Abstract  The equilibrium reactions between deprotonated D-lactobionic acid (4-O-beta-D-galactopyranosyl-D-gluconic acid) and cobalt(II), nickel(II), copper(II), zinc(II), cadmium(II), and mercury(II) have been studied by potentiometric and spectrophotometric methods in aqueous solution. All measurements have been carried out at a temperature of 20.0 +/- 0.1 degrees C and at an ionic strength of 0.100 M (NaNO3) with the corresponding stability constants calculated by applying computational methods. The interactions between the proposed cations with deprotonated D-lactobionic acid were compared with those corresponding to D-gluconic acid. Compounds of type: Co(C12H21O12)(2) . 2H(2)O . C2H5OH, Ni(C12H21O12)(2) . 2H(2)O . C2H5OH, Cu(C12H21O12)(2) . 2H(2)O . C2H5OH, Zn(C12H21O12)(2) . 2H(2)O . C2H5OH, and Cd(C12H21O12)(2) . 2H(2)O . 0.5C(2)H(5)OH have been isolated. These metal-sugar salts were characterized by elemental, thermogravimetric, and susceptibility analyses and FT-IR, UV-visible absorption, diffuse reflectance, and C-13 NMR spectroscopies.

Abstract  The kinetics and mechanism of the oxidation of 2-deoxy-D-glucose (dGlc) by Cr-VI which yields 2-deoxy-D-gluconic acid and Cr-III as final products when a ten-fold or higher excess of sugar over Cr-VI is used, have been studied. The redox reactions occur through Cr-VI --> Cr-IV --> Cr-III and Cr-VI --> Cr-V --> Cr-III paths. The experimental data were fitted with a multilinear regression program. The complete rate law for the chromium(VI) oxidation reaction is expressed by -d[Cr-VI]/dt = {c[H+] + (d + e[H+] + f[H+](2)) [dGlc]}[Cr-VI], where c = (5 +/- 1) x 10(-4) dm(3) mol(-1) s(-1), d = (3 +/- 2) x 10(-4) dm(3) mol(-1) s(-1), e = (115 +/- 13) x 10(-4) dm(6) mol(-2) s(-1) and f = (402 +/- 17) x 10(-4) dm(9) mol(-3) s(-1), at 50 degrees C. Chromium(V) is formed in a rapid step by reaction of the radical dGlc and Cr-VI and Cr-V reacts with dGlc faster than does Cr-VI. The chromium(V) oxidation of dGlc follows the rate law -dCr(V)/dt = (k(1) + k(2)[H+])[dGlc][Cr-V], where k(1) = 2.52 x 10(-4) dm(3) mol(-1) s(-1) and k(2) = 54.0 dm(6) mol(-2) s(-1), at 25 degrees C. The EPR spectra show that three 1:1 Cr-V:dGlc intermediate complexes (g(1) = 1.9781, g(2) = 1.9752, g(3) = 1.9758) are formed in rapid pre-equilibria before the redox steps.

Abstract  The interaction of D-gluconic acid with Mn-II, Co-II, Ni-II, Cu-II, Cd-II, Hg-II and Pb-II has been investigated. Compounds of the type Mn(D-gluconate)(2) . 3H(2)O, Co(D-gluconate)(2) . 3H(2)O, Ni(D-gluconate)(2) . 3H(2)O, Cu(D-gluconate)(2) . 3H(2)O, Cd(D-gluconate)(2), Hg(D-gluconate)OH and Pb(D-gluconate), have been isolated. These metal-sugar salts were characterized by elemental, thermogravimetric analyses and FT-IR, UV-vis absorption, EPR and C-13 NMR spectroscopies. In addition, a quantitative study of the equilibria involved in the interaction of this sugar and the above mentioned metal ions in an aqueous medium was carried out by means of potentiometric measurements of the hydrogen ion concentrations at 20 degrees C and mu = 0.100 M (NaNO3). On the basis of spectroscopic studies, possible structures of these complex species were discussed.

