Malonic Acid Research Articles

Black Rice Anthocyanins as An Effective Antioxidant of Inhibition of Oil Oxidative Based on Molecular Modification.

This present work investigated the influence of black rice anthocyanins as antioxidants on the oxidation stability of oil. Malonic acid, succinic acid and succinic anhydride were grafted on black rice anthocyanins through acylation method to improve their antioxidant activity in oil. The results from fourier transform infrared spectroscopy (FTIR) showed new absorption peaks near 1744 cm -1 and 1514 cm -1 , which implied that malonic acid, succinic acid and succinic anhydride grafted on the -OH of glucoside and rutinoside through esterification reaction and resulted that the polarity of these were reduced. Total content of anthocyanin (TAC) decreased to 166. 3 mg/g, 163.7 mg/g and 150.2 mg/g, respectively after modification with succinic acid, malonic acid and succinic anhydride. Compared with native anthocyanins, the acylation of black rice anthocyanins partially reduced its antioxidant activity. In addition, DPPH clearance of molecular modified anthocyanins decreased to 62.6% (San-An). As revealed in the oil stability through the determination of primary oxidation products (PV) and secondary oxidation products (p-AV), Sa-An, Ma-An and San-An showed stronger antioxidant activity in Schaal oven accelerated oxidation test during 12 days than native black rice anthocyanin in both corn oil and flaxseed oil. Molecular modified black rice anthocyanins are expected to be used as colorants, antioxidants, etc. in oil-rich food.

Sustainable Approach for Utilization of Mango Peel Wastes for Pectin Extraction by Natural Deep Eutectic Solvents

Sequential ultrasound‐ and microwave‐assisted natural deep eutectic solvents (NADES) were used for the extraction of pectin from mango peels in this study. The two different NADES composed of proline: malonic acid (Pro: MA) and choline chloride: tartaric acid (ChCl: TA) which resulted in higher pectin yield were selected for further optimization studies. The processing conditions such as sonication duration, microwave intensity, microwave processing duration, and liquid–solid ratio were optimized using Box–Behnken design. The optimized conditions are sonication duration (7.5 min), microwave intensity (40 W/g), microwave processing duration (5 min), and liquid–solid ratio (65%). The physicochemical and technofunctional properties of pectin extracted using NADES were compared with conventional acid–extracted pectin. The moisture and ash content of NADES‐extracted pectin were within the specified limit provided by the International Pectin Producers Association. The NADES‐based extracted pectin contains galacturonic acid content higher than 65%, as mentioned by the Joint FAO/WHO Expert Committee on Food Additives and the European Commission. The higher anhydrouronic acid content of pectin (88.8 ± 0.21%–90.82 ± 0.11%) represents the superior purity of pectin. The higher degree of esterification (> 50%) indicates the extracted pectin is a high ester pectin. The similarity of FT‐IR spectra at 800–1300 cm−1 with the “fingerprint zone” of carbohydrates indicates that extracted pectin is functional pectin. The results showed that ultrasound‐ and microwave‐assisted NADES are efficient systems for extracting pectin with a high degree of esterification from mango peels.

An eminent approach towards next generation solvents for sustainable packaging and stability of enzymes: a comprehensive study of ionic liquid and deep eutectic solvent mixtures.

