bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of clay addition on the morphology and thermal behavior of polyamide 6
Authors: Li Ting‐Cheng , Ma Jianhua , Wang Min , Tjiu Wuiwui Chauhari , Liu Tianxi , Huang Wei
Published: October 2006

The nanostructure, morphology, and thermal properties of polyamide 6 (PA6)/clay nanocomposites were studied with X‐ray scattering, differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). The wide‐angle X‐ray diffraction (WAXD) and TEM results indicate that the nanoclay platelets were exfoliated throughout the PA6 matrix. The crystallization behavior of PA6 was significantly influenced by the addition of clay to the polymer matrix. A clay‐induced crystal transformation from the α phase to the γ phase for PA6 was confirmed by WAXD and DSC; that is, the formation of γ‐form crystals was strongly enhanced by the presence of clay. With various clay concentrations, the degree of crystallinity and crystalline morphology (e.g., spherulite size, lamellar thickness, and long period) of PA6 and the nanocomposites changed dramatically, as evidenced by TEM and small‐angle X‐ray scattering results. The thermal behavior of the nanocomposites was investigated with DSC and compared with that of neat PA6. The possible origins of a new clay‐induced endothermic peak at high temperature are discussed, and a model is proposed to explain the complex melting behavior of the PA6/clay nanocomposites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1191–1199, 2007
Epicardium‐derived cells are important for correct development of the Purkinje fibers in the avian heart
Authors: Eralp Ismail , Lie‐Venema Heleen , Bax Noortje A.M. , Wijffels Maurits C.E.F. , Van Der Laarse Arnoud , Deruiter Marco C. , Bogers Ad J.J.C. , Van Den Akker Nynke M.S. , Gourdie Robert G. , Schalij Martin J. , Poelmann Robert E. , Gittenberger‐De Groot Adriana C.
Published: October 2006

During embryonic development, the proepicardial organ (PEO) grows out over the heart surface to form the epicardium. Following epithelial‐mesenchymal transformation, epicardium‐derived cells (EPDCs) migrate into the heart and contribute to the developing coronary arteries, to the valves, and to the myocardium. The peripheral Purkinje fiber network develops from differentiating cardiomyocytes in the ventricular myocardium. Intrigued by the close spatial relationship between the final destinations of migrating EPDCs and Purkinje fiber differentiation in the avian heart, that is, surrounding the coronary arteries and at subendocardial sites, we investigated whether inhibition of epicardial outgrowth would disturb cardiomyocyte differentiation into Purkinje fibers. To this end, epicardial development was inhibited mechanically with a membrane, or genetically, by suppressing epicardial epithelial‐to‐mesenchymal transformation with antisense retroviral vectors affecting Ets transcription factor levels (n = 4, HH39‐41). In both epicardial inhibition models, we evaluated Purkinje fiber development by EAP‐300 immunohistochemistry and found that restraints on EPDC development resulted in morphologically aberrant differentiation of Purkinje fibers. Purkinje fiber hypoplasia was observed both periarterially and at subendocardial positions. Furthermore, the cells were morphologically abnormal and not aligned in orderly Purkinje fibers. We conclude that EPDCs are instrumental in Purkinje fiber differentiation, and we hypothesize that they cooperate directly with endothelial and endocardial cells in the development of the peripheral conduction system. Anat Rec Part A, 2006. © 2006 Wiley‐Liss, Inc.
Lower prevalence of chondrocalcinosis in Chinese subjects in Beijing than in white subjects in the United States: The Beijing Osteoarthritis Study
Authors: Zhang Yuqing , Terkeltaub Robert , Nevitt Michael , Xu Ling , Neogi Tuhina , Aliabadi Piaran , Niu Jingbo , Felson David T.
Published: October 2006

Objective

Chondrocalcinosis, which can promote joint inflammation and cartilage degeneration, is highly prevalent in elderly white subjects. Data on its prevalence are scarce in other ethnic populations. This study was undertaken to compare the prevalence of chondrocalcinosis in Chinese subjects with that in white subjects.

Methods

We recruited a random sample of Beijing residents ages ≥60 years. Participants underwent standard weight‐bearing anteroposterior knee radiography and posteroanterior hand radiography using the protocols developed in the Framingham Osteoarthritis Study. Radiographic chondrocalcinosis was defined as present in a knee or wrist when there was evidence of definite linear cartilage calcification. We compared the prevalence of chondrocalcinosis in Chinese subjects with that in white subjects using age‐standardized prevalence ratios. We used identical methods to collect samples of tap water from 2 cities and measured their levels of calcium, magnesium, and phosphate in the same laboratory.

Results

Chinese subjects had a much lower prevalence of knee chondrocalcinosis (1.8% in men, 2.7% in women) than did white subjects (6.2% in men, 7.7% in women), with the age‐standardized prevalence ratio being 0.34 (95% confidence interval [95% CI] 0.20–0.54) and 0.43 (95% CI 0.31–0.59) in men and women, respectively. Wrist chondrocalcinosis was rare in elderly Chinese subjects (prevalence 0.3% in men and 1.0% in women), with the age‐standardized prevalence ratio being 0.06 (95% CI 0.01–0.18) in Chinese men and 0.18 (95% CI 0.10–0.30) in Chinese women. Calcium levels in the tap water in Beijing were 15‐fold higher than in Framingham, whereas no difference was found in magnesium and phosphate levels.

