Oxidation Characteristics of Water Soluble Fractions of Agro-Stalks with Focus on Function of Reactive Inorganics

In order to deepen the understanding of the thermochemical behavior of reactive inorganics, which play an important role in slagging and fouling during combustion of agro-stalks, the oxidation behavior of the water-soluble fraction of corn stover, wheat straw and rice straw was examined using a simultaneous thermogravimetric analyzer. The oxidation characteristics were discussed in combination with elemental analysis of water-soluble fractions. Results showed that reactive inorganics elements account for 30–40% in water-soluble fractions of the three agro-stalks and carbon was oxidized at two separate stages. Four stages were found during oxidation of water-soluble fractions – (1) devolatilisation of organics (100‒400 °C); (2) oxidation of char (400–650 °C); (3) oxidation of char with melting of salts or decomposition of carbonate (650–800 °C); (4) vaporization of KCl (800–1000 °C). This work provides a base study for an optimized design of combustion for agro-stalks and pharmaceutical waste.

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Studies on Sulfhydryl Groups during Cell Division of Sea Urchin Egg

The Journal of General Physiology ◽

10.1085/jgp.45.3.427 ◽

1962 ◽

Vol 45 (3) ◽

pp. 427-438 ◽

Cited By ~ 17

Author(s):

Hikoichi Sakai

Keyword(s):

Cell Division ◽

Sea Urchin ◽

Soluble Fraction ◽

Water Soluble ◽

The Other ◽

Original Sample ◽

Water Soluble Fraction ◽

Sea Urchin Egg ◽

Soluble Fractions

The contractility of the thread model prepared from the KCl-soluble proteins of the egg and in vivo factors for the contraction are investigated in Hemicentrotus, Anthocidaris, and Pseudocentrotus eggs. The contractility of the thread model induced by metal ions or cystine changes during development in the characteristic pattern of high at the metaphase and low at the monaster and the interkinetic stages. The change in contractility is paralleled by the change in the —SH content of the protein. The water-soluble fraction of the eggs has activity in causing contraction of the thread model. This activity changes during development in the same way as the contractility itself. The contraction of the thread induced by the water-soluble fractions is accompanied by a decrease in the —SH content of the thread. The activity of the water-soluble fraction in inducing the contraction is proportional to its ability to decrease the number of —SH groups. On boiling, the activity is largely destroyed. The activity is due to two components, one being non-dialyzable and the other dialyzable. Separately each component has little effect, but when mixed, the activity of the original sample is completely restored.

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

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.117.4.600 ◽

1992 ◽

Vol 117 (4) ◽

pp. 600-606 ◽

Cited By ~ 52

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.

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Degradation of Pectic Polysaccharides in Pickled Green Olives

Journal of Food Protection ◽

10.4315/0362-028x-61.1.78 ◽

1998 ◽

Vol 61 (1) ◽

pp. 78-86 ◽

Cited By ~ 9

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.

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Tissue distribution of retinol and its metabolites after administration of double-labelled retinol

Biochemical Journal ◽

10.1042/bj1520099 ◽

1975 ◽

Vol 152 (1) ◽

pp. 99-104 ◽

Cited By ~ 13

Author(s):

P R Sundaresan ◽

G M Sundaresan

Keyword(s):

Vitamin A ◽

Soluble Fraction ◽

Liver Extract ◽

Total Radioactivity ◽

Retinyl Palmitate ◽

Light Petroleum ◽

Water Soluble ◽

Tissue Concentrations ◽

Water Soluble Fraction ◽

Soluble Fractions

The tissue concentrations and distribution of radioactivity present in retinol and its metabolites were investigated in vitamin A-deficient rats 24h after injection of physiological doses (10μg) of [6, 7-14C2, 11,12-3H2] retinol. The highest concentration of radioactivity was observed in the adrenals, followed by kidney, spleen, liver, intestine and blood. The total radioactivity was greatest in urine, followed in descending order by liver, kidney, blood and intestine. The 14C/3H ratios of crude light-petroleum extracts in the liver, intestines, lungs, heart and faeces were similar to the ratio of the injected retinol dispersion. However, the 14C/3H ratios in the adrenals, kidney, spleen, blood, brain and urine were quite different from that of injected retinol. Alumina chromatography of the kidney and intestinal extracts demonstrated that retinol and retinyl palmitate are the principal forms of vitamin A present. However, alumina chromatography of the liver extract did not reveal the presence of retinol but yielded a major compound with a low 14C/3H ratio. That this compound was not retinol was shown by its inability to react with ethanolic HC1 to yield anhydroretinol. The distribution of radioactivity in ether-soluble, acidic and water-soluble fractions of urine indicated that most of the radioactivity was present in the acidic and water-soluble fractions. The 14C/3H ratios in ether-soluble and acidic fractions were higher than that of injected retinol, whereas in the water-soluble fraction the ratio was similar to the injected material.

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COMPOSITION OF MUCOPROTEIN FRACTIONS FROM DUODENAL FLUID OF PATIENTS WITH CYSTIC FIBROSIS OF THE PANCREAS AND FROM CONTROLS

PEDIATRICS ◽

10.1542/peds.24.1.74 ◽

1959 ◽

Vol 24 (1) ◽

pp. 74-91

Author(s):

Zacharias Dische ◽

Paul di Sant'Agnese ◽

Charles Pallavicini ◽

Joshua Youlos

Keyword(s):

Cystic Fibrosis ◽

Sialic Acid ◽

Trichloroacetic Acid ◽

Soluble Fraction ◽

Water Soluble ◽

Carbohydrate Moiety ◽

Molar Ratio ◽

Water Soluble Fraction ◽

Duodenal Fluid ◽

Soluble Fractions

The mucus of the duodenal fluid of children contains a mixture of carbohydrateprotein complexes with the character of mucoids and glycoproteins. In duodenal fluids from patients with cystic fibrosis of the pancreas about one-third in controls about 90%, of the mucoid material is soluble in trichloroacetic acid (TCA). In duodenal fluids from patients with cystic fibrosis about one-third of the mucoid becomes denatured and insoluble in water when precipitated with an ethanolbenzene mixture. The TCA-soluble mucoid from patients with cystic fibrosis and controls was separated by fractionated ethanol precipitation into four fractions: three precipitating at 50% (A); 67% (B); and 90% (C), respectively; and one soluble in 90% ethanol. All four fractions contain as carbohydrate moiety a fucomucopolysaccharide. Fractions C and D contain about equivalent amounts of galactose and mannose and in patients with cystic fibrosis only one hexosamine (glucosamine) in demonstrable amounts. Fractions A and B contain glucosamine as well as galactosamine in comparable amounts, but the hexose present is galactose to an extent of more than 80%. The polysaccharides of all four mucoid fractions differ in their content of sialic acid. The least-soluble fraction A contains less of it than the more soluble fractions. The content of sialic acid in the mucopolysaccharide of the water-insoluble mucoid, and of the TCA-insoluble water-soluble fraction from pooled duodenal fluids of patients with cystic fibrosis, approaches that of fraction A and is lower than that of other fractions. The molar ratio of fucose to hexosamine in fraction A, and in the water-insoluble mucoid from patients with cystic fibrosis, is higher than in all fractions from controls.

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