Detection of 4-aminocarminic acid in beverages and cake glaze from the German market: a food additive not approved in the EU

In the European Union, carminic acid and its ammonium, calcium, potassium or sodium salts and its aluminium lakes are approved as food additive E120. In beverages obtained from the German market 4-aminocarminic acid (“acid-stable carmine”) was detected by HPLC–PDA and LC–MS/MS. Isolation of the colorant from a liquid dye preparation used for the production of a beverage sample and subsequent NMR analysis confirmed the presence of 4-aminocarminic acid. Synthesis of ¹⁵N-4-aminocarminic acid clearly demonstrated that “acid-stable carmine” is not the ammonium salt of carminic acid, which is approved as food additive in the European Union. In fact, nitrogen in “acid-stable carmine” is covalently bound. The molecular structure of carminic acid is chemically modified and 4-aminocarminic acid does not comply with the specifications laid down for E120 in Commission Regulation (EU) No 231/2012. 4-Aminocarminic acid was also detected in the red-colored glaze of a raspberry cake and in the liquid dye preparation used for coloring this glaze.     

Long-term follow-up of early detected vulnerable children.

Made an 11-13 yr follow-up of the subsequent psychiatric histories of over 1,000 children who did or did not participate in a county-wide preventively oriented school mental health program for 1st and 3rd graders between 1958-1961. Clinical "risk" or "vulnerability" judgments were available for program Ss, and reasonably comprehensive 3rd-grade test data were available for all Ss. Early-detected vulnerable Ss were found to have disproportionately high later appearances in a community-wide psychiatric register. Retrospective analyses of the 3rd-grade test data indicate that peer judgment was by far the most sensitive predictor of later psychiatric difficulty. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A modern hardware setup for real-time turbulence measurements in two-phase flows

A modern concept of cost-effective digital signal processing hardware for measuring and analysing data from experiments investigating turbulent two-phase flows is presented. Using an array processor together with an appropriate analog-to-digital converter, conventional turbulence characteristics such as turbulence spectra, correlation functions, turbulence intensities and — scales can be evaluated in real time.     

Structure prediction of subtilisin BPN' mutants using molecular dynamics methods

In this paper we describe the achievements and pitfalls encounteredin doing structure predictions of protein mutants using moleculardynamics simulation techniques in which properties of atomsare slowly changed as a function of time. Basically the methodconsists of a thermodynamic integration (slow growth) calculationused for free energy determination, but aimed at structure prediction;this allows for a fast determination of the mutant structure.We compared the calculated structure of the mutants Met222Ala,Met222Phe and Met222Gln of subtilisin BPN' with the respectiveX-ray structures and found good agreement between predictedand X-ray structure. The conformation of the residue subjectto the mutation is relatively easy to predict and is mainlydetermined by packing criteria. When the side chain has polargroups its exact orientation may pose problems; long-range Coulombinteractions may generate a polarization feedback involvingsystem relaxation times beyond the simulation time. Changesinduced in the environment are harder to predict using thismethod. In particular, rearrangement of the hydration structurewas difficult to predict correctly, probably because of thelong relaxation times. In all conversions made the changes observedin the environment were found to be history-dependent and inparticular the hydrogen bonding patterns provided evidence formetastable substates. In all cases the structure predicted wascompared with available kinetic data and the reduced activitycould be explained in terms of changes in the configurationof the active site.     

Trends beim Einsatz von Realzeitrechnern für Forschung und Entwicklung in der Technischen Chemie

Trends in the use of real-time computers for research and development in industrial chemistry. Computers are integral parts of the complex equipment of chemical production plants. They are tools for computer aided process control. In production plants as well as in research and development laboratories, dedicated computer systems are used more and more. E. g., nearly all measuring devices will be controlled by their own microprocessors in the near future. In chemical engineering, however, the most significant developments are taking place in the software domain. The main trend in applications-software developments is the enhanced importance of the support of the plant operators by means of improved user interfaces. Within the research and development field, the software must be more flexibly adaptable to changes in the process equipment and due to changing control algorithms than in production plants. Moreover, efforts are being made to improve control by exploiting as much as possible a priori knowledge on the system in question. A current development in this direction, which will become stronger with time, is known under the heading ?expert systems”?, in which heuristic know-how of operators is made available and usable in process computers to improve control.     