Conclusion

Knee chondrocalcinosis and wrist chondrocalcinosis are far less common in Chinese subjects in Beijing than in US white subjects in Framingham, Massachusetts. Given the current lack of understanding of the etiology of chondrocalcinosis, further epidemiologic studies of the impact of genetic and environmental factors on occurrence of chondrocalcinosis are indicated.
Increased serum levels of soluble fractalkine (CX3CL1) correlate with disease activity in rheumatoid vasculitis
Authors: Matsunawa Mizuho , Isozaki Takeo , Odai Tsuyoshi , Yajima Nobuyuki , Takeuchi Hiroko T. , Negishi Masao , Ide Hirotsugu , Adachi Mitsuru , Kasama Tsuyoshi
Published: October 2006

Objective

To determine levels of soluble fractalkine (sFkn) in rheumatoid arthritis (RA) patients with and without rheumatoid vasculitis (RV), and to assess the relationship of sFkn levels to disease activity.

Methods

Serum was obtained from 98 RA patients (54 without vasculitis, 36 with extraarticular manifestations but without histologically proven vasculitis, and 8 with histologically proven vasculitis) and from 38 healthy individuals. Levels of sFkn were measured by enzyme‐linked immunosorbent assay. Expression of Fkn and CX3CR1 was quantified by real‐time polymerase chain reaction. Vasculitis disease activity was assessed using the Birmingham Vasculitis Activity Score and the Vasculitis Activity Index.

Results

Serum sFkn levels were significantly higher in patients with RA than in controls and were significantly higher in RA patients with RV than in those without vasculitic complications. Statistically significant correlations were observed between serum sFkn levels in RA patients and levels of C‐reactive protein, rheumatoid factor, immune complex, and complement. In the RV group, sFkn levels also correlated with disease activity. Immunohistochemical analysis indicated that Fkn levels were associated mainly with endothelial cells in vasculitic arteries. In addition, expression of CX3CR1 messenger RNA was significantly greater in peripheral blood mononuclear cells from patients with active RV than in those from other RA patients or controls. Notably, serum sFkn levels were significantly diminished following successful treatment and clinical improvement.

Conclusion

These findings suggest that Fkn and CX3CR1 play crucial roles in the pathogenesis of RV and that sFkn may serve as a serologic inflammatory marker of disease activity in RA patients with vasculitis.
A rapid liquid chromatography–tandem mass spectrometry method for quantification of a biologically active molecule camboginol in the extract of Garcinia cambogia
Authors: Chattopadhyay Sunil K. , Kumar Satyanshu
Published: November 2006

A liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method for the determination of camboginol in the extract of fruit rinds of Garcinia cambogia has been developed. Separation was achieved isocratically on an RP C18 column using a solvent system consisting of a mixture of acetonitrile–water (9:1) and methanol–acetic acid (99.5:0.5) in the ratio of 30:70 as mobile phase at a flow rate of 0.4 mL/min. A multiple reaction monitoring (MRM) method was developed for quantification of camboginol in the fruit rinds extract of G. cambogia using MRM transitions of m/z 601.4 → m/z 176.7 and m/z 601.4 → m/z 448.9, respectively. The calibration curve based on peak area against concentration was linear up to 50 ng/mL with a detection limit of 0.5 ng/mL. The method showed satisfactory reproducibility with a coefficient of variation of less than 6%. The method was successfully applied for quantification of camboginol in different Garcinia extracts. Copyright © 2006 John Wiley & Sons, Ltd.
Interplay Between Cation–π, Anion–π and π–π Interactions
Authors: Quiñonero David , Frontera Antonio , Garau Carolina , Ballester Pablo , Costa Antoni , Deyà Pere M.
Published: October 2006

The interplay between three important noncovalent interactions involving aromatic rings is studied by means of high level ab initio calculations. They demonstrate that very strong synergic effects are present in complexes where either cation–π or anion–π and π‐‐π interactions coexist. These strong synergic effects have been studied using the “atoms in molecules” theory and the physical nature of the interactions investigated by means of the molecular interaction potential with polarization (MIPp).
Determination of Aluminum by Adsorptive Cathodic Stripping Voltammetry with 1,2‐Dihydroxyanthraquinone‐3‐Sulfonic Acid (DASA): Effect of Thin Mercury Film Electrode
Authors: Thomas Shaun D. , Davey David E. , Mulcahy Dennis E. , Chow Christopher W. K.
Published: November 2006

An analytical technique for aluminum (Al) based upon the complexation reaction between Al and the ligand – DASA (1,2‐dihydroxy‐anthraquinone‐3‐sulfonic acid) has previously been implemented successfully at the hanging mercury drop electrode (HMDE). There are several advantages of using mercury film electrodes (TMFE) over the HMDE, particularly if disposal of mercury is of concern. The novelty of using TMFE for adsorptive cathodic stripping voltammetry (ACSV) of Al – DASA is demonstrated in this paper. The peak potential used for the detection of Al in this system was at −1.15 V (vs. Ag/AgCl). The method produced a limit of detection (LOD) of 1 μM (n=5) and a linear working range of 1–20 μM Al. Atomic force microscopy methods were used to investigate the nature of the TMFE and its interaction with DASA. The mercury droplets on the TMFE have a limited volume and this may lead to overloading of the electrode at relatively low concentrations of DASA. Interferences from Fe, Ca, Zn and Mg were investigated with only Fe appearing to interfere with the Al‐DASA system. Two masking agents (o‐phenanthroline and 2,2′‐bipyridyl) were shown to be effective at preventing the Fe interference.
Nickel Hexacyanoferrate‐Based Sensor Electrode for the Detection of Nitric Oxide at Low Potentials
Authors: Krylov Andrey V. , Lisdat Fred
Published: November 2006

Recently transition metal hexacyanoferrates, analogues of Prussian Blue, have found application in electroanalysis for the detection of biologically relevant species. Our study describes the development of a novel electrode based on nickel hexacyanoferrate (NiHCF) for the sensorial NO determination. A NiHCF layer was deposited on platinum by cyclic voltammetry in a solution of nickel (II) chloride and potassium hexacyanoferrate (III). The electrode was found to be active for NO reduction. The interaction with the radical was studied voltammetrically within the range from 0 V up to +0.4 V vs. Ag/AgCl/1 M KCl. The most appropriate potential for an amperometric detection was determined to be +0.25 V due to the advantageous signal/noise ratio. The sensitivity of the electrodes was found to be 2.0–2.3 A M−1 cm−2. The sensor response of the most important interferents for NO analysis, hydrogen peroxide, ascorbic acid and nitrite, was measured and determined to be sufficiently low.
Screening of drug metabolism by CE
Authors: Zhang Jie , Lou Yijia , Hoogmartens Jos , Van Schepdael Ann
Published: November 2006

