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At least 883 records · Page 49Linked to original sources
PubMed1991

[Riboflavin Reference Standard (Control 891) of National Institute of Hygienic Sciences].

The raw material of riboflavin was examined for the preparation of the "Riboflavin Reference Standard (Control 891)". Analytical data obtained were as follows: melting point, 238.2 degrees C (decomposition); absorbance, E1%1cm = 859 (267 nm), 277 (372 nm), 327 (445 nm); infrared spectrum, same as Riboflavin Reference Standard (Control 872); thin-layer chromatography, 5 impurities were detected; high-performance liquid chromatography, 11 impurities were detected; loss on drying, 0.25%; optical rotation, [alpha]20D = -133.6 degrees; solubility, less than 16 min; assay, 100.1% against Riboflavin Reference Standard (Control 872). Based on the above results, this raw material was authorized to be the Reference Standard of the National Institute of Hygienic Sciences.

Chromatography, High Pressure Liquid↗
PubMed1991

[d-Camphor Reference Standard (Control 901) and dl-Camphor Reference Standard (Control 901) of National Institute of Hygienic Sciences].

The raw materials of d-camphor and dl-camphor were examined for the preparation of the "d-Camphor Reference Standard" and "dl-Camphor Reference Standard". Analytical data obtained were as follows: ultraviolet spectrum, lambda max = 257 nm; absorbance, E1%1cm(257 nm) = 723; infrared spectrum, 2956, 1742, 1045 cm-1; optical rotation, [alpha]20D = +42.9 degrees (d-camphor), [alpha]20D = -0.00 degrees (dl-camphor); melting point, 180 degrees C (d-camphor), 179 degrees C (dl-camphor); gas-chromatography, one impurity was detected in d-camphor and four impurities were detected in dl-camphor. Based on the above results, these raw materials were authorized to be the Reference Standards of the National Institute of Hygienic Sciences.

Camphor↗
PubMed1992

[Prednisolone reference standard (Control 911) of the National Institute of Hygienic Sciences].

Prednisolone was tested for preparation of the "Prednisolone Reference Standard (Control 911)". The quality of raw material was examined and compared with the previous Reference Standard (Control 872). Analytical data obtained were as follows: loss on drying, 0.10%; melting point, 233.2 degrees C (decomposition); optical rotation, [alpha]20D+98.77 degrees; UV spectrum, lambda max = 243nm; absorptivity, E1%1cm (243nm) = 413.5; IR spectrum, 1711, 1612, 1110, 888cm-1; one impurity was detected by thin-layer chromatography and high-performance liquid chromatography (HPLC), respectively; assay, 100.1% by HPLC. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Standard (Control 911).

Chromatography, Thin Layer↗
PubMed1992

[d-Camphor reference standard (Control 911) and dl-Camphor Reference Standard (Control 911) of the National Institute of Hygienic Sciences].

The raw materials of d-camphor and dl-camphor were examined for preparation of the "d-Camphor Reference Standard" and "dl-Camphor Reference Standard". Analytical data obtained were as follows: ultraviolet spectrum, lambda max = 290nm; infrared spectrum, 2958, 1742, 1045cm-1; optical rotation, [alpha]D20 = +42.7 degrees (d-camphor), [alpha]D20 = -0.3 degrees (dl-camphor); melting point, 180 degrees C (d-camphor), 179 degrees C (dl-camphor); gas-chromatography (GC), one impurity was detected in d-camphor and three impurities in dl-camphor; assay, 99.5% (d-camphor), 99.5% (dl-camphor) by GC. Based on the above results, these raw materials were authorized as the Japanese Pharmacopoeia Standard (Control 911).

Camphor↗
PubMed2003

[Cholecalciferol Reference Standard (Control 031) of National Institute of Health Sciences].

