Phenolic acid content of organic and conventionally grown winter wheat

Epidemiological data suggest that consumption of whole-grain and bran may help to prevent cardiovascular diseases, diabetes and certain forms of cancer. The beneficial health effects are usually attributed to the presence of dietary fibre and bioactive secondary metabolites, including phenolic acids. Wheat is an important component of the human diet and may be a significant source of phenolic antioxidants. To date, few studies have investigated the effect of various agricultural practices on levels of secondary metabolites in crops. The aim of this work was to determine the phenolic acid content in four winter wheat cultivars, grown using conventional and organic agricultural practices. Five phenolic acids were detected by HPLC analyses. Ferulic acid was the predominant phenolic acid in the grain of all tested wheat varieties. The remaining phenolic acids, i.e. sinapic acid, p -coumaric acid, vanillic acid, and p -hydroxybenzoic acid, were present in considerably lower amounts. Significant differences among cultivars in concentration of particular phenolic acids, as well as in the total phenolic acid content were observed. The effect of various agricultural practices on phenolic acid levels in wheat grains was also analysed. Organically grown plants are usually considered to contain more secondary metabolites. In this study, however, organic agriculture did not lead to a significant increase in phenolic acids. Only a small, statistically irrelevant trend towards higher levels of phenolic acids in organic wheat samples was demonstrated

The ultra-performance liquid chromatography (UPLC) analysis of phenolics in four plant species

For the evaluation of the efficiency of in vitro systems and for standardization of commercial products the reliable fast analytical procedures are required. These are usually based on HPLC analysis. Regular HPLC separations are usually time and solvent consuming. The new achievements in analytical equipment allows to apply much faster technique UPLC for plant phytochemical analysis. The technology is quite new (developed in 2004) and in this respect there is no literature available. It was applied for separation of phenolics in the extracts of four plant species: basil (Ocimium basilicum), dandelion (Taraxacum officinale), soybean (Glycine max), mint (Mentha piperica) considered as a source of nutraceuticals researched under the project NUTRASNACK (E.C. F.P.6 contract No FOOD-CT-2005-023044). The Acquinity Ultra Performance Liquid Chromatograph (Waters) consisting of Binary Solvent Manager, Sample Manager, PDA detector and Empower Pro 2.0 software was used. The analyses were performed on an UPLC BEH C18 column (1.7mm, 50mm ´ 2.1mm) utilizing a gradient elution profile and a mobile phase consisting of 0,1% acetic acid in water and 40% AcN. The column was maintained at 50oC and at a flow rate was kept constant at 0.35 mL/min. The separation profiles obtained for four analysed species were of similar quality as the profiles obtained with HPLC. However, optimization of the separation conditions (water-acetonitrile gradient shape, column temperature) in UPLC allowed us to reduce separation time down to 5 min (basil, dandelion) and 6 min (mint and soybean); regular HPLC separation time was 50 min. The developed method simplified the analytical protocol and shortened the time of analysis just to few minutes. This an important achievement when big number of samples e.g. in vitro culture efficiency evaluation is necessary

Advanced Na[Ni 0.25

While much research effort has been devoted to the development of advanced lithium-ion batteries for renewal energy storage applications, the sodium-ion battery is also of considerable interest because sodium is one of the most abundant elements in the Earth’s crust. In this work, we report a sodium-ion battery based on a carbon-coated Fe3O4 anode, Na[Ni0.25Fe0.5Mn0.25]O2 layered cathode, and NaClO4 in fluoroethylene carbonate and ethyl methanesulfonate electrolyte. This unique battery system combines an intercalation cathode and a conversion anode, resulting in high capacity, high rate capability, thermal stability, and much improved cycle life. This performance suggests that our sodium-ion system is potentially promising power sources for promoting the substantial use of low-cost energy storage systems in the near future