Ammonium Malate Research Articles

Leveraging organic acids in bipolar membrane electrodialysis (BPMED) can enhance ammonia recovery from scrubber effluents

While air stripping combined with acid scrubbing remains a competitive technology for the removal and recovery of ammonia from wastewater streams, its use of strong acids is concerning. Organic acids offer promising alternatives to strong acids like sulphuric acid, but their application remains limited due to high cost. This study proposes an integration of air stripping and organic acid scrubbing with bipolar membrane electrodialysis (BPMED) to regenerate the organic acids. We compared the energy consumption and current efficiency of BPMED in recovering dissolved ammonia and regenerating sulphuric, citric, and maleic acids from synthetic scrubber effluents. Current efficiency was lower when regenerating sulphuric acid (22 %) compared to citric (47 %) and maleic acid (37 %), attributable to the competitive proton transport over ammonium across the cation exchange membrane. Organic salts functioned as buffers, reducing the concentration of free protons, resulting in higher ammonium removal efficiencies with citrate (75 %) and malate (68 %), compared to sulphate (29 %). Consequently, the energy consumption of the BPMED decreased by 54 % and 35 % while regenerating citric and maleic acids, respectively, compared to sulfuric acid. Membrane characterisation experiments showed that the electrical conductivity ranking, ammonium citrate > ammonium malate > ammonium sulphate, was mirrored by the energy consumption (kWh/kg-N recovered) ranking, ammonium sulphate (15.6) < ammonium malate (10.2) < ammonium citrate (7.2), while the permselectivity ranking, ammonium sulphate > ammonium citrate > ammonium malate, aligned with calculated charge densities. This work demonstrates the potential of combining organic acid scrubbers with BPMED for ammonium recovery from wastewater effluents with minimum chemical input.

Biological Activity of Protic Ionic Liquids Based on Tris(2-hydroxyethyl)ammonium Salts and the Crystal Structure of Tris(2-hydroxyethyl)ammonium Malate

The antimicrobial and growth-stimulating activities of nine protic ionic liquids (PILs)—tris(2-hydroxyethyl)ammonium salts (protatranes) of cinnamic, benzoic, salicylic, oxalic, malonic, succinic, malic and citric acids—were investigated for the first time. It was found that tris(2-hydroxyethyl)ammonium salts of cinnamic, benzoic and malonic acids have a positive impact on seeds germination and growth characteristics of garden cress (Lepidium sativum L.) sprouts. All the investigated PILs exhibited selective activity against Staphylococcus aureus bacteria. PILs based on tris(2-hydroxyethyl)ammonium malate with the melting point of 41°C were isolated as crystals to perform a comparative study of the crystal structure by single-crystal X-ray diffraction. In contrast to cations in tris(2-hydroxyethyl)ammonium succinate, cations in malate have a tricyclic endo conformation that is most typical of tris(2-hydroxyethyl)ammonium salts.

Цифровое картографирование степени окультуренности пахотных почв Предсалаирской дренированной равнины

