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Expression and activity of nitrate reductase (NR; EC 1.6.6.1) and glutamine synthetase (GS; EC 6.3.1.2) were analysed in relation to the rate of CO2 assimilation in cucumber (Cucumis sativus L.) leaves. Intact plants were exposed to different atmospheric CO2 concentrations (100, 400 and 1200 μL L−1) for 14 days. A correlation between the in vivo rates of net CO2 assimilation and the atmospheric CO2 concentrations was observed. Transpiration rate and stomatal conductance remained unaffected by CO2 levels. The exposure of the cucumber plants to rising CO2 concentrations led to a concomitant increase in the contents of starch and soluble sugars, and a decrease in the nitrate content in leaves. At very low CO2, NR and GS expression decreased, in spite of high nitrate contents, whereas at normal and elevated CO2 expression and activity were high although the nitrate content was very low. Thus, in cucumber, NR and GS expression appear to be dominated by sugar levels, rather than by nitrate contents.

Methods for chlorophenols (CPs) determination (with low limits of detection) that can be applied to real environmental samples (waters, sediments, soils, biological tissues) and food are reviewed. Special emphasis is given to sampling, storage conditions and the application of preconcentration techniques for the determination of CPs using chromatographic methods. Solid phase extraction, solid phase microextraction, stir bar sorptive extraction, liquid phase microextraction, dispersive liquid-liquid microextraction, liquid-liquid-liquid microextraction and purge and trap methods are considered. Methods for microwave and ultrasonic extraction of CPs from solid matrices are also focused.

Abstract: Enterprises need corporate data quality management (DQM) that combines business-driven and technical perspectives to respond to strategic and operational challenges that demand high-quality corporate data. Hitherto, companies have assigned ...

Hyoscyamine, anisodamine (6β-hydroxyhyoscyamine) and scopolamine are tropane alkaloids produced by plants belonging to the Solanaceae family such as Brugmansia candida. These alkaloids were traditionally used in medicine because of their anticholinergic activity. Further therapeutical properties for anisodamine were recently described renewing the interest in these alkaloids. The scaling-up of hairy root cultures is an interesting strategy for the pharmaceutical production of these compounds instead of the isolation from plants. In this work, B. candida hairy roots were cultured in a modified 1.5 L stirred tank in order to analyze an alternative production system of scopolamine and anisodamine. It was found that these cultures produced an increased biomass and alkaloids concentration compared to the processes carried out in Erlenmeyer flasks. Anisodamine was the predominant alkaloid reaching a maximum concentration of 10.05 ± 0.76 mg/g DW in modified bioreactor culture system. The results obtained in this work are potentially applicable for the rational scale-up of the process.

Cadmium (Cd) is a non-redox toxic heavy metal present in the environment and induces oxidative stress in plants. We investigated whether exogenous nitric oxide (NO) supplementation as sodium nitroprusside (SNP) has any ameliorating action against Cd-induced oxidative damage in plant roots and thus protective role against Cd toxicity. Cd treatment (50 or 250 μM) alone or in combination with 200 μM SNP was given to hydroponically grown wheat roots for a short time period of 24 h and then these were shifted to distilled water to observe changes in levels of oxidative markers (lipid peroxidation, H2O2 content and electrolyte leakage). Supplementation of Cd with SNP significantly reduced the Cd-induced lipid peroxidation, H2O2 content and electrolyte leakage in wheat roots. It indicated a reactive oxygen species (ROS) scavenging activity of NO. However, even upon removal of Cd-treatment solution, the levels of oxidative markers increased during 24 h recovery stage and later at 48 h these decreased. Cd treatment resulted in an upregulation of activities of antioxidant enzymes—superoxide dismutase (SOD, 1.15.1.1), guaiacol peroxidase (GPX, 1.11.1.7), catalase (CAT, 1.11.1.6), and glutathione reductase (GR, 1.6.4.2). SNP supply resulted in a reduction in Cd-induced increased activities of scavenging enzymes. The protective role of exogenous NO in decreasing Cd-induced oxidative damage was also evident from the histochemical localization of lipid peroxidation, plasma membrane integrity and superoxides. The study concludes that an exogenous supply of NO protects wheat roots from Cd-induced toxicity.

A better knowledge of genetic variability of traits related to nitrogen use efficiency (NUE) is a potential strategy to optimize N fertilization and to reduce environmental pollution without decreasing marketable yield and quality. To this aim, in this study, 13 cultivars of witloof chicory were compared with three reference cultivars known for their adaptation to low, intermediate and high N availability in the field during the vegetative phase of development. Pertinent criteria used for this study were determined by a thorough comparison of nitrogen reserve accumulation in tuberized roots during vegetative development and mobilization during the forcing process in the three reference cultivars. Cluster analysis allowed us to sort the cultivars into four main groups we named G1, G2, G3 and G4. Cultivars of group G4, better adapted to soils with high nitrogen contents (N-demanding cultivars), showed higher total N, nitrate, total amino acids (AA), glutamine contents and lower total N and AA mobilization for chicon growth than did cultivars of group G1, adapted to soils with low nitrogen content (N-sensitive cultivars). An intermediate behavior was exhibited by cultivars of groups G2 and G3, characterized as N tolerant. It is proposed that either chicory growers or breeders may take advantage of the genetic variability revealed in the present study to gain flexibility in choosing the right cultivar for the type of soil available (N-rich soil vs N-poor soil) or to adapt the level of N fertilization to the type of cultivar (N-demanding vs N-sensitive) in order to target the highest NUE for the best chicon yield and trade quality.

Cadmium (Cd) toxicity of rice (Oryza sativa L. cv. Taichung Native 1) seedlings was evaluated by the decrease in chlorophyll content and the increase in malondialdehyde (MDA) in the second leaves of rice seedlings. CdCl2 (5 μM) treatment was accompanied by a decrease in the contents of ascorbic acid (AsA) and AsA + dehydroascorbate (DHA) and in the ratios of AsA/DHA in leaves.