Ochra toxin

This chemistry can be very powerful, since the amide product itself offers further possibilities for functionalization by lithiation. The synthesis of the natural product ochra-toxin A illustrates this point. Ochratoxins A 66 and B 67 (Scheme 34) are metabolites of Aspergillus ochraceus and Penicillium viridicatum whose presence in agricultural products... 

The third mechanism is peritubular extraction of peptides and proteins from postglomerular capillaries and intracellular metabolism. Experiments using iodi-nated growth hormone (125I-rGH) have demonstrated that, while reabsorption into endocytic vesicles at the proximal tubule is still the dominant route of disposition, a small percentage of the hormone may be extracted from the peritubular capillaries [79, 86]. Peritubular transport of proteins and peptides from the baso-lateral membrane has also been shown for insulin [87] and the mycotoxin ochra-toxin A [88]. 

Of the 15 spices marketed in India and screened by Saxena and Mehrotra (1989) for the mycotoxins, aflatoxin, rubratoxin, ochra-toxin A, citrinin, zearalenone and sterigmato-cystin, samples of coriander and fennel were found to contain the largest number of positive samples and mycotoxins. Other spices like cinnamon, clove, yellow mustard and Indian mustard did not contain detectable amounts of the mycotoxins tested. Aflatoxins are the most common contaminants in the majority of samples, levels being higher than the prescribed limit for human consumption. 

Magnoli, C., Violante, M., Combina, M., Palacio, G., and Dalcero, A. 2003. Mycoflora and ochra-toxin-producing strains of Aspergillus section Nigri in wine grapes in Argentina. Lett. Appl. Microbiol. 37, 179-182. 

Studies (Shreeve et al., 1979 Robinson et al., 1979 Prelusky et al., 1984) on the indirect contamination of milk with other mycotoxins such as ochra-toxin A, zearalenone, T-2 toxin, sterigmatocystin, and deoxynivalenone have indicated that contamination of milk with these mycotoxins does not represent a significant public health issue. 

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