Abstract  Novel macrolactam and macroketone analogues of the migrastatin macrolide core have been synthesised from tri-O-acetyl-D-glucal in order to facilitate structure-activity studies. The Horner olefination, followed by ring-closing metathesis were key steps in the synthesis of the macroketone. The ability of the macroketone and macrolactam derivatives to inhibit the migration of gastric tumour cells as determined using a transwell migration assay were compared with macrolactone analogues and dorrigocin A analogues. One dorrigocin A congener was the most potent inhibitor of gastric cancer cell migration. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).

Abstract  Experiments were conducted to determine the antimicrobial efficacies of peroxyacetic acid and other organic acids (fumaric acid; malic acid; citric acid; gluconic acid; levulinic acid; pyruvic acid; caprioc acid, caprylic acid, and capric acid) with and without a non-ionic surfactant (EG) on reduction of coliform, Escherichia coil O157:H7, and aerobic plate count (APC) bacteria on beef trimmings. Inoculated beef trimmings with E. coli O157:H7 were processed with antimicrobial treatments for 15 s with 0.2 g/L peroxyacetic acid and other organic acids (30 g/L) in combination with or without a non-ionic surfactant. Results suggest that most organic acids were effective in reducing the bacterial populations on inoculated beef trimming. Among organic acids, 30 g/L caprylic acid was highly effective in reducing more than 4.78, 4.73, and 2.48-logs of conform, E. coil O157:H7, and APC populations respectively. The 30 g/L of the pyruvic acid was also found to be effective and reduced 1.84, 1.68, and 1.08 log(10) CFU/g of conform, E. coil O157:H7, and APC counts compared to the control. The highest concentration (at 30 g/L level) of the gluconinc acid tested in this study resulted in no reduction in conform, E. coil O157:H7, and APC counts. (C) 2015 Elsevier Ltd. All rights reserved.

Abstract  Paenibacillus polymyxa has widely been studied as a model of plant-growth promoting rhizobacteria (PGPR). Here, the genome sequences of 9 P. polymyxa strains, together with 26 other sequenced Paenibacillus spp., were comparatively studied. Phylogenetic analysis of the concatenated 244 single-copy core genes suggests that the 9 P. polymyxa strains and 5 other Paenibacillus spp., isolated from diverse geographic regions and ecological niches, formed a closely related clade (here it is called Poly-clade). Analysis of single nucleotide polymorphisms (SNPs) reveals local diversification of the 14 Poly-clade genomes. SNPs were not evenly distributed throughout the 14 genomes and the regions with high SNP density contain the genes related to secondary metabolism, including genes coding for polyketide. Recombination played an important role in the genetic diversity of this clade, although the rate of recombination was clearly lower than mutation. Some genes relevant to plant-growth promoting traits, i.e. phosphate solubilization and IAA production, are well conserved, while some genes relevant to nitrogen fixation and antibiotics synthesis are evolved with diversity in this Poly-clade. This study reveals that both P. polymyxa and its closely related species have plant growth promoting traits and they have great potential uses in agriculture and horticulture as PGPR.

Abstract  The oxidative dehydrogenation of L-sorbose to 2-keto-L-gulonic acid in aqueous medium is reviewed with special emphasis on the use of promoted platinum catalysts. The activity of alumina- or carbon-supported platinum can be increased by selective deposition of bismuth or lead onto the supported platinum particles, and by preadsorbed strongly basic tertiary and quaternary amines. Both methods have a negative influence on the selectivity, but the effect of supported N-bases is less detrimental. Aromatic and cycloaliphatic amines, some phosphines and aminophosphines improve the selectivity to 2-keto-L-gulonic acid. The amine and phosphine modifiers are used in very small amounts, less than 600 ppm related to sorbose. The best modifier is hexamethylenetetramine, which provides 99-95% selectivity up to 30% conversion. The efficiency of metal, amine and phosphine type promoters is compared.

