Kinetics of catalytic transfer hydrogenation of some vegetable oils

Catalytic transfer hydrogenation of corn, peanut, olive, soybean, and sunflower oils has been studied with aqueous sodium formate solution as hydrogen donor and palladium on carbon as catalyst. Kinetic constants and selectivity have been determined under intensive stirring in the presence of stabilizing agents. Hydrogenation reactions followed first-order kinetics with respect to fatty acids. Besides good selectivity and short reaction time, this method offers safe and easy handling. The presence of linolenic acid retards the migration of double bonds, which explains why soybean oil is the most appropriate for this hydrogenation process.     

Computer simulation and spatial modelling in heart surgery

Two sets of muscle polypeptides showing calcium-binding capacity and intense labelling in vivo with 32P were purified and characterized from Drosophila melanogaster adult extracts. The polypeptides exhibit crossed immunoreactivity and share similar biochemical properties such as those involved in purification. They have been identified as isoforms of troponin-T (TnT) by sequence analysis of a cDNA clone isolated from an embryonic library. The two sets of TnT polypeptides correspond to the fibrillar and non-fibrillar muscle isoforms, respectively. The non-fibrillar muscle isoforms separate into two bands which are differentially expressed during development. Analysis of TnT isoforms in bee thoraces indicates that the expression of the fibrillar muscle isoform correlates with the acquisition of functional flight capability. In vivo labelling experiments reveal that the two TnT sets are readily phosphorylated. The Drosophila TnTs show calcium-binding properties by three different types of assays. Our results suggest that this property could be specific to insect TnTs and may be related to the long, extremely acidic polyglutamic carboxy-terminus present in these polypeptides, which does not occur in non-arthropod TnTs.     

Phenolic acids and flavonoids of fig fruit (Ficus carica L.) in the northern Mediterranean region

Phenolics are an important constituent of fruit quality because of their contribution to the taste, colour and nutritional properties of fruit. We have tried to evaluate the phenolic profile of fig fruit, since only limited information on that topic is available in the literature. With the HPLC-PDA system, we have identified the following phenolics: gallic acid, chlorogenic acid, syringic acid, (+)-catechin, (−)-epicatechin and rutin. Phenolics were extracted from three different fig cultivars that are commonly grown in Slovenia’s coastal region. These cultivars were ‘Škofjotka’ (‘Zuccherina’) a white type fruit, ‘?rna petrovka’ and ‘Miljska figa’, both dark type fruit. The fruit from the first and the second crop were collected and compared. In general, fruit from the second crop contained higher values of phenolics than fruit from the first crop. The analysed phenolics present at the highest content were rutin (up to 28.7 mg per 100 g FW), followed by (+)-catechin (up to 4.03 mg per 100 g FW), chlorogenic acid (up to 1.71 mg per 100 g FW), (−)-epicatechin (up to 0.97 mg per 100 g FW), gallic acid (up to 0.38 mg per 100 g FW) and, finally, syringic acid (up to 0.10 mg per 100 g FW). Both cultivars with dark fruit exhibited a higher total level of analysed phenolics, in comparison to the white fruit cultivar ‘Škofjotka’. The amounts measured are comparable to those of other fruits grown in this region. The amounts of rutin in particular are quite high and comparable to apples, for example. As a typical, seasonal fresh fruit, figs can be an important constituent of the regional diet.     

Scanning Protein Surfaces with DNA-Encoded Libraries

Understanding the ligandability of a target protein, defined as the capability of a protein to bind drug-like compounds on any site, can give important stimuli to drug-development projects. For instance, inhibition of protein–protein interactions usually depends on the identification of protein surface binders. DNA-encoded chemical libraries (DELs) allow scanning of protein surfaces with large chemical space. Encoded library selection screens uncovered several protein–protein interaction inhibitors and compounds binding to the surface of G protein-coupled receptors (GPCRs) and kinases. The protein surface-binding chemotypes from DELs are predominantly chemically modified and cyclized peptides, and functional small-molecule peptidomimetics. Peptoid libraries and structural peptidomimetics have been less studied in the DEL field, hinting at hitherto less populated chemical space and suggesting alternative library designs. Roughly a third of bioactive molecules evolved from smaller, target-focused libraries. They showcase the potential of encoded libraries to identify more potent molecules from weak, for example, fragment-like, starting points.     

Preservative efficacy screening of pharmaceutical formulations using ATP bioluminescence

The preservative challenge test is a method used to determine the efficacy of a preservation system in a pharmaceutical or cosmetic formulation. However, such testing is a labor-intensive, repetitive task often requiring days before results can be generated. Several alternatives to traditional colony-count techniques have been developed. A study using pure suspensions of Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, Candida albicans, and Aspergillus niger showed that the accuracy, repeatability, and linearity of the Pallchek luminometer ATP bioluminescence (ATP-B) system was equivalent to the traditional colony-count method. In any case, the method proved sensitive enough to follow the effect of preservatives on a number of test microorganisms, indicating the applicability of the ATP-B method for preservative screening studies in various pharmaceutical formulations.     

Analysis on exergy consumption patterns for space heating in Slovenian buildings

Problem of high energy use for heating in Slovenian buildings is analyzed with exergy and energy analysis. Results of both are compared and discussed. Three cases of exterior building walls are located in three climatic zones in winter conditions. Results of energy analyses show that the highest heating energy demand appears in the case with less thermal insulation, especially in colder climate. If the comparison is made only on the energy supply and exergy supply, the results of exergy analysis are the same as those of energy analysis. The main difference appears, if the whole chain of supply and demand is taken into consideration. Exergy calculations enable us to analyze how much exergy is consumed in which part, from boiler to building envelope. They also reveal how much energy is supplied for the purpose of heating. Results show that insulation has much bigger effect than effect of boiler efficiency. However, the most effective solution is to improve building envelope together with boiler efficiency. Better thermal insulation also makes an important contribution to the improvement of thermal comfort conditions. It causes higher surface temperatures resulting in a larger warm radiant exergy emission rate and consequently better thermal comfort.     

Calculation of the mercury accumulation in the Idrijca River alluvial plain sediments

From the historic literature on the Idrija mercury mine, it is evident that part of the smelting and mining waste was dumped into the Idrijca River. This waste was transported downstream during floods. The amount of mercury which has accumulated in the alluvial sediments of the Idrijca River until the present was studied. Mapping of Holocene river terraces of the Idrijca River was performed in order to estimate the volume of the alluvial sediment. For the purpose of the assessment of the mercury concentration, we sampled the alluvial sediments on different levels and performed an analysis of variance. The greatest variability is between the floodplain and terraces inside the same alluvial plain. Considering this fact, which determined the methodology employed for calculation, we estimated that about 2029 tons of mercury is stored in the Idrijca River alluvial sediments.