INFLUENCE OF NANO-SELENIUM ON ENZYMES INVOLVED IN GLUTATHIONE METABOLISM IN SPINACH AND ARUGULA LEAVES

U ovom istraživanju utvrđen je utjecaj biofortifikacije špinata i rukole pomoću dva oblika selena (nanoselen i selenat) na enzime uključene u metabolizam glutationa. Oba oblika selena primjenjena su u četiri različite koncentracije u rasponu od 40 do 320 µmol Se/m3. Primjena oba oblika selena nije uzrokovala povećanje aktivnosti glutation-peroksidaze kod špinata i rukole. Tretman nižim koncentracijama selenata uzrokovao je značajan porast aktivnosti enzima glutation-reduktaze i to samo kod rukole, dok je isti učinak izostao kod špinata. Tretman nanoselenom je kod špinata uzrokovao porast aktivnosti glutation-S-transferaze i to pri nižim koncentracijama, dok je kod rukole aktivnost GST smanjena pri višim koncentracijama nanoselena. Enzimi uključeni u metabolizam glutationa uslijed tretmana selenom pokazuju različit odgovor koji ovisi o samom kemijskom obliku selena i njegovoj koncentraciji, a isto tako taj odgovor ovisi i o karakteristikama biljne vrste koja se tretira. Dobiveni rezultati predstavljaju dobru osnovu za daljnja istraživanja mehanizma antioksidativnog odgovora biljaka na tretman selenom.The influence of biofortification using two forms of selenium (nano-selenium and selenate) on enzymes involved in glutathione metabolism in spinach and arugula was investigated in this study. Both forms of selenium were applied in four different concentrations ranging from 40 to 320 µmol Se/m3. Application of both forms of selenium didn't significantly induce the glutathione peroxidase activity in spinach and arugula. Treatment with lower concentrations of selenate caused a significant increase in glutathione reductase activity only in arugula, while the same effect was absent in spinach. Nano-selenium treatment in spinach caused an increase in glutathione-Stransferase activity at lower concentrations, while in arugula its activity decreased at higher concentrations of nanoselenium. Selenium treatment induces different response of enzymes involved in glutathione metabolism depending on the chemical form of selenium and its concentration. Also this response depends on the characteristics of plant species being treated. The obtained results represent a good basis for further research of mechanism of plant antioxidative response to selenium treatment