scholarly journals Specific optical rotation is a versatile tool for the identification of critical micelle concentration and micellar growth of tartaric acid-based diastereomeric amphiphiles

Chirality ◽  
2017 ◽  
Vol 29 (12) ◽  
pp. 836-846 ◽  
Author(s):  
Vijay Raghavan ◽  
Prasad L. Polavarapu
Keyword(s):  
Critical Micelle Concentration ◽  
Tartaric Acid ◽  
Optical Rotation ◽  
Specific Optical Rotation ◽  
Micellar Growth ◽  
Versatile Tool

scholarly journals Immunochemical studies on blood groups LXII. Fractionation of hog and human A, H, and AH blood group active substance on insoluble immunoadsorbents of Dolichos and Lotus lectins.

1976 ◽  
Vol 143 (2) ◽  
pp. 422-436 ◽  
Author(s):  
M E Pereira ◽  
E A Kabat
Keyword(s):  
Blood Group ◽  
Optical Rotation ◽  
Gastric Mucin ◽  
Specific Optical Rotation ◽  
Dolichos Biflorus ◽  
Blood Group A ◽  
Analytical Properties ◽  
Group Substance ◽  
Group A

The purified lectins from Lotus tetragonolobus and Dolichos biflorus were coupled to Sepharose 2B to make insoluble adsorbents for purification and fractionation of blood group A and H active glycoproteins. With both adsorbents, hog gastric mucin A + H blood substance (HGM), purified by phenol-ethanol precipitation, yielded fractions showing only A, only H, or AH activities. The AH fraction was obtained when the adsorbent column was overloaded with HGM and its A and H specificities seem to be carried on the same molecules since they were not separable by chromatography on either column. However A and H specificities of blood group substance from the stomach of a presumably heterozygous individual hog were both on the same molecules as they too could not be fractionated on either column. Analytical properties of the isolated fractions were generally similar to those of the unfractionated material, the purfied A substances had a higher galactosamine/fucose ratio than did the H substances. Although the original A + H showed very little specific optical rotation, the separated A and H substances rotated positively and negatively, respectively. The lectin-Sepharose adsorbents have also proven useful in isolating A or H substances directly from the crude commercial hog gastric mucin. Blood group A2 substance from a human ovarian cyst yielded two fractions on the Lotus-Sepharose column; the effluent did not interact with the Lotus lectin but precipitated the Ulex and Dolichos lectins and anti-A, and appears to contain type 1 H determinants. The other fraction reacted with Lotus and Ulex lectin as well as with Dolichos and anti-A.

Identification of d- or di-∝-Tocopherol in Pharmaceuticals, Food Supplements, or Feed Supplements: A Collaborative Study

1975 ◽  
Vol 58 (3) ◽  
pp. 585-594
Author(s):  
Stanley R Ames ◽  
Emma-Jane E Drury
Keyword(s):  
Vitamin E ◽  
Oxidation Product ◽  
Optical Rotation ◽  
Collaborative Study ◽  
Food Supplements ◽  
Tocopheryl Acetate ◽  
Specific Optical Rotation ◽  
Feed Supplements ◽  
Before And After ◽  
Optical Rotations

Abstract A collaborative study was conducted to evaluate a method for identifying d- or dl-∝-tocopherol in pharmaceuticals, food supplements, or feed supplements. The sample is extracted and saponified, the extraneous color is removed by chromatography, and the sample is assayed for vitamin E. Optical rotations are determined before and after formation of the ferricyanide oxidation product. The specific optical rotation of the oxidation product is negligible for the dJ-form and +25.5° for the d-form. Statistical analysis of the data reported by 8 collaborators for the standard d-∝-tocopheryl acetate and for 6 unknown samples indicates a significant interaction between laboratories and samples. The mean coefficients of variation among laboratories for the determinations of the corrected specific optical rotation of the standard and the rotation ratio for the unknown samples containing d-∝-tocopherol were 11.7 and 21.6%, respectively, for all laboratories and 5.8 and 11.8%, respectively, for experienced laboratories. This identification test for vitamin E is acceptable for determining the form of vitamin E as either d or dl, but is not acceptable for accurately determining mixtures of the 2 forms. The method has been adopted as official first action for the identification of d- or dl-∝-tocopherol.

Temperature dependence of specific optical rotation of an aqueous levoglucosan solution

2018 ◽  
Vol 67 (11) ◽  
pp. 2155-2156
Author(s):  
A. V. Orlova ◽  
N. N. Kondakov ◽  
Yu. F. Zuev ◽  
L. O. Kononov
Keyword(s):  
Temperature Dependence ◽  
Optical Rotation ◽  
Specific Optical Rotation

Structure of the lipopolysaccharide O-chain of Yersinia enterocolitica serotype O:5,27

1987 ◽  
Vol 65 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Malcolm B. Perry ◽  
Leann L. MacLean
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Yersinia Enterocolitica ◽  
Lipid A ◽  
Optical Rotation ◽  
Periodate Oxidation ◽  
Partial Hydrolysis ◽  
Specific Optical Rotation ◽  
Core Oligosaccharide ◽  
Magnetic Resonance Studies ◽  
Serotype O

