Aflatoxins table

Pea.nuts, The proteins of peanuts are low in lysine, threonine, cystine plus methionine, and tryptophan when compared to the amino acid requirements for children but meet the requirements for adults (see Table 3). Peanut flour can be used to increase the nutritive value of cereals such as cornmeal but further improvement is noted by the addition of lysine (71). The trypsin inhibitor content of raw peanuts is about one-fifth that of raw soybeans, but this concentration is sufficient to cause hypertrophy (enlargement) of the pancreas in rats. The inhibitors of peanuts are largely inactivated by moist heat treatment (48). As for cottonseed, peanuts are prone to contamination by aflatoxin. FDA regulations limit aflatoxin levels of peanuts and meals to 100 ppb for breeding beef catde, breeding swine, or poultry 200 ppb for finishing swine 300 ppb for finishing beef catde 20 ppb for immature animals and dairy animals and 20 ppb for humans. 

Liver cancer can also be a consequence of exposure to hepatotoxic chemicals. Natural hepatocarcinogens include fungal aflatoxins. Synthetic hepato-carcinogens include nitrosoamines, certain chlorinated hydrocarbons, polychlorinated biphenyls (PCBs), chloroform, carbon tetrachloride, dimethyl-benzanthracene, and vinyl chloride.Table 5.15 lists the chemical compounds that induce liver cancer or cirrhosis in experimental animals or... 

A protocol approved by the FDA to determine the safety of low gossypol cottonseed kernels for human consumption was the basis for the second study by Reber (7 ). To prepare raw cottonseed flour, raw kernels were ground to meet Ro-tap sieve specifications of lab chow. To prepare roasted cottonseed flour, raw kernels were dry roasted at not less than 121°C for not less than 5 min. To prepare cooked cottonseed flour, raw kernels were cooked in steam until batch temperature had been at or above 121°C for 5 min. All cottonseed kernels were ground in the manner described above. The kernels contained not more than 0.037% (370 ppm) of free gossypol. They were free of Salmonella and did not contain detectable amounts of aflatoxin. The proximate analyses of the cottonseed flours are shown in Table I. 

Table III. Effect Dietary Casein Levels on the in vitro Activities of Trout Hepatic Cytochrome c Reductase, Aldrin Epoxidase, and the Conversion of Aflatoxin B- to Aflatoxicol3...

Table IV. Effect of Casein Intake Upon Conversion of Aflatoxin B] by Trout PMF to a Mutagen for Salmonella...

In particular the synthetic approach to dihydrofurans (first equation in Figure 4.23) represents a useful alternative to other syntheses of these valuable intermediates, and has been used for the preparation of substituted pyrroles [1417], aflatoxin derivatives [1418], and other natural products [1419]. The reaction of vinylcarbene complexes with dienes can lead to the formation of cycloheptadienes by a formal [3 + 4] cycloaddition [1367] (Entries 9-12, Table 4.25). High asymmetric induction (up to 98% ee [1420]) can be attained using enantiomerically pure rhodium(II) carboxylates as catalysts. This observation suggests the reaction to proceed via divinylcyclopropanes, which undergo (concerted) Cope rearrangement to yield cycloheptadienes. 

Table 6.3 Dose-response relationship for aflatoxin-induced liver tumors in rats...

Some dietary practices are thought to contribute to cancer development (Table 21.7). For example, high-temperature cooking prodnces carcinogens such as heterocyclic amines and polycychc aromatic hydrocarbons, and storing food can allow microbial carcinogens, snch as aflatoxin, to be prodnced (see Figure 21.27). 

Table L Prevention of aflatoxin contamination of cottonseed by toxigenic strains of AspergiUus flavus with a strain of the fungus which does not produce aflatoxins (Cotty, 1989. Proc. 38th Oilseed Processing Clinic, pg. 30)...

Table 31 First cycle Grubbs test calculations for aflatoxin data...

The following table includes carbon-13 shifts (in ppm) and supplemental references of selected natural products with physiological activity. Some representatives have been portrayed in figures. Examples are colchicine (Fig. 2.19), biotin (Fig. 2.52), actinomycin D (Fig. 5,13) and aflatoxin Bt (Fig. 5.17). 

In Table 2, the values of Amax and e for five aflatoxins in different solvents are given. The solutions are placed in water-tight containers, ambered or aluminium-foil covered, to protect from UV rays, and stored at 4°C. Stored, well-preserved stock solutions are stable for 1 year. Working solutions of 1 /xg/nil can be prepared weekly in benzene acetonitrile (90 10 or 97 3). 

Table 2 Wavelengths of Maximum Absorption (Amax) and Molar Coefficient of Absorption (e) of Aflatoxins...

Aflatoxins are potent carcinogenic, mutagenic and teratogenic metabolites produced by molds. The major food affected with aflatoxins are corn, peanuts, rice, cottonseeds, dried fruit and milk from ingestion (103). The US action standards established by FDA are 20 pg/Kg for foods consumed by humans and 0.5 pg/kg for milk. In the case of animal feed, the levels are from 100 to 300 pg/kg. Therefore, assays capable of detecting at these levels have to be developed, (see Table 1 (104,105)). Detection of aflatoxins entails conjugation of these small molecules with carrier proteins like bovine serum albumin to produce antibodies (20). A number of commercial kits for aflatoxins are available (see sections on kits and immunoaflinity purification). 

Table 8.2 Formation of Aflatoxin B Dihydrodiol by Liver Microsomes...

Throughout the world, there are statutory limits or advisory guidelines for the maximum levels of, especially, the aflatoxins permitted in foods and feeds (Tables... 

Table 11.6 Overview on the different CRMs for aflatoxin analysis and corresponding certified values (adapted from Boenke, 1995)...

Table 11.7 FDA guidance levels for total aflatoxins in livestock feeds and human foods...

Table 11.9 Parameters and application of ammonia/aflatoxin decontamination procedures...

There is little in the literature relative to vitamin A and colon cancer in human populations. Experimental animal studies, however, strongly suggest that vitamin A deficiency may have a role in this type of cancer. We have shown that a deficiency of vitamin A increased DMH-induced tumors and shortened the lag time for induction, compared to normally supplemented controls (72). More recently (73) we have confirmed a protective role for vitamin A in colon carcinogenesis (Table XVII). Furthermore, we have shown (74) that vitamin A deficiency can result in colon tumors in rats given aflatoxin (AFB ) which is normally a liver carcinogen (Table XVIII). The colon tumors associated with the hepatocarcinogen AFB.. appear to be a result of differences in metabolism and binding of AFB or its metabolite ) to colon DNA under conditions of vitamin A deficiency (75). 

Table XVIII. Vitamin A Tumors in Status, Rats Aflatoxin B1> and Liver and Colon...

The majority of toxicants in foods are contaminants, (e.g., microbial toxins, pesticide residues, leachable chemicals from packaging materials, food coatings, traces of heavy metals). However, the major issue in food safety is the contamination of food by mycotoxins in items such as milk and milk products, meat and meat products, and peanuts (groundnuts). Aflatoxin is highly toxic and lethal, and its carcinogenic potential is well established, even at doses as low as 0.05. ig. Mycotoxins also infect food products like rice, pulses, tapioca, and betelnuts. (Table 10-2). 

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