focuses on the applications of MALDI-MS for direct lipid mapping in model systems as a function of a biological question (e.g., disease vs. non disease, low vs. high fatty acid diet, etc.). Comparison between positive and negative MS mode shows that molecular ion emission can be directly correlated to the surface concentration, the ionization probability and lipid classification. Two distinct lipid distributions were observed and can be attributed to the difference in the charge carriers (lipid head groups) for the different lipid classes.References: