Automated identification of phenolics in plant-derived foods by using library search approach

Phenolic compounds may contribute to the organoleptic, commercial and nutritional characteristics of plant-derived food and beverages and their consumption has been associated with positive health benefits. Consequently, it is essential to determine the nature and distribution of these compounds in the diet. We have developed a reliable, reproducible, fast and sensitive method for the identification of phenolics using liquid chromatography interfaced to an ESI-Qq-TOF mass spectrometer, which provides mass accuracy and true isotopic pattern in MS and MS/MS. We built up a library of phenolic compounds using retention time, MS and MS/MS spectra. Fragmentation patterns in the negative ionisation mode are discussed. We have applied the automated library search in some of the components of a food supplement (propolis and lyophilisate of some vegetables) selected by its antioxidant properties. A variety of phenolic components was successfully identified.     

Urinary excretion of strawberry anthocyanins is dose dependent for physiological oral doses of fresh fruit

There is considerable interest in coloured fruits and berries as sources of biologically active anthocyanins. To examine the relationship between the oral dose and the amount excreted for anthocyanins from a food source across a physiological range of doses, volunteers were fed, in random order, four portions (100-400 g) of fresh strawberries as part of a standard breakfast. Urine was collected at 2 h intervals up to 8 h, and for the period 8-24 h. Fresh strawberries contained pelargonidin-3-glucoside as the major anthocyanin with smaller amounts of cyanidin-3-glucoside and pelargonidin-3-rutinoside. Anthocyanins were detected in the urine of all volunteers for all doses, predominantly as pelargonidin glucuronide and sulphate metabolites. There was a strong, linear relationship between oral dose and anthocyanin excretion (Pearson's product moment correlation coefficient = 0.692, p < 0.001, n = 40) which indicated that on an average, every additional unit of dose caused 0.0166 units of excretion. Within individuals, dose -- excretion data fitted a linear regression model (median R(2) = 0.93). We conclude that strawberry anthocyanins are partially bioavailable in humans with a linear relationship between oral dose and urinary excretion for doses up to 400 g fresh fruit.     

Neue Bifunktionelle Brückenfunktionen zur A1-B29-Verklammerung der beiden Insulinketten

Novel Bifunctional Bridging Functions for A1-B29 Crosslinking of the Two Insulin Chains The positions A1 and B29 of the insulin molecule are crosslinked by the new bifunctional groups U and V. These insulin derivatives are convertible by oxydative sulfitolysis into A1-B29 crosslinked hexa-S-sulfonates, which recombine by tributylphosphan/O₂ in high yields to the A1-B29 insulin derivatives, correctly reconstructing the disulfide system, and from which the bridging function is smoothly removable by acidolysis. The example of the bridging function U demonstrates that this principle is also suitable for the combination of both isolated single chains.     

Corrosion of selected ceramic materials in hot gas environment

The temperature dependence of the hot gas corrosion behaviour of various ceramic materials (Al₂O₃, ZrO₂ (Y-TZP), mullite, ZrSiO₄ and YAG) was investigated. The tests were performed in a high temperature burner rig at temperatures between 1200 °C and 1500 °C, a total pressure of 1 atm with a water vapour partial pressure of 0.24 atm, a gas flow velocity of 100 m/s and test times of about 130–300 h.

ZrO₂ (Y-TZP) showed absolutely no corrosion, however, a very high susceptibility to thermal shock and phase transformation was observed.

The other materials suffered degradation above 1300 °C. This was the consequence of the formation and evaporation of volatile hydroxides (e.g. Si(OH)₄ and Al(OH)₃). YAG showed a low corrosion rate and the formation of a protective surface layer. The corrosion susceptibility of these materials was found to be higher with increasing temperature.

Thermochemical calculations of the partial pressure of volatile species formed in reaction with water vapour, affirm the observed differences in corrosion behaviour.     

Electrical resistivity of silicon nitride-silicon carbide based ternary composites

New electrically conductive ternary composites were developed by adding 8 vol.% of ZrN or ZrB₂ to a Si₃N₄-SiC matrix. During hot pressing, ZrB₂ reacted with Si₃N₄ to form ZrSi₂, ZrN, Si and BN whereas added ZrN did not undergo any reactions in the Si₃N₄-SiC-ZrN composite. The composites modified by ZrN or ZrB₂ addition showed a lower resistivity (7 × 10³ Ω cm and 3 × 10⁻¹ Ω cm) compared to the matrix (3 × 10⁴ Ω cm). Further studies on the grain size distribution and the volume ratio of conducting and non-conducting phases excluded a percolation network of ZrN and ZrSi₂ grains. In fact, doping of SiC grains and modified grain boundaries as a consequence of the formation of liquid phases during sintering are suggested to be the reason for the significantly lower resistivity of materials containing ZrSi₂.A decrease in the composite resistivity due to a subsequent heat treatment was obtained for all hot-pressed composites.     

