Abstract  Two combinations of hurdles, 2.0% lactate+0.5% acetate or 2.0% lactate+0.25 % glucono-delta-lactone (GdL), were both found to prevent growth of Listeria monocytogenes inoculated onto sliced saveloys manufactured with 60 or 150 ppm nitrite. The saveloys were packed in modified atmosphere (80% N(2)/20% CO(2)) using a film with low oxygen transmission rate (0.45 cm(3)/m(2)/atm/24 h) and stored at 5 or 10°C for up to 4 weeks. Changes in red colour (measured as Minolta a-values) and lipid oxidation [measured as thiobarbituric acid reactive substances (TBARS)] were low during storage at 5°C and unaffected by the storage conditions (±light). However, 2.0% lactate+0.25% GdL improved oxidative stability and led to significantly lower TBARS and significantly higher a-values. Levels of nitrosamines were low with values near the detection level. Although observed differences were small, members of a trained sensory panel were able to distinguish saveloys containing chemical hurdles from saveloys without. Judges most often mentioned flavour as being the deviating descriptor.

Abstract  Despite the increasing clinical use of topical platelet-rich plasma (PRP) to enhance tissue healing and regeneration, there is no properly standardized method of autologous PRP gel preparation. This study examined the effect of the centrifugation time and gravitational force (g) on the platelet recovery ratio of PRP and determined the most effective centrifugation conditions for preparing PRP. Two-step centrifugations for preparing PRP were used in 39 subjects who had consented prior to the study's start. The separating centrifugation (Step 1, used to separate whole blood into its two main components: red blood cells and plasma) was tested from 500g to 1900g at 200g increments for 5 minutes (min), and from 100g to 1300g at 200g increments for 10 minutes. After separating centrifugation, upper plasma layer was transferred to another plain tube for the condensation centrifugation and remaining lower cell layer was discarded. The condensation centrifugation (Step 2, used to condense the platelets in the separated plasma) was tested at 1000g for 15 min, 1500g for 15 min, 2000g for 5 min and 3000g for 5 min, additionally at 1000g for 10 min and 1500g for 10 min. Platelet gelation was induced by adding 10% calcium gluconate to final PRP with volume ratio of 1:10. The optimal separating centrifugation conditions were followed by 900g for 5 minutes and the condensation conditions were followed by 1500g for 15 minutes, of which recovery ratios were 92.0 ± 3.1% and 84.3 ± 10.0%, respectively.

Abstract  A glycoside hydrolase characterized by beta-fucosidase (EC 3.2.1.38) and beta-glucosidase (EC 3.2.1.21) activities was purified from the culture medium of the anaerobic ruminal phycomycete Neocallimastix frontalis grown on 0.5% Avicel. The enzyme had a molecular mass of 120 kilodaltons and a pI of 3.85. Optimal activity against p-nitrophenyl-beta-d-fucoside and p-nitrophenyl-beta-D-glucoside occurred at pH 6.0 and 50 degrees C. The beta-fucosidase and beta-glucosidase activities were stable from pH 6.0 to pH 7.8 and up to 40 degrees C. They were both inhibited by gluconolactone, sodium dodecyl sulfate, p-chloromercuribenzoate, and Hg cation. The enzyme had K(m)s of 0.26 mg/ml for p-nitrophenyl-beta-d-fucoside and 0.08 mg/ml for p-nitrophenyl-beta-d-glucoside. The purified protein also had low beta-galactosidase activity.

Abstract  Inhibition of Trichoderma reesei cellulase by sugars (glucose, delta-gluconolactone, and cellobiose) and solvents (ethanol, butanol, and acetone) was studied using cellulose azure. Glucose, cellobiose, ethanol, and butanol were noncompetitive inhibitors, delta-gluconolactone was a mixed inhibitor, and acetone was a noncompetitive activator. Converting cellobiose to glucose reduces the effective inhibitor binding constant by 6 times and converting cellobiose to ethanol reduces it by 16 times.