The raw material of cholecalciferol was examined for the preparation of the "Cholecalsiferol Reference Standard (Control 031)", The analytical data obtained were: melting point, 86.3 degrees C; UV spectrum, lambda max of 264.6 nm and specific absorbance in ethanol at 265 nm = 483.6; IR spectrum, same as that of the cholecalciferol Reference Standard (Control 003); optical rotation [alpha]20(D) = 105.1 degrees; thin-layer chromatography, one impurity was detected at 50 micrograms; high-performance liquid chromatography, total amount of impurities estimated to be less than 0.04%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Cholecalciferol Reference Standard (Control 031) of the National Institute of Health Sciences.

Chemical Phenomena↗
PubMed2003

[Ergocalciferol Reference Standard (Control 031) of National Institute of Health Sciences].

The raw material of ergocalciferol was examined for the preparation of the "Ergocalsiferol Reference Standard (Control 031)", The analytical data obtained were: melting point, 114.5 degrees C; UV spectrum, lambda max of 264.8 nm and specific absorbance in ethanol at 265 nm = 474.7; IR spectrum, same as that of the Ergocalciferol Reference Standard (Control 003); optical rotation, [alpha]20(D) = +104.6 degrees ; thin-layer chromatography, two impurities were detected at 50 micrograms; high-performance liquid chromatography, total amount of impurities estimated to be less than 0.04%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Ergocalciferol Reference Standard (Control 031) of the National Institute of Health Sciences.

Chemical Phenomena↗
PubMed1992

Properties of aspartate racemase, a pyridoxal 5'-phosphate-independent amino acid racemase.

Aspartate racemase from Streptococcus thermophilus contains no pyridoxal 5'-phosphate or other cofactors such as FAD, NAD+, and metal ions. It was affected by neither carbonyl reagents such as hydroxylamine nor sodium borohydride but was strongly inhibited by iodoacetamide and other thiol reagents. Aspartate, cysteate, and cysteine sulfinate were the only substrates. The Km values for L- and D-aspartate were 35 and 8.7 mM, respectively. The enzyme catalyzed the exchange of alpha-hydrogen of the substrate with the solvent hydrogen. Racemization of L-aspartate in 2H2O showed an overshooting in the optical rotation of aspartate before the substrate was fully racemized. This shows that the removal of alpha-hydrogen of the substrate is at least partially rate-determining. When L- or D-aspartate was incubated with aspartate racemase in tritiated water, tritium was incorporated preferentially into the product enantiomer. The results strongly suggest that aspartate racemase contains two hydrogen acceptors.

Amino Acid Isomerases↗
PubMed1992

Archaea contain a novel diether phosphoglycolipid with a polar head group identical to the conserved core of eucaryal glycosyl phosphatidylinositol.

The structure of a major ether polar lipid of the methanogenic archaeon Methanosarcina barkeri was identified as glucosaminyl archaetidylinositol. This lipid had archaeol (2,3-di-O-phytanyl-sn-glycerol) as a core lipid portion, and the polar head group consisted of 1 mol each of phosphate, myo-inositol and D-GlcN. The polar head group was identified by means of chemical degradations, phosphatidylinositol-specific phospholipase C treatment, permethylation analysis, and fast atom bombardment-mass spectrometry as glucosaminylinositol phosphate, which was linked to the glycerol backbone via a phosphodiester bond. The stereochemical configuration of the phospho-myo-inositol residue of glucosaminyl archaetidylinositol was determined to be 1-D-myo-inositol 1-phosphate by measuring optical rotation of phospho-myo-inositol prepared by nitrous acid deamination and alkaline hydrolysis from the lipid. 1H NMR of the intact lipid showed that GlcN was linked to C-6 position of myo-inositol as an alpha-anomer. It is, finally, concluded that the complete structure of this lipid is 2,3-di-O-phytanyl-sn-glycero-1-phospho- 1'[6'-O-(2"-amino-2"-deoxy-alpha-D-glucopyranosyl)]-1'-D-myo-inositol. This lipid has a hybrid nature of an archaeal feature in alkyl glycerol diether core portion and an eucaryal feature in the polar head group identical to the conserved core structure (GlcNp(alpha 1-6)-myo-inositol 1-phosphate) of glycosylated phosphatidylinositol which serves as a membrane protein anchor in eucaryal cells.

