Fullerenol changes metabolite responses differently depending on the iron status of cucumber plants.

The unique properties of carbon-based nanomaterials, including fullerenol, have attracted great interest in agricultural and environmental applications. Iron (Fe) is an essential micronutrient for major metabolic processes, for which a shortage causes chlorosis and reduces the yield of many crops cultivated worldwide. In the current study, the metabolic responses of Cucumis sativus (a Strategy I plant) to fullerenol treatments were investigated depending on the Fe status of plants. Cucumber plants were grown hydroponically, either with [+FeII (ferrous) and +FeIII (ferric)] or in Fe-free (-FeII and -FeIII) nutrient solution, with (+F) or without (-F) a fullerenol supply. Iron species-dependent effects were observed in either Fe-fed or Fe-starved plants, with alteration of metabolites involved in the metabolism of carbohydrates, amino acids, organic acids, lipophilic compounds. Metabolic perturbations triggered by fullerenol in the FeIII-treated plants were in the opposite kind from those in the FeII-treated plants. Whereas in the FeIII-fed plants, fullerenol activated the metabolisation of carbohydrates and amino acids, in the FeII-fed plants, fullerenol activated the metabolisation of lipophilic compounds and repressed the metabolisation of carbohydrates and amino acids. In FeIII-deficient plants, fullerenol stimulated the metabolism of C3 carboxylates and lipophilic compounds while repressing the metabolism of amino acids, hexoses and dicarboxylates, while in FeII-deficient plants, activations of the metabolism of amino acids and dicarboxylates and repression of sterol metabolism by fullerenol were observed. The results indicated that the valence state of Fe sources is of importance for re-programming metabolome responses in cucumber to fullerenol either in Fe-sufficient or Fe-deficient conditions. These investigations are significant for understanding fullerenol interactions and risk assessment in plants with different Fe statuses

Screening of Avena sativa cultivars for iron, zinc, manganese, protein and oil content and fatty acid composition in whole grains

The common oat (Avena sativa L.) is an excellent source of nutritional compounds. The objectives of this study were: (1) to identify oat accessions cultivated in Russia with high nutritive values of grain components, including iron (Fe), zinc (Zn), manganese (Mn), protein, oil and fatty acids, and (2) to determine how the measured components are interrelated. Fifty oat accessions from the Russian germplasm collection held at the Vavilov Institute of Plant Genetic Resources were characterized. Considerable genetic variation appeared to exist in almost all nutritional contents among genotypes grown in the same environment. Genotypic variations for seed Fe and Zn were moderate (1.9–2.7-fold), while those for Mn were relatively high (10.5-fold). A 1.8-fold variation between the lowest (10.9%) and highest (19.3%) protein content in the oat grain was found. High variation in oil content (2.7–8.1%) was found among the 50 cultivated oat accessions. Major fatty acids in oat oil were linoleic (C18:2) and oleic (C18:1) acids with higher C18:2 than C18:1 in all accessions. Oil, oleic acid, protein and Zn content show a positive correlation. The identifed oat cultivars with high nutritive values would be promising for breeding programs and for providing important nutrient sources for human consumption