scholarly journals Seasonal variation of high-molecular-weight compounds in the water-soluble fraction of organic urban aerosols

2005 ◽  
Vol 110 (D23) ◽  
Author(s):  
V. Samburova ◽  
S. Szidat ◽  
C. Hueglin ◽  
R. Fisseha ◽  
U. Baltensperger ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Seasonal Variation ◽  
High Molecular Weight ◽  
Soluble Fraction ◽  
Water Soluble ◽  
Urban Aerosols ◽  
Water Soluble Fraction

Functional group analysis of high-molecular weight compounds in the water-soluble fraction of organic aerosols

2007 ◽  
Vol 41 (22) ◽  
pp. 4703-4710 ◽  
Author(s):  
Vera Samburova ◽  
Tatiana Didenko ◽  
Erast Kunenkov ◽  
Christian Emmenegger ◽  
Renato Zenobi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Functional Group ◽  
Soluble Fraction ◽  
Group Analysis ◽  
Organic Aerosols ◽  
Water Soluble ◽  
Water Soluble Fraction ◽  
Functional Group Analysis

scholarly journals Molecular Weight and Degree of Methoxylation in Cell Wall Polyuronide during Softening in Pear and Apple Fruit

1992 ◽  
Vol 117 (4) ◽  
pp. 600-606 ◽  
Author(s):  
H. Yoshioka ◽  
K. Aoba ◽  
Y. Kashimura
Keyword(s):  
Molecular Weight ◽  
Cell Wall ◽  
Cell Walls ◽  
Soluble Fraction ◽  
Apple Fruit ◽  
Water Soluble ◽  
Pear Fruit ◽  
Water Soluble Fraction ◽  
High Degree ◽  
Soluble Fractions

The concentrations of water-soluble polyuronides in apples [Malus domestica Borkh.) and pears (Pyrus communis L.) increased, but those of EDTA- and HCl-soluble polyuronides decreased during softening. Total polyuronide content decreased slightly during softening in both fruits. Depolymerization of polyuronides was observed only in the water-soluble fraction in pear fruit during softening, concomitant with an increase in polygalacturonase (PG) activity. No detectable depolymerization was observed in any of the polyuronide fractions during softening of apple fruit nor was any PG activity detected. The polyuronide fractions extracted from pear and apple cell walls contained various amounts of methoxyl groups. Polyuronides with a high degree of methoxylation were preferentially lost from EDTA- and HCl-soluble polyuronides during softening of both fruit. The water-soluble polyuronide had a lower degree of methoxylation than those lost in the EDTA- and HCl-soluble fractions. These results suggest de-esterification of polyuronides with a high degree of methoxylation rather than the depolymerization of polyuronides in the solubilization of polyuronides during ripening of apples and pears.

Degradation of Pectic Polysaccharides in Pickled Green Olives

1998 ◽  
Vol 61 (1) ◽  
pp. 78-86 ◽  
Author(s):  
CORAL SÁNCHEZ-ROMERO ◽  
RAFAEL GUILLÉN ◽  
ANTONIA HEREDIA ◽  
ANA JIMÉNEZ ◽  
JUAN FERNÁNDEZ-BOLAÑOS
Keyword(s):  
Molecular Weight ◽  
Potassium Hydroxide ◽  
Soluble Fraction ◽  
Water Soluble ◽  
Low Molecular Weight ◽  
Pectic Polysaccharides ◽  
Water Soluble Fraction ◽  
Molecular Weights ◽  
Extraction Agent ◽  
Soluble Fractions