Carbohydrate Sequence↗
PubMed2004

Red blood cell deformability, aggregability and cytosolic calcium concentration in normal tension glaucoma.

AIM: The aim of the study was to determine the role of some erythrocyte patterns (Red Blood Cell deformability, aggregability, cytosolic calcium concentration) in normal tension glaucoma (NTG), compared with primary open angle glaucoma (POAG) and normal subjects. MATERIAL AND METHODS: Ninety patients entered the study, divided in three groups: age and sex-matched, otherwise normal subjects (30 patients), POAG (30 patients) and NTG patients (30 patients). Hemorheological parameters (elongation index [EI] and aggregability half time [At1/2] were detected using a laser diffractometer system (Laser-assisted Optical Rotational Cell Analyzer [LORCA]). Cytosolic calcium levels were measured using spectrofluorimetry. RESULTS: No significant difference in systemic variables and refractive error was found. Mean hematocrit level, cell volume, plasma protein level and coagulation factors did not show any statistical difference among groups and resulted to be in the range of normality. A significant decrease in EI measurements was demonstrated in the NTG group (p<0.001) only. Similarly, A-t1/2 measurements were significantly smaller in the NTG group than in the other groups (p<0.001). Cytosolic calcium levels were significantly higher in the NTG group than in the other groups (p<0.001) and they were correlated to the elongation index for each group and overall (r=-0.756, p<0.001). CONCLUSIONS: A significant decrease of erythrocyte deformability and increase in aggregability was found in NTG patients. These alterations seem to be inversely related to the intracytosolic calcium levels and they were not found in POAG patients and controls. Those results may contribute to understand the pathogenesis of normal tension glaucoma, suggesting a possible role played by red blood cells.

Blood Pressure↗
PubMed2000

Production of cis-1,2-dihydroxy-3-methylcyclohexa-3,5-diene (toluene cis glycol) by Rhodococcus sp. MA 7249.

An attractive method for producing cis-1,2-dihydroxy-3-methylcyclohexa-3,5-diene (toluene cis glycol) was developed employing a cis dihydrodiol dehydrogenase "deficient" strain of Rhodococcus (MA 7249). The toluene cis glycol produced was found to have optical rotations of [alpha]D25 = +25.8 (c 0.45, CH3OH) and +72.8 (c 0.42, CHCl3) which indicated an absolute configuration of (1S,2R) when compared with previously published values. When cultivated in laboratory fermentor in the presence of toluene vapors, MA 7249 reached a toluene cis glycol concentration up to 18 g/l in 110 h. Culture MA 7249 also accumulated cis (1S,2R) dihydrodiols from dihydronaphthalene, biphenyl, chlorobenzene, and styrene.

Journal Article↗
PubMed2000

Direct production of allitol from D-fructose by a coupling reaction using D-tagatose 3-epimerase, ribitol dehydrogenase and formate dehydrogenase.

Allitol was produced from D-fructose via a new NADH-regenerating enzymatic reaction system using D-tagatose 3-epimerase (D-TE), ribitol dehydrogenase (RDH), and formate dehydrogenase (FDH). D-fructose was epimerized to D-psicose by the D-TE of Pseudomonas cichorii ST-24 and the D-psicose was subsequently reduced to allitol by the RDH of an RDH-constitutive mutant, X-22, derived from Klebsiella pneumoniae IFO 3321. NADH regeneration for the reduction of D-psicose by the RDH was achieved by the irreversible formate dehydrogenase reaction, which allowed the D-psicose produced from d-fructose to be successively transformed to allitol with a production yield from D-fructose of almost 100%. The reactions progressed without any by-product formation. After separation of the product from the reaction mixture by a simple procedure, a crystal of allitol was obtained in a yield exceeding 90%. This crystal was characterized and determined to be allitol by HPLC analysis, its IR and NMR spectra, its melting point, and optical rotation measurement.