The article describes comparison of soil fertility indices (SFI) calculated for the ploughed layer of arable soils differing in soil organic matter (SOM) content: with high (5-8%) and medium (3-5%) SOM content. The studied soils were located on erosion-prone slope at different altitudes: soils with high SOM at 280-310 m, and soils with medium SOM at 190-280 m a.s.l. The study area was located in the interfluve area between the Irba and the Hiruzovka rivers in the Cis-Salair drained plain in the south-east of West Siberia. The soil types common there are Greyzemic Luvic Chernozems (Siltic, Aric, Pachic), Phaeozems (Siltic, Аric), Greyzemic Phaeozems Colluvic (Siltic, Taptomollic). The SFI were calculated in two steps. First, the relative indices (RI) for every agrochemical property, i.e. pHKCl, SOM, acetic acid extractable phosphorus (P) and exchangeable potassium (K), were calculated on the basis of respective minimal and optimal soil concentrations and crop requirements. Second, the SFI were calculated as sums of the relative indices divided by 4. The resultant SFI values were rated according to the scale where values below 0.4 indicate low fertility; values ranging 0.41-0.60 indicate moderate fertility, whereas values ranging 0.81-1.0 indicate high fertility. The digital maps of the RI and SFI were created using raster calculator in ENVI software, which allows performing mathematical operations with quantitative parameters of raster image pixels in GeoTIFF format. The values of relative indices in raster cells exceeding 1 (that is when factual content is higher than the optimal one) were substituted with 1 by specially developed program called ZChanger. Then the SFI map was created for erosion-risky slopes using as a basis the digital maps of the relative indices for pHKCl, SOM, P and K. Phosphorus was extracted by two different extragents, namely 0.5 М acetic acid (PAA) and 0.1 М ammonium malate (PAM). Soil fertility index was rated as medium irrespective of SOM content and soil type due to the high PAA content in soils with less SOM. It was found that when SFI were calculated using the data on easily available soil P, i.e. extracted with 0.015 М К2SO4 (PPS), then for most of the study area SFI can be rated as low, indicating the deficit of plant available phosphates in soils. High- and medium-SOM soils did not differ in рНKCL and PPS. The medium-SOM soils, such as agrochernozems, agro-grey and agro-dark-grey ones, had 1.7-2.2 lower SOM content as compared with the high-SOM soils such as agrochernozems. The reverse relation was found in labile P content: in soils with medium SOM level the PAA and PAM contents were 2 and 1.3 times higher than in high-SOM soils, respectively. In high-SOM agrochernozems PAA was lower than the optimal level (<20mg/100 g soil), while in medium-SOM soils it was higher. The PAM could be rated as medium. Exchangeable K in the arable soils was found to be unevenly distributed: in medium-SOM agrochernozems and agro-dark-grey soils exchangeable K was on average 1.2 times lower as compared with high-SOM agrochernozems, the difference with medium-SOM agro-grey soils being statistically not significant. Overall exchangeable K was lower than the optimal level (<30mg/100 g soil) Above-ground phytomass was found to be positively correlated with soil labile PPS (rs=0.41) and PAM (rs=0.33). The difference in aboveground phytomass produced by oats and peas mixture between high- and medium-SOM soils was not statistically significant.

Characterization of directed ammonium malate single crystals grown by Sankaranarayanan–Ramasamy method

Ammonium malate, an organic nonlinear optical single crystal, has been grown to a dimension of 50 mm length and 20 mm diameter by uniaxial solution-crystallization method of Sankaranarayanan–Ramasamy (SR). The growth conditions and experimental details of the grown crystals have been presented. The crystalline perfection of the grown crystals has been evaluated by high-resolution X-ray diffraction technique and the results reveal that the crystal quality of SR grown crystal is better than the conventional method grown crystal. The growth features in SR grown crystal have been analyzed by chemical etching technique and well-defined triangular etch hillocks have been observed. The mechanical property of the grown crystal has been analyzed by Vickers microhardness method and it reveals that the grown crystal is moderately harder material. Ammonium malate crystal possesses lower cut off wavelength at 230 nm. It enables good optical transmission of the second harmonic generation of Nd:YAG laser and other applications in the blue-violet region. The second harmonic generation of the grown crystal has been confirmed by the Kurtz powder technique.

Effect of ammonium malate on growth rate, crystalline perfection, structural, optical, thermal, mechanical, dielectric and NLO behaviour of ammonium dihydrogen phosphate crystals

The effect of ammonium malate on the growth rate, structural, optical, thermal, mechanical, dielectric properties, crystalline perfection and second harmonic generation (SHG) efficiency of ammonium dihydrogen phosphate single crystals grown by the slow cooling method has been investigated. The lattice parameters of the grown crystals were obtained by the single-crystal X-ray diffraction analysis. Fourier transform infrared studies confirm the functional groups of the crystals. UV–vis study shows that the transparency is increased much by the dopant. Thermal analysis was performed to study the thermal stability of the grown crystals. Vickers hardness measurements reveal the higher hardness of the doped crystals. Low dielectric losses were observed from the dielectric measurements for the doped ADP crystals. The high-resolution X-ray diffraction studies show that the crystalline perfection of the crystals is good. The relative SHG efficiency measurements revealed that the dopant has enhanced the efficiency.

