A-zearalenone

This total synthesis is the first of three preparations of macrocycles that will be described (epothilone A, zearalenone, and muscone). All feature cycli-zation/release strategies that involve carbon-carbon bond formation.18 These efforts illustrate how the research on supported syntheses of highly complex structures has inspired the use of creative linker strategies for attachment to a solid phase. 

Soares L.M. and Rodriguez-Amaya D.B. (1989) Survey of aflatoxins, ochratoxin A, zearalenone, and sterigmatocystin in some Brazilian foods by using multi-toxin thin-layer chromatographic method. Journal of AOAC Inti., 72, 22-26. 

Studies (Shreeve et al., 1979 Robinson et al., 1979 Prelusky et al., 1984) on the indirect contamination of milk with other mycotoxins such as ochra-toxin A, zearalenone, T-2 toxin, sterigmatocystin, and deoxynivalenone have indicated that contamination of milk with these mycotoxins does not represent a significant public health issue. 

Alimentarium, C. (2003). Code of practice for the prevention and reduction of mycotoxin contamination in cereals, including annexes on ochratoxin A, zearalenone, fumonisins and trichothecenes. CAC/RCP, 51-2003,13. 

Soleimany, R, Jinap, S., Faridah, A., and Khatib. 2012. A UPLC-Ms/Ms for simultaneous determination of aflatoxins, ochratoxin A, zearalenone, DON, fumonisins, T-2 Toxin and HT-2 toxin, in cereals. Food Control 25 647-653. 

R-Biopharm, Darmstadt, Germany Aflatoxins, ochratoxin A, zearalenone, fiimonisins, deoxynivalenol... 

The intramolecular coupling of organostannanes is applied to macrolide synthesis. In the zearalenone synthesis, no cyclization was observed between arylstannane and alkenyl iodide. However, intramolecular coupling take.s place between the alkenylstannane and aryl iodide in 706. A similar cyclization is possible by the reaction of the alkenylstannane 707 with enol triflate[579]. The coupling was applied to the preparation of the bicyclic 1,3-diene system 708[580]. 

Farmed animals tend to be subjected to compounds that can be classified more easily as drugs. In some cases, animals may encounter compounds in nature that have considerable limitations in inclusion in the diets of farmed animals. An example is the inclusion of zearalenone (Figure 1) and its derivatives in animal diets these have anabolic and oestrogenic properties " and are permitted to be used in some areas of the world but are prohibited from use in others, such as European Union countries. Thus this compound and its reduced isomers (zearalenols, zeranols) improve growth rates in animals but can cause reproductive problems, especially in pigs. Ralgro, which is a commercially prepared derivative of zearalenone, is used as an ear implant in beef cattle as a growth promoter in... 

Ochratoxin A, citrinin, penicillic acid, sterigmatocystine, zearalenone... 

After the dipped or sprayed chromatogram has been dried in a stream of cold air long-wave UV light (2 = 365 nm) reveals fluorescent yellow zones (flavonoids). Sterigmatocystine, which can be detected without derivatization on account of its red intrinsic fluorescence (detection limit 0.5 pg), also fluoresces pale yellow after being heated to 80°C [9] or 100°C [13] for 10 min on the other hand, citrinine, zearalenone and vomitoxin fluoresce blue. 

An intramolecular variant of the Stille coupling is suitable for the construction of macrocycles. An example is the ring-closing step to form a 14-membered lactone ring 8 in a synthesis of zearalenone as reported by Stille et al. ... 

An intramolecular palladium(o)-catalyzed cross-coupling of an aryl iodide with a trans vinylstannane is the penultimate maneuver in the Stille-Hegedus total synthesis of (S)-zearalenone (142) (see Scheme 38).59 In the event, exposure of compound 140 to Pd(PPh3)4 catalyst on a 20% cross-linked polystyrene support in refluxing toluene brings about the desired macrocyclization, affording the 14-membered macrolide 141 in 54% yield. Acid-induced hydrolysis of the two methoxyethoxymethyl (MEM) ethers completes the total synthesis of 142. 

Mayr U, Butsch A and Schneider S. 1992. Validation of two in vitro test systems for estrogenic activities with zearalenone, phytoestrogens and cereal extracts. Toxicology 74 135-149. 

Deoxynivalenol Nivalenol Zearalenone T-2 toxin Moniliformin Ochratoxin A Aflatoxins... 

Tanaka T, Hasegawa A, Yamamoto S, Lee U, Sugiura Y and Ueno Y (1988), Worldwide contamination of cereals by Fusarium mycotoxins nivalenol, deoxynivalenol and zearalenone , 1. Survey of 19 countries, J. Agric. Food Chem., 36, 979-983. 

Zearalenone (mycotoxin) scFv Passive immunization of animals in their feed A. thaliana (ecotype Columbia) Inducible lac No targeting signal - 58... 

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 is a white crystalline compound, which exhibits blue-green fluorescence when excited by long-wavelength UV light (360 nm) and a more intense green fluorescence when excited by short-wavelength UV light (260 nm). In methanol,... 

In fungal cultures a number of closely related metabolites are formed, but there is only limited evidence that these occur in foodstuffs, although there is experimental evidence for some transmission of zearalenone and a- and P-zearalenols into the milk of sheep, cows and pigs fed with these substances at high concentrations. Zearalenone does not degrade at high temperatures (Zinedine et al. 2007), but may... 

Because estrogenic mycotoxins usually occur at microgram per kilogram (pg/kg) levels there is special interest in analytical procedures for reliable detection of zearalenone and its metabolites between 10 and 100 pg/kg. In response to the risk of a great economic loss to the industry and the threat to human health as a result of exposure to zearalenone, several methods have been developed for the quantification of zearalenone and its metabolites in different foods, feeds, animal tissues, blood and urine. Detailed reviews have been given by Steyn et al. 1991 Betina 1993 Frisvad and Thrane 1993 Scott 1993 Steyn 1995 and Lawrence and Scott 2000. The determination of zearalenone in cereals can be divided into five steps grinding of the sample, extraction of the sample, clean-up, separation and detection. 

In this regard several sophisticated chromatographic methods, with a quantification limit down to about 0.2 ng/g, have been developed and published for the determination of zearalenone. The methods were mainly based on high-performance liquid chromatography (HPLC) with fluorescence detection (Krska 1998 Visconti and Pascale 1998 Schuhmacher et al. 1998 Tanaka et al. 2000), but HPLC with mass spectrometry detection was also used (Shirai et al. 2000 Josephs et al. 2001). 

Another method which uses capillary electrophoresis with laser-induced fluorescence detection can also be employed to detect zearalenone (Maragos and Appell 2007). In order to analyse trace amounts of zearalenone in plants, a sensitive, quick and accurate method, the enzyme-linked immunosorbent assay (ELISA) was developed by Chen et al. 1989. 

The endogenous existence of zearalenone in plants served as a spur to further studies and its identification in different species. Han and Meng (1986) found zearalenone in rape, Meng et al. (1986) in winter wheat, Li and Meng (1989) in Apium gaveoleus, Que et al. (1990) in cotton, Han and Meng (1991) in Lemna... 

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