Cellulose xanthate with a high degree of esterification

1980 ◽  
Vol 12 (3) ◽  
pp. 172-173
Author(s):  
V. A. Danilin ◽  
V. A. Terent'eva ◽  
N. A. Dorofeev ◽  
A. T. Serkov
Keyword(s):  
Cellulose Xanthate ◽  
Degree Of Esterification ◽  
High Degree

Spectrophotometic determination of the degree of esterification of cellulose xanthate in viscose

1971 ◽  
Vol 1 (5) ◽  
pp. 581-583 ◽  
Author(s):  
I. N. Kotomina ◽  
A. T. Serkov
Keyword(s):  
Cellulose Xanthate ◽  
Degree Of Esterification

Drug-Loaded Pectin Microparticles Prepared by Emulsion-Solvent Evaporation

2012 ◽  
Vol 506 ◽  
pp. 282-285 ◽  
Author(s):  
Pornsak Sriamornsak ◽  
S. Konthong ◽  
K. Burapapadh ◽  
Srisagul Sungthongjeen
Keyword(s):  
Crystalline State ◽  
Amorphous Solid ◽  
Solvent Evaporation ◽  
Drug Dissolution ◽  
Amorphous Solid Dispersion ◽  
Degree Of Esterification ◽  
X Ray ◽  
Evaporation Technique ◽  
Model Drug ◽  
High Degree

The aim of this study was to develop the pectin-based microparticles by emulsion-solvent evaporation technique. The effects of concentration and type of pectin and addition of glutaraldehyde on size, size distribution, drug crystalline state and drug dissolution from microparticles were investigated. The results showed that a model drug, indomethacin, could be encapsulated in microparticles. Higher molecular weight of pectin caused a larger in size of microparticles than the lower one. A high degree of esterification is preferred to stabilize the pectin microparticles. The powder x-ray diffractograms showed that all microparticles led to amorphous products while their physical mixture still showed the crystalline state of drug. Drug dissolution from the microparticles containing indomethacin and pectin was increased, resulting from the formation of an amorphous solid dispersion. Addition of glutaraldehyde, however, resulted in slower drug dissolution, compared to the formulations without glutaraldehyde or drug alone.

Degree of Esterification and Gelling Properties of Pectin Structure in Coffee Pulp

2016 ◽  
Vol 675-676 ◽  
pp. 11-14 ◽  
Author(s):  
Waleepan Rakitikul ◽  
Piyarat Nimmanpipug
Keyword(s):  
Density Functional ◽  
Gelling Agent ◽  
Generalized Gradient ◽  
Food Ingredient ◽  
Degree Of Esterification ◽  
Coffee Pulp ◽  
Scientific Investigations ◽  
Gelling Properties ◽  
The Difference ◽  
High Degree

Pectin is a high value functional food ingredient widely used as a gelling agent and stabilizer. The chemical structure of pectin has been the subject of scientific investigations for decades. Coffee producers remove beans; the other source of pectin, from coffee cherries is thrown away. Our study showed that pectin extracted from coffee pulp has high degree of esterification and methoxyl content of 93.75% and 7.87 respectively, which indicated good gelation properties. Nevertheless, here we were interested in the primary structure of pectin which is a complex polysaccharides that contains 1, 4-linked a-D-galactosyluronic acid (GalpA) residue. A theoretical dimension, density functional theory (DFT) with Generalized Gradient Approximation (GGA)/ BLYP functions, was utilized to study methylester substitution in pectin model compounds. For further discussion, the use of a COSMO model in different solvent showed the significant results in the difference torsion angle and HOMO diagram.

scholarly journals Purification of an Exopolygalacturonase fromPenicillium viridicatum RFC3Produced in Submerged Fermentation

2009 ◽  
Vol 2009 ◽  
pp. 1-8 ◽  
Author(s):  
Eleni Gomes ◽  
Rodrigo Simões Ribeiro Leite ◽  
Roberto da Silva ◽  
Dênis Silva
Keyword(s):  
Molecular Weight ◽  
Submerged Fermentation ◽  
Galacturonic Acid ◽  
Apparent Molecular Weight ◽  
Degree Of Esterification ◽  
Optimum Ph ◽  
The Stability ◽  
High Degree ◽  
Hydrolysis Of ◽  
Optimum Ph And Temperature

An exo-PG obtained fromPenicillium viridicatumin submerged fermentation was purified to homogeneity. The apparent molecular weight of the enzyme was 92 kDa, optimum pH and temperature for activity were pH 5 and 50–55∘C. The exo-PG showed a profile of an exo-polygalacturonase, releasing galacturonic acid by hydrolysis of pectin with a high degree of esterification (D.E.). IonsCa2+enhanced the stability of enzyme and its activity by 30%. TheKmwas 1.30 in absence ofCa2+and 1.16 mgmL−1in presence of this ion. In relation to theVmaxthe presence of this ion increased from 1.76 to 2.07 μmolmin−1mg−1.