The use of CE for rapid assessment of metabolic stability of drugs with cytochrome P450 (CYP) enzymes, based on relative rates of reduced nicotinamide adenine dinucleotide phosphate (NADPH) consumption and nicotinamide adenine dinucleotide phosphate (NADP) production, was investigated. The separation conditions were as follows: capillary, 80.5 cm (75 µm id, 72 cm effective length for UV detection, 58 cm effective length for fluorescence detection); 25 mM sodium phosphate buffer (pH 8.8); 28 kV (80 µA) applied voltage; UV, 260 nm; fluorescence detection, excitation wavelength, 310 nm, emission wavelength, 418 nm; capillary temperature, 25°C. For UV detection, the incubation conditions were as follows: CYP3A4: 20 pmol/mL; NADPH: 1 mM; EDTA: 1 mM; concentration of the substrate: 5–10 times its reported literatureKm value; temperature: 37°C; incubation time: 15 min. For fluorescence detection, the concentrations were reduced to CYP3A4: 4 pmol/mL, NADPH: 20 µM, EDTA: 20 µM and substrate: 10 µM. Blank incubations were performed in the absence of substrate. Compared with the blank, significant differences were found for the consumption of NADPH and the production of NADP. The development of this assay system allows rapid assessment of metabolic stability relative to standard compounds, as well as potential identification of the major CYP involved in the metabolism. It would reduce the backlog of compounds that require LC/MS analysis, and thereby expedite the process of metabolic stability screening.
Eigenmobilities in background electrolytes for CZE. V. Intensity (amplitudes) of system peaks
Authors: Hruška Vlastimil , Štědrý Milan , Včeláková Kateřina , Lokajová Jana , Tesařová Eva , Jaroš Michal , Gaš Bohuslav
Published: November 2006

We present a mathematical model of CZE based on the concept of eigenmobilities – the eigenvalues of matrix M tied to the linearized governing equations of electromigration, and the spectral decomposition of matrix M into matrices of amplitudes Pj. Any peak in an electropherogram, regardless of whether it is an analyte peak or a system peak (system zone), is matched with its matrix Pj. This enables calculation of the peak parameters, such as the transfer ratio and the molar conductivity detection response (which give the indirect detection signal and the conductivity detection signal, respectively), when the initial disturbance caused by the injection of the sample is known. We also introduce new quantities, such as the generalized transfer ratio and the conductivity response of system zones, and show how the amplitude (intensity, area) of the analyte peaks and the system peaks can be calculated. We offer a free software, PeakMaster (http://www.natur.cuni.cz/gas), which yields this information in a user‐friendly way.
Volatiles from submerged and surface‐cultured beefsteak fungus, Fistulina hepatica
Authors: Wu Shimin , Zorn Holger , Krings Ulrich , Berger Ralf G.
Published: November 2006

Cultures of Fistulina hepatica DSMZ 4987 were grown submerged in standard nutrition solution (SNS) or on oak wood powder (OWP). After cell disintegration, the volatile constituents were isolated by continuous liquid–liquid extraction (CLLE) and investigated by high‐resolution gas chromatography coupled to mass spectrometry (HRGC–MS). The surface cultures produced 53 major volatile compounds, while 39 major volatile compounds were found in the submerged cultures. The surface cultures produced several aldehydes, methoxybenzenoids and terpenes, which were absent in the submerged cultures. A strong mushroom aroma was emitted by the surface cultures only. Twenty compounds, mainly long‐chain fatty acids and methyl esters thereof, and short chain aliphatic alcohols, were common to both systems. Copyright © 2006 John Wiley & Sons, Ltd.
Essential oil composition of Agastache anethiodora Britton (Lamiaceae) infected by cucumber mosaic virus (CMV)
Authors: Bruni Renato , Bianchi Alberto , Bellardi Maria Grazia
Published: November 2006

Giant hyssop, Agastache anethiodora Britton, cultivated at the Herb Garden of Casola Valsenio, Italy, has been found for the first time naturally infected by cucumber mosaic virus (CMV). Characteristic symptoms on the leaves were chlorotic or yellow mosaic, ring and line patterns and malformation, followed by yellowing and stunting of the entire plant. CMV was mechanically transmitted to species of the families Chenopodiaceae and Solanaceae and identified by applying PAS–ELISA and RT–PCR techniques. The essential oil of both healthy and CMV‐infected plants has been evaluated by means of GC–FID and GC–MS, with the object of identifying composition differences caused by the disease. The infection of A. anethiodora by CMV was found to induce significant reduction in the yield of essential oil and several changes in the relative composition of the main components: pulegone, menthone, iso‐menthone, methyl chavicole and limonene. Methyl chavicole content, in particular, was drastically reduced. The importance of the phytopathological status of essential oil‐bearing plants is outlined. Copyright © 2006 John Wiley & Sons, Ltd.
Thermal degradation of precursors and formation of flavour compounds during heating of cereal products. Part II. The formation and changes of volatile flavour compounds in thermally treated malt extracts at different temperature and pH
Authors: Przybylski R. , Kamiński E.
Published: November 2006

The effect of temperature and pH on the formation and changes of volatile flavour compounds in thermally treated malt extracts was studied. The dependence of thermal treatment parameters on organoleptic properties of the extracts was stated.

