Minor mycotoxins

Barley-associated fungi are also responsible for the production of bioactive compounds called emerging or minor mycotoxins. This group includes toxins such as enniatins (ENNs) and beauvericin (BEA). Recently, the occurrence and fate of these toxins in the barley-to-beer chain have gained attention (Hu, Gastl, Linkmeyer, Hess, Rychlik, 2014 Vaclavikova et al., 2013). 

Because NIV is a minor mycotoxin in the world, information for risk assessment is very poor. Of course, European countries and Japan have recognized the threat posed by NIV to human health and have started to evaluate this risk. In the risk assessment of NIV, it is recommended to take into account the effect of co-contamination with other trichothecene mycotoxins, namely, DON. As further studies, combination toxicology studies of NIV and DON are needed. 

Compared to the preventative strategies described above, weed control is thought to have a relatively minor effect on Fusarium infection and mycotoxin levels in grain, but there are few studies available. However, it should be noted that weed density is often higher in organic farming systems and that certain weeds can act as alternative hosts for Fusarium. For example, Fusarium contamination has been detected by Meier (2003) especially on climbing... 

The Elemental Content of Human Diets and Excreta The Elemental Constituents of Soils Mycotoxins Occurrence, Distribution, and Chemical Speciation of some Minor Dissolved Constituents in Ocean Waters. 

Substantial inhibition of ribonucleic acid (RNA) synthesis (86% inhibition) by trichothecene myco-toxin was observed in human (HeLa) cells,47 but T-2 toxin had minor effects (15% inhibition) on RNA synthesis in Vero cells.46 The trichothecene myco-toxin-related inhibition of RNA synthesis is probably a secondary effect of the inhibition of protein synthesis. Scheduled DNA synthesis is strongly inhibited in various types of cells that are exposed to trichothecene mycotoxins. In mice or rats treated with trichothecene mycotoxins, DNA synthesis in all tissues studied was suppressed, although to a lesser degree than protein synthesis.49 The pattern by which DNA synthesis is inhibited by the trichothecene mycotoxins is consistent with the primary effect of these toxins on protein synthesis. In appropriate cell models, for the most part, trichothecene mycotoxins demonstrate neither mutagenic activity nor the capacity to damage DNA.50... 

Minor metab. of Aspergillus flavus, also found in the milk of cows and sheep fed toxic meal. Mycotoxin. Cryst. (MeOH) exhibiting blue-violet fluor. Mp 299 dec. [a]20 -280 (c, 0.1 in DMF). 

The potent neurotoxic mycotoxin citreoviridin (17a now termed citreoviridin A), responsiole for the epidemic-like occurrence of cardiac beri-beri in E.Asia and previously isolated from Penicillium citreoviride and related species ( f. ], 130), has now been obtained with five similar minor metabolites (citreoviridins B-F) from Aspergillus terreus. one of the commonest micro-organisms found in soil and on various grains and sugar-containing nutrients citreoviridins C and D have been formulated as (17b) and (17c), respectively. A new pyrene (IB) has been isolated from... 

These general principles will now be illustrated from secondary metabolic pathways leading to acknowledged mycotoxins. We can summarize them in the statement that under conditions which are optimal for its growth a fungus will display little or none of its potential for secondary biosynthesis, but under suboptimal conditions (and with minor genetic changes that have the same effect) the precise pattern of secondary metabolism elicited will depend both on the prior history of the culture and on its current environmental conditions. 

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