Spectrophotometric determination of the degree of esterification of the cellulose xanthate in regenerated-cellulose film

1974 ◽  
Vol 6 (2) ◽  
pp. 213-214
Author(s):  
V. M. Irklei ◽  
V. G. Oleinik ◽  
A. S. Ryabchenko ◽  
S. G. Osinin ◽  
N. P. Chemeris ◽  
...  
Keyword(s):  
Spectrophotometric Determination ◽  
Cellulose Xanthate ◽  
Regenerated Cellulose ◽  
Cellulose Film ◽  
Degree Of Esterification ◽  
Regenerated Cellulose Film

scholarly journals Characterization of Pectin from Pulp and Peel of Ugandan Cooking Bananas at Different Stages of Ripening

2020 ◽  
Vol 9 (5) ◽  
pp. 67
Author(s):  
Diriisa Mugampoza ◽  
Samuel Gafuma ◽  
Peacekind Kyosaba ◽  
Richard Namakajjo
Keyword(s):  
Banana Peel ◽  
Equivalent Weight ◽  
Secondary Products ◽  
East African ◽  
Degree Of Esterification ◽  
Potential Source ◽  
Ripening Stages ◽  
Three Stages ◽  
High Degree

East African highland cooking bananas (EA-AAA) are a staple food and major source of calories for Ugandans. Cooking bananas are considerably wasted along the postharvest chain majorly due to poor handling and ripening. Banana waste is a potential source of secondary products such as pectin, wine, beer to mention a few. The aim of this study was to extract and characterize pectin from selected cooking bananas at various stages of ripening in order to assess their potential for commercial pectin production. Pectin was extracted from the bananas at five stages of ripening i.e. stages 0 (green maturity), 1, 2, 5 and 7. Extracted pectin at stages 2, 5 & 7 was characterized. Pectin yield from banana pulp decreased significantly with ripening (P<0.05) from between 18.1 to 22.65% at green maturity to between 0.65 to 1.28% at stage 7 of ripening. Pectin yield from banana peels was generally lower decreasing from between 5.34 to 6.61% at green maturity to between 1.01 to 1.38% at stage 7. The equivalent weight (1774 to 10144) of the pectin at selected stages of ripening was not significantly different (P>0.05) except individually. Methoxyl content was not significantly different among cultivars (P>0.05), however, it increased significantly through ripening stages (P<0.05). Anhydrouronic acid (AUA) ranged between 24.51 to 67.38% and increased with stage of ripening. AUA of pectin from pulp and peel did not differ significantly (P>0.05). The degree of esterification at each of the three stages was generally high (77 to 94%) implying high gelling power. These results showed that purity of pectin increases while yield decreases with ripening and that banana pectin has a high degree of esterification implying rapid set pectin. Thus, banana peel and pulp can be good sources of industrial pectin.

Change in polydispersity of degree of esterification of cellulose xanthate during the process of viscose ripening

1989 ◽  
Vol 21 (1) ◽  
pp. 24-29
Author(s):  
V. N. Drozdovskii ◽  
A. K. Stavtsov ◽  
V. M. Irklei ◽  
L. A. Mokrousova
Keyword(s):  
Cellulose Xanthate ◽  
Degree Of Esterification

Tissue section lifting for electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 86-87
Author(s):  
Adrian F. van Dellen
Keyword(s):  
Infectious Disease ◽  
Electron Microscopy ◽  
Tissue Culture ◽  
Organ System ◽  
Surrounding Tissue ◽  
Paraffin Sections ◽  
Surface Areas ◽  
Specific Determination ◽  
High Degree ◽  
Accuracy And Repeatability

The morphologic pathologist may require information on the ultrastructure of a non-specific lesion seen under the light microscope before he can make a specific determination. Such lesions, when caused by infectious disease agents, may be sparsely distributed in any organ system. Tissue culture systems, too, may only have widely dispersed foci suitable for ultrastructural study. In these situations, when only a few, small foci in large tissue areas are useful for electron microscopy, it is advantageous to employ a methodology which rapidly selects a single tissue focus that is expected to yield beneficial ultrastructural data from amongst the surrounding tissue. This is in essence what "LIFTING" accomplishes. We have developed LIFTING to a high degree of accuracy and repeatability utilizing the Microlift (Fig 1), and have successfully applied it to tissue culture monolayers, histologic paraffin sections, and tissue blocks with large surface areas that had been initially fixed for either light or electron microscopy.

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