Alkaline pH of the medium was found to promote the formation of the compounds yielding a caramel odour. The most desirable organoleptic characteristics were obtained at pH 4.0‐5.5 and temperature 140 °C. Thirty compounds typical for nonenzymatic browning were identified.
Akalorische Verbindungen mit fettähnlichen funktionellen Eigenschaften (Pseudofette)
Authors: Mieth G. , Elsner A. , Brückner J. , Weiss A. , Behrens H.
Published: November 2006

Die Übersichtsarbeit behandelt Synthese, Charakterisierung, physiko‐chemische und ernährungsphysiologische Eigenschaften akalorischer fettähnlicher Verbindungen (Pseudofette). wobei Saccharose‐Fettsäureester, Glycerolether und Glyceroldicarbonsäureester besondere Berücksichtigung finden. Weiterhin wird ein Ausblick auf andere zur Fettsubstitution potentiell geeignete Verbindungsklassen, wie Polycarbonsäure‐, Polyglycerol‐ und Polyglycolderivate gegeben.
Über die Bestimmung der Estergruppenverteilung im Pektin durch Fraktionierung an DEAE‐Cellulose
Authors: Anger H. , Dongowski G.
Published: November 2006

Die Ionenaustauschchromatographie von Pektin an DEAE‐Sephacell erlaubt es, zwischen statistischer und blockweiser Anordnung der freien Carboxylgruppen bei Veresterungsgraden (VG) zwischen 20 und 90% zu unterscheiden. Eine statistische Verteilung freier Carboxylgruppen führt im VG‐Bereich von 15 bis 95% zu einer linearen Abhängigkeit zwischen dem VG und der für die Desorption notwendigen Phosphatkonzentration, die über eine Dichtemessung bestimmt wird. Für diese Präparate läßt sich aus dem Chromatogramm eine VG‐Verteilung unter der Voraussetzung berechnen, daß mit Präparaten ähnlicher Molmasse kalibriert worden ist.
Beeinflussung funktioneller Eigenschaften von Proteinen durch gekoppelte mechanolytische und chemische Modifizierung
Authors: Kroll J. , Gassmann B. , Proll J. , Grütter B.
Published: November 2006

Schon bei kurzzeitiger Schwingmahlung reicht der Energieeintrag aus, um Proteine in Gegenwart von Säureanhydriden zu acylieren. Je nach Protein oder Proteinrohstoff sowie der Art und Menge des beigefügten Anhydrids werden 30–60% der £‐Aminogruppen des Lysins blockiert. Als Folge von Mechanolyse und Acylierung verbessern sich für Lebensmittelzwecke in typischer Weise die Löslichkeitsprofile und andere funktionelle Eigenschaften. Am Beispiel von Casein wird gezeigt, daß sich das Ausmaß der bei kurzer Schwingmahldauer mechanolytisch erreichbaren Verschäumbarkeit und Schaumstabilität durch gleichzeitige Acetylierung noch steigern läßt. Eine merkliche Erhöhung des Wasserbindungsvermögens tritt bei Acetylierungsgraden über 40% ein. Die molekularen Vorgänge bei der Kopplung von Mechanolyse und Acylierung von Proteinen und deren Auswirkung auf die funktionellen Eigenschaften werden diskutiert.
Microecology of the gastrointestinal tract and the immunological status under food allergy
Authors: Kuvaeva I. B. , Orlova N. G. , Veselova O. L. , Kuznezova G. G. , Borovik T. E.
Published: November 2006

In children suffering from food allergy the microecology of the gut and the immune status were examined. As a rule, sensitization due to the penetration of the epithelial barrier of the intestinum by macromolecules of the food is not accompanied by deficiency of secretory IgA. In all cases dysbacteriosis of different degree was observed with a characteristic picture of deficiency of Bifidobacteria and Lactobacilli combined with rising numbers of Enterobacteriaceae. Correlations to an altered immune response are obvious.
Adaptation of Pope and Stevens method for rapid determination of the amino nitrogen content in certain raw materials and animal products
Authors: Fik M. , Surówka K.
Published: November 2006

The present study is a continuation of experiments on adaptation of POPE And STEVENS method for rapid determination of proteolytic enzyme activity and protein hydrolysis intensity of food products. The results of the amino nitrogen content of certain meat products are presented by using the earlier described modified method. It was found that when determining amino nitrogen in such raw materials and products as poultry, beef, pork, fresh‐water fish and their hydrolyzates, the traditional and colorimetric methods are equal. Good accuracy, specificity and usefulness were qualities noted for the latter method in repeated and routine experimentation.
Size distribution of casein micelles during milk coagulation
Authors: Omar Mohamed M.
Published: November 2006

Electron microscopy was employed to study the size distribution and the surface to volume ratios of casein micelles in coagulum from raw milk, heated milk and milk enriched with calcium chloride before the heating process. The particles size distribution of milk protein was changed by heating resulting in an increase in the free subunits of smaller size and the surface to volume ratios. On the other hand the clotting time was prolonged. Depression in the clotting time and surface to volume ratios was occurred by adding calcium chloride to the milk before the heating process to retard the formation of complex between the whey protein and milk casein.
Estimation of the daily intake of nitrates and nitrites which children six to eleven years old, who attend primary schools in the City of Havana, may consume
Authors: Roché M. O. García , Bécquer A. , Moraleza N.
Published: November 2006

In the present article information is given as to the estimated amounts of nitrates and nitrites, which about 12000 children (6 to 11 years of age) who attend semiboarding school system in primary schools of Plaza district in the City of Havana, may consume through foods offered by the Centralized Kitchen “Manuel Ascunce” and at home. The used methods were: The determination of nitrates and nitrites in foods reported by the Mixed Committee FAO/OMS in 1976 using a reducing column containing cadmium described by Follet et al. in 1963, the nutritional survey through individual score in 24 h normed by our institute and the variance analysis of simple classification. Estimated quantities of nitrates and nitrites, which these children may consume according to the offer of food they receive, are 34,3 mg of NaNO3and 1,3 mg of NaNO2. These values are below those recommended as acceptable daily intake reported by the Mixed Committee FAO/OMS. Therefore, there does not seem to exist a risk to health through consumption of nitrates and nitrites by the population under investigation.
Electrochemical detection in HPLC. Part January Principles, techniques and instrumentation
Authors: Štulík K. , Pacáková V.
Published: November 2006