Structure–Activity Relationships of 2‐Sufonylpyrimidines as Quorum‐Sensing Inhibitors to Tackle Biofilm Formation and eDNA Release of Pseudomonas aeruginosa

Drug‐resistant Pseudomonas aeruginosa (PA) strains are on the rise, making treatment with current antibiotics ineffective. Hence, circumventing resistance or restoring the activity of antibiotics by novel approaches is of high demand. Targeting the Pseudomonas quinolone signal quorum sensing (PQS‐QS) system is an intriguing strategy to abolish PA pathogenicity without affecting the viability of the pathogen. Herein we report the structure–activity relationships of 2‐sulfonylpyrimidines, which were previously identified as dual‐target inhibitors of the PQS receptor PqsR and the PQS synthase PqsD. The SAR elucidation was guided by a combined approach using ligand efficiency and ligand lipophilicity efficiency to select the most promising compounds. In addition, the most effective inhibitors were rationally modified by the guidance of QSAR using Hansch analyses. Finally, these inhibitors showed the capacity to decrease biofilm mass and extracellular DNA, which are important determinants for antibiotic resistance.     

The Effect of Composition on the Optical Properties and Hardness of Transparent Al‐rich MgO·nAl2O3 Spinel Ceramics

The study investigates the transmittance and hardness of Al‐rich spinel ceramics (MgO·nAl₂O₃, 1 ≤ n ≤ 2.5) prepared by reaction air sintering (up to closed porosity) of different ratios of fine and coarse‐grained commercial Al₂O₃ and MgO raw powders completed by subsequent hot isostatic pressing (HiP). Different compositions give rise to a wide range of presintering temperatures. With starting compositions 1 ≤ n ≤ 1.5, presintering results in a formation of single‐phase spinel, in which the excess of Al is solved. With higher Al contents (n > 1.5), however, a biphasic ceramic of stoichiometric MgAl₂O₄ and residual alumina is formed first. This excess alumina is incorporated into the spinel lattice during the final HiP at a temperature of 1750°C. Single‐phase, highly transparent spinel is obtained by increasing the Al‐content up to n = 2.5, which gives about 85% in‐line transmittance in the visible range of light and about 63% at a UV wavelength of 200 nm. Whereas the optical properties can be improved, the hardness (HV1) slightly decreases with increasing Al content. Depending on the raw powders, the hardness of samples prepared by finer powders tend to higher values enabled by the development of a bimodal microstructure with a finer grain fraction (≤2 μm) between coarser grains (≤156 μm). In contrast, samples made of coarser powders need higher sintering temperatures and exhibit, then, a monomodal microstructure of very large grains (≤622 μm) only.     

On the Mechanism of Palladium(0)-Catalyzed Reactions of Allylic Substrates with Nucleophiles. Origin of the Loss of Stereospecificity

The mechanism of the loss of stereospecificity in palladium-catalyzed nucleophilic substitution of allylic substrates has been investigated. Eight substrates (cis and trans isomers of 1a-d) and two nucleophiles (Et₂NH and NaCH(SO₂Ph)₂) were studied. In the animation reactions two pathways are responsible for the formation of anomalous inversion product, viz., isomerization of the starting material (path B, Scheme 2) and isomerization of the π-allyl intermediate via displacement of palladium by Pd(0) (path C, Scheme 2), the latter of which predominates. In the alkylation the results indicate that loss of stereospecificity is caused only by path C. The use of a more reactive substrate increased the stereospecificity of the reaction and suppressed the isomerization pathway. An analysis of the kinetics is consistent with the hypothesis that path C is the major pathway for the stereochemical loss.