Abstract  A new metabolic pathway has been created in the microorganism Erwinia herbicola that gives it the ability to produce 2-keto-L-gulonic acid, an important intermediate in the synthesis of L-ascorbic acid. Initially, a Corynebacterium enzyme that could stereoselectively reduce 2,5-diketo-D-gluconic acid to 2-keto-L-gulonic acid was identified and purified. DNA probes based on amino acid sequence information from 2,5-diketo-D-gluconic acid reductase were then used to isolate the gene for this enzyme from a Corynebacterium genomic library. The 2,5-diketo-D-gluconic acid reductase coding region was fused to the Escherichia coli trp promoter and a synthetic ribosome binding site and was then introduced into E. herbicola on a multicopy plasmid. Erwinia herbicola naturally produces 2,5-diketo-D-gluconic acid via glucose oxidation, and when recombinant cells expressing the plasmid-encoded reductase were grown in the presence of glucose, 2-keto-L-gulonic acid was made and released into the culture medium. The data demonstrate the feasibility of creating novel in vivo routes for the synthesis of important specialty chemicals by combining useful metabolic traits from diverse sources in a single organism.

Abstract  A new medium, designated TMYGP broth, was developed that allowed the honeybee pathogen Bacillus larvae NRRL B-3650 to produce up to 5 x 10 spores per ml of culture (microscopic count). This species normally sporulates poorly, if at all, in artificial broth media. An aeration rate lower than that normally used to cultivate other Bacillus species was required for sporulation. During the exponential growth phase, acids were produced by catabolism of yeast extract components, causing a decrease in pH of the medium. Thereafter, the pH began to increase, probably because of derepression of the citric acid cycle and consumption of the acids. Only after this time did usage of glucose from the medium occur. Thus, glucose usage seems to be regulated by catabolite repression. The presence of glucose was needed for one or more of the later events of sporulation. Of many substances tested, only gluconic acid and glucosamine partially substituted for glucose as a requirement for sporulation. Pyruvate was also required for good sporulation. It was metabolized during the late-exponential phase of growth.

Abstract  The major water-soluble constituent of the defensive secretion of Eurycotis decipiens was identified as gluconic acid, isolated in the form of calcium D-gluconate. The acid, in equilibrium with its lactones, is present in unusually high concentration.

Abstract  The fact that fungal glucans will stimulate soybeans to accumulate phytoalexins prompted an investigation of soybean cell beta-1,3-glucanases and beta-glucosidases, as well as the ability of these enzymes to hydrolyze the fungal glucans. Several beta-1,3-glucanases and beta-glucosidases can be solubilized from the walls of suspension-cultured soybean cells by treatment with 1.0 molar sodium acetate buffer. An enzyme, which has been termed beta-glucosylase I, is the dominant beta-1,3-glucanase in the cell wall extracts. Utilizing CM-Sephadex chromatography, hydroxylapatite chromatography, and affinity chromatography, beta-glucosylase I has been purified 71-fold, with 39% recovery, from the mixture of cell wall enzymes. The affinity chromatography column material was prepared by covalently attaching p-aminophenyl-1-beta-d-glucopyranoside, an analog of a beta-glucosylase I substrate, to Sepharose. beta-Glucosylase I, purified by this procedure, yields a single band on isoelectric focusing gels (pH 8.9). However, the purified beta-glucosylase I yields a darkly-staining protein band at an apparent molecular weight of 69,000 and several lightly-staining protein bands in sodium dodecyl sulfate polyacrylamide gels. Additional purification procedures fail to remove these lightly-staining protein bands.beta-Glucosylase I will hydrolyze the beta-glucan substrates, laminarin (3-linked) and lichenan (3- and 4-linked), and therefore, possesses beta-glucanase activity. Studies of the progressive hydrolysis of laminarin by beta-glucosylase I demonstrate that the enzyme hydrolyzes polysaccharide substrates in an exo manner. beta-Glucosylase I will also hydrolyze a variety of low molecular weight beta-glucosides including various beta-linked diglucosides. Thus, beta-glucosylase I also possesses beta-glucosidase activity.Several lines of evidence are presented that the beta-glucanase and the beta-glucosidase activities exhibited by purified beta-glucosylase I preparations are catalyzed by the same enzyme. This evidence includes inhibition studies which indicate that the beta-glucanase and the beta-glucosidase activities of beta-glucosylase I are catalyzed at the same active site. beta-Glucosylase I will also catalyze glucosyl transfer. This catalytic activity is responsible for the observed ability of the enzyme to synthesize di- and trisaccharides from laminarin. The disaccharides formed by beta-glucosylase I-catalyzed transglucosylation are the beta-anomers of the 6-, 4-, 3-, and 2-linked diglucosides in the relative proportions of 10:1:1:1. The ability of beta-glucosylase I to catalyze glucosyl transfer indicates that beta-glucosylase I is biochemically more similar to previously studied beta-glucosidases than to beta-glucanases. This conclusion is supported by the observation that beta-glucosylase I is strongly inhibited by 1,5-d-gluconolactone, an inhibitor of beta-glucosidases but not of beta-glucanases.