Electrochemical detection techniques in high‐performance liquid chromatography are critically surveyed. The general principles of electrochemical detection are outlined and potentiometric, polarographic, voltammetric, coulometric, conductometric and high‐frequency detectors are described. The measuring techniques and detector performance are discussed and the operation parameters of electrochemical detectors are briefly compared with the other, most common HPLC detectors.
Starch as a functional component of food systems
Authors: Braudo E. E.
Published: November 2006

Starch and other carbohydrates of D‐glucose series bind sodium ions but don't bind calcium ones. The affinity of β‐glucosides to sodium ions is much stronger than the affinity of D‐glucose and of α‐glucosides. Some other interrelations between the components of starch‐containing food systems are briefly discussed.
Ein Beitrag zur postreaktiven Seleneliminierung aus selenkatalysierten Kjeldahl‐Aufschlüssen
Authors: Engler J. , Kathe U. , Georgi E.
Published: November 2006

Es wird ein Verfahren zur postreaktiven Selenelimierung von selenkatalysierten KJELDAHL‐Aufschlüssen für die Stickstoffbestimmung vorgestellt. Das Verfahren beruht darauf, daß der Aufschlußlösung ein Reduktionsmittel zur Selenit‐ und Selenatreduktion in Kombination mit das Aufschlußmedium beeinflussenden Stoffen zugesetzt wird, wodurch eine praktisch vollständige Fällung als Selen erreicht wird. In einem weiteren Verfahrensschritt erfolgt der Abbau des Reduktionsmittelüberschusses, damit dadurch keine Störung der Ammoniak‐/Ammoniumionenanalytik eintritt. Die Ergebnisse der experimentellen Prüfung des Verfahrens werden angegeben.
Thermodynamic compatibility of proteins in aqueous media Part 3. Studies on the role of intermolecular interactions in the thermodynamics of compatibility of proteins according to the data of dilution enthalpies
Authors: Polyakov V. I. , Popello I. A. , Grinberg V. Ya. , Tolstoguzov V. B.
Published: November 2006

The flow microcalorimetric method was used to determine the enthalpies of diluting solutions of ovalbumin, bovine serum albumin, casein, soybean globulin fraction, thermotropic aggregates of ovalbumin, mixtures of ovalbumin – bovine serum albumin, casein – soybean globulin fraction, and ovalbumin – thermotropic aggregates of ovalbumin in water. The calorimetric data obtained were compared with the data on phase equilibrium in the systems Water – Ovalbumin – Bovine serum albumin, Water – Casein – Soybean globulin fraction, Water – Ovalbumin – Thermotropic aggregates of ovalbumin. Intermolecular interactions have been shown to play a significant role in the thermodynamics of protein compatibility.
Subunit structure of Vicia faba legumin and implications for the improvement of protein quality
Authors: Horstmann C. , Müntz K.
Published: November 2006

Legumin, the main storage protein of Vicia faba seeds. consists of the two different subunit types A and B. Each subunit is composed of two polypeptide chains, one acidic (α) and one basic (β) linked by disulphide bridges. In each subunit type specific α‐β‐pairs occur, in type A α‐ as well as β‐polypeptides contain methionine, whereas in both the constituent polypeptides of type B subunits methionine is lacking. Since the specific α‐β‐pairs reflect their origin from a common precursor and hence from a single gene for each subunit, it seems worthwhile to look for Vicia varieties containing an increased ratio of type A/B subunits and therefore a legumin with a higher content of the nutritionally limiting amino acid methionine. Results of such a screening are presented.
Plasteins. Their preparation, properties, and use in nutrition
Authors: Belikov V. M. , Gololobov M. Yu.
Published: November 2006

The theoretical and practical aspects of the plastein reaction, which consist in the formation of a gel following the addition of an endopeptidase to a concentrated solution of a partial protein hydrolysate. are examined and the properties and possibilities of using plasteins in nutrition are discussed. It is shown that valuable protein food products can be obtained with the aid of the plastein reaction from proteins with an unbalanced amino acid composition and from chemically synthesized amino acids. Other applications of plasteins in nutrition are discussed and the studies carried out hitherto on the mechanism and driving forces of plastein formation are considered.
Contribution of protein hydrophobicity to its functionality
Authors: Nakai S. , Li‐Chan E. , Hayakawa S.
Published: November 2006

HANSCH analysis for quantitative structure‐activity relationship (QSAR) was applied to aspartyl proteinases and it was found that higher hydrophobicity, tighter molecular structure, and lower charge are required for milk clotting enzymes compared to proteolytic enzymes. For simplicity in analysis of food proteins, the use of fluorescence hydrophobicity, solubility and steric relating parameters, e. g., SH‐SS content and viscosity, are used instead of hydrophobic, electrical and steric parameters in the original QSAR concept. Solubility of milk and soy proteins after different heat treatments was investigated and it was found that aromatic hydrophobicity measured by anilinonaphthalenesulfonate fluorometry and by phenyl‐Sepharose chromatography showed better correlation than aliphatic cis‐parinarate (CPA) hydrophobicity. The use of CPA hydrophobicity in conjunction with solubility is, therefore, justified in an attempt to avoid multicollinearity in regression study.

