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Weight Organic Acids (weight + organic_acid)
Kinds of Weight Organic Acids Selected AbstractsElectrochemical Detection of Cadmium and Lead Complexes with Low Molecular Weight Organic AcidsELECTROANALYSIS, Issue 3-5 2009Jaklová Dytrtová Abstract The Cd and Pb complexes with oxalic (OA) and citric acid (CA) were detected in model and soil solutions using cyclic and stripping voltammetry. A mixed complex consisting of Cd, Pb, and OA was found; its peak potential varied from ,582.0 to ,542.5,mV (vs. Ag/AgCl/KCl(3,mol L,1)). For mixed complex formation, the presence of PbOH+ species and Cd2+ in oxalic acid solution was necessary. Only the ,simple' complexes of CA with Pb and Cd were found in the model solution. The existence of all investigated metal complexes is confined to neutral pH range. The mixed complex was also found in real soil solutions. [source] Capillary electrophoresis with capacitively coupled contactless conductivity detection for low molecular weight organic acids in different samplesJOURNAL OF SEPARATION SCIENCE, JSS, Issue 18 2007Wai Siang Law Abstract CE with capacitively coupled contactless conductivity detection (CE-C4D) was explored and validated for the identification and quantification of organic acids in various types of samples. The analyses were performed under optimized conditions, using a buffer system composed of 20 mM MES-histidine (His), pH 6.0, 0.1 mM CTAB, 0.025% HP-,-CD, and 10% methanol. The investigation included a study of the effects of buffer pH, concentration of CTAB, type and concentration of organic additives, on the migration behavior, resolution and selectivity of the organic acids. The intra- and interday RSDs (n = 6) obtained for migration time and peak area were typically in the range of 0.12,2% and 0.5,4%, respectively. Linearity, detection limits, and repeatability were evaluated. In order to evaluate the application potential of the developed method, real samples from different sources were analyzed. The results demonstrate that CE-C4D is a versatile tool for analyzing organic acids in beverages, Chinese herbal medicines (CHM) and plants as it allows for their detection, identification, and quantification. [source] Low molecular weight organic acids and fatty acids in root exudates of two Lupinus cultivars at flowering and fruiting stagesPHYTOCHEMICAL ANALYSIS, Issue 5 2001J. A. Lucas García Abstract Low molecular weight organic acids (LOAs) and fatty acids in root exudates of two lupin cultivars, Lupinus albus cv. Multolupa and L. luteus cv. Tremosilla, were determined at flowering and fruiting stages. LOAs were analysed by capillary electrophoresis. Acetic and citric acids were the most abundant, especially the latter in L. luteus at the flowering stage (5922.79,µg/g dry root). The significant decrease in acid content of both cultivars from flowering to fruiting stages was also striking. The highest levels of acetic acid were detected in L. luteus at fruiting stage (1542.03,µg/g dry root). The significant citrate production in L. luteus could be related to the low phosphorus concentration in the studied soils but not to proteoid roots, which were detected only in L. albus. The source of the LOAs detected in these exudates is also discussed, since they may be produced either by the plant or by the associated rhizobacteria. The profile of phospholipid fatty acids was determined by high-resolution GC. A high level of 18:2,6 (a fatty acid specific to fungi) was found in exudates of L. luteus (a mycorrhizal plant) in contrast to L. albus (a non-mycorrhizal plant). Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||