maleic-acid and tartaric-acid

Inhibiting sprouting of potatoes is an interesting subject needed for potato storage and industry. Sprouting degrades the quality of tuber along with releasing α-solanine and α-chaconine, which are harmful for health. Sprout suppressants, available in the market, are either costly or toxic to both health and environment. So, there is a need for developing countries to explore new sprouting suppressant compound which is cheap, non-toxic and reasonably efficient in comparison to commercial ones. We have established that simple maleic acid and L-tartaric acid are effective sprout suppressing agents. Both can hinder sprouting up to 6 weeks and 4 weeks post treatment respectively at room temperature in dark. These do not affect the quality parameters, retain the moisture content and maintain the stout appearance of the tubers along the total storage period. Thus maleic acid and L-tartaric acid would qualify as alternative, cheap, efficient sprout suppressant for potato storage and processing.

Topics: Food Storage; Maleates; Plant Tubers; Solanine; Solanum tuberosum; Tartrates

The characterization of the metabolites accumulated in the grapes of specific cultivars grown in different climates is of particular importance for viticulturists and enologists. In the present study, the metabolite profiling of grapes from the cultivars, Alvarinho, Arinto and Padeiro de Basto, of two Portuguese Controlled Denomination of Origin (DOC) regions (Vinho Verde and Lisboa) was investigated by gas chromatography-coupled time-of-flight mass spectrometry (GC-TOF-MS) and an amino acid analyzer. Primary metabolites, including sugars, organic acids and amino acids, and some secondary metabolites were identified. Tartaric and malic acids and free amino acids accumulated more in grapes from vines of the DOC region of Vinho Verde than DOC Lisboa, but a principal component analysis (PCA) plot showed that besides the DOC region, the grape cultivar also accounted for the variance in the relative abundance of metabolites. Grapes from the cultivar, Alvarinho, were particularly rich in malic acid and tartaric acids in both DOC regions, but sucrose accumulated more in the DOC region of Vinho Verde.

Topics: Amino Acids; Chromatography, Gas; Citric Acid; Fructose; Fruit; Fumarates; Geography; Glucose; Malates; Maleates; Mass Spectrometry; Metabolome; Metabolomics; Portugal; Principal Component Analysis; Species Specificity; Succinic Acid; Sucrose; Tartrates; Vitis

An ion-exclusion chromatographic method for the simultaneous determination of organic acids in rice wine was developed. An IC-Pak Ion Exclusion column (300 mm x 7.8 mm, 7 microm) was used at 50 degrees C. The mobile phases were H2SO4 (phase A) and acetonitrile (phase B) (98:2, v/v) at a flow rate of 0.5 mL/min. The gradient elution program was as follows: 0-40 min, 0.01 mol/L H2SO4 to 0.02 mol/L H2SO4; 40-50 min, 0.01 mol/L H2SO4. The injection volume was 10 microL. The detection wavelength was set at 210 nm. The results showed that oxalic acid, maleic acid, citric acid, tartaric acid, malic acid, ascorbic acid, succinic acid, lactic, fumaric acid, acetic acid, propionic acid, isobutyric acid and butyric acid were completely separated and determined in 30 min. The linear correlation coefficients were above 0.999 7 in the range of 0.001- 1.000 g/L. Under the optimized conditions, the recoveries of organic acids in rice wine were in the range of 93.4% - 103.8% with the relative standard deviations (RSDs, n = 5) of 0.1% - 1.5%. This method is feasible, convenient, fast, accurate and applicable for the quantitative analysis of the organic acids in rice wine.

Topics: Acids; Chromatography, Gel; Fumarates; Malates; Maleates; Oryza; Oxalic Acid; Tartrates; Wine

(1)H NMR spectrometry, FT-IR spectroscopy, as well as molecular modeling at the AM1 level and normal mode analysis were used to characterise the interactions and the formation of inclusion complexes between three organic acids: maleic, fumaric, L-tartaric acids and betaCD. In aqueous medium, the complexation was confirmed by (1)H NMR spectroscopy using two-dimensional technique. The stable geometries of the complexes were determined by molecular modeling. Experimental infrared frequencies were assigned on the base of the vibrational normal mode calculation at the fully optimized geometry for the inclusion complexes. All the results point out the presence of stable inclusion complexes between acids and betaCD at the solid state. These results show the double role of the acid. Correlated with the theoretical and experimental data previously obtained for the miconazole/CD/acids complexes, in function of both acids and CDs structures, the acids can either stabilize the complexes by formation of a multicomponent complex or form acid/CD inclusion complexes, hindering the guest inclusion.