Growth and characterization of an organic NLO material ammonium malate

Second harmonic generation organic material, ammonium malate (AM), has been synthesized and grown as quality single crystals by the slow evaporation technique. As-grown crystals were characterized by X-ray powder diffraction (XRPD) and Fourier transforms – nuclear magnetic resonance (FT-NMR). The optical band gap was estimated for AM crystal using UV–vis study. Measuring transmittance of AM permitted the calculation of the refractive index n; the extinction coefficient K and both the real ε r and imaginary ε i components of the dielectric permittivity as functions of photon energy. Density functional theory at the HF/3-21 G (d, p) level has been used to calculate the first-order hyperpolarizability of AM. The second harmonic conversion efficiency of AM was determined using Kurtz powder technique; it was observed to be greater than that of KDP. The mechanical anisotropy property of the grown crystals was studied using Vickers microhardness tester at different planes. The photoluminescence study is also analyzed. The growth features were analyzed by wet chemical etching studies. The factor group analysis was carried out for AM which predicts that there are 132 vibrational optical modes.

Synthesis, crystal growth, structural, optical, thermal and mechanical properties of novel organic NLO material: Ammonium malate

Ammonium malate (AM), an organic nonlinear optical material, has been synthesized and single crystals, with dimensions up to 38×35×27 mm 3, have been grown from aqueous solution. The crystal structure of AM has been determined, and it belongs to the non-centro symmetric space group Cc. The structural perfection of the grown crystals has been analysed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. Fourier transform infrared (FTIR) spectroscopic studies were also performed for the identification of different modes present in the compound. The UV–vis transmission spectrum has been recorded in the range 200–1100 nm. The second harmonic conversion efficiency of AM was determined using the Kurtz powder technique; it was observed to be greater than that of KDP. Thermal behaviour of AM was studied by TG and DTA. The dielectric and mechanical behaviour of the specimen was also studied.

Determination of C/N Ratios Required for De-Repression of Nitrogenase in Rhodobacter capsulatus

Abstract Phototrophic continuous and batch cultures of Rhodobacter capsulatus were employed to identify the C/N ratio above which nitrogenase is de-repressed. The cultures were grown with limiting amounts of ammonium as source of bound nitrogen and with ʟ-lactate or ʟ-malate as sources of carbon and reducing equivalents. De-repression of nitrogenase was determined on the basis of the occurrence of dinitrogen fixation, acetylene reduction and nifH promoter activities as well as on the basis of hydrogen evolution and nitrogenase poly­ peptides. In continuous culture, cells started to fix dinitrogen, to reduce acetylene, to activate the nifH promoter and to form nitrogenase polypeptides, when consuming lactate per ammonium at a C/N ratio of about 6 (this ratio represents the number of C and N atoms consumed). With malate as carbon source all of the activities becam e detectable above a C/N ratio of about 8. Essentially the same C/N ratios were determined with batch cultures for the occurrence of N -limitation of growth and hydrogen evolution. The experimentally deter­mined C/N ratios for nitrogenase de-repression essentially agreed with C/N ratio of 5.8 and 7.8 calculated for the assimilation of ammonium and either lactate or malate, into biomass of an elemental com position of CH1.83N0.183O0.5-This means that the occurrence of N -limitation and nitrogenase de-repression is defined by a threshold C/N ratio required for biomass production. As experimentally and theoretically shown, this ratio depends on the reduction state of the carbon source. It is concluded that the C/N ratio of nutrient consumption represents an intracellular signal which is directly translated into nitrogenase de-repression.

A possible route for the formation of protoprotein and its microspheres from primitive gases under possible prebiotic conditions

In this study, a possible reaction pathway for the formation of protein-like copolyamino acids from gaseous starting materials is presented. The sequence of the reaction pathway is composed of four steps. These are a) formation of fumaronitrile, b) hydrolysis of fumaronitrile to thermal precursors of aspartic acid such as ammonium fumarate or malate, c) thermal copolycondensation of the precursors of aspartic acids with various amino acids (s), and d) formation of microspheres from the copolyamino acids. The steps b), c) and d) were demonstrated experimentally in this study. The materials and the conditions used in this study could be regarded as prebiological. The thermal copolycondensation is also a convenient synthetic method of aspartic acid containing copolyamino acids.

