Downregulation of pyrophosphate: d-fructose-6-phosphate 1-phosphotransferase activity in sugarcane culms enhances sucrose accumulation due to elevated hexose-phosphate levels

Analyses of transgenic sugarcane clones with 45–95% reduced cytosolic pyrophosphate: d-fructose-6-phosphate 1-phosphotransferase (PFP, EC 2.7.1.90) activity displayed no visual phenotypical change, but significant changes were evident in in vivo metabolite levels and fluxes during internode development. In three independent transgenic lines, sucrose concentrations increased between three- and sixfold in immature internodes, compared to the levels in the wildtype control. There was an eightfold increase in the hexose-phosphate:triose-phosphate ratio in immature internodes, a significant restriction in the triose phosphate to hexose phosphate cycle and significant increase in sucrose cycling as monitored by 13C nuclear magnetic resonance. This suggests that an increase in the hexose-phosphate concentrations resulting from a restriction in the conversion of hexose phosphates to triose phosphates drive sucrose synthesis in the young internodes. These effects became less pronounced as the tissue matured. Decreased expression of PFP also resulted in an increase of the ATP/ADP and UTP/UDP ratios, and an increase of the total uridine nucleotide and, at a later stage, the total adenine nucleotide pool, revealing strong interactions between PPi metabolism and general energy metabolism. Finally, decreased PFP leads to a reduction of PPi levels in older internodes indicating that in these developmental stages PFP acts in the gluconeogenic direction. The lowered PPi levels might also contribute to the absence of increases in sucrose contents in the more mature tissues of transgenic sugarcane with reduced PFP activity

Annealing study and thermal investigation on bismuth sulfide thin films prepared by chemical bath deposition in basic medium

This is a post-peer-review, pre-copyedit version of an article published in Applied Physics A 124.2 (2018): 166. The final authenticated version is available online at: http://doi.org/10.1007/s00339-018-1584-7Bismuth sulfide thin films were prepared by chemical bath deposition using thiourea as sulfide ion source in basic medium. First, the effects of both the deposition parameters on films growth as well as the annealing effect under argon and sulfur atmosphere on as-deposited thin films were studied. The parameters were found to be influential using the Doehlert matrix experimental design methodology. Ranges for a maximum surface mass of films (3 mg cm-2) were determined. A well crystallized major phase of bismuth sulfide with stoichiometric composition was achieved at 190°C for 3 hours. The prepared thin films were characterized using Grazing Incidence X-ray diffraction (GIXRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX). Second, the band gap energy value was found to be 1.5 eV. Finally, the thermal properties have been studied for the first time by means of the electropyroelectric (EPE) technique. Indeed, the thermal conductivity varied in the range of 1.20 - 0.60 W m-1 K-1 while the thermal diffusivity values increased in terms of the annealing effect ranging from 1.8 to 3.5 10-7 m2s-1This work was financially supported by the Tunisian Ministry of Higher Education and Scientific Research and by the WINCOST (ENE2016-80788-C5-2-R) project funded by the Spanish Ministry of Economy and Competitivenes

Canola oil with high antioxidant content obtained by combining emerging technologies: microwave, ultrasound, and a green solvent

In this work, the ultrasound‐assisted extraction (UAE) of canola oil from canola seeds pretreated with microwaves using ethanol 99% as solvent is studied. Different process parameters are evaluated, such as extraction time, temperature, solid:solvent ratio, and ultrasound amplitude, optimizing the process using response surface methodology. Under optimum conditions, the extraction time is decreased by up to 75% with respect to conventional extractions, obtaining an oil with a higher content of total tocopherols and canolol, and with oxidation indexes within the established standard limits. The addition of a microwave pretreatment to the UAE with ethanol 99% shows a synergic effect between both processes, improving the oil yield. The results obtained in this study show the potential of the use of UAE for the extraction of canola oil using a green solvent, reducing processing times, environmental pollution, and achieving an oil of high quality and antioxidant concentration. Practical Application: The industrial use of petroleum‐derived solvents such as hexane has problems concerning sustainability, environment, and safety. In recent years, the use of "green" solvents for the extraction of vegetable oils began to be studied; however, it is necessary to develop stages that allow improving the extraction process by increasing the yield, reducing the processing times, and optimizing the oil quality. In this sense, ultrasound allows to shorten the extraction times while microwave pretreatments applied to canola seeds generate an increase in the concentration of antioxidants in the oil, facilitating the implementation of a "green" process in the industrial production.Fil: Sánchez, Ramiro Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo y Diseño. Universidad Tecnológica Nacional. Facultad Regional Santa Fe. Instituto de Desarrollo y Diseño; ArgentinaFil: Fernández, María Belén. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Grupo Tecnologías de Semillas; ArgentinaFil: Nolasco, Susana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Grupo Tecnologías de Semillas; Argentin