Preservation of vitamins content in Cuccìa using an innovative method of processing

Abstract

Cuccìa is a traditional Sicilian food prepared by boiling whole durum wheat kernels, in water, for many hours. This process destroys the vitamins E and B contents of crude kernels. It was rated a method to prepare the Cuccìa, preserving the vitamin content. Four varieties of durum wheat were processed comparing the traditional cooking method (TR-boiling for 5/6?hours), and an innovative one (IN-grains scarification, germination, and cooking at 50?°C for 2?hours). On soups obtained the content of biotin, niacin and α-amylase activity were determined. ANOVA showed the cooking method influences biotin and niacin content having values from 0.56 and 0.72?ng ml^?1 (raw grain) and values close to 0 (TR), while only a 10% decrease (IN) respectively for both vitamins. On the contrary, α-amylase activity was reduced with IN method. The IN method combined with ancient grains, produces the soup with a good vitamin B amount.     

Simultaneous determination of phenolic compounds by means of an automated voltammetric “electronic tongue”

Zirconium(IV) selenoiodates have been synthesized under a variety of conditions. The most chemically and thermally stable sample is prepared by adding a mixture of aqueous solutions of 0.1 mol L^–1 potassium iodate and 0.1 mol L^–1 sodium selenite to aqueous solution of 0.1 mol L^–1 zirconium(IV) oxychloride. Its ion-exchange capacity for K⁺ and Pb²⁺ was found to be 3.20 and 2.35 meq g^–1 dry exchanger, respectively. The material has been characterized on the basis of chemical composition, pH titration, and thermogravimetric analysis. The effect on the exchange capacity of drying the exchanger at different temperatures has also been studied. The analytical importance of the material has been established by quantitative separation of Pb²⁺ from other metal ions.     

Analysis of curing reaction of liquid-crystalline epoxy compositions by using temperature-modulated DSC TOPEM®

Journal of Thermal Analysis and Calorimetry - The curing behaviour of the composition of a liquid-crystalline diepoxy monomer (LCEM) with the central triaromatic mesogenic group was studied using...     

Validation of an empirical RNA-ligand scoring function for fast flexible docking using RiboDock®

We report the design and validation of a fast empirical function for scoring RNA-ligand interactions, and describe its implementation within RiboDock, a virtual screening system for automated flexible docking. Building on well-known protein-ligand scoring function foundations, features were added to describe the interactions of common RNA-binding functional groups that were not handled adequately by conventional terms, to disfavour non-complementary polar contacts, and to control non-specific charged interactions. The results of validation experiments against known structures of RNA-ligand complexes compare favourably with previously reported methods. Binding modes were well predicted in most cases and good discrimination was achieved between native and non-native ligands for each binding site, and between native and non-native binding sites for each ligand. Further evidence of the ability of the method to identify true RNA binders is provided by compound selection ('enrichment factor') experiments based around a series of HIV-1 TAR RNA-binding ligands. Significant enrichment in true binders was achieved amongst high scoring docking hits, even when selection was from a library of structurally related, positively charged molecules. Coupled with a semi-automated cavity detection algorithm for identification of putative ligand binding sites, also described here, the method is suitable for the screening of very large databases of molecules against RNA and RNA-protein interfaces, such as those presented by the bacterial ribosome.     

Sequence Analysis of Polypeptide by Mass Spectrometry

The method described in this work provides a sensitive and fast technique for investigating the primary structure of peptides with molecular weight up to 3340 amu. Usually, the metastable ion kinetic energy spectra (MIKES) and collisional activated decomposition (CAD) spectra provide complementary information for the FAB mass spectra, the MIKES and CAD spectra generally contain high-mass sequence ions.     

Infrared diode laser spectroscopy of the Δυ = 2 band of NaBr using spectrum processing by Fourier transformation

The IR diode laser spectrum of the Δυ = 2 band of NaBr monomer has been observed with a heat-pipe high-temperature cell of a White cell type. Fringes due to optical reflections inside the high-temperature White cell were inherent in highly-sensitive observation of the spectrum. However, they were eliminated, as were high-frequency noises, by Fourier manipulation of the observed diode laser spectrum. The υ = 2-0 up to 6–4 vibration—rotation bands of both Na⁷⁹Br and Na⁸¹Br, 199 lines in total, were assigned in the range between 550 and 600 cm⁻¹. These data, combined with 21 mm wave data from the literature, were analysed with a least squares fit to nine Dunham Y _ij coefficients. Y₁₀ and Y₂₀ for Na⁷⁹Br were determined to be 298.73648(66) and −1.21058(19) cm⁻¹, respectively.     

Ab Initio structure determination of vaterite by automated electron diffraction

"This is a mineral about which there has been much discussion" is a typical statement about vaterite in older standard textbooks of inorganic chemistry. This polymorph of CaCO(3) was first mentioned by H. Vater in 1897, plays key roles in weathering and biomineralization processes, but occurs only in the form of nanosized crystals, unsuitable for structure determination. Its structure could now be solved by automated electron diffraction tomography from 50 nm sized nanocrystals.     