Abstract  Gold (Au) catalysts have been rarely investigated for the oxidation of glucose in the absence of a base. These conditions are critical, however, to enable the sequential one-pot combination of cellulose hydrolysis and glucose oxidation. Here we evaluate the catalytic performance and stability of Au nanoparticles supported on metal oxides for the oxidation of glucose to gluconic acid under unadjusted pH and acidic conditions. The study provides insights into the deactivation of the catalysts caused by leaching and hydrothermal sintering of Au nanoparticles, as well as by adsorption of reactive species. We found that lowering the surface density of Au on metal oxides decreases the sintering rate of the Au nanoparticles and hence enhances the stability and activity of the catalysts.

Abstract  The effects of reverse osmosis (RO) membrane type on the rejection efficiency of boric acid, monoborate and boron complexes with D-mannitol, sodium D-gluconate and N-methyl D-glucamine was revealed. The membranes examined included: XLE, TW-30, BW-30 and SW-30, supplied by DOW (TM) FILMTEC (TM). The mass transport coefficients: permeability and reflection coefficient were determined for each species in boric acid-polyol aqueous system. The influence of the membrane type upon these coefficients was evaluated and quantitative, comparative analysis of the efficacy of boron rejection at varying permeate flux, the feedwater boron content, the alcohol/boron molar ratio and the pH was conducted. It was found that boron rejection in the above systems was determined by the extent of boric acid transport, even when boric acid constituted only a minor component of the feedwater. At high permeate flux the effectiveness in boric acid rejection decreased in the following descending membrane order: SW-30 > BW-30 > TW-30 > XLE. The results presented here enable the selection of the best membrane, the most suitable operating conditions for boron separation by RO in the presence or absence of polyols, and for quantitative prediction of the efficiency of boron removal with various RO membranes. (C) 2013 Elsevier B.V. All rights reserved.

Abstract  Screen-printed carbon electrodes have been modified with tetrathiafulvalene and sulfite oxidase enzyme for the sensitive and selective detection of sulfite. Amperometric experimental conditions were optimized taking into account the importance of quantifying sulfite in wine samples and the inherent complexity of these samples, particularly red wine. The biosensor responds to sulfite giving a cathodic current (at +200 mV vs screen-printed Ag/AgCl electrode and pH 6) in a wide concentration range, with a capability of detection of 6 μM (α=β=0.05) at 60°C. The method has been applied to the determination of sulfite in white and red samples, with averages recoveries of 101.5% to 101.8%, respectively.

Abstract  An emerging approach toward development of injectable, self-setting, and fully biodegradable bone substitutes involves the combination of injectable hydrogel matrices with a dispersed phase consisting of nanosized calcium phosphate particles. Here, novel injectable composites for bone regeneration have been developed based on the combination of ultrapure alginate as the matrix phase, crystalline CaP [monetite and poorly crystalline hydroxyapatite (HA)] powders as both a dispersed mineral phase and a source of calcium for cross-linking alginate, glucono-delta-lactone (GDL) as acidifier and glycerol as both plasticizer and temporary sequestrant. The composites were maximized with respect to CaP content to obtain the highest amount of osteoconductive filler. The viscoelastic and physicochemical properties of the precursor compounds and composites were analyzed using rheometry, elemental analysis (for calcium release and uptake), acidity [by measuring pH in simulated body fluid (SBF)], general biocompatibility (subcutaneous implantation in rabbits), and osteocompatibility (implantation in femoral condyle bone defect of rabbits). The gelation of the resulting composites could be controlled from seconds to tens of minutes by varying the solubility of the CaP phase (HA vs. monetite) or amount of GDL. All composites mineralized extensively in SBF for up to 11 days. In vivo, the composites also disintegrated upon implantation in subcutaneous or bone tissue, leaving behind less degradable but osteoconductive CaP particles. Although the composites need to be optimized with respect to the available amount of calcium for cross-linking of alginate, the beneficial bone response as observed in the in vivo studies render these gels promising for minimally invasive applications as bone-filling material.

