Low-molecular-mass organic acids

Suzuki, Y., Determination of low-molecular-mass organic acids in fogwater by ion-exchange chromatography with automatic column switching, J. Chromatogr. A, 773, 123, 1997. 

Figure 1.5. Comparison of the influence of tannic acid and selected low-molecular-mass organic acids on surface charge of precipitation products of AI fomied after 40-day aging at room temperature and at an initial AI concentration of 1 x 10 mol L and an OH/Al molar ratio of 3.0. The initial concentrations of organic acids present during the precipitation of Al are (a) 1.0 x 10 mol L and Qj) 1.0 x 10 mol L . (From Kwong and Huang, 1981.)...

TABLE 1.4. Overall Diffusion Coefficients of Cd Release from Soils by 10 mol L Low-Molecular-Mass Organic Acids During a 0.25 to 1-h Reaction Period... 

Klampfl, C. W. and Buchherger, W., Determination of low-molecular-mass organic acids by capillary zone electrophoresis, TrAC—Trends in Analytical Chemistry, 16, 221-229, 1997. 

Some authors question the impact of pH and organic matter on mineralweathering reactions and indicate that organic substances may have distinct effects on weathering rates. Robert and Berthelin (1986) showed that complex-ing organic acids are only able to dissolve micas, but that acid compounds are able to induce the formation of vermiculite. Ochs (1996) demonstrated that humic substances were unable to weather significantly aluminium oxides while low molecular mass organic acids could. Moreover, Lolium multiflorum Lam. has... 

Excretion products of roots include a variety of low-molecular-mass organic acids (LMMOAs) such as acetic, butyric, oxalic, malic, propionic, succinic, citric, tartaric, and fumaric acid. The relative abundance of LMMOAs in the rhi-zosphere is both species and cultivar dependent (Marschner, 1995). 

Wang, M., Qu, R, Shan, X. Q., and Lin, J. M., Development and optimization of a method for the analysis of low-molecular-mass organic acids in plants by capillary electrophoresis with indirect UV detection, J. Chmmatogr. A, 989, 285-292, 2003. 

Hagberg, J. Analysis of low-molecular-mass organic acids using capillary zone electrophoresis-electrospray ionization mass spectrometry. J Chromatogr A, 988,127, 2003. 

Left) Xylulose and furfural from isomerization and dehydration reaction together with by-products derived from the condensation and the resinification reactions. (Right) Low-molecular-mass organic acids, giycolaidehyde or pyruvaldehyde, from different retro-aldol reactions [148]. 

Fulvic acid, a general term for a complex mixture of refractory polymeric compounds, is generally the dominant organic acid in soil solutions. A wide range of low-molecular-mass organic acids, most notably acetic, oxalic, and formic, are also present in soil solutions. The concentrations of these acids represent a dynamic balance between production and consumption by microbial processes. 

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