Ochratoxin [HRP]

The garlic contains sulfur bioactive compounds responsible for medicinal properties. The decrease of these compounds due to inadequate storage conditions reduces the beneficial properties and favors infection by microorganisms. Several studies have shown high frequency of garlic infected with Aspergillus section Nigri that potentially produce mycotoxin. Garlic samples were collected in markets of Brazil and a total of 32 samples (of 36) had the fungal infection with predominant genus Aspergillus (50.3%), Penicillium (34.7%), and Fusarium (11%). A total of 63% (649/1031) of infection with Aspergillus section Nigri, of which 60 isolates were selected for analysis of genetic variability that resulted in 4 clusters. Representatives of clusters were identified by the calmodulin gene. Isolates from cluster I were subdivided into A-I and identified as A. niger (16 isolates) and the isolates of clusters B-I, II, and III were identified as A. welwitschiae (43 isolates). Besides, an isolate of the IV-cluster was identified by A. luchuensis. Further, we used the multiplex PCR to verify genotypes of 59 isolates, and none of these had OTA production-associated genotype. Moreover, 19 A. welwitschiae and 15 A. niger were FB2 production-associated genotype. Our study is the first report to the incidence of garlic infection in Brazil and to show that A. welwitschiae causes most of these infections.

The objective was to screen 10 snake venoms for their efficacy to control growth and mycotoxin production by important mycotoxigenic fungi includingAspergillus flavus,Aspergillus westerdijkiae,Penicillium verrucosum,Fusarium graminearumandF. langsethiae. The Bioscreen C rapid assay system was used. The venoms from the Viperidae snake family delayed growth of some of the test fungi, especiallyF. graminearumandF. langsethiaeand sometimesA. flavus. Some were also able to reduce mycotoxin production. The two most potent crude snake venoms (Naja nigricollisandN. siamensis;41 and 43 fractions, respectively) were further fractionated and 83/84 of these fractions were able to reduce mycotoxin production by >90% in two of the mycotoxigenic fungi examined. This study suggests that there may be significant potential for the identification of novel fungistatic/fungicidal bioactive compounds as preservatives of raw and processed food commodities post-harvest from such snake venoms.