Significant correlations were found for emulsifying and fat binding capacity of both unheated and heated food proteins when the apparent hydrophobicity with CPA was used as a predictor variable. For foaming property, CPA hydrophobicity measured for unfolded protein (Se) and viscosity played important roles. Se and SH‐group content showed good correlation with thermal functionality of proteins.

Emulsifying and fat binding properties of crude salt extracts of meat proteins from beef and fish which had been subjected to different processing conditions were explained by using CPA hydrophobicity, solubility and SH‐group content.
Kinetic description of proteolysis. Part 1. Peptic hydrolysis of proteins isolated from chicken heart: Optimization in terms of time and substrate concentration
Authors: Belikov V. M. , Kudinova E. G. , Vorob'Ev M. M.
Published: November 2006

Simple equation for the total rate of proteolysis is proposed. The equation, based on the real mechanism of proteolysis includes the substrate concentration and some functions of the degree of hydrolysis. These functions are experimentally determined in the case of peptic hydrolysis of chicken heart proteins. The integration of differential equation made it possible to describe the kinetics of the proteolysis in terms of substrate concentration, degree of proteolysis and reaction time. The kinetics of proteolysis does not obey the MICHAELIS‐MENTEN law. The proposed way for mathematical modelling permits the optimization by productivity.
Qualitätsveränderungen während der Lagerung von Gemüsebohnen (Phaseolus vulgaris L. var. nanus Juslen. Aschers.) 3. Mitt Sensorische Qualität
Authors: Böttcher H.
Published: November 2006

Während der Lagerung von handgeernteten Gemüsebohnen bei verschiedenen Lagertemperaturen (0, 4, 12 bis 15, 18 und 24°C) treten bei den einzelnen Merkmalen der sensorischen Qualität, die über die Herstellung von Gefrierkonserven bestimmt worden sind, meist lineare Veränderungen mit der Lagerdauer (x) ein: y = α0 − β1 x. Sie beruhen auf einer Abflachung der produktspezifischen Aromastoffe und der Herausbildung unerwünschter, biochemisch bedingter Veränderungen in den pflanzlichen Geweben. Die Merkmale Geruch und Geschmack zeigen jeweils den stärksten Qualitätsrückgang mit 0,16 Wertnote/Tag bei 4°C und 0,25 bzw. 0,30 Wertnote/Tag für 18°C. Die aus den sensorischen Merkmalen berechnete Haltbarkeitsfunktion ist nicht so kritisch wie die aus der äußeren Qualität bestimmte.
Tierexperimentell‐toxikologische Untersuchungen von Proteinisolaten aus Sonnenblumensamen
Authors: Hoernicke E. , Lewerenz H.‐J. , Mieth G.
Published: November 2006

In subchronischen Fütterungsversuchen (90‐Tage‐Test) wurde an männlichen und weiblichen Ratten die toxikologische Unbedenklichkeit nach verschiedenen Verfahren gewonnener Sonnenblumen‐Proteinisolate (SPI) geprüft. Als Kriterien der Tests dienten der Allgemeinzustand der Tiere, die Futteraufnahme und ‐verwertung, der Blutstatus, die Nierenfunktion und Harnanalysen, die Bestimmung der Serumbestandteile, insbesondere der Enzymaktivitäten, die Organmassevergleiche sowie die makroskopische und mikroskopische Pathologie. Im Vergleich zwischen Kontroll‐ und Versuchsgruppen mit abgestuftem Ersatz des Futterproteins bis zu 75% durch SPI konnten bis zu einer durchschnittlichen täglichen Aufnahme von 13 g SPI/kg Körpermasse an den Versuchstieren keine toxischen morphologischen und funktionellen Veränderungen ermittelt werden, die auf die SPI‐Aufnahme zurückzuführen wären. Diese Bewertung erstreckt sich weitgehend auch auf die getesteten SPI‐Varianten.
Application of glycerol to freezing bovine pancreas. Part 1. Effect of cryoprotector on activity of certain enzymes in frozen minced pancreas
Authors: Hajduk E. , Fik M.
Published: November 2006

Effects of different concentrations of glycerol on the activity of amylase, lipase, and proteases in frozen minced pancreas were studied. A 15% glycerol addition was found to decrease the proteolytic enzyme activity and to increase the activity of amylase. Moreover, accelerated freezing was shown to enhance the activity of all the enzymes studied.
Use of oyster shell as calcium supplement. Part 2. An assessment of the responses of hepatic and serum enzymes, relative organ weights, and bone mineralization in the broiler chicken fed gossypol‐containing cottonseed cake supplemented with oyster shell
Authors: Aletor V. A. , Aturamu O. A.
Published: November 2006

The role of oyster shell as calcium supplement in the utilization of gossypol‐containing cottonseed cake (CSC) was assessed using Hypeco broiler chickens. The results showed that of the organ measured, only the relative weight of the spleen was significantly (P < 0.05) decreased by oyster shell supplementation in the CSC diets. Spleen weight correlated negatively (r = −0.45) with dietary calcium. Alkaline phosphatase activity in the liver was significantly (P < 0.05) increased due to the levels of oyster shell supplemented while the activities of serum and liver alanine aminotransferase and aspartate aminotransferase were not significantly influenced.