Topics: beta-Cyclodextrins; Dicarboxylic Acids; Fumarates; Hydrogen Bonding; Magnetic Resonance Spectroscopy; Maleates; Miconazole; Models, Molecular; Pharmaceutical Vehicles; Spectroscopy, Fourier Transform Infrared; Tartrates; Thermodynamics

A reliable method for the simultaneous determination of oxalic, fumaric, maleic, and succinic acids in tartaric and malic acids for pharmaceutical use by reversed-phase ion-suppression high performance liquid chromatography is presented. HPLC was achieved on a Nova-Pak C18 column by isocratic elution using water adjusted to pH 2.10-2.15 with perchloric acid, and detection was by UV adsorption at a wavelength of 210 nm. This method was found to be superior to previous liquid chromatography as well as other classical assay, and to be an attractive choice for the analysis of these compounds.

Topics: Chromatography, High Pressure Liquid; Dicarboxylic Acids; Drug Contamination; Evaluation Studies as Topic; Fumarates; Hydrogen-Ion Concentration; Malates; Maleates; Oxalic Acid; Perchlorates; Reproducibility of Results; Succinic Acid; Tartrates

Guinea pigs received gentamicin to induce a profound hearing loss (61 dB auditory threshold shift at 18 kHz). Concomitant administration of maleic or tartaric acid dissolved in dimethyl sulfoxide (DMSO) significantly reduced the threshold shift to < 40 dB. The results have several important implications. First, they support the hypothesis of a free-radical mechanism of gentamicin toxicity since the protective compounds are metal chelators and scavengers. Second, they caution against these and similar chemicals, commonly found in drug preparations, as vehicles in tests of aminoglycoside toxicity. For example, a recent study by others describing attenuation of aminoglycoside ototoxicity by NMDA antagonists may have been influenced by the presence of maleate, tartrate and DMSO. Third, they suggest simple antioxidants as a potentially efficient and inexpensive clinical prophylaxis of aminoglycoside-induced hearing loss.

Topics: Animals; Anti-Bacterial Agents; Drug Evaluation, Preclinical; Excitatory Amino Acid Antagonists; Free Radical Scavengers; Gentamicins; Guinea Pigs; Hearing Loss; Male; Maleates; Receptors, N-Methyl-D-Aspartate; Tartrates

Investigations based on computer simulated distributions of histamine in blood plasma were recently devoted to the assessment of the roles of cysteine, aspartic and glutamic acids as possible adjuvants of zinc to favour histamine tissue diffusion through mixed-ligand coordination. Since all tissues contain at least one of the two enzymes required for the catabolism of histamine, any increase of its tissue diffusion is expected to result in an acceleration of its degradation, which may be of interest for the treatment of anaphylactic disorders. As an extension of these studies, the present paper first reports (i) an experimental investigation of the tendency of four dicarboxylic acids, namely malate, malonate, tartrate and maleate, to mixed-ligand coordination with zinc and histamine, (ii) computer-based potential effects to be expected from the association of these agents to zinc with respect to histamine tissue diffusion. Cell culture studies were then used to test simulation expectations. Two series of experiments involving successively human lymphocytes and a lymphoblastoid cell line (8866) have been carried out, which led to the following conclusions: (i) the hypothesis formerly put forward that cysteine could favour histamine tissue diffusion through mixed-ligand coordination with zinc has been validated on the two cell models, (ii) the formerly established suppressive role of histamine versus lymphocyte proliferation has clearly been confirmed, (iii) moreover, this suppressive effect has been shown to occur correlatively to histamine uptake by these cells, (iv) the four dicarboxylic acids, more especially tartric acid, proved effective as catalysts of the two above processes. Possible biomedical applications of these results are discussed.

Topics: Cell Line; Cysteine; Diffusion; Histamine; Humans; Lymphocyte Activation; Lymphocytes; Malates; Maleates; Malonates; Tartrates; Zinc

Topics: Fumarates; Maleates; Oxalates; Oxalic Acid; Tartrates