Hybrid ionic fluids (HIFs) are newly emerging and fascinating sustainable solvent media, which are attracting a great deal of scientific interest in protecting the native structure of proteins. For a few decades, there has been a demand to consider ionic liquids (ILs) and deep eutectic solvents (DESs) as biocompatible solvent media for enzymes; however, in some cases, these solvent media also show limitations. Therefore, this work focuses on synthesising novel HIFs to intensify the properties of existing ILs and DESs by mixing them. Herein, HIFs have been synthesised by the amalgamation of a deep eutectic solvent (DES) and an ionic liquid (IL) with a common cation or anion. Later on, the stability and activity of hen's egg white lysozyme (Lyz) in the presence of biocompatible solvent media and HIFs were studied by various techniques such as UV-vis, steady-state fluorescence, circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) and dynamic light scattering (DLS) measurements. This work emphasises the effect of a DES (synthesised using 1 : 2 choline chloride and malonic acid) [Maline], ILs (1-butyl-3-methylimidazolium chloride [BMIM]Cl or choline acetate [Chn][Ac]) and their corresponding HIFs on the structure and functionality of Lyz. Moreover, we also studied the secondary structure, thermal stability, enzymatic activity and thermodynamic profile of Lyz at pH = 7 in the presence of varying concentrations (0.1 to 0.5 M) of [BMIM]Cl and [Chn][Ac] ILs, Maline as a DES, and Maline [BMIM]Cl (HIF1) and Maline [Chn][Ac] (HIF2). Spectroscopic results elucidate that ILs affect the activity and structural stability of Lyz. In contrast, the stability and activity are inhibited by DES and are enhanced by HIFs at all the studied concentrations. Overall, the experimental results studied explicitly elucidate that the structure and stability of Lyz are maintained in the presence of HIF1 while these properties are intensified in HIF2. This study shows various applications in biocompatible green solvents, particularly in the stability and functionality of proteins, due to their unique combination where the properties counteract the negative effect of either DESs or ILs in HIFs.

Galactomannan crosslinking with a green plasticizer malonic acid and its biomedical applications

The galactomannan has been crosslinked with malonic acid at 55 °C in aqueous medium to introduce 1,3-propane dioate moieties. The prepared formulation has utility in sustained drug delivery exemplifying conversion of biomass to biomedical products.

What is better to enhance the solubility of hydrophobic compounds in aqueous solutions: eutectic solvents or ionic liquids?

The solubilities of three solutes in aqueous solutions of ionic liquids (choline glycolate and choline malonate) and the analogous eutectic solvents (choline chloride:glycolic acid and choline chloride:malonic acid) were studied.

A mesoionic carbene stabilized nickel(II) hydroxide complex: a facile precursor for C-H activation chemistry.

We report the synthesis of a new nickel(II) hydroxide complex 2 supported by a rigid, tridentate triazolylidene-carbazolid ligand. The complex can be accessed in high yields following a simple and stepwise extraction protocol using dichloromethane and aqueous ammonium chloride followed by aqeous sodium hydroxide solution. We found that complex 2 is highly basic, undergoing various deprotonation/desilylation reactions with E-H and C-H acidic and silylated compounds. In this context we synthesized a variety of novel, functionalized nickel(II) complexes with trimethylsilylolate (3), trityl sulfide (4), tosyl amide (5), azido (6), pyridine (7), acetylide (8, 9), fluoroarene (10 & 11) and enolate (12) ligands. We furthermore found that 2 reacts with malonic acid dimethyl ester in a knoevennagel-type condensation reaction, giving access to a new enolate ligand in complex 13, consisting of two malonic acid units. Furthermore, complex 2 reacts with acetonitrile to form the cyanido complex 14. The formation of complexes 13 and 14 is particularly interesting, as they underline the potential of complex 2 in both C-C bond formation and cleavage reactions.

Organocatalytic enantioselective decarboxylative protonation of α-alkyl-α-aryl malonate monoesters.

In contrast to the well-established enzymatic enantioselective decarboxylative protonation (EDP), the corresponding chemocatalytic reactions of acyclic malonic acid derivatives remain challenging. Herein, we developed a biomimetic EDP of α-alkyl-α-aryl malonate monoesters using a chiral 1,2-trans-diaminocyclohexane-based N-sulfonamide as an organocatalyst. The method demonstrates excellent chemical yields, good enantioselectivity, mild reaction conditions, and the generation of only CO2 as waste.