Abstract  Hydrolysis of methyl 6-chloro-6-deoxy-2,3,4-tri-O-methyl-alpha-D-glucopyranoside (19b) and Swern oxidation of the resulting anomeric hemiacetals (20) gave 6-chloro-6-deoxy-2,3,4-tri-O-methyl-D-glucono-1,5-lactone (21), treatment of which with 1,2-bis(trimethylsilyloxy)ethane in the presence of trimethylsilyl trifluoromethanesulfonate gave 6-chloro-1,6-dideoxy-1,1-ethylenedioxy-2,3,4-tri-O-methyl-D-glucopyranose (23a). Conversion of (23a) into the corresponding 6-iodo compound (23b) and treatment of this with 1,8-diazabicyclo[5.4.0]undec-7-ene afforded the enolic ortho ester 1,6-dideoxy-1,1-ethylenedioxy-2,3,4-tri-O-methyl-D-xylo-hex-5-enopyranose (26). Reaction of(26) with methylmagnesium iodide, or with titanium tetrachloride, gave (1R,6S,7R,8R,9S)-7,8,9-trimethoxy-6-methyl-2,5-dioxabicyclo[4.3.1]decan-1-ol (34), or (2S,3R,4R)-5,5-ethylenedioxy-2,3,4-trimethoxycyclohexanone (28), respectively.

Abstract  In acidified dairy products, the size of the whey protein particles could play a key role in the final structure of the gel. In the present study, small (SM; 2.5 +/- 1.2 mu m), medium (MM; 4.2 +/- 2.2 mu m), and large (LM; 18.4 +/- 7.2 mu m) whey protein microbeads were produced by mixing a 150 g.kg(-1) whey protein isolate (WPI) solution and n-dodecane in the presence of polyglycerolpolyricinoleate (PGPR) surfactant at different shear rates and were then stabilized through heat gelation. The microbeads were then washed by centrifugation, dispersed at 70 or 90 g.kg(-1) in milk ultrafiltrate, and acidification was performed at 35 A degrees C by adding glucono-delta-lactone to achieve the final pH of similar to 4.5 in 6 h. Acid gelation was monitored using small deformation rheology, while the gel microstructure was investigated microscopically. The results showed that smaller size of microbeads promoted gels with a higher stiffness and a smaller pore size distribution. The effects were particularly significant at SM microbeads as the number of particles in this system was higher than in LM or MM, hence more connectivity between particles.

Abstract  The destabilization of water-in-oil (W/O) emulsions greatly restricts their application. Converting the inner water droplets into soft solid-like gelled particles is an appealing strategy to improve the stability of W/O emulsions. In the present communication, we propose a novel method for preparing stable W/O emulsions containing gelled water droplets. In this method, the 3% (w/v) casein dispersions containing 0.9% (w/v) glucono-delta-lactone (GDL) and soybean oil with 2% or 6% lipophilic emulsifier polyglycerol polyricinoleate (PGPR) were homogenized to form W/O emulsions. Three hours later, the GDL-induced gelation of caseins in the inner aqueous phase occurred; thus, the W/O emulsions containing gelled water droplets were formed. The stability of the emulsions was characterized by Turbiscan analysis, particle size changes and visual inspection of phase separation. It was found that the W/O emulsions containing GDL-induced casein gels in the inner aqueous phase showed higher resistance to destabilization than the non-gelled W/O emulsions. In addition, the stability of the emulsions formulated by the gelled aqueous phase and 2% PGPR was even higher than emulsions with 6% PGPR in the absence of the gelled aqueous phase. These findings suggested that this method is an effective strategy for improving the long-term stability of W/O emulsions. (C) 2016 Elsevier Ltd. All rights reserved.

Abstract  Objective. Hyperparathyroidism is a generalized alteration of calcium, phosphorus and bone metabolism due to an increased secretion of parathyroid hormone (PTH). In addition to the paraneoplastic ectopic type, we can distinguish three eutopic types of hyperparathyroidism, i.e., the primary form, mostly due to a benign or malignant tumor of parathyroid gland, the secondary form, typical of kidney disease and tertiary form, due to the progression of secondary forms. There is not agreement, in medical literature, on the treatment of these patients. To establish the correct therapeutic approach in patients with hyperparathyroidism, we have followed a group of symptomatic subjects suffering from primary, secondary and tertiary hyperparathyroidism, taking into account the therapeutic needs.

Materials and Methods. We followed for 12 months 155 patients suffering from primary, secondary and tertiary hyperparathyroidism; 82 were in end stage kidney disease, 93 were hypertensive. Subjects with primary forms has been treated, before parathyroidectomy, with idration (physiological solution of NaCl), bisphosphonates i.v. (pamidronate 60-90 mg in 4-6h) and, if serum calcium was higher than 12mg/dl, loop diuretics (furosemide 40 mg/day). Subjects with secondary forms has been treated with hypophosphoric diet, phosphate bindings (calcium carbonate 1 g/day) and oral calcitriol (1 mu g/d) before subtotal parathyroidectomy. After surgery it was administered support therapy with calcium gluconate (40 ml/day) and vitamin D (2.5mg/d) until serum calcium normalization.

