China
Africa
Explore chapters and articles related to this topic
Thermal Treatments in Postcancer Care
Published in Paloma Tejero, Hernán Pinto, Aesthetic Treatments for the Oncology Patient, 2020
Peloid therapy consists of mud used therapeutically, as part of balneotherapy, or therapeutic bathing (Figure 34.3). Peloids consist of humus and minerals formed over many years by geological and biological, chemical, and physical processes. The water-soluble peat substances pass transdermally in sufficient quantities to induce a biological effect; the “human skin possesses a selective permeability for the water-soluble fulvic and ulmic acids and derivative fraction isolated as peat extract” [18]. The bacteriostatic and bactericidal activities of humic acid have a positive effect on mucous membranes [19]. The anti-inflammatory and antioxidant effects are key in postcancer patient treatment.
Organic Matter
Published in Michael J. Kennish, Ecology of Estuaries Physical and Chemical Aspects, 2019
Carbon and oxygen comprise more than 80% of the elemental content of fulvic and humic acids (Table 3). The carbon content of fulvic acids ranges from 40 to 50%, and the oxygen content from 44 to 50%. Humic acids, however, have a higher carbon content and lower oxygen content than fulvic acids, with carbon concentrations ranging from 50 to 60% and oxygen concentrations from 30 to 35%. Minor elements in both fractions include hydrogen (4 to 6%), nitrogen (<1 to 3% in fulvic acids; 2 to 6% in humic acids), and sulfur (0 to 2%). Humins have a similar elemental composition as humic acids.2
Ecotoxicology of Nanoparticles
Published in Suresh C. Pillai, Yvonne Lang, Toxicity of Nanomaterials, 2019
The presence of ligands can influence the dissolution. Sigg and Lindauer (2015) found that the presence of cysteine resulted in an initial increase of dissolved Ag while chloride and fulvic acids had little effect on the dissolution of AgNPs. Gunsolus et al. (2015) demonstrated the effects of humic acids on AgNP stability and fate. This provides further evidence for temporal variation in AgNP fate as humic acids increase in autumn when leaf litter is at its highest and geographical variation as heavily forested areas are likely to have higher humic acid concentrations. Humic acid is sometimes used in the production of nanoparticles and hence may encourage their formation in solution (Dubas & Pimpan, 2008; Gunsolus et al., 2015).
The toxicology of air pollution predicts its epidemiology
Published in Inhalation Toxicology, 2018
Andrew J. Ghio, Joleen M. Soukup, Michael C. Madden
Humic substances (HS) are ubiquitous, heterogeneous, amorphous, organic materials occurring in all terrestrial and aqueous environments including composts, sediments, peat bogs, coals, rivers, lakes, and oceans (Stevenson, 1985). The molecular weights for HS can range from a few hundred to millions of daltons. Chemically, they are a complex mixture of many different acids with prominent numbers of carboxylate and phenolate groups (Figure 1). HS include three different fractions: humic acid, fulvic acid and humin. Humic acid is the major extractable component of soil HS; it is insoluble in water under acidic conditions (pH <2) but soluble at higher pH values and dark brown to black in color. Fulvic acid is that fraction of HS soluble in water under all pH conditions and remains in solution after removal of humic acid by acidification; it is light yellow to yellow-brown in color. Humin is the fraction of HS that is not soluble in water at any pH value and is black in color.
Carbohydrate-derived fulvic acid wellness drink: its tolerability, safety and effect on disease markers in pre-ART HIV-1 positive subjects
Published in South African Family Practice, 2018
ME Botes, IS Gilada, JR Snyman, JPL Labuschagne
Humic substances are present wherever organic matter is decomposing.8–10 Humic substances can be defined as: ‘a general category of naturally occurring, biogenic, heterogeneous organic substances that can generally be characterized as being yellow to black in colour and of high molecular weight’. Humic substances can be subdivided into humic acid (HA), fulvic acid (FA) and humin. The average molecular weight of humic substances may range from 500 to 5 000 Da for FA and 3 000 to 1 000 000 Da for HA.9 These substances are characterised on the basis of their solubility in water as a function of pH. FA is the fraction that is soluble in water under all pH conditions. In general, FA is also lower in molecular size and weight and lower in colour intensity than the HA. The novel medicinal properties and applications of HA and FA have been researched over many decades for various applications.8,9
Microencapsulated soil conditioner with a water-soluble core: improving soil nutrition of crop root
Published in Journal of Microencapsulation, 2021
Wang Zuo, Wang Jincheng, Song Shiqiang, Rao Pinhua, Wang Runkai, Liu Shihui
As a type of soil conditioner, humic acid can influence the distribution, bioavailability and ultimate fate behaviour of nitrogen (Dong et al.2009). Fulvic acid (FA) is a type of purified humic acid and possesses water-soluble characteristic, which is analogous to be applied as a kind of fertiliser at present. Thus, microencapsulation of FA can simulate the packaging behaviour of water-soluble core materials and retain nitrogen performance.