Journal Article↗
PubMed2003

Direct production of D-arabinose from D-xylose by a coupling reaction using D-xylose isomerase, D-tagatose 3-epimerase and D-arabinose isomerase.

Klebsiella pneumoniae 40bXX, a mutant strain that constitutively produces D-arabinose isomerase (D-AI), was isolated through a series of repeated subcultures from the parent strain on a mineral salt medium supplemented with L-Xylose as the sole carbon source. D-AI could be efficiently immobilized on chitopearl beads. The optimum temperature for the activity of the immobilized enzyme was 40 degrees C and the enzyme was stable up to 50 degrees C. The D-Al was active at pH 10.0 and was stable in the range of pH 6.0-11.0. The enzyme required manganese ions for maximum activity. Three immobilized enzymes, D-xylose isomerase (D-XI), D-tagatose 3-epimerase (D-TE and D-AI were used for the preparation of D-arabinose from D-xylose in a coupling reaction. After completion of the reaction, degradation of D-xylulose was carried out by Saccharomyces cerevisiae. The reaction mixture containing D-Xylose, D-ribulose and the product was then separated by ion exchange column chromatography. After crystallization, the product was checked by HPLC, IR spectroscopy, NMR spectroscopy and optical rotation measurements. Finally, 2.0 g of D-arabinose could be obtained from 5 g of the substrate.

Journal Article↗
PubMedDate not supplied

[The optical activity of the system cellulose acetate--mesophasogenic solvent in the formation of a lyotropic liquid-crystalline phase].

Vapors of a mesophasogenic solvent (which can form an liquid-crystalline phase with the polymer) have been found to actively affect the spatial structure and optical activity of natural polysaccharides (cellulose acetates). This process is accompanied by variations of the specific optical rotation value [alpha] within wide limits, including the inversion of the sign of [alpha]. The action of vapors obeys the dosage-effect rule, with lower doses producing a stronger effect. It was supposed that this approach can be applied to study the structural peculiarities of biopolymers such as DNA.

Cellulose↗
PubMed2006

Rheological properties of erythrocytes in patients suffering from morbid obesity. Examination with LORCA device.

UNLABELLED: Obesity is associated with many comorbid pathologies that lead to increased morbidity and increased mortality. Hemorheological changes in obesity are currently investigated as one of the risk factors for many comorbid pathologies. It has been found that erythrocyte hyperaggregation and a decrease in erythrocyte filterability have also been well documented in obesity patients. The aim of this study is to present preliminary results of the influence of weight reduction after vertical banded gastroplasty (VBG) on aggregation of red cells and red blood cells deformability. We studied seven patients who underwent VBG, median age 46 years (range 35-52), median BMI 52.1 kg/m(2) (range 36.6-66). Blood rheology changes and selected biochemical parameters were examinated before and 6 months after VBG. Erythrocyte elongation and red blood cells (RBC) aggregation were measured using the Laser-assisted Optical Rotational Cell Analyser (LORCA). The RBC aggregation index was significantly decreased, while the aggregation half-time (t(1/2)) significantly elongated after surgery. The syllectogram amplitude did not change. No differences in RBC deformability were observed in the postoperative period. CONCLUSION: We could conclude that among morbidly obese patients six months after VBG some beneficial changes of erythrocyte rheological parameters are observed. Further studies are necessary to confirm our preliminary results.

Adult↗
PubMed2006

[Study on the mustard of polysaccharides].