Results. There were 55 cases of post surgery hypertensive attack treated with clonidine (300 mu g/d); 8 months later there was not relapses but in all patients there was reduction of serum calcium concentration that required a substitutive treatment (calcium I g/day and calcitriol 1 mu g/day). There was 1 case of heavy hypocalcemic state treated with calcium gluconate i.v. (40 ml/day).

Conclusions. A correct approach to a non-paraneoplastic hyperparathyroid patient need of an integration of both current medical and surgical options. In primary forms the first option is the surgical approach supported by medical treatment. In secondary forms medical approach is preferable to control renal and vascular complications, while surgical therapy is to prefer in non-responders to medical therapy forms. Clin Ter 2009; 160(1):21-24

Abstract  The preparation of a novel carbohydrate lactone is reported, in excellent yield, from d-gluconolactone; ring-opening polymerization of the lactone yields a functionalized cyclic aliphatic polyester.

Abstract  In the Rh(2)(OAc)(4)-catalyzed amidoglycosylation of glucal 3-carbamates, anomeric stereoselectivity and the extent of competing C3-H oxidation depend on the 4O and 6O protecting groups. Acyclic protection permits high alpha-anomer selectivity with further improvement in less polar solvents, while electron-withdrawing protecting groups limit C3-oxidized byproducts. Stereocontrol and bifurcation between alkene insertion and C3-H oxidation reflect an interplay of conformational, stereoelectronic, and inductive factors.

Abstract  We demonstrate a generic new approach to produce homogeneous and reproducible hydrogels from low molecular weight hydrogelators using the controlled hydrolysis of glucono-delta-lactone (GdL). GdL slowly hydrolyses in water to give gluconic acid, which controllably lowers the pH. This hydrolysis is slower than the rate of dissolution; hence uniform pH change throughout the sample is possible. This results in homogeneous hydrogels that are unaffected by their shear or mixing history. A further advantage of this method is that it allows the gelation process to be monitored, giving further insight into the mechanism by which gelation occurs.

Abstract  Raman scattering and its polarized extension, Raman optical activity (ROA), are commonly used for monitoring of molecular conformational equilibria in solutions. This is complicated for saccharides due to extensive motions of the hydroxyl groups and other molecular parts. Standard interpretation procedures involving ab initio spectral simulations for a limited set of conformers are not adequate. In this study, a more general approach is proposed for the gluconic acid anion taken as a model compound, where quantum simulations of the spectra are directly coupled with molecular dynamics (MD) techniques. Such a multiscale approach reveals how the structural information is encoded in the broadened spectral lines. The spectra were simulated for solvent-solute clusters generated by MD. Conformational averaging was enabled by a limited library of conformers for which the spectral parameters could be calculated ab initio and moved on the MD geometries by Cartesian coordinate tensor transfer techniques. The B3LYP/CPCM/6-31+G** approximation was used as a default for computation of the source force fields and polarizability derivatives. The spectra thus obtained relatively faithfully reproduced most of the experimental features. The Amber and polarizable Amoeba MD force fields produced similar results; application of the latter, however, was limited by the long time necessary to achieve a converged conformational equilibrium. Both MD simulation and spectral averaging suggest that the hydroxyl groups as well as the backbone C-C bonds rotate relatively freely, with some restrictions in the vicinity of the carboxyl group. In spite of the averaging, spectral response of characteristic vibrational normal mode families, such as CH and OH bending, can clearly be identified in the spectra. The simulations thus confirm the experimental fact that flexible saccharides exhibit significant vibrational activity that reveals precious information about molecular structure and dynamics encoded in the Raman and ROA spectral shapes.