Oxaloacetate and Malate Transport by Plant Mitochondria

The permeability of mitochondria from pea (Pisum sativum L. var Kleine Rheinländerin) leaves, etiolated pea shoots, and potato (Solanum tuberosum) tuber for malate, oxaloacetate, and other dicarboxylates was investigated by measurement of mitochondrial swelling in isoosmolar solutions of the above mentioned metabolites. For the sake of comparison, parallel experiments were also performed with rat liver mitochondria. Unlike the mammalian mitochondria, the plant mitochondria showed only little swelling in ammonium malate plus phosphate media but a dramatic increase of swelling on the addition of valinomycin. Similar results were obtained with oxaloacetate, maleate, fumarate, succinate, and malonate. n-Butylmalonate and phenylsuccinate, impermeant inhibitors of malate transport in mammalian mitochondria, had no marked inhibitory effect on valinomycin-dependent malate and oxaloacetate uptake of the plant mitochondria. The swelling of plant mitochondria in malate plus valinomycin was strongly inhibited by oxaloacetate, at a concentration ratio of oxaloacetate/malate of 10(-3). From these findings it is concluded: (a) In a malate-oxaloacetate shuttle transferring redox equivalents from the mitochondrial matrix to the cytosol, malate and oxaloacetate are each transported by electrogenic uniport, probably linked to each other for the sake of charge compensation. (b) The transport of malate between the mitochondrial matrix and the cytosol is controlled by the oxaloacetate level in such a way that a redox gradient can be maintained between the NADH/NAD systems in the matrix and the cytosol. (c) The malate-oxaloacetate shuttle functions mainly in the export of malate from the mitochondria, whereas the import of malate as a respiratory substrate may proceed by the classical malate-phosphate antiport.

Production of the reserve material poly-β-hydroxybutyrate and its function in Azospirillum brasilense Cd

Azospirillum brasilense Cd was grown in ammonium–malate mineral salts medium in batch culture and in chemostat continuous culture. It was found that poly-β-hydroxybutyrate synthesis was favored under oxygen limitation in chemostat culture and under high C/N ratios towards the end of exponential growth in batch culture. The degradation and synthesis of poly-β-hydroxybutyrate under starvation conditions occurred in a biphasic pattern and was affected by the poly-β-hydroxybutyrate content of the cells. During a 7-day incubation period in phosphate buffer, the survival and respiration rate of bacteria containing about 40% poly-β-hydroxybutyrate (dry weight) were higher than those of cells containing about 5% poly-β-hydroxybutyrate. Polymer-rich cells fixed atmospheric nitrogen in the absence of exogenous carbon and combined nitrogen. Biphasic nitrogenase activity was observed during starvation. When nitrogenase activity was high, hydroxybutyrate dehydrogenase activity was low and vice versa. Aerotactic response was higher in polymer-rich cells. In the presence of stress factors such as ultraviolet irradiation, dessication, and osmotic pressure poly-β-hydroxybutyrate-poor cells died more rapidly than poly-β-hydroxybutyrate-rich cells.

Transport of phosphate analogues in rat-liver mitochondria.

The swelling of rat liver mitochondria has been studied in isotonic ammonium salts of phosphate, thiophosphate, monofluorphosphate, difluorphosphate or in isotonic ammonium malate induced by low concentrations of the mentioned anions. The data lead to the following conclusions. 1. Phosphate, thiophosphate, and monofluorphosphate are taken up by the mitochondria, whereas difluorphosphate is not, indicating that the substrate of the transporter represents the divalent anion HPO24- and not H2PO4-. 2. Thiophosphate, monofluorphosphate and phosphate, but not difluorphosphate induce the swelling of mitochondria in isotonic ammonium malate, only after a lag phase. The length of the lag phase depends on the concentration of inducing anion and pH. This phenomena cannot be explained by the current concept of two independent phosphate-transporting systems in mitochondria.