Accurate Mass Determination of Amino Alcohols by Turboionspray／Time—of—Flight Mass Spectrometry

ＩｎｔｒｏｄｕｃｔｉｏｎＡｍｉｎｏａｌｃｏｈｏｌｓａｒｅａｎｉｍｐｏｒｔａｎｔｃｌａｓｓｏｆｃｏｍｐｏｕｎｄｓｉｎｓｙｎｔｈｅｔｉｃｏｒｇａｎｉｃｒｅａｃｔｉｏｎｓ .Ｔｈｅｉｒｍｏｌｅｃｕｌｅｓｔｒｕｃｔｕｒｅｓｂｅｃｏｍｅｕｎｓｔｅａｄｙｗｈｅｎａｎａｌｙｚｅｄｂｙｅｌｅｃｔｒｏｎｉｍｐａｃｔ(ＥＩ) .ＴｈｅｆｒａｇｍｅｎｔｓｏｂｔａｉｎｅｄｆｒｏｍＥＩａｒｅｕｓｕａｌｌｙａｓ ｓｉｇｎｅｄｔｏｎｅｕｔｒａｌｌｏｓｓｅｓｓｕｃｈａｓＨ2 Ｏ ,ＣＨ3 ＯＨ (Ｆｉｇ .1) .ＥＩｉｓｎｏｔａｕｓｅｆｕｌｍｅ…     

Methods of sample preparation for determination of pesticide residues in food matrices by chromatography–mass spectrometry-based techniques: a review

Much progress has been made in pesticide analysis over the past decade, during which time hyphenated techniques involving highly efficient separation and sensitive detection have become the techniques of choice. Among these, methods based on chromatographic separation with mass spectrometric detection have resulted in greater likelihood of identification and are acknowledged to be extremely useful and authoritative methods for determination of pesticide residues. Even with such powerful instrumental techniques, however, the risk of interference increases with the complexity of the matrix studied, so sample preparation before instrumental analysis is still mandatory in many applications, for example food analysis. This article summarizes the analytical characteristics of the different methods of sample-preparation for determination of pesticide residues in a variety of food matrices, and surveys their recent applications in combination with chromatographic mass spectrometric analysis. We discuss the advantages and the disadvantages of the different methods, address instrumental aspects, and summarize conclusions and perspectives for the future.     

Bimetallic catalysis using transition and Group 11 metals: an emerging tool for C-C coupling and other reactions

Bimetallic catalysis refers to homogeneous processes in which either two transition metals (TM), or one TM and one Group?11 (G11) element (occasionally Hg also), cooperate in a synthetic process (often a C-C coupling) and their actions are connected by a transmetalation step. This is an emerging research area that differs from the isolated or tandem applications of the now classic processes (Stille, Negishi, Suzuki, Hiyama, Heck). Most of the reactions used so far combine Pd with a second metal, often Cu or Au, but syntheses involving very different TM couples (e.g., Cr/Ni in the catalyzed vinylation of aldehydes) have also been developed. Further development of the topic will soon demand a good knowledge of the mechanisms involved in bimetallic catalysis, but this knowledge is very limited for catalytic processes. However, there is much information available, dispersed in the literature, coming from basic research on exchange reactions occurring out of any catalytic cycle, in polynuclear complexes. These are essentially the same processes expected to operate in the heart of the catalytic process. This Review gathers together these two usually isolated topics in order to stimulate synergy between the bimetallic research coming from more basic organometallic studies and the more synthetic organic approaches to this chemistry.     

Photoinduced electron transfer chemistry of phthalimdes: an efficient tool for CC-bond formation

A collection of intra- and intermolecular photoinduced electron transfer (PET) reactions is presented which all are based on the phthalimide chromophore as the oxidizing species. Electron-donating groups versatile for PET processes are ethers, thioethers, amines, alkenes, arenes, and carboxylates as well as α-trialkylsilyl activated heteroatom-substituents. These reactions can be efficiently applied for the synthesis of five- and six-membered ring heterocycles, medium-sized and macrocyclic products such as macrolides, cyclopeptides, crown ethers or thioethers as well as (from intermolecular processes) Grignard-alike products.     

Mass spectrometry meets chip technology: a new proteomic tool in cancer research?

DNA chip technologies are the most exiting genomic tools, which were developed within the last few years. It is, however, evident that knowledge of the gene sequence or the quantity of gene expression is not sufficient to predict the biological nature and function of a protein. This can be particularly important in cancer research where post-translational modifications of a protein can specifically contribute to the disease. To address this problem, several proteomic tools have been developed. Currently the most widely used proteomic tool is two-dimensional protein gel electrophoresis (2-DE), which can display protein expression patterns to a high degree of resolution. As an alternative to 2-DE, a preliminary study using a new technique was employed to generate protein expression patterns from whole tissue extracts. Surface-enhanced laser desorption/ionization (SELDI) allows the retention of proteins on a solid-phase chromatographic surface (ProteinChip Array) with direct detection of retained proteins by time of flight-mass spectrometry (TOF-MS). Using this system, we analyzed eight cases of renal cell carcinoma (RCC) including normal, peripheral and central tumor tissue as well as four microdissected cases of cervical intraepithelial neoplasia (CIN) and three microdissected cases of cervix uteri carcinoma. Differentially expressed proteins were found by comparing the protein expression patterns generated using SELDI-based TOF-MS of tumor tissue with normal and neoplastic tissue, respectively. By applying this fast and powerful ProteinChip array technology it becomes possible to investigate complex changes at the protein level in cancer associated with tumor development and progression.     