Abstract  We report a girl with partial DiGeorge anomaly associated with a distal chromosome 10p deletion. The initial manifestation tvas hypocalcemic convulsion at the age of 14 days. The patient was small for her gestational age and showed symptoms of poor feeding and inspiratory strider. Facial dysmorphisms included a cupped ear, hypertelorism, do downslanted and short palpebral fissures. frontal bossing, anterverted nostrils, a flat nasal bridge, and micrognathia. Developmental delay was also noted. Hypoplasia of the thymus was detected by ultrasound examination, but results of immunologic studies were all normal at 6 weeks of age. The echocardiogram, brain ultrasound, electroencephalogram, and magnetic resonance images of the brain were normal, but brainstem auditory evoked potentials shelved bilateral sensorineural hearing loss. Chromosomal analysis showed 46, XX, del(10)(p12.3); the parents had normal karyotypes. After treatment with vitamin D, calcium gluconate, and magnesium sulfate, the patient's serum calcium and magnesium levels were within normal limits. She was discharged and received regular follow-up at our clinic for physical therapy and to ensure adequate supply of divalent cations. Complex partial seizure was noted at the age of 1 year and was controlled with carbamazepine. To our knowledge, this is the first Taiwanese reported to have partial DiCeorge anomaly associated with 10p deletion. We recommend that standard karotyping should be performed in children suspected to have this anomaly.

Abstract  The C1-C14 portion of altohyrtins (spongistatins) was prepared in a convergent manner from 3,4,6-tri-O-acetyl-D-glucal via a chelation-controlled methylation of ketone, dithiane couplings with epoxides, and a thermodynamically-controlled spiroacetalization. (C) 1998 Elsevier Science Ltd. All rights reserved.

Abstract  The development of high-active, selective and low-cost electrocatalysts for oxygen reduction reaction (ORR) is of major interest for catalysis in fuel cells. In this article, we present various nitrogen-doped graphenes as high performance non-metal electrocatalysts for ORR based on graphene thermally treated with cyanamide. The impact of treatment temperature on the structure and ORR performance of prepared samples is systematically investigated. Obtained results indicate that electrochemically active surface area (ECSA) and electrocatalytic ORR activity at both neutral and alkaline conditions are enhanced for samples treated at higher temperatures showing a clear correlation between ECSA and ORR activity. A comparison of determined ORR performances with XPS results demonstrates that not the total quantity of nitrogen improves ORR activity, but we think that optimum content of graphitic nitrogen functionality is mainly responsible for the improved electrocatalytic performance. The main novelties of our work are specifically the voltammetric studies of the ORR mechanism on prepared nitrogen-doped graphene and the investigation of the electrocatalytic activity in presence of glucose and D-gluconic acid in pH-neutral medium. We ascertained superior tolerance of nitrogen-doped graphene towards D-gluconic acid poisoning as well as glucose oxidation. Especially, the sample prepared at 1000 degrees C exhibits improved electrocatalytic ORR performance compared to graphene-based materials, and significantly enhanced long-term operation stability, D-gluconic acid and glucose tolerance than commercial Pt/C, thus, perfectly suited for use in single-compartment glucose-based fuel cells operating at pH-neutral conditions. (C) 2015 Elsevier Ltd. All rights reserved.

Abstract  Some fungal metabolites, either primary or secondary, as well as enzymes and other biotransformation products of fungal origin play a strategic role in many technologies and in particular in food processing. Among these, organic acids appear to be of major interest. Citric acid is already produced at more than 600x10(3) Tons/year and the market demand for other acids such as gluconic, lactic and malic is continuously increasing. This review is mainly devoted to the most recent advances in the production of organic acids from immobilized fungal cell systems.

Fumaric acid production by immobilized Rhizopus arrhizus is reported as a case study. In fact, the fermentative production of this acid, which has long been abandoned for economic reasons and substituted by direct chemical synthesis, might greatly benefit from the use of an immobilized-cell based technology.

Abstract  The application properties of sugar acids and a hydrolysate containing sugar acids were investigated in order to evaluate their potential for removing heavy metals from waste incineration residues. Exemplarily the biomass residue molasses, which is rich in carbohydrates, was oxidized under acidic conditions to yield a hydrolysate containing natural chelating agents. The leaching capacities of the complexing agents containing solutions were examined in a series of batch tests with a fly ash from municipal waste incineration. Gluconic acid with a concentration of 0.5%, 2% and 5% and a molasses hydrolysate with a sugar acid content of approx. 1.8% were applied.