Optical second harmonic generation in organic crystals: urea and ammonium-malate

Optical second harmonic generation (SHG) has been investigated in single-crystals of urea and ammonium-malate (AM). Phase match angle, refractive indices, and all nonvanishing coefficients of the nonlinear susceptibility tensor have been measured. A comparison to KDP shows, that AM is comparable to KDP, urea much more efficient in SHG than KDP, The measurements were performed with a flash-lamp pumped dye laser which could be tuned from 480 nm to 640 nm using different dyes (mainly coumarins and rhodamines). The crystals were gro-wn from solution and had a typical size of 5 x 10 x 10 mm3 in the case of urea and 15 x 15 x 10 mm3 in the case of AM, respectively, after cutting and polishing. They could be rotated in the laser beam around a horizontal and a vertical axis, so that all desired crystal directions for the incident polarization could be achieved. For the detection of the second harmonic signal served a solarblind photomultiplier with CST.e photocathode, the signal of which could either be displayed on an oscilloscope or be averaged by a gated integrator.

Optical second harmonic generation in ammonium malate

Second harmonic generation in ammonium malate has been investigated in a wavelength region between 492 nm (short wavelength limit of the harmonic beam at 246 nm) and 640 nm. Phase match angle, refractive indices and all coefficients of the nonlinear susceptibility tensor have been measured; several possibilities for phase matching are discussed.

The effect of vitamin E deficiency on permeability of mitochondria for phosphate.

We have investigated whether the earlier-found decreased unsaturation in mitochondrial membranes in vitamin E deficiency affects the permeability properties of mitochondria. The iso-osmotic swelling technique was used as a measure for the rate of uptake of substrates by these organelles. A significantly slower uptake could be observed of ammonium malate in the presence of phosphate and of ammonium phosphate. These changes in membrane permeability might give a clue to the mechanism of some metabolic abnormalities as seen in vitamin E deficiency in relating these abnormalities to specific membrane functions, e.g. an affection of carriers; for instance the phosphate carrier.

Growth and Plating of Cell Suspension Cultures of Datura innoxia

AbstractSuspension cultures of Datura innoxia Mill, were successfully grown on a modified Murashige and Skoog medium with 2,4–D, NAA or BAP as growth substances, provided the micronutrient levels were reduced to 1/10. Normal amounts of micronutrients were toxic. Attempts to identify the toxic elements did not succeed.Cultures grew exponentially on a shaker at 27°C in the light. Their doubling times varied from 1.1 days on 2,4–D (10–6M) or NAA (10−5M)+ 1 g/1 casein hydrolysate to 2.7 days on BAP (3 × 10−7M) and 5.1 days on supraoptimal levels of 2,4‐D (10−5M). Cultures grew on NH4+‐N alone (from ammonium malate) or on NO3−‐N alone. Dry weight yield was proportional to the amount of nitrate‐N added (47 mg/mg N).Filtered suspension cultures containing single cells (plating cultures) could be grown in agar in petri dishes when NAA or 2,4‐D were used as growth substances. Cells grew at densities above 500 units/ml in the agar. Most colonies grew from cell aggregates but division in single cells was observed. The highest plating efficiency was about 50% on 10−6 M 2,4‐D + 1 g/1 casein hydrolysate.

Inhibition of anion transport across the mitochondrial membrane by amytal

It has been found that amytal competitively inhibits succinate (+ rotenone) oxidation by intact uncoupled mitochondria. Similar results were obtained in metabolic state 3, the K i value being 0.45 mM. Amytal did not effect succinate oxidation by broken mitochondria and submitochondrial particles (at a concentration which inhibited succinate oxidation by intact mitochondria). Amytal inhibited the swelling of mitochondria suspended in ammonium succinate or ammonium malate but was without effect on the swelling of mitochondria in ammonium phosphate and potassium phosphate in the presence of valinomycin+carbonylcyanide p-trifluoromethoxyphenylhydrazone. Using [ 14C] succinate and [ 14C] citrate it has been shown that amytal inhibited the succinate/succinate, succinate/P i, succinate/malate, and citrate/citrate and citrate/malate exchanges. Amytal inhibited P i transport across mitochondrial membrane only if preincubated with mitochondria. Other barbiturates: phenobarbital, dial, veronal were found to inhibit [ 14C]succinate/anion (P i, succinate, malonate, malate) exchange reactions in a manner similar to amytal. It is concluded that barbiturates non-specifically inhibit the dicarboxylate carrier system, tricarboxylate carrier and P i translocator. It is postulated that the inhibition of succinate oxidation by barbiturates is caused mainly by the inhibition of succinate and P i translocation across the mitochondrial membrane.