Abstract  The synthesis and structure-activity relationship (SAR) of thiophene-C-glucosides have been explored, and the human sodium-dependent glucose cotransporter 2 (hSGLT2) inhibitory activities and rat urinary glucose excretion (UGE) effects of 3a-f were evaluated. As a result, they showed good hSGLT2 inhibitory activities and rat UGE effects. In particular, the chlorothiophene derivative 3f showed remarkable inhibitory activity against hSGLT2.

Abstract  [reaction: see text] Glucal 3-carbamates 1 and 7 underwent oxidative cyclization with iodobenzene diacetate or iodosobenzene in the presence of Rh2(OAc)4, providing mannosamine 2-N,3-O-oxazolidinones. With iodosobenzene, incorporation of 4-penten-1-ol provided a readily separable anomeric mixture of n-pentenyl glycosides, with the anomers exhibiting pronounced differences in reactivity as glycosyl donors. N-acylation of the sugar oxazolidinones led to alpha-selective glycosyl donors for the elaboration of various 2-mannosamine frameworks. Alternatively, the anomeric n-pentenyl glycosides of N-Cbz 2-mannosamine oxazolidinones were converted separately to oxazolidinone-opened derivatives 28alpha and 28beta. These served as stereoconvergent glycosyl donors, and the alpha-linked products were readily advanced to a variety of N-acetylmannosamine (ManNAc) frameworks, using an intramolecular O-->N acetyl transfer as the final step.

Abstract  A multifunctional mediating system for bioelectrocatalytic oxidation of glucose is described. It comprises a conducting polymer, poly(3,4-ethylenodioxythiophene), carbon nanotubes modified with 4-(pyrrole-1-yl) benzoic acid that provide carboxyl groups that aid immobilization of glucose oxidase in a conductive three-dimensional network, tetrathiafulvalene that mediates electron exchange with the enzyme. This composite produces a system that is capable of effective oxidation of glucose to gluconic acid at pH7. The current is concentration dependent to at least 60mM and maintains 77% of initial response for 35 days. Data supporting the utility of this system for electrochemical sensing and biofuel cell technology are presented.

Abstract  All presently used batteries contain reactive, corrosive or toxic components and require strong cases, usually made of steel. As a battery is miniaturized, the required case dominates its size. Hence, the smallest manufactured batteries are about 50 mm3 in size, much larger then the integrated circuits or sensors of functional analytical packages, as exemplified by implantable glucose sensors for diabetes management. The status of the miniaturization of the power sources of such implantable packages is reviewed. Three microcells, consisting only of potentially harmless subcutaneously implantable anodes and cathodes, are considered. Because their electrolyte would be the subcutaneous interstitial fluid, the cells do not have a case. One potentially implantable cell has a miniature Nafion-coated Zn anode and a biocompatible hydrogel-shielded Ag/AgCl cathode. The core innovation on which the cell is based is the growth of a hopeite-phase Zn2+ conducting solid electrolyte film on the discharging anode. The film blocks the transport of O2 to the Zn, preventing its corrosion, while allowing the necessary transport of Zn2+. The second cell, with the same anode, would have a bioinert hydrogel-shielded wired bilirubin oxidase-coated carbon cathode, on which O2 dissolved in the subcutaneous fluid would be electroreduced to water. In the third cell, the glucose of the subcutaneous interstitial would be electrooxidized to gluconolactone at an implanted wired glucose anode, similar to that tested now for continuous glucose monitoring in diabetic people, and O2 in the subcutaneous fluid would be electroreduced to water on its wired bilirubin oxidase cathode.