The changes that occur in the pectic fractions in the cell wall of olives of the Manzanilla variety (Olea europaea pomiformis) during processing (initial treatment at high pH and subsequent lactic fermentation) have been researched. After studying various conditions for fractionating the pectic polysaccharides, the most adequate were chosen, involving sequential extraction with water, imidazole-hydrochloric acid buffer, sodium carbonate, 1 M potassium hydroxide, and 4 M potassium hydroxide. In the unprocessed fruit, the fractions studied consist mainly of high-molecular-weight acidic polysaccharides (70 to 250 kDa): homogalacturonans, rhamnogalacturonans, and branched arabinans. These were found in different proportions depending on the extraction agent used. At the same time, significant amounts of relatively low-molecular-weight (10 to 10.5 kDa) neutral branched arabinans were found in the water-soluble fraction. As a result of the processing, changes occurred in the proportions of the different groups of polysaccharides in accordance with changes in their solubility characteristics. These changes were reflected in the processed fruit by (i) an increase in the neutral branched arabinans in the water-soluble fraction due to the increased presence of such polysaccharides originally found in the carbonate and 4 M KOH-soluble fractions; (ii) an increase in homogalacturonans and rhamnogalacturonans, without significant changes in molecular weights, in the imidazole-soluble fraction as a result of the increased presence of corresponding polysaccharides originally found in the carbonate-soluble and water-soluble fractions; (iii) a substantial increase in uronic acids in the 1 M potassium hydroxide-soluble fraction, preferentially as low-molecular-weight polysaccharides; and (iv) a solubilization of arabinans in the 4 M potassium hydroxide-soluble fraction.

Impact of Rice Flour Cold-Water-Soluble Fraction Removal on Gelatinization and Pasting Properties

2014 ◽  
Vol 91 (5) ◽  
pp. 473-481 ◽  
Author(s):  
Guiai Jiao ◽  
Xiangjin Wei ◽  
Gaoneng Shao ◽  
Lihong Xie ◽  
Zhonghua Sheng ◽  
...  
Keyword(s):  
Cold Water ◽  
Soluble Fraction ◽  
Rice Flour ◽  
Pasting Properties ◽  
Water Soluble ◽  
Water Soluble Fraction

FRACTIONATION OF LIVETIN AND THE MOLECULAR WEIGHTS OF THE α- AND β-COMPONENTS

1957 ◽  
Vol 35 (4) ◽  
pp. 241-250 ◽  
Author(s):  
W. G. Martin ◽  
J. E. Vandegaer ◽  
W. H. Cook
Keyword(s):  
Light Scattering ◽  
Soluble Protein ◽  
Soluble Fraction ◽  
Egg Yolk ◽  
Water Soluble ◽  
Water Soluble Fraction ◽  
Molecular Weights ◽  
Water Soluble Protein ◽  
Hen Egg Yolk ◽  
Hen Egg

Livetin, the major water-soluble protein of hen egg yolk, was found to contain three major components having mobilities of −6.3, −3.8, and −2.1 cm.2 sec.−1 volt−1 at pH 8, µ 0.1, and these have been designated α-, β-, and γ-livetin respectively. The α- and β-livetins were separated and purified electrophoretically after removal of γ-livetin by precipitation from 37% saturated ammonium sulphate or 20% isopropanol. The α-, β-, and mixed livetins resembled pseudoglobulins in solubility but γ-livetin was unstable and this loss of solubility has, so far, prevented its characterization. Molecular weights determined by light scattering, osmotic pressure, and Archibald sedimentation procedure yielded respectively: 8.7, 7.8, and 6.7 × 104 for α-livetin, and 4.8, 5.0, and4.5 × 104 for β-livetin. Under suitable conditions of sedimentation and electrophoresis, egg yolk has been shown to contain three components having the same behavior as the three livetins of the water-soluble fraction.

Effect of High Molecular Weight Water-Soluble Chitosan on the Trabecular Bone and Thickness in Ovariectomized Rats

2007 ◽  
Vol 29 (3-4) ◽  
pp. 439-449 ◽  
Author(s):  
Han-Jung Chae ◽  
Geun-Youn Lee ◽  
Sun-Kyung Yang ◽  
Do-Sung Kim ◽  
Ki-Jung Yun ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Trabecular Bone ◽  
High Molecular Weight ◽  
Water Soluble ◽  
Ovariectomized Rats
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