Synthesis of malonic acid esters

Synthesis of malonic acid esters

Nucleation of Methane Hydrate from Water and Aqueous Solutions of Malonic Acid in Glass Cells with Varying Surface Hydrophilicity

Nucleation of Methane Hydrate from Water and Aqueous Solutions of Malonic Acid in Glass Cells with Varying Surface Hydrophilicity

Malonic acid shapes bacterial community dynamics in compost to promote carbon sequestration and humic substance synthesis

The incorporation of malonic acid (MA) into compost as a regulator of the tricarboxylic acid (TCA) cycle has the potential to increase carbon sequestration. However, the influence of MA on the transformation of the microbial community during the composting process remains unclear. In this investigation, MA was introduced at different stages of chicken manure (CM) composting to characterize the bacterial community within the compost using high-throughput sequencing. We assess the extent of increased carbon sequestration by comparing the concentration of total organic carbon (TOC). At the same time, this study examines whether increased carbon sequestration contributes to humus formation, which was elucidated by evaluating the content and composition of humus. Our results show that the addition of MA significantly improved carbon sequestration within the compost, reducing the carbon loss rate (C loss (%)) from 64.70% to 52.94%, while increasing HS content and stability. High throughput sequencing and Random Forest (RF) analysis show that the introduction of MA leads to a reduction in the diversity of the bacterial communities, but enhanced the ability of bacterial communities to synthesize humus. Furthermore, the addition of MA favors the proliferation of Firmicutes. Also, the hub of operational taxonomic units (OTUs) within the community co-occurrence network shifts from Proteobacteria to Firmicutes. Remarkably, our study finds a significant decrease in negative correlations between bacteria, potentially mitigating substrate consumption due to negative interactions such as competition. This phenomenon contributes to the improved retention of TOC in the compost. This research provides new insights into the mechanisms by which MA regulates bacterial communities in compost, and provides a valuable theoretical basis for the adoption of this innovative composting strategy.

Electrochemistry of copper post-CMP cleaning examined in combination with brush-scrubbing in a malonic acid solution

Post-CMP cleaning (PCMPC) is used in the fabrication of integrated circuits to remove unwanted residues of chemical mechanical planarization (CMP) from wafer surfaces. PCMPC combines (electro)chemical surface reactions in a cleaning solution with mechanical scrubbing by a brush. Using tribo-electrochemical protocols, the present work simultaneously probes the (electro)chemical and mechanical functions of PCMPC and determines the corresponding cleaning efficiency. Employing malonic acid as a cost effective, environmentally compatible cleaning solution for copper, it is demonstrated how this electroanalytical approach can facilitate the tasks of developing and evaluating effective PCMPC solutions. The results indicate that malonic acid in a pH neutral environment removes Cu-oxides and their co-adsorbed organic residues of CMP. A detailed electrochemical procedure is illustrated for quantifying the residue removal efficiency of PCMPC, and the role of brush scrubbing in the overall cleaning process is identified.

Optimization of Synergistic Leaching of Valuable Metals from Spent Lithium-Ion Batteries by the Sulfuric Acid-Malonic Acid System Using Response Surface Methodology

A new environmentally friendly and economical recycling process for extracting metals from spent lithium-ion batteries (LIBs) using sulfuric acid and malonic acid as leaching agents is proposed. By applying Box-Behnken design (BBD) and response surface methodology (RSM) optimization techniques, the global optimal solution of the maximum leaching rate of metals in spent LIBs is realized. The results show that under the optimal conditions of 0.93 M H2SO4, 0.85 M malonic acid, liquid/solid ratio of 61 g·L–1, the temperature of 70 °C and 5 vol% of 30% H2O2, 99.79% Li, 99.46% Ni, 97.24% Co and 96.88% Mn are recovered within 81 min. The error between the theoretical value and the actual value of the metal leaching rate predicted by the regression model is less than 1.0%. Additionally, the study of leaching kinetics reveals that the leaching process of Li, Ni, Co, and Mn in spent cathode materials was affected by the synergistic effect of interfacial mass transfer and solid product layer diffusion. Economic analysis reveals that evaluation index should be fully considered when formulating recovery processes for different metals. This process can reduce the environmental risks of heavy metal disposal, and allow the reuse of metals recovered from spent LIBs.