Abstract  In this paper, the influence of carbon and silica particle slurry concentration up to 20 g/l (4 vol%) on regime transition, gas hold-up, and volumetric mass transfer coefficient is studied in a 2-dimensional slurry bubble column. From high speed video image analysis, the average large bubble diameter, the frequency of occurrence of large bubbles, the gas-liquid interfacial area, and the large bubble hold-up are obtained. The liquid side mass transfer coefficient is calculated from the volumetric mass transfer coefficient and the gas-liquid interfacial area. The lyophilic silica particles are rendered lyophobic by a methylation process to study the influence of particle wettability. The influence of organic electrolyte (sodium gluconate) and the combination of electrolyte and particles is also studied. It is found that lyophilic silica, lyophobic silica, and lyophobic carbon particles at concentrations larger than 2 g/l (0.4 vol%) decrease the gas hold-up and shift the regime transition point (where the first large bubbles appear) to a lower gas velocity. The volumetric mass transfer coefficient increases with gas velocity, increases with electrolyte concentration, decreases with slurry concentration, and is higher for lyophobic particles. The liquid side mass transfer coefficient increases with gas velocity, bubble diameter, and is higher for lyophobic particles. A correlation for the mass transfer coefficient based on dimensionless numbers is proposed for the heterogeneous regime.

Abstract  We originally identified senescence marker protein 30 (SMP30) as a distinctive protein whose expression decreases in an androgen-independent manner with aging. Here, we report its sequence homology found in two kinds of bacterial gluconolactonases (GNLs) by using the blast search. Then, through a biochemical study, we identify SMP30 as the lactone-hydrolyzing enzyme GNL of animal species. SMP30 purified from the rat liver had lactonase activity toward various aldonolactones, such as d- and l-glucono-delta-lactone, d- and l-gulono-gamma-lactone, and d- and l-galactono-gamma-lactone, with a requirement for Zn(2+) or Mn(2+) as a cofactor. Furthermore, in SMP30 knockout mice, no GNL activity was detectable in the liver. Thus, we conclude that SMP30 is a unique GNL in the liver. The lactonase reaction with l-gulono-gamma-lactone is the penultimate step in l-ascorbic acid (AA) biosynthesis, and the essential role of SMP30 in this synthetic process was verified here by a nutritional study using SMP30 knockout mice. These knockout mice (n = 6), fed a vitamin C-deficient diet, did not thrive; i.e., they displayed symptoms of scurvy such as bone fracture and rachitic rosary and then died by 135 days after the start of receiving the deficient diet. The AA levels in their livers and kidneys at the time of death were <1.6% of those in WT control mice. In addition, by using the SMP30 knockout mouse, we demonstrate that the alternative pathway of AA synthesis involving d-glucurono-gamma-lactone operates in vivo, although its flux is fairly small.

Abstract  Kinetic investigation of oxidation of glucose and fructose, by alkaline solution of N-chloronicotinamide (NCN) has been carried out in the temperature range 308-328 K. The reaction shows first order in [alkali] and [substrate] and zero order in oxidant. Addition of nicotinamide (NA) has no effect. Increase in ionic strength of the medium does not change the rate. Effect of temperature on the rate of oxidation has been followed to show the validity of the Arrhenius equation and various activation parameters have been computed. The stoichiometry of the reaction was found to be 1:1. 1,2-enediol is found to be the reactive intermediate. Gluconic acid and formic acid are the products of oxidation for glucose and fructose, respectively.

Abstract  Allylamides of gluconic acid were synthesized by the reaction of allylamine with lactones using dimethyl formamide as a solvent. In this reaction, hydroxyl groups were protected by trimethylsilyl groups via three different pathways that connect sugar units onto the polysiloxane chains. A series of well-defined polysiloxanes with pendent sugar units were prepared by hydrosilation of the trimethylsilyl-protected allylamides with hydric polysiloxanes in the presence of the Platinum dioxide as a catalyst. The catalytic activity and selectivity were discussed in detail. All products were characterized by FT-IR, H-1 NMR, and C-13 NMR spectroscopy, respectively. Furthermore, the shapes of molecular aggregates of target polymers in water were studied by transmission electron microscopy, which reveals that the transitions of micelles-morphologies from spheres to vesicles can be controlled by adjusting hydrogen content of primary materials or by changing initial solvents. (c) 2006 Elsevier Ltd. All rights reserved.