The cellular lipopolysaccharide produced by Yersinia enterocolitica serotype O:5,27 was of the S-type and composed of an antigenic O-chain polysaccharide linked through a core oligosaccharide region, which in turn was linked through 3-deoxy-D-manno-octulonosyl units to a lipid A moiety. The O-chain polysaccharide was composed of equal molar amounts of L-rhamnose and D-xylulose. By partial hydrolysis, periodate oxidation, methylation, specific optical rotation, and 13C and 1H nuclear magnetic resonance studies, the structure of the O-chain was established as being a linear backbone of alternating 1,3-linked α-L-rhamnopyranosyl and β-L-rhamnopyranosyl units, to which 2,2-linked β-D-threo-pent-2-ulofuranoside (D-xylulofuranoside) units were present on every L-rhamnopyranosyl residue, as shown below.[Formula: see text]

ChemInform Abstract: Synthesis and Structure-Optical Rotation Relationships of Homochiral, Monodisperse, Tartaric Acid-Based Dendrimers.

ChemInform ◽  
2010 ◽  
Vol 26 (4) ◽  
pp. no-no
Author(s):  
H.-F. CHOW ◽  
C. C. MAK
Keyword(s):  
Tartaric Acid ◽  
Optical Rotation

Synthesis of anisomycin. Part I. The stereospecific synthesis of N-benzoyl-2-(p-methoxybenzyl)-3-hydroxy-4-carboxamido pyrrolidine and the absolute configuration of anisomycin

1968 ◽  
Vol 46 (7) ◽  
pp. 1101-1104 ◽  
Author(s):  
C. M. Wong
Keyword(s):  
Infrared Spectra ◽  
Absolute Configuration ◽  
Optical Rotation ◽  
Specific Rotation ◽  
Stereospecific Synthesis ◽  
Specific Optical Rotation ◽  
Synthetic Compound ◽  
The Absolute ◽  
Hydrolysis Of ◽  
Absolute Stereochemistry

L-Tyrosine was converted stereospecifically to N-benzoyl-2-(p-methoxybenzyl)-3-hydroxy-4-cyanopyrrolidine (10) which had a specific optical rotation [Formula: see text]. Anisomycin was converted also to N-benzoyl-2-(p-methoxybenzyl)-3-hydroxy-4-cyanopyrrolidine (16) which had a specific rotation [Formula: see text]. The infrared spectra of the synthetic compound and the derivative of anisomycin were superimposable with each other. This result showed that the absolute configuration of the three asymmetric centers in (10) of synthetic origin were 2S, 3S, 4S, and those in (16) were 2R, 3R, 4R. Thus, anisomycin should have the absolute stereochemistry 2R, 3S, 4S as depicted in the structure (2). Hydrolysis of the hydroxy nitriles (8) and (10) gave an identical amide (3) which should have the absolute stereochemistry 2S, 3S, 4R as shown in structure (3).

Physicochemical Characterization of Organic Honeys Harvested in the North West Algerian Area

2020 ◽  
Vol 16 (9) ◽  
pp. 1421-1430
Author(s):  
Zidane Djelloul ◽  
Sid-Ahmed Benaoula ◽  
Abdeldjalil Daioui ◽  
Mohammed Z.E. El Mahi ◽  
Boumedien Meddah ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Water Content ◽  
Physicochemical Parameters ◽  
Free Acid ◽  
Optical Rotation ◽  
Physicochemical Characterization ◽  
Color Intensity ◽  
Specific Optical Rotation ◽  
North West ◽  
Organic Honey

Background: Consumers have become aware that the industrial methods of honey production have greatly affected the environment and product quality. Today, they want a reorientation of these production modes to obtain healthy and natural organic products. Objective: This study is conducted to evaluate, for the first time in Algeria, the physicochemical composition of organic honey’s harvest in the organic- North West Algerian area. Methods: Twenty-four samples of organic honey were harvested according to the organic beekeeping rules, by selected volunteer beekeepers in organic regions and hives, and then, they were extracted by the traditional method. Physicochemical parameters, such as pH, free acidity, density, electrical conductivity, diastase activity, carbohydrates, hydroxyl methyl furfural (HMF), water content, ash, color intensity and specific optical rotation were evaluated. Results: Mean values obtained for physicochemical parameters were: pH as 3-4.8, electrical conductivity as 0.123-1.180 mS/cm, free acid as 8-30 mEq/kg, diastase activity as 8.02-40.54 (Shade units), carbohydrates as 60.21-77.07%, sucrose as 1.04-8.97%, HMF quality as 4.67-27.63 mg/kg, water content as 14.2-19.0%, ash as 0.09-0.86%, color intensity ABS450 as 288-1467 mAU, color intensity (Pfund scale) as 0.30-137.34 mm and specific optical rotation at (-16.1)-(-3.8). The analysis indicated that organic honey samples grown in selected sites of our local area are of good quality. All of the obtained values were within the limits imposed by the present legislation (Codex Alimentarius). Conclusion: Analyzed honey samples are characterized as biological products of excellent quality with interesting nutritional properties.

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