Free Water-Soluble Phenolics Profiling in Barley (Hordeum vulgare L.)

5 páginas, 3 figuras, 1 tabla.- et al.The phenolic profile of barley (Hordeum vulgare L.) leaves, seeds, awns, and stems, collected in two different locations from Portugal, was determined by a high-performance liquid chromatography/diode array detector (HPLC/DAD). A total of 28 compounds were identified and quantified, which included 4 phenolic acids, 6 C-glycosylflavones, and 18 O-glycosyl-C-glycosyl flavones, with some of them acylated. Distinct profiles were noticed among the analyzed materials. The greatest diversity of compounds was found in barley leaves (26 flavonoids and 2 phenolic acid derivatives), which also exhibited the highest concentration of phenolics. Isoorientin-7-O-glucoside (lutonarin) was the major compound in leaves, while, in general, the pair isovitexin-7-O-rutinoside plus isoscoparin-7-O-glucoside were the main phenolics in the other materials. Thus, barley leaves may constitute an important dietary source of protective compounds, which could be used, for example, to take profit from the wastes resulting from alcoholic drink obtainment.Zuzana Krsková is grateful to the European Union Erasmus/LLP Programme for Grant MSM 002 162 0822 and Zentiva a.s. for financial support.Peer reviewe

Free water-soluble phenolics profiling in barley (Hordeum vulgare L.)

The phenolic profile of barley (Hordeum vulgare L.) leaves, seeds, awns, and stems, collected in two different locations from Portugal, was determined by a high-performance liquid chromatography/ diode array detector (HPLC/DAD). A total of 28 compounds were identified and quantified, which included 4 phenolic acids, 6 C-glycosylflavones, and 18 O-glycosyl-C-glycosyl flavones, with some of them acylated. Distinct profiles were noticed among the analyzed materials. The greatest diversity of compounds was found in barley leaves (26 flavonoids and 2 phenolic acid derivatives), which also exhibited the highest concentration of phenolics. Isoorientin-7-O-glucoside (lutonarin) was the major compound in leaves, while, in general, the pair isovitexin-7-O-rutinoside plus isoscoparin-7-O-glucoside were the main phenolics in the other materials. Thus, barley leaves may constitute an important dietary source of protective compounds, which could be used, for example, to take profit from the wastes resulting from alcoholic drink obtainment

Experimental method for complex thermo-mechanical material analysis

An experimental system for complex thermo-mechanical material analysis is presented in this article. The system provides simultaneous measurements of tensile properties as well as heat generation in the process of tensile deformation. The cooling curve of the sample after its reversible deformation was measured. On the basis of an exponential model of a cooling body with respect to the Biot number Bi, it is possible to calculate the specific heat capacity c p , the thermal diffusivity α, and the thermal conductivity k. The method had been tested on a variety of materials and the results were compared to those in the technical literature or obtained by reference independent experiments and showed very good agreement