Abstract  Nano- and micro-sized LiFePO4 powders were synthesized by a sodium gluconate (C6H11NaO7)-assisted hydrothermal synthesis method at 220 degrees C for 10 h with pH = 2-7. The resulting powders were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometer (EDS). The obtained data showed that the pH of synthesis solution played a key role in the formation of the LiFePO4 powders with different morphologies, such as ball-like microspheres, irregular microspheres with the agglomerated rods and particles, sphere-like nanoparticles and nano-ellipsoids. The results from electrochemical performance measurements revealed that the charge-discharge cycling characteristics of the samples were strongly dependent on their morphologies. In particular, the ellipsoidal LiFePO4 nanoparticles with the average size of 70-90 nm showed the highest initial discharge capacity of 150 mA h g(-1) at 0.1 C rate, and cycling stability of the ellipsoidal LiFePO4 nanoparticles was optimum among all the samples prepared due to their dual advantages of high tap density and good diffusion property. The present study offers a simple morphology-controllable route, without carbon coating or doping with supervalent cations, to synthesize and to design high performance cathode materials for lithium-ion batteries. (C) 2013 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.

Abstract  The real-time dynamic heterogeneity of the gelation process of the amino acid derivative Fmoc-tyrosine (Fmoc-Y) is studied using particle tracking microrheology. To trigger gelation, glucono-δ-lactone (GdL) is added, which gradually lowers the p H over several hours. The onset of self-assembly in the system is signified by a sharp drop in the mean-squared displacement of embedded particles, a phenomenon that is found to correlate with the p H of the system reaching the pK(a) of Fmoc-Y. The gel point is identified and found to be dependent on the GdL concentration. Analysis of embedded probe particle dynamics allows the heterogeneity of the sample to be quantified, using three metrics: the heterogeneity ratio (HR), the non-Gaussian parameter of the van Hove correlation function (N and the bin distribution of the mean-squared displacement (MSD) of single particles (f(z)). Results from the three techniques are found to be approximately comparable, with increases in heterogeneity observed in all samples for incubation times t(w) = 0-3 hours. The final heterogeneity in all samples is found to be remarkably low compared to other systems previously reported in the literature.

Abstract  Tetranuclear copper(II) complexes containing alpha-D-glucose-1-phosphate (alpha-D-Glc-1P), [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(bpy)4(H2O)2]X3 [X = NO3 (1a), Cl (1b), Br (1c)], and [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(phen)4(H2O)2](NO3)3 (2) were prepared by reacting the copper(II) salt with Na2[alpha-D-Glc-1P] in the presence of diimine ancillary ligands, and the structure of 2 was characterized by X-ray crystallography to comprise four {Cu(phen)}2+ fragments connected by the two sugar phosphate dianions in 1,3-O,O' and 1,1-O mu4-bridging fashion as well as a mu-hydroxo anion. The crystal structure of 2 involves two chemically independent complex cations in which the C2 enantiomeric structure for the trapezoidal tetracopper(II) framework is switched according to the orientation of the alpha-D-glucopyranosyl moieties. Temperature-dependent magnetic susceptibility data of 1a indicated that antiferromagnetic spin coupling is operative between the two metal ions joined by the hydroxo bridge (J = -52 cm(-1)) while antiferromagnetic interaction through the Cu-O-Cu sugar phosphate bridges is weak (J = -13 cm(-1)). Complex 1a readily reacted with carboxylic acids to afford the tetranuclear copper(II) complexes, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-CA)2(bpy)4](NO3)2 [CA = CH3COO (3), o-C6H4(COO)(COOH) (4)]. Reactions with m-phenylenediacetic acid [m-C6H4(CH2COOH)2] also gave the discrete tetracopper(II) cationic complex [Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)(CH2COOH))2(bpy)4](NO3)2 (5a) as well as the cluster polymer formulated as {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)2)(bpy)4](NO3)2}n (5b). The tetracopper structure of 1a is converted into a symmetrical rectangular core in complexes 3, 4, and 5b, where the hydroxo bridge is dissociated and, instead, two carboxylate anions bridge another pair of Cu(II) ions in a 1,1-O monodentate fashion. The similar reactions were applied to incorporate sugar acids onto the tetranuclear copper(II) centers. Reactions of 1a with delta-D-gluconolactone, D-glucuronic acid, or D-glucaric acid in dimethylformamide resulted in the formation of discrete tetracopper complexes with sugar acids, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-SA)2(bpy)4](NO3)2 [SA = D-gluconate (6), D-glucuronate (7), D-glucarateH (8a)]. The structures of 6 and 7 were determined by X-ray crystallography to be almost identical with that of 3 with additional chelating coordination of the C-2 hydroxyl group of D-gluconate moieties (6) or the C-5 cyclic O atom of D-glucuronate units (7). Those with D-glucaric acid and D-lactobionic acid afforded chiral one-dimensional polymers, {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-glucarate)(bpy)4](NO3)2}n (8b) and {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-lactobionate)(bpy)4(H2O)2](NO3)3}n (9), respectively, in which the D-Glc-1P-bridged tetracopper(II) units are connected by sugar acid moieties through the C-1 and C-6 carboxylate O atoms in 8b and the C-1 carboxylate and C-6 alkoxy O atoms of the gluconate chain in 9. When complex 7 containing d-glucuronate moieties was heated in water, the mononuclear copper(II) complex with 2-dihydroxy malonate, [Cu(mu-O2CC(OH)2CO2)(bpy)] (10), and the dicopper(II) complex with oxalate, [Cu2(mu-C2O4)(bpy)2(H2O)2](NO3)2 (11), were obtained as a result of oxidative degradation of the carbohydrates through C-C bond cleavage reactions.

