Toxins Aspergillus

Delayed action cytotoxins that inhibit the synthesis of nucleic acids. They are obtained from various molds/fungi (Aspergillus flavus, Aspergillus parasiticus). They are colorless to pale-yellow crystalline materials melting above 450°F. The "B" toxins fluoresce blue in the presence of UV light while the "G" toxins fluoresce green. They are only slightly soluble in water, but are soluble in methanol, acetone, and chloroform. Aqueous solutions are "probably stable" and "probably tolerant" to chlorine at purification concentrations. 

Odlaug, T.E. and Pflug, I.J., Clostridium botulinum growth and toxin production in tomato juice containing Aspergillus gracilis, Appl. Environ. Microbiol., 37, 496-504, 1979. 

The aflatoxins are rather unpleasant fungal toxins. At high levels they can cause severe liver damage in animals and humans, and at lower levels they are implicated in liver cancer. These toxins are produced by the fungus Aspergillus flavus, a common contaminant on nuts and grains. Aflatoxin Bi is the most commonly encountered... 

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... 

Aflatoxins, e.g., 40, comprise a family of related products that are elaborated by the fungus Aspergillus flavus and end by contaminating the food, such as peanuts, upon which the fungus grows. Several aflatoxins, notably B, and Gj, become covalently hydrated in the mammalian liver to give the true toxin 41, which is a hemiacetal. This change... 

Many parasitic fungi have been shown to produce toxins however, the toxins of Aspergillus and PeuirHHum have perhaps the greatest potency against humans. 

Several investigators have shown that toxic strains of Fusarium, Cladosporium, Penicillium, and Mucor can sporulate and grow at temperatures well below 0°C. It also has been shown that toxin formation can be associated with overwintering of grain in the field. In some varieties of barley, such as Siri and Mala, the incidence of Aspergillus and... 

Cholera toxin B subunit-biotin labeled (lyophilized powder, biotin content 0.9mol/mol protein), peroxidase-labeled IgG anti-rabbit antibody (HRP-Ab, from goat, protein content 0.8mg/ml, affinity isolated antibody), anti-cholera toxin (from rabbit, protein content 48mg/ml, purified toxin from Vibrio cholerae), biotin monoclonal anti-rabbit IgG -y-chain specific (from mouse, protein content 4.2mg/ml), glucose oxidase-biotinamidocaproyl labeled (GOX-B, from Aspergillus niger, lyophilized powder containing 40-70% protein, 137 U/mg), polyoxyeth-ylene-sorbitan monolaurate (Tween 20), bovine serum albumin (fraction... 

The most common source of aflatoxins is moldy food, particularly nuts, some cereal grains, and oil seeds. The most notorious of the aflatoxins is aflatoxin B1( for which the structural formula is shown in Figure 19.1. Produced by Aspergillus niger, it is a potent liver toxin and liver carcinogen in some species. It is metabolized in the liver to an epoxide (see Section 7.3). The product is electrophilic with a strong tendency to bond covalently to protein, DNA, and RNA. Other common aflatoxins produced by molds are those designated by the letters B2, G1( G2, and M,. 

What kinds of toxins are produced by Aspergillus flavus, Fusarium, Trichoderma, Aspergillus, and Penicilliuml Give some examples of these toxins. 

Botrytized wines, being produced from mold-affected grapes, might be expected to be contaminated with OTA. Although Botrytis itself has never been reported to produce mycotoxins, associated Penicillium and Aspergillus species might be involved in toxin production. To date, studies on botrytized wine have either not detected or found low OTA levels. 

Aflotoxin Toxins produced by common molds (e.g., Aspergillus flavus and species in different foods). 

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