Zearalenone effect

In spite of the fact that contamination of cereals and grains and related products with mycotoxins causes food and feed-bome intoxications in man and livestock, zearalenone in low concentrations can be treated as a plant hormone which influences the development and yield of crop plants (Biesaga-Koscielniak 2001). This review focuses on the effect of low doses of zearalenone on the stimulation of selected physiological processes in plants important for agriculture production. 

Zearalenone was also found to be more effective than cytokinin treatment in inducing shoots in in vitro winter wheat production. Moreover, both zearalenone and cytokinins increased the activity of antioxidant enzymes in wheat callus undergoing regeneration, and it is very likely that they also stimulated the plant regeneration process (Szechynska-Hebda et al. 2007). The effectiveness of regeneration on media containing zearalenone shows the possibility of using zearalenone as an alternative hormone also to cytokinins in winter wheat callus culture. 

The effect of zearalenone on crop development may be connected to its influence on the status and functioning of the photosynthetic apparatus (Koscielniak et al. 2008). The after-effects of zearalenone on the growth of soybean and wheat plants, net photosynthesis and transpiration rates, stomatal conductance, photochemical efficiency of photosystem 2 and on final seeds yield were determined. Modifications in leaf area were more pronounced in soybean than in wheat, and this tendency increases in successive developmental phases. The net photosynthesis was stimulated during the juvenile phase and during that of the final one by about 13.6% (average) in soybean plants. Stimulation of transpiration was also observed after... 

Biesaga-KoScielniak J, Marcinska I, W dzony M, KoScielniak J (2003) Effect of zearalenone treatment in the production of wheat haploids via maize pollination system. Plant Cell Rep 21 1035-1039... 

Velluti A, Marin S, Bettucci L, Ramos AJ, Sanchis V (2000) The effect of fungal competition on colonization of maize grain by Fusarium moniliforme, F. proliferatum and F. graminearum and on fumonisin B and zearalenone formation. Int J Food Microbiol 59 59-66... 

Vianello A, Macri F (1981) Effect of zearalenone (F-2) on pea stem, maize root, and rat liver mitochondria. Planta 153 443-446... 

Even the sterically hindered 2,6-disubstituted aryl iodide 443 is carbonylated smoothly to give 445. Alkyl iodide present in the alcoholic component 444 remains intact under the carbonylation conditions. This carbonylation reaction is a key reaction in the synthesis of zearalenone (446) [216]. Optimal conditions for technical synthesis of the anthranilic acid derivative 448 from bromide 447 has been studied, and it has been found that A-acetyl protection of 447, which has a chelating effect, is important [217]. Cheaply available chlorides are rather inert [13]. The carbonylation of chloride 449 in the presence of DBU and Nal gives the amide 450 [218],... 

The adverse health effects most readily associated with mycotoxin consumption are either acute or subchronic. Chronic effects, such as carcinogenicity, have been more difficult to directly relate to mycotoxin consumption. This is in spite of the fact that various data indicate that at least 45 mycotoxins are known to be either mutagenic or carcinogenic (1). The following mycotoxins may pose an adverse human health risk in respect to carcinogenicity aflatoxin, cyclochlorotine, griseofulvin, luteoskyrin, ochratoxin, patulin, penicillic acid, sterigmatocystin, T-2 toxin, and zearalenone. 

Zearalenone F graminearum genitotoxin estrogenic effects mutagen cervical cancer, premature menarche... 

Hsia, C.C., Wu, J.L., Lu, X.Q., Li, Y.S. (1988). Natural occurrence and clastogenic effects of nivalenol, deoxynivalenol, 3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol, and zearalenone in com from a high-risk area of esophageal cancer. 

Zearalenone is an estrogenic mycotoxin that usually causes toxicity in swine that consume contaminated corn. Prepubertal swine are mostly affected. Affected females show swelling of the vulva and excessive straining, which may cause vaginal prolapses. In male animals, zearalenone will cause decreased libido. There is no effective treatment apart from withdrawing the feed containing the mycotoxin. 

Acylation of 145 with acid chloride 95 afforded ester 146 in 90% yield. Ester 146, containing all the necessary carbons at easily adjustable oxidation states, required only cyclization and minor functional group manipulations to afford the zearalenone system. As in Tsuji s previous synthesis of di-O-methyl lasiodi-plodin, macrocyclization was effected via deprotonation at the benzylic position and intramolecular alkylation to give 147 in 85% yield. Oxidative elimination of the thiophenyl group and removal of the ketal with acid afforded 127 (67%). the Merck group had previously demonstrated the ready conversion of 127 to zearalenone (119). 

Recently, much concern has been expressed about the effect of synthetic chemicals that have estrogen-like effects. We have touched on this lightly in previous chapters and will revisit it in Chapter 7. Zearalenone is an estrogenic mycotoxin produced by a number of species of Fusarium mold. It has caused a number of abnormalities in the reproductive system in animals and possi-... 

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