Aflatoxin Mj and

When feed contaminated with aflatoxins Bj and B2 is given to cows, aflatoxins Mj and M2 resulting from hydroxylation of the parent compounds may be found in milk in roughly 12 h. The transition factor, which is the ratio between the amount of ingested precursor (aflatoxin Bj) and excreted aflatoxin Mp is in the range of 100 1 to 300 1. The major part of this metabolite is excreted in the urine. Trace amounts of aflatoxin Mj also appear in milk after... 

Galvano F, Galofaro y Galvano G Occurrence and stability of aflatoxin Mj in milk and milk products A worldwide review. J Food Protect 1996 59 1079-1090. 

Roebuck and Maxuitenko, 1994). In addition, aflatoxin Mj, a metabolite of AFBi, has been found in the milk of cows fed AFBi. 

The keto-carbonyl C signal at 5c = 200.9 would only fit the aflatoxins B and Mj. In the C NMR spectrum an enol ether-C/f fragment can also be reeognised from the chemieal shift value of 5c = 145.8 and the typieal one-bond coupling constant Jch 196 Hz the proton involved appears at Sff = 6.72, as the CH COSY plot shows. The H triplet which belongs to it overlaps with a sing-... 

Aflatoxin Bj is absorbed into the blood, excreted mainly through bile, and can cross the placenta. In urine, aflatoxin Bj is excreted as aflatoxin Mj. The liver is the primary site of metabolism, with P450 CYP 3A4 and 1A2 being primarily involved in the activation to highly reactive species. Half lives in humans are short (8h or less). 

The structures of the milk toxins were determined after their isolation from sheep urine74,76 and milk72, 77. The two constituents were separated, and labelled aflatoxin Mj(/5) (less polar) and aflatoxin M2(14) (more polar). The molecular formula of aflatoxin Mj(/2) was determined as C17H1207 i.e. containing one more oxygen atom than aflatoxin Bj(i). The infrared spectrum (i 3 3425, 1760,... 

The implications of the seriousness of aflatoxicosis being caused by aflatoxin Mj(7i) and/or aflatoxin M2(14) are manifest when one considers that the widespread occurence of their metabolic precursors73) necessarily precludes the possibility of a proportionally equally widespread distribution of the perhaps harmful products in milk and milk products. This fact requires, therefore, both detection9), and control11, 12 since it has been determined that the acute toxicity of aflatoxins Mt(iJ) and M2(14) is almost equal to that of the aflatoxins Bi(i) and B2(8) respectively23-26). 

Fate of Aflatoxin Mj during Cheese Manufacture and Ripening... 

Brackett, R. E., and Marth, E. H. (1982a). Fate of aflatoxin Mj in Cheddar cheese and in process cheese spread. J. Food Prot. 45, 549-552. 

Stubblefield, R. D., and Shannon, G. M. (1974). Aflatoxin Mj Analysis in dairy products and distribution in dairy foods made from artifically contaminated milk. J. Assoc. Off. Anal. Chem. 57, 847-851. 

When taken orally, the aflatoxins are absorbed from the gut and are transported to the liver where they are metabohzed. For example, aflatoxin Bi (1) may be transformed to aflatoxin Mj (5), representing a detoxification, since aflatoxin Mi (5) is less active than aflatoxin Bi (1) (see below) (27). However, a common metabolic process is diol formation at the double bond of the furan ring. The resultant aflatoxin Bi-2,3-diol is much more toxic than aflatoxin Bi (1) itself. Accordingly, diol formation results from metabolic activation to a very toxic species (29). 

The specificity of monoclonal antibodies make it possible to develop an analytical method for a single mycotoxin, such as aflatoxin Bi in maize and groundnut meal, or aflatoxin Mj in milk and milk products. Even within chemically closely related structures such as the Fusarium trichothecenes there is very little cross-reactivity between a monoclonal raised to a single toxin such as T-2 toxin and other members of the family. Thus, a monoclonal raised against 3-acetyl-deoxynivalenol showed negligible cross-reactivity with deoxynivalenol, nivalenol, or T-2 toxin. 

The use of different sorbents for the removal of mycotoxins has been the subject of intense studies. Aflatoxins may be removed from milk, cream or peanut oil using hydrated calcium aluminosilicate clay or bentonite. These mineral materials are sometimes added directly to feed to immobilise mycotoxins in the digestive tract of livestock (reducing the transfer into the blood stream). For example, the addition of hydrated calcium aluminosilicate to the feed of dairy cows decreases excretion of aflatoxin Mj to milk by 24-44%. Experiments with the immobilisation of zearalenone have been promising. However, the question remains as to whether the use of these chemisorbents does not reduce the intake of some essential minerals (such as copper, zinc and iron) and water-soluble vitamins. 

Holzapfel et al., (1966b) isolated aflatoxins Mj (2) and M2 (4) from moldy peanuts. The structures were deduced mainly from NMR data. Lactating cows transform aflatoxin Bi into aflatoxin Mj. Parasiticol (7) is formed by strains of A. parasiticus on solid media (Stubblefield et ai, 1970) and by a yeast culture of A.Jiavus (Heathcote and Dutton, 1969). 

When aflatoxin was fed to animals, certain related toxins, aflatoxin Mi (30) and Mj (32), were isolated from the milk [267]. These toxins have also been detected among the metabolic products of Aspergillus flavus [268]. 

Unlike the findings with the experimental pig and steer FDT, analyses of M] in the freeze-dried milk of the cows on aflatoxin regimen showed relatively high concentration of Mj, as summarized in Tables 2 and 3 Although the amounts of M] (and lower amounts of... 

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