Untersuchungen zur Amylosebestimmung in proteinreichen Stärkerohstoffen,insbesondere Erbsen

Investigations on the Amylose Determination in High Protein Starch Source Materials, Especially Peas. The proposed utilization of amylose rich starches requires different methods of amylose determination. In addition to laboratory methods also simple tests are important to that. Because the discussed legume starches are hardly investigated, first of all the suitability of the amperometric iodine titration had to be checked. Then a more easier work was described. In the case of routine analyses a modified test procedure was compared with the method of iodine titration.     

Halbkornmethode zur Bestimmung des Amylosegehalts in Gerste

A Half-kernel Method for Determination of the Amylose Content of Barley. A method, which can determine the amylose content of a single kernel, is of importance for the use of amylose mutants in plant breeding. In this paper a potentiometric titration for the determination of the amylose content of a matured half kernel of barley is described and the evalution of the titration-curves is discussed. This method allows to differentiate between various barley lines and varieties in genotypes which differ in amylose content.     

Histone Deacetylase 2 (HDAC2) Inhibitors Containing Boron

Histone deacetylase enzymes (HDACs) are responsible for the global silencing of tumour-suppressor genes. Treatment with a histone deacetylase inhibitor (HDACi) can reverse this process and restore normal cell function. Herein, we report a small series of boron-based (boronic acid, boronate ester and closo-1,2-carborane) HDAC2 inhibitors with IC₅₀ values in the nanomolar range. The boronate ester 4 b was the most potent compound assessed in this study (IC₅₀=40.6±1.5 nM), followed closely by the 1,2-closo-carborane (IC₅₀=42.9±1.5 nM). Compound 4 b exceeds the potency of the related gold-standard HDAC pan-inhibitor vorinostat ( 1 ) toward this particular HDAC isoform.     

Design and synthesis of foam glasses from recycled materials

Recycling has emerged as an environmental key point due to the diminishing of natural resources and the generation of ever-increasing amounts of industrial solid wastes. Glass wastes are among the materials that attract great interest in the recycling concept. This work presents the results of foams production from four series of compositions. The first series comprises powders of a sodium-calcium-silicate sheet glass cullet as the main component, an alkali-earth aluminosilicate glass as an additive, and a reagent grade silicon carbide (SiC) powder as gassing agent. In the second series, the glass cullet was used in combination with fly ashes (FLA) as main components, while SiC waste from abrasive paper served as foaming agent. In the third and fourth series, carbonates (calcite and dolomite) were used for foaming powder mixtures composed of sheet glass cullet and FLA, and powdered cathode ray tube panel glasses, respectively. All the processing parameters, including the main components, the nature and content of foaming agents are shown to play a crucial role on the foaming ability and final properties of the glass foams.     

Wear characteristics of some internally lubricated and reinforced engineering polymer composites

An interesting characteristic of abrasion is the dependence of the wear rate on the particle size of the abrasive grits used to lubricate the abrasive papers. Three types of polymers, PTFE, PA, PI, several of their composites, and three metals were selected for studying the effect of particle size on wear rate. The pins were abraded against Sic abrasive papers of various mesh sizes under constant loading in multi-pass conditions. For some of the polymers and their composites (PA and PEI) the size effect on wear rate was similar to that for the metals. Beyond a critical particle size, no increase in wear was found with increasing particle size. On the other hand, PTFE, PI, and their composites showed the opposite effect. SEM and EDAX were used to investigate the related mechanisms.     

Elektrochemische Adamantylierung von reduktiv dehalogenierbaren Chinolinen

Electrolytic Adamantylation by Reductive Coupling of Quinolinylhalides in the Presence of 1-Bromoadamantane Electrochemically generated anion radicals of a number of halogen-substituted quinolines 1 a–g dehalogenate in N,N-dimethylformamide to halogen anions and radicals, which may stabilize by hydrogen abstraction from the solvent. In the presence of 1-bromoadamantane the fragments of reductive dehalogenation may be used synthetically for indirect generation of 1-bromoadamantane-radicals, which react predominantly to cross-coupled 2- and 7-monoadamantylated dihydroquinoline- and quinoline-structures, independent of the original halogen position. If C-2 is blocked, adamantylation takes place in the carbocyclic ring. Product distribution and cyclic-voltammetric results are discussed in terms of mechanism.     

Detection of cauliflower mosaic virus by the polymerase chain reaction: testing of food components for false-positive 35S-promoter screening results

 Today DNA-based techniques are very common for the detection of genetically modified organisms (GMOs) in food products. For fast and easy detection of GMOs, polymerase chain reaction (PCR) screening methods, which amplify common transgenic elements, are applied in routine analysis. These techniques do not allow differentiation between GMOs and the natural occurrence of transgenic elements, such as the 35S-promoter of cauliflower mosaic virus (CaMV) or the NOS-terminator of Agrobacterium tumefaciens, and thus may result in false-positive detection of GMOs. In this study we evaluated three different existing 35S screening systems and report the development of two new CaMV-specific PCR systems. These PCR systems based on CaMV-specific genes allow the identification of positively screened 35S food samples as naturally virus-infected products or plants. Seven food samples tested positive in routine 35S screening analysis and negative in GMO specific systems were investigated using the new virus-specific PCR systems. In all seven samples CaMV was detected. Received: 26 April 1999 / Revised version: 28 June 1999