The results also showed that although oyster shell supplementation generally increased alkaline phosphatase activity, bone mineralization was relatively uninfluenced as judged by the low coefficients of variation (CV) of 3.14–3.61% and 3.39–4.82% for calcium and phosphorus content in the femur and tibia respectively.
Dissimilation of organic acids by dairy lactic acid bacteria
Authors: Hegazi F. Z. , Abo‐Elnaga I. G.
Published: November 2006

One hundred and eleven different strains of lactic acid bacteria, belonging to the genera Leuconostoc, Streptococcus and Lactobacillus, were examined for their ability to degrade 10 organic acids by detecting CO2 production, using the conventional Durham tube method. All the strains did not break down succinate, glutarate, 2‐oxoglutarate, or mucate. Malate, fumarate, citrate, gluconate, tartrate and pyruvate were variably attacked. A malo‐lactic fermentation was brought about by two thirds of S. cremoris and S. lactis strains as well as L. casei but not by L. buchneri or L. brevis. One third of the lactic streptococci examined, i.e. S. cremoris AM2, ML8 and SK11 were capable of diacetyl production. They required glucose for cleavage of citrate, whereas Leuconostoc citrovorum and S.faecalis did not. S. cremoris differed from S. lactis in not producing CO2 from gluconate. From all the lactic acid bacteria examined, only L. plantarum dissimilated tartrate. Production of acetoin and diacetyl is a more reliable evidence for assessing the degradation of pyruvate, compared to detection of evolved CO2. Facultatively heterofermentative lactobacilli and Leuconostoc citrovorum produced acetoin and diacetyl from pyruvate, whereas the obligately heterofermentative lactobacilli did not, a character that would be of taxonomic value. Glucose fermented by both the facultatively and obligately heterofermentative lactobacilli did not prove to be a metabolic source of acetoin and diacetyl. The facultative heterofermenters degraded pyruvate in the presence of glucose with lactate as the major product together with a mean of acetate of 4.1%, ethanol of 7.9%, acetoin of 1.7% and diacetyl of 2.6% yield on a molar basis after 60 days at 30°C. L. brevis produced acetate and lactate. The role of S. cremoris and the facultatively and obligately heterofermentative lactobacilli in flavour development during the ripening of many cheese varieties has been confirmed.
Modern immunoassays in meat‐product analysis
Authors: Fukal L.
Published: November 2006

The increased regulation of foodstuffs in modern society requires analytical methods which are easy to perform, sensitive, specific and relatively inexpensive. The basic antigen‐antibody reaction provides means for very specific analytical procedures. Immunoassays are powerful analytical tools that permit the specific and rapid detection or measurement of antigens and haptens to which antibodies can be produced. Sensitive recognition of the interaction is made possible by labelling the analyte or antibody, mainly with radioisotope (RIA) and enzyme (ELISA). Wide applications of these modern immunoassays to food analysis began about 1980.

The paper reviews investigations, where various types of RIA and ELISA were developed for the use in meat product analysis. Detection and determination of various meat species, non‐meat proteins; microorganisms and bacterial toxins, drugs, anabolic hormones, pesticides, mycotoxins, and other contaminants in meat and meat products by the means of immunoassays is described. Now, the commercial kits are available for most of these compounds. They make possible to perform analysis in different laboratories under standard conditions. The reason of an enthusiasmic acceptance of this technology is related to its inherent specificity, high sensitivity, and the facility of application. In fact, immunoassays compete with other analytical technics. They have the advantage of economy when screening large numbers of samples.
Influence of the concentration of the main organic acids of wine on the cations adsorption of bentonites in synthetic wine
Authors: Arvanitoyannis I. , Fronimos P. , Psomiadou E.
Published: November 2006

The influence of concentration of the main organic acids such as tartaric, malic, citric, and succinic acids on the cation content (Ca, Mg, Fe, Cu, Zn and Mn) during treatment with optimum mass of two bentonites (Calcium and Calcium‐Sodium) in synthetic wine, is studied. Only in case of succinic acid, a lower Fe absorption is observed, probably due to its weaker acid character, compared to other acids.
The influence of selected technological processes on the improvement of rapeseed meal and fluor feed quality. Part 1. The influence of hydrothermal treatment and ethanol extraction on chemical composition of rapeseed products
Authors: Kozlowska H. , Zadernowski R. , Nowak H. , Piskula M.
Published: November 2006

As the majority of noxious compounds in rapeseed, e. g. glucosinolates, phenolic compounds and other non‐investigated ones, are well soluble in alcohol, an attampt was made to establish to which extent it is possible to eliminate these compounds from flour with 80 % alcohol and to which extent hydrothermal treatment increases the extraction efficiency. The results of the chemical composition of the differently treated products from the double‐improved Jantar variety show, that hydrothermal treatment of whole seeds results in easier extraction of the major part of the compounds analysed. But under the influence of the applied processes protein denaturation changes may take place.
Selected functional properties of detoxified rapeseed protein preparations effected by phytic acid
Authors: Kroll J.
Published: November 2006

Detoxified rapeseed protein preparations with high protein content (>90 %) produced by extraction, ultra‐and diafiltration, have a very good solubility and excellent foaming properties (better than egg white). The emulsifying properties (emulsifying activity and emulsion stability) are moderate. The N‐solubility profile of these preparations (albumin and globulin mixing) has been influenced by phytic acid (PA). It is possible to observe a shift of the isoelectric range to lower pH‐values and parallel a decrease of solubility if the amount of PA (3, 5, 10 %) is increased. The foaming properties have also been dependent on the PA content. A higher concentration of PA (3, 5, 10 %) causes a decrease in the foaming activity. The results have been discussed concerning the interactions between PA and proteins.
Metabolic effects of licorice roots (Glycyrrhiza glabra) on lipid distribution pattern, liver and renal functions of albino rats
Authors: Sitohy M. Z. , El‐Massry R. A. , El‐Saadany S. S. , Labib S. M.
Published: November 2006

The biochemical activity of licorice roots was investigated by administrating it to hypercholesterolaemic rats at two different doses. High cholesterol level in the serum and most organs of hypercholesterolaemic rats was accompanied by high levels of triglycerides and total lipids but low one of phospholipids. The hypocholesterolaemic action of licorice roots was accompanied by hypolipaemic action but higher level of phospholipids in the rat serum and most organs.

