Studies on the more soluble complexes of soil organic matter. 2. The composition of the soluble polysaccharide fraction

Abstract

141 together they may represent over 90 % of the products. There is present about 5 % of the epoxy acid, but little or no monoacyl esters and little or no coloured, resinous oils and the acids forming the scission products also appear to be absent or nearly so. 5. At all the above temperatures the products give evidence for the presence of #-ketonic acids and considerable volumes of carbon dioxide and water vapour are evolved. This apparent chain oxidation and degradation is regarded as being brought about by peroxides present in small amounts and formed from the unsaturated keto acids which are the initial products whose formation is probably catalysed by certain metals.

THE EFFECT OF TEMPERATURE ON THE MICROBIAL TRANSFORMATION OF [14C] GLUCOSE DURING INCUBATION IN SOIL

“…This also may increase the amount of substrate available for xylose synthesis. As xylose is a major sugar component in tropical soils (Forsyth, 1950;Oades, 1972) it would be interesting to compare the products of their microbial populations with those of British soils.…”

Boron in Water, Soils, and Plants

“…The suggested mechanism for the reaction of organic sites with boron is similar to the hydroxyl replacements suggested for clay minerals. Forsyth (1950) studied the composition of the soluble polysaccharide fraction of soil organic matter and found that upon hydrolysis various sugars such as galactose, glucose, mannose, arabinose, xylose, and glucoronic acid were produced. All these compounds meet the requirements for complex formation with boric acid, and most of them have been demonstrated to react with boric acid (Boeseken, 1949).…”

Chemical and Infrared Spectroscopic Studies of Fulvic Acid Fractions From a Podzol

“…They have high contents of uronic acids and bear considerable resemblances to pectic acid isolated from plant sources. Forsyth's 'polysaccharide' fractions, corresponding to F(2)C in the present work, also contained uronic acid residues, but he concluded that these were mainly glucuronic acid present as an aldobionic acid group, linked to glucose (Forsyth, 1950). In the present study, infrared spectroscopy and chemical analysis show that the uronic acids appear mainly in the F(2)D fractions and to a lesser degree in the F(2)C products.…”

“…Fractions A-D were then isolated by adsorption on charcoal and elution with A) 0.1 M hydrochloric acid, B) 90 per cent acetone, C) water and D) 0.1 M sodium hydroxide, as described by Forsyth ( 1947), except that fraction D was neutralized with hydrochloric acid, evaporated to about 500 cm3 and dialysed in Visking tubing against distilled water (5 x 5 litres), then freezedried.…”