humic acid

(redirected from fulvic acid)
Also found in: Dictionary, Thesaurus, Medical, Acronyms, Wikipedia.
Related to fulvic acid: Shilajit

humic acid

[′hyü·mik ′as·əd]
(organic chemistry)
Any of various complex organic acids obtained from humus; insoluble in acids and organic solvents.
References in periodicals archive ?
Based on the soil survey and the properties of fulvic acid, and assuming that the proposed mechanism of corrosion is responsible, the organic soil areas (Figure 3) listed in the soil database [3], highly ion-exchange prone soil areas (Figure 4), and highly acidic soil areas (Figure 5) were examined.
The FTIR spectra of fulvic acid samples were recorded on Bruker vector: 22 spectrophotometer using the potassium bromide (KBr) disc technique.
Fractionation of organic matter in soils of the forest shows a dynamic of organic matter despite the acidity of the medium, with the dominance of the stable fraction (humin), and also the presence of a high relative concentration of fulvic acids suggesting mobility of easily hydrolyzable components.
Considerably, higher quantity of fulvic acid from lignite coal was extracted by the simple method therefore, it may be used to optimise this source for fulvic acid.
1] soil) of 'mobile' and bound with calcium humic and fulvic acids in the 0-15 cm and 15-25 cm soil layers as influenced by tillage and the proportion of overwintering crops in the rotation (mean data 2004 and 2006) Treatment 0-15 cm HA1 FA1 FA1a HA2 FA2 Soil tillage systems (B) CT 0.
Effect of metal/fulvic acid mole ratios on the binding of Ni(II), Pb(II), Cu(II), Cd(II), and Al(III) by two well-characterized fulvic acids in aqueous model solutions.
Zuyi T, Shifang L, Jianjun Z, Fenling S (1997) Studies of thermal tansformations ofhumic and fulvic acids in soils.
Hence we tested four different HS preparations--two naturally occurring HA from the Altteich peatland in Germany, one fulvic acid (FA) preparation from a Finnish spruce forest and a synthetic HA-like polymer (caffeic acid oxidation product, KOP) for their influence on the lipopolysaccharide (LPS)-induced TNF-[alpha] release in human U937 cells.
The researchers determined the total phenolic content of the extracts using the Folin-Ciocalteu method: 24145 [+ or -] 1508 mg of fulvic acid per 100 g for the skins, and 425 [+ or -] 33 mg of fulvic acid per 100 g for the shells.
HA and fulvic acid are part of the naturally occurring dissolved organic carbon (DOC) component in water, and collectively are called humic substances.
Humic and fulvic acid are strong magnesium chelating agents, and it is known that Taq polymerase is magnesium dependent.