It is demonstrated that sugar acids, as well as a biomass hydrolysate, which contains sugar acids, can be used as effective agents for the remediation of heavy metals which are bound to or included in the matrix of waste incineration residues. Advantageous for the leaching process is that sugar acids are particularly effective in the pH range which is normally measured for waste incineration residues. (C) 1998 Elsevier Science Ltd. All rights reserved.

Abstract  The adsorption ability of Cu(II) using chitosan from simulated rinse solutions containing chelating agents was studied. Four chelating agents including ethylenediaminetetraacetic acid (EDTA), citric acid, tartaric acid and sodium gluconate were selected. It was shown that the concentration ratio of chelating agent to Cu(II) as well as the NaOH concentration significantly affected the adsorption capacity. Competition between coordination of Cu(II) with unprotonated chitosan and electrostatic interaction of Cu(II) chelates with protonated chitosan played an important role in this adsorption system. The maximum adsorption capacity was found within each optimal pH range. This work provided a simple criteria for adsorption removal of Cu(II) from such industrial rinse solutions (0.3-5.0 mol/m(3)) using chitosan. (C) 1999 Elsevier Science Ltd. Aii rights reserved.

Abstract  Gel-permeation chromatography on the COO- and COOH forms of Ultrahydrogel 120 of aqueous solutions of D-glucose irradiated with ultrasound and gamma-rays, followed by g.l.c.-m.s. of the trimethylsilylated methoximated derivatives of the products, revealed derivatives of gluconic acid and hexulosonic acids after irradiation in the presence of air and 2-deoxy-arabino-hexonic and gluconic acid after irradiation under argon. A small proportion of products was formed with molecular weights larger than that of glucose and which contained an enolic structure.

Abstract  The effect of the pH and the type of acidulant (citric acid or glucono-delta-lactone) of the recovery medium on the thermal resistance of Bacillus stearothermophilus ATCC 12980 was studied. The spores were heated in bidistilled water as a reference substrate and in acidified mushroom extract using citric acid or glucono-delta-lactone as acidulants (pH 6.2) and subcultured in reference (pH 7) and acidified (pH 6.2) media. A period of treatment-dependent pH sensitization was observed in heat-treated spores. In all cases, D values were lower in the acidified recovery medium than those obtained in the reference medium, but the type of acidulant used in the recovery medium had no influence on the D values. No influence on z values was observed as a consequence of the different recovery media, but they changed within a range of 7 to 10 degrees C as a function of the different heating substrates. Glucono-delta-lactone proved to be as effective as citric acid in controlling the microbiological spoilage of foods. The pH has a great influence on decreasing the D values, mainly when acidification of the substrate and acidification of the recovery medium are combined. Consequently, it would be appropriate to take this effect into account in process calculations or validation.

Abstract  Artiodactyls possess abundant neutral glycosidase activity in liver, kidney and intestine, This enzyme is cytosolic and displays a more neutral pH optimum, more acidic isoelectric point and broader substrate range than the corresponding acidic beta-galactosidases. The neutral glycosidases were more thermolabile than the respective acidic beta-galactosidases and displayed a relative molecular mass approximating 60 kDa. This isozyme appeared to bca minor species in both rat and dog liver. The porcine enzyme was studied in more detail. Porcine neutral glycosidase activity was detected in 45-day gestational fetuses in both liver and kidney but not brain. Fetal kidney activities were about half those observed in adult kidney extracts. Porcine neutral glycosidase was immunologically distinct from acidic beta-galactosidase and was immunologically similar to the corresponding isozymes from deer, ovine and bovine liver. Porcine neutral glycosidase was moderately inhibited by D-galactonic acid gamma-lactone and strongly inhibited by D-gluconic acid delta-lactone; however, acidic beta-galactosidase was not inhibited by the delta-lactone. Inhibition by the gamma-lactone was competitive for both enzymes. 4-Methylumbelliferyl-beta-D-galactoside, glucoside and -xyloside competed for the same active site. A polymorphism for fast- and slow-migrating isozymes of porcine neutral glycosidase was observed, which appeared to be under genetic control. (C) 1997 Elsevier Science Inc.