The results showed that while the high cholesterol level in the rat serum has impairing effects on liver and renal functions, the licorice administered to these rats has a counteracting action i.e. it can improve the impaired function of both liver and kidney, It has also a hypoglycaemic action.
Effect of osmotic shock on osmotolerant yeasts
Authors: Bhajekar Deepa , Kulkarni P. R.
Published: November 2006

Shock exposure of osmotolerant yeasts Debaryomyces hansenii 3339, Zygosaccharomyces mellis 3296 and Kloeckera antilarrum 3046 to solutions of sucrose at water activity (Aw) values between 0.99 and 0.88 was found to cause a great decrease in cell volume but an increase in heat resistance. For Debaryomyces hansenii the cell volume decreased from 28 μm3 to 4 μm3 and it could withstand a temperature of 65°C for over 20 min. Zygosaccharomyces mellis and Kloeckera antilarrum showed a decrease in cell volume from 31 μm3 to 3 μm3 and 4 μm3 respectively and both survived a heat treatment of 75°C for over 30 min.
Rückstände von Organochlorpestiziden, PCB's und Chlorphenolen in Fischen aus Teichwirtschaften und fischwirtschaftlich genutzten Gewässern im Gebiet um Frankfurt (Oder)
Authors: Hollstein A.
Published: November 2006

Fische aus Teichwirtschaften und fischwirtschaftlich genutzten Gewässern im Gebiet des ehemaligen Bezirkes Frankfurt (Oder) wurden auf den Gehalt an Organochlorpestiziden (HCB, Aldrin, HCH‐Isomere, DDD, DDE, DDT, Endrin, Toxaphen und Dieldrin), PCB's und Penta‐ und Tetrachlorphenol untersucht. Dabei wurden Säureaufschluß‐ und Extraktionsverfahren zur Aufarbeitung verglichen und die Möglichkeiten einer Simultanbestimmung von chlorierten Kohlenwasserstoffen, PCB's und Chlorphenolen mittels saurer Kieselgelextraktion in Fischen aufgezeigt. Die Identifizierung und Quantifizierung der zu bestimmenden Stoffe erfolgte gaschromatographisch mittels ECD auf zwei gepackten und einer fused silica Kapillar‐Trennsäule. Die Ausschöpfung der gültigen Höchstmengen liegt für die untersuchten Fischproben, mit Ausnahme von Toxaphen und Pentachlorphenol, bei 2‐10 %. Für Toxaphen und Pentachlorphenol werden zu 50 % Gehalte in Grenzwertnähe ermittelt. Der Einsatz beider Wirkstoffe auf dem Gebiet der ehemaligen DDR noch bis zu diesem Jahr muß als Ursache dafür angesehen werden. Die ermittelten Kontaminationswerte für Organochlorpestizide und PCB sind mit den neuesten Ergebnissen von Fischuntersuchungen im Gebiet der alten Bundesländer vergleichbar.
The effect of Sammo administration on some fundamental enzymes of pentose phosphat pathway and energy metabolites of alloxanized rats
Authors: Abdel‐Rahim E. A. , El‐Saadany S. S. , Abo‐Eytta A. M. , Wasi M. M.
Published: November 2006

Sammo plant which is traditionally used in Egypt for the treatment of diabetes mellitus, was administered at low and high levels (4% and 8% respectively at the expense of starch) to adult male alloxanized albino rats, to study its effect on energy metabolism. Adenosine‐5‐triphosphate (ATP) in the brain (B), liver (L) and kidneys (K) organs of alloxanized rats was significantly lowered compared with the negative control. On the other hand, adenosine‐5‐diphosphate (ADP) and adenosine‐5‐monophosphate (AMP) contents in the same organs were elevated markedly. In this connection myokinase activity in cytoplasmic and mitochondrial fractions of B, L and K organs was stimulated at control. Also, the activities of some fundamental enzymes of the oxidative pentose phosphate pathway i.e. glucose‐6‐phosphate dehydrogenase (G‐6‐PD) and 6‐phospho‐gluconate dehydrogenase (6‐PGD) in cytoplasmic and mitochondrial fractions of the same organs were markedly increased.

Administration of Sammo at low and high levels reduced the consumption of ATP in B, L and K organs relative to positive control. Whereas, ADP and AMP contents were relatively reduced. Also, myokinase activity in the same organs were relatively inhibited. The activity of G‐6‐PD and 6‐PGD in cytoplasmic and mitochondrial fractions of the same organs were also decreased relative to the positive control.
Ein Überblick zur digitalen Bildverarbeitung in der Lebensmittelwissenschaft 1. Mitt. Bestimmung geometrischer Merkmale an isolierten Objekten
Authors: Fromhold‐Treu I. , Kozerke W.
Published: November 2006

Ziel dieser Artikelserie ist eine Zusammenfassung von Verfahren und Methoden der digitalen Bildverarbeitung unter dem Blickwinkel ihrer speziellen Anwendung in der Lebensmittel‐ und Ernährungswissenschaft. Nach einer kurzen Einführung in die Grundlagen der digitalen Bildverarbeitung werden effektive Verfahren zur Erkennung isolierter Objekte in Binärbildern behandelt. Außerdem werden für diese Objekte geometrische Merkmale definiert.
Ein Überblick zur digitalen Bildverarbeitung in der Lebensmittelwissenschaft 2. Mitt. Rekonstruktion von Konturen isolierter Objekte
Authors: Kozerke W. , Fromhold‐Treu I.
Published: November 2006

Die Konturen von Objekten in digitalen Bildern können aus verschiedenen Gründen gestört sein, so daß die Objekte nicht vollständig erkannt werden können. In solchen Fällen werden Methoden zur Objektrekonstruktion benötigt. Es werden die Approximation der Objekte durch Ellipsen, Spline‐Funktionen und konvexe Hüllpolygone behandelt. Auch durch Dilatation und Erosion ist eine Objektrekonstruktion möglich. Schließlich wird eine Methode von Toussaint und Donaldson zum Schließen kleinerer Lücken in Konturen beschrieben.