The transport of sulphate and sulphite in rat liver mitochondria.

1. The mechanism of sulphite and sulphate permeation into rat liver mitochondria was investigated. 2. Extramitochondrial sulphite and sulphate elicit efflux of intramitochondrial phosphate, malate, succinate and malonate. The sulphate-dependent effluxes and the sulphite-dependent efflux of dicarboxylate anions are inhibited by butylmalonate, phenylsuccinate and mersalyl. Inhibition of the phosphate efflux produced by sulphite is caused by mersalyl alone and by N-ethylmaleimide and butylmalonate when present together. 3. External sulphite and sulphate cause efflux of intramitochondrial sulphate, and this is inhibited by butylmalonate, phenylsuccinate and mersalyl. 4. External sulphite and sulphate do not cause efflux of oxoglutarate or citrate. 5. Mitochondria swell when suspended in an iso-osmotic solution of ammonium sulphite; this is not inhibited by N-ethylmaleimide or mersalyl. 6. Low concentrations of sulphite, but not sulphate, produce mitochondrial swelling in iso-osmotic solutions of ammonium malate, succinate, malonate, sulphate, or phosphate in the presence of N-ethylmaleimide. 7. It is concluded that both sulphite and sulphate may be transported by the dicarboxylate carrier of rat liver mitochondria and also that sulphite may permeate by an additional mechanism; the latter may involve the permeation of sulphurous acid or SO(2) or an exchange of the sulphite anion for hydroxyl ion(s).

The inhibition of mitochondrial dicarboxylate transport by inorganic phosphate, some phosphate esters and some phosphonate compounds.

1. P(i) competitively inhibited succinate oxidation by intact uncoupled mitochondria in the presence of sufficient N-ethylmaleimide to block the phosphate carrier, with a K(i) of 2.5mm. 2. Of a large number of phosphate esters and phosphonate compounds, phenyl phosphate and phenylphosphonate were found to inhibit competitively uncoupled succinate oxidation by intact but not broken mitochondria. By comparison, benzoate was a relatively weak competitive inhibitor of succinate oxidation by intact mitochondria but a relatively potent inhibitor of succinate dehydrogenase. 3. Phenyl phosphate and phenylphosphonate were non-penetrant, and inhibited P(i)-dependent swelling of mitochondria suspended in isosmolar ammonium malate in a manner non-competitive with P(i). The inhibitors did not affect mitochondrial swelling when tested with P(i) alone. 4. It is concluded that: (i) phenyl phosphate and phenylphosphonate behaved as non-penetrant analogues of P(i), since their inhibitory properties were in strict contrast with those of benzoate; (ii) phenyl phosphate and phenylphosphonate interacted with the dicarboxylate carrier but not with the phosphate carrier; (iii) P(i) was effective as a competitive inhibitor of succinate oxidation because of its being either an alternative substrate for the dicarboxylate carrier or competitive with succinate for the intramitochondrial cations as proposed by Harris & Manger (1968).

Inhibition by tannic acid of succinate and malate translocation across the mitochondrial membrane

The effect of tannic acid on succinate oxidation and on succinate and malate translocation has been studied in rat liver mitochondria. Tannic acid inhibits succinate oxidation in mitochondria but not in submitochondrial particles. The inhibition of succinate oxidation appears as competitive by using the double reciprocal plot and as partially competitive by using the Dixon plot. Tannic acid inhibits the swelling of mitochondria on the presence of ammonium succinate or ammonium malate and the valinomycin-induced swelling with succinate as accompanying anion. It is concluded that tannic acid inhibits succinate oxidation by preventing the operation of the carrier of dicarboxylic acids on the mitochondrial membrane. The reported evidence indicates that tannic acid induces a confonnational change reducing the affinity of the carrier for succinate.