Facile construction of 1,2-cis glucosidic linkage using sequential oxidation-reduction route for synthesis of an ER processing α-glucosidase I substrate

The fluorescence-labeled hexasaccharide (Glcα1-2Glcα1-3Glcα1-3Manα1-2Manα1-2Manα) was synthesized as a substrate for the processing enzyme α-glucosidase I. To construct the 1,2-cis glucosidic linkages, we employed an α stereoselective coupling using the mannosyl donor by assisted neighboring-group participation, followed by conversion of the stereochemistry of the C-2 hydroxyl group in the mannose residue using sequential oxidation of C-2 hydroxyl group to a 2-keto group and stereoselective reduction of the hydroxyl group to the gluco-configuration to provide the corresponding α-glucoside derivative. Using this strategy, the three consecutive α-glucosidic linkages were easily obtained in a stereoselective manner. Finally, the Dansyl labeled hexasaccharide derivative was used to measure the activity of processing α-glucosidase I.     

Determination of Pesticides in Carrots by Gas Chromatography–Mass Spectrometry

ABSTRACT

A sensitive and selective method was developed to determine pesticides in carrots by gas chromatography–mass spectrometry following the development of an optimized extraction procedure. The method was validated for 30 organochlorine pesticides for gas chromatography with electron capture detection obtaining limit of detection from 0.18 to 0.92?µg/kg except for cis- and trans-permenthrin. Twenty-six carrot samples were analyzed and six pesticides were detected. The results compared with the accepted maximum residue levels in correlation to crop origin.     

Ring-opening polymerization of ε-caprolactone from cellulose acetate by reactive processing

Cellulose - The internal plasticization of cellulose acetate (CA) was achieved by grafting with ε-caprolactone (CL) via reactive processing. The effect of varying concentrations of tin(II)...     

Monitoring the zinc affinity of the metallo-β-lactamase CphA by automated nanoESI-MS

Metallo-beta-lactamases are zinc containing enzymes that are able to hydrolyze and inactivate beta-lactam antibiotics. The subclass B2 enzyme CphA of Aeromonas hydrophila is a unique metallo-beta-lactamase because it degrades only carbapenems efficiently and is only active when it has one zinc ion bound. A zinc titration experiment was used to study the zinc affinity of the wild-type and of several mutant CphA enzymes. It shows that a second Zn(2+) is also bound at high ion concentrations. All samples were analyzed using mass spectrometry in combination with an automated nanoESI source. The metal-free enzyme has a bimodal charge distribution indicative of two conformational states. A completely folded enzyme is detected when the apo-enzyme has bound the first zinc. Intensity ratios of the different enzyme forms were used to deduce the zinc affinities. CphA enzymes mutated in metal ligands show decreased zinc affinity compared to wild-type, especially D120 mutants.     

Microwave-Assisted Solvent Extraction of Melamine from Seafood and Determination by Gas Chromatography–Mass Spectrometry: Optimization by Factorial Design

Melamine attracts considerable attention because of its toxicity. The determination of melamine in seafood was performed by gas-chromatography–mass spectrometry, using an optimized version of a method adopted by the U.S. Food and Drug Administration. The melamine was extracted by closed-vessel microwave-assisted solvent extraction (MAE), as a valid alternative in sample preparation, to reduce analysis time and provide less ambiguous data. The procedure was optimized by means of experimental factorial design considering the three main variables that affect this process: microwave oven power, the maximum temperature inside the extraction tube, and the hold time. The recovery of melamine in spiked samples was used as the elemental response value of the design. Temperature and hold time had a more positive effect on the response than the microwave power. A significant positive interaction was observed between oven power and hold time. A temperature of 70°C and a hold time of 1 min gave a recovery of 92 ± 5% for a microwave power of 600 W. Under these conditions, the total microwave extraction time was approximately 2 minutes, a much shorter time compared to the ultrasonic bath, which required a total time of 40 min. The repeatability of the method was approximately 3%. The limits of quantification were 0.55 mg kg^?1 for MAE and 1.9 mg kg^?1 for the ultrasonic bath; the linearity was confirmed up to 10 mg kg^?1. In conclusion, the MAE procedure was shown to be an excellent alternative to the official method.     

Porphyrin-LEGO®: synthesis of a hexafullereno-diporphyrin using porphyrins programmed for [4+2]-cycloaddition

A hexafullereno-diporphyrinoid was obtained in a sequence of cycloaddition steps using porphyrins programmed for [4+2]-cycloaddition reactions and C(60)-fullerene.