[Effect of dietary selenium on the activity of UDP-glucuronosyltransferases and metabolism of mycotoxin deoxynivalenol in rats]. / Vliianie urovnia selena v ratsione na aktivnost' UDP-gliukuronoziltransferaz i metabolizm mikotoksina dezoksinivalenola u krys.

The influence of selenium excess and deficiency on the activity of xenobiotic metabolizing enzymes and the metabolism of mycotoxin deoxynivalenol (DON) in rats was studied. Wistar male rats were fed for 6 weeks semi-synthetic diets containing 0.2, 1.0 or 5.0 ppm selenium. For induction of selenium deficiency the weanling rats were fed for 6 weeks diet containing < or = 0.02 ppm selenium. The activity of selenium-dependent glutathione peroxidase was reduced in the liver of selenium-deficient rats by 93% at 42 days. DON, its de-epoxy metabolite DOM-1, DON and DOM-1 glucuronides were analyzed by reverse-phase HPLC in urine and feces after the single oral dose of DON (8 mg/kg). Selenium-supplemented (5 ppm) diet increased by 2-3 times formation and elimination of DON and DOM-1 glucuronides in urine. Selenium-deficient diet decreased formation of DOM-1, but increased significantly total excretion of DON and DON glucuronides. The activity of GT1 and GT2 forms of UDP-glucuronosyltransferase, an enzyme principally responsible for glucuronidation, was two times higher in the liver of rats fed both selenium-supplemented and selenium-deficient diets.

[Fusarium toxins in the cereal crop in Russia (situation in 1993 and 1994)]. / Fuzariotoksiny v zernovykh kul'turakh v Rossii (situatsiia v 1993 i 1994 gg.).

The occurrence of deoxynivalenol (DON) and zearalenone in 495 samples of food wheat, barley and rye collected from different regions of Russia, and in 633 samples of fresh harvested wheat from Krasnodar region in 1993 and 1994 was surveyed. DON was detected in 97% of fresh harvested wheat samples in 1993, exceeding maximum tolerated level MTL) in 69% of samples analyzed. 23% of fresh harvested wheat samples were positive for DON and only in 5% of samples investigated DON concentration exceed MTL in 1994. Zearalenone was found in low concentrations in 3 of 154 wheat samples analyzed. Surveys of food wheat, barley and rye samples have shown that 23%, 7% and 3% of lots were positive for DON, respectively, in 1993. DON concentration exceed MTL in 14% of food wheat samples. The frequency of DON contamination of the 1994 food wheat samples was 6%. No mycotoxins were found in the 1994 food barley and rye samples analyzed. Almost all DON contaminated lots of food grain were collected from North Caucasus region.

[Grain contamination by deoxynivalenol in Russia]. / Problema kontaminatsii zernovykh kul'tur dezoksinivalenolom v Rossii.

Deoxynivalenol (DON) contamination of fresh harvested grain (570 samples of wheat and barley harvested in 1990-1992) and food grain crops (468 samples of wheat, rye, barley from different regions of the Russian Federation) was examined for frequency and degree. DON was detected in 70% of the fresh harvested wheat, exceeding MPC in 26% of the samples and in 67% of the stored barley samples, exceeding MTL in 14%. In 1992 100% of the harvested wheat from fusariosis natural habitat were contaminated exceeding MPC in 92%. Out of 314 samples of food wheat, 29% contained DON in quantities exceeding MTL in 14%. 11% of food barley and 8% of food rye samples contained DON within MTL. Maximum quantities of contaminated wheat were produced in the North-Caucasian regions (66% of the contaminated samples) or were imported (21%). Contaminated wheat was used most frequently in the North-Caucasian region and Central regions (56% and 30% of the contaminated samples, respectively).