Abstract  Applicability of a skin test induced by dinitrofluorobenzene [DNFB] to quantification of the actual level of cellular immunity [CI] in vivo and its level after an experimental immunomodulation intervention were evaluated in two breeds [40 animals in each] of fattening bulls [10-11 months old]. At the selected methodical procedure of intensity determination of the delayed type of hypersensitivity [DTH], its average value reached 4.5 + 1.5 mm in 80 animals, while in 77.5 % of bulls its level ranged from 3.6 to 9.6 mm. in 18.7 % from 2.0 to 3.5 mm and in 3.8 % remained less than 2.0 mm Evident expression of the reaction points to the possibility of application of the used methodical procedure of the skin test using DNFB to quantify the level of CI response in vivo in cattle. Percentual representation of animals according to the intensity of skin reaction [Tab. I] and concentration of total serum immunoglobulins [CS-Ig] and serum IgG [Tab. II] indicates the different cellular and humoral state of animals in investigated breeds. This is also confirmed by the recorded average values of mentioned parameters which were significantly lower [P < 0.01; or 0.05] In animals of the first breed [4.0 +/- 1.3 mm; 28.3 +/- 4.4 U ZST, 18.4 +/- 3.5 g . l-1] than in breed 2 [4.9 +/- 1.6 mm: 32.5 +/- 3.8 U ZST; 20.3 +/- 3.5 g . l-1]. The animals of each breed were divided into four experimental groups with the approximately equal actual levels of DTH [Tab. III]. Immunomodulation effects of a single administration of soluble fungal glucal [Pleurotus ostreatus] at the dose 5 mg [RFG 5 group] and 10 mg . kg-1 [RFG 10 group] and levamisol [Nilverm inj.] at the dose 5 mg . kg-1 [L 5 group] on CI response tested on day 30 after application were compared to the control. While animals of breed 1 demonstrated positive glucal effects. for both doses used on DTH reaction to DNFB, both in comparison to its level before application [P < 0.5] and to the level of control animals after its application [P < 0.05; or 0.01], [Tab. III]. similar effects of glucan were recorded in the bulls of breed 2 no. Potentiating effects of levamisol [5 mg . kg-1] on DTH to DNFB were observed in none of the breeds.

Abstract  beta-1,4-Galactosyltransferase has been investigated with regard to its acceptor specificity and used in the synthesis of galactosides with 5-thioglucose, glucal, deoxynojirimycin, modified N-acetylglucosamine, and glucose derivatives as acceptors. The galactoside products are potentially useful as endoglycosidase or glycosyltransferase inhibitors or as intermediates for the synthesis of complex oligosaccharides. The conformation of each enzyme product has been investigated with NMR; all are shown to possess similar glycosidic torsional angles based on a significant NOE between H-1 of Gal and H-4 of the acceptor. Comparison of the transferase reactions with the beta-1,4-galactosidase-catalyzed galactosyl transfer reactions indicates that the transferase reactions provide exclusively a beta-1,4-glycosidic linkage while the galactosidase reactions predominantly form a beta-1,6-glycosidic linkage.