A New Halogen‐Free Flame Retardant Based on 9,10‐Dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide for Epoxy Resins and their Carbon Fiber Composites for the Automotive and Aviation Industries

The pyrolysis and fire behavior of halogen‐free flame‐retarded DGEBA/DMC, RTM6 and their corresponding 60 vol.‐% carbon fibers (CF) composites were investigated. A novel phosphorous compound (DOPI) was used. Its action is dependent on the epoxy matrix. DGEBA/DMC and DOPI decompose independently of each other. Only flame inhibition occurs in the gas phase. RTM6 shows flame inhibition and a condensed phase interaction increasing charring. Both mechanisms decrease with increasing irradiance, whereas in RTM6‐CF charring is suppressed at low ones. RTM6 + DOPI shows a higher LOI (34.2%) than DGEBA/DMC + DOPI and a V‐0 classification in UL 94. Adding CF only enhances the LOI, DOPI + CF leads to a superposition in LOI for DGEBA/DMC‐CF + DOPI (31.8%, V‐0) and a synergism for RTM6‐CF + DOPI (47.7%, V‐0).

     

Demonstration of a TODGA based Extraction Process for the Partitioning of Minor Actinides from a PUREX Raffinate

Abstract: Efficient recovery of minor actinides (MA) from genuine PUREX raffinate has been successfully demonstrated by the TODGA + TBP extractant mixture dissolved in an industrial aliphatic solvent TPH. The process was carried out in centrifugal contactors using an optimized flow‐sheet involving a total of 32 stages, divided into 4 stages for extraction, 12 stages for scrubbing and 16 stages for back‐extraction. Very high feed decontamination factors were obtained (Am, Cm ～ 40 000) and the recovery of these elements was higher than 99.99%. Of the non‐lanthanide fission products only Y and a small part of Ru were co‐separated into the product fraction together with the lanthanides and the MA.     

Identification of Novel Genes Involved in Hyperglycemia in Mice

Current attempts to prevent and manage type 2 diabetes have been moderately effective, and a better understanding of the molecular roots of this complex disease is important to develop more successful and precise treatment options. Recently, we initiated the collective diabetes cross, where four mouse inbred strains differing in their diabetes susceptibility were crossed with the obese and diabetes-prone NZO strain and identified the quantitative trait loci (QTL) Nidd13/NZO, a genomic region on chromosome 13 that correlates with hyperglycemia in NZO allele carriers compared to B6 controls. Subsequent analysis of the critical region, harboring 644 genes, included expression studies in pancreatic islets of congenic Nidd13/NZO mice, integration of single-cell data from parental NZO and B6 islets as well as haplotype analysis. Finally, of the five genes (Acot12, S100z, Ankrd55, Rnf180, and Iqgap2) within the polymorphic haplotype block that are differently expressed in islets of B6 compared to NZO mice, we identified the calcium-binding protein S100z gene to affect islet cell proliferation as well as apoptosis when overexpressed in MIN6 cells. In summary, we define S100z as the most striking gene to be causal for the diabetes QTL Nidd13/NZO by affecting β-cell proliferation and apoptosis. Thus, S100z is an entirely novel diabetes gene regulating islet cell function.     

Anodic oxidation of 3-amino-5-(pyrid-4-yl)-1, 2-dihydropyrid-2-one (amrinone)

The anodic behavior of the cardiotonic drug 3-amino-5-(pyrid-4-yl)-1,2-dihydropyrid-2-one 1 and of 6 compounds with similar structure was investigated at platinum and vitreous carbon electrodes in acetonitrile and in aqueous medium. Caused by the 3-amino group 1 is oxidized at a relatively small oxidation potential in an irreversible two-electron process. Depending on the addition of a strong base or a strong acid the oxidation potential vs. SCE in acetonitrile is −0.08 V (anion), +0.66 V (neutral compound), +0.93 V (monocation) or +1.15 V (dication). In H₂O a strong decrease of the oxidation potential with increasing pH was found as a reason for the sensitivity of 1 against oxygen in alkaline solution. The anodic oxidation of 3-dimethylamino-5-(pyrid-4-yl)-1, 2-dihydro-pyrid-2-one 3 in 0.1 m H₂SO₄ leads to 5-(pyrid-4-yl)-piperidine-2,3,6-trione 9a or 5-(pyrid-4-yl)-piperidine-2,3,4-trione 9b , which is also the oxidation product of 1 at small concentration. At high concentration of 1 coupling reactions at the 3-amino-group lead to dimeric products, which could not be identified.