The objective of this study is to isolate and purify the polysaccharides fractions from mustard and to determine the constituent characters. Hot water extracting and ethanol precipitating method were employed to isolate polysaccharides. After the removal of protein by Sevag method, the purified mustard polysaccharides were dried by frozen drier. The amount of total carbohydrates of mustard polysaccharides was measured with phenol-sulfuric acid method. IR spectrometry, UV-spectrophotometer, and automatic spectropolarimeter were used to determine the characteristic absorption and optical rotation of the polysaccharides, respectively. Size exclusion chromatography with laser light scattering technology was employed to measure the molecular masses. The monosaccharides contained in the mustard polysaccharides were analysed by HPLC. The amount of total carbohydrates in mustard polysaccharides is 98.96%. The molecular weight distribution was 1.42 x 10(4)-2.55 x 10(6), and eighty percent was distributed in 2.1 x 10(5). The monosaccharide constituent of mustard polysaccharides were glucose, fructose, arabinose, galactose and xylose, and their molar proportions are 21.4 : 12.89 : 5.6 : 4.1 : 2.5, respectively.

Molecular Weight↗
PubMed1990

[Antigenic polysaccharides of bacteria. 37. Structure of the polysaccharide chain of Pseudomonas syringae pv.tabaci (serogroup VII) lipopolysaccharide].

The structure of the O-specific polysaccharide chain of Pseudomonas syringae pv. tabaci strain 223 (serogroup VII) lipopolysaccharide was established on the basis of one- and two-dimensional 1H NMR analysis, 13C NMR analysis and calculation of optical rotation. The structure determined by the non-destructive way was confirmed by acid hydrolysis and methylation. (Sequence: see text). O-Antigen of the strain studied is similar in structure and serological properties to O-antigens of Pseudomonas syringae strains belonging to serogroup I.

Antigens, Bacterial↗
PubMed1991

6-Deoxy-D-talan and 6-deoxy-L-talan. Novel serotype-specific polysaccharide antigens from Actinobacillus actinomycetemcomitans.

Serotype-specific polysaccharide antigens from Actinobacillus actinomycetemcomitans ATCC 29523 (serotype a) and NCTC 9710 (serotype c) were extracted from whole cells by autoclaving and purified by ion-exchange chromatography and gel filtration. Analysis of component sugars by gas-liquid chromatography-mass spectrometry, high performance liquid chromatography, and NMR together with optical rotation data showed that the serotype a antigen was composed solely of 6-deoxy-D-talose, whereas the serotype c antigen consisted of 6-deoxy-L-talose. Structural analysis indicated that both of these antigens were composed of closely related repeating units, -3)-6-deoxy-alpha-D-Talp-(1-2)-6-deoxy-alpha-D-Talp-(1-(sero type a) and -3)-6-deoxy-alpha-L-Talp-(1-2)-6-deoxy-alpha-L-Talp-(1-(sero type c). 1H and 13C NMR analysis showed that both of these serotype antigens contained one acetyl group/2 sugar residues. These acetyl groups localized at the O-2 position of 3-linked 6-deoxy-D-talose (serotype a) or O-4 position of 3-linked 6-deoxy-L-talose residues (serotype c), respectively. These results coupled with our previous findings on the serotype b antigen (Amano, K., Nishihara, T., Shibuya, N., Noguchi, T., and Koga, T. (1989) Infect. Immun. 57, 2942-2946) showed that the serotype antigens from A. actinomycetemcomitans are a group of novel polysaccharides with structural features closely related biosynthetically.

Actinobacillus↗
PubMed1977

Thermal denaturation of cytochromes c of horse cow, and Candida krusei in aqueous guanidine hydrochloride.

Thermal denaturation of cytochromes c of horse, cow, and Candida krusei in aqueous guanidine hydrochloride in the neutral pH region was studied by means of absorption and optical rotation measurements. The values of standard free energy change upon denaturation were estimated over the temperature range from 3 to 51 degrees C. Large differences in the heat capacity of the native and denatured states amounting to several kcal/mol-deg were obtained for all three kinds of cytochromes c. These lead to a change in the sign of both the enthalpy and entropy change of denaturation, with maximum stability of the native state at 12 degrees C for horse and bovine cytochromes c and at 9 degrees C for Candida krusei.

Amino Acids↗