A New Green Solvent: Synthesis and Characterization of Natural-Deep-Eutectic-Solvent (NADES) for Application on Aqueous-Two-Phase System (ATPS) for Extraction of Anthocyanin

Anthocyanins are said to possess antidiabetic, anticancer, anti-inflammatory, antimicrobial, and anti-obesity effects. There is lot of emphasis placed on the improvement of the methods for extracting anthocyanins; one of which being extraction via aqueous two-phase systems (ATPS). Aqueous two-phase system is a liquid-liquid extraction method that has many benefits like easy to scale up with high recovery yield. However, ATPS also has drawbacks as it utilizes organic solvents and low biodegradability ionic liquid. In this context, Natural Deep Eutectic Solvents (NADESs) which are inexpensive, eco-friendly can be employed in aqueous two-phase system. Thus, the purpose of this research is to explore the feasibility of NADES-ATPS in the extraction and purification of anthocyanins. This research will investigate the solubility of anthocyanins and characterize the NADESs in terms of density, viscosity, and polarity to screen out NADESs that are suitable to be used for the extraction of anthocyanins. To do this, 6 different types of NADES with different molar ration, such as 1:1,1:2 and 1:3 of hydrogen bond acceptor (HBA) to hydrogen bond donor (HBD) ratio, were prepared and screened. The NADES was prepared using choline chloride as HBA, and malonic acid, lactic acid, glycerol, ascorbic acid, urea, and citric acid as HBD. The solubility of 10% anthocyanin was found in a range of 0.60×10−2 g/g to 1.81×10−2g/g. The solubility of the anthocyanins in NADES was correlated to the viscosity and polarity of the NADES where it was seen that the solubility has a positive relationship with polarity. The solubility also showed a similar trend to the viscosity however up to critical point, upon which the solvent was too viscous and was unable to be utilized in room temperature. The research concludes that malonic acid-based NADES to be the most suitable to be utilized for the extraction of anthocyanin using ATPS.

Et2 Zn-Mediated Gem-Dicarboxylation of Cyclopropanols with CO2.

An unprecedented Et2 Zn-mediated gem-dicarboxylation of C─C/C─H single bond of cyclopropanols with CO2 is disclosed, which provides a straightforward and efficient methodology for the synthesis of a variety of structurally diverse and useful malonic acids in moderate to excellent yields. The protocol features mild reaction conditions, excellent functional group compatibility, broad substrate scope, and facile derivatization of the products. DFT calculations confirm that the transition-metal-free transformation proceeds through a novel ring-opening/α-functionalization/ring-closing/ring-opening/β-functionalization (ROFCOF) process, and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)plays dual important roles in the transformation.

Generalized Pitzer-Debye-Hückel (PDH) Framework for the Deep Eutectic Solvent Assisted Extraction of Europium (III), Americium (III), and Uranium (VI)

ABSTRACT This study focuses on modeling of deep eutectic solvents (DESs) assisted liquid-liquid-extraction of Am(III), U(VI), Eu(III). In the present work, DESs are having tri – n octyl phosphine oxide (TOPO) and choline chloride acetate as hydrogen bond acceptor and malonic acid, oxalic acid and glycolic acid as hydrogen bond donor. The UNIQUAC-extended-PDH* model is used in the extraction formulation incorporating weak long-range interactions and short-range interactions. Metaheuristic algorithm, such as genetic algorithm, is employed for the determination of thermodynamically consistent binary interaction parameters using a pool of 40 tielines across six systems. The estimation of efficiency evaluation and extraction quantification contributes to a deeper understanding of the behavior of deep eutectic solvents in the extraction of lanthanides and actinides.

Molecular dynamics investigation on structural and interfacial characteristics of aerosol particles containing mixed organic components

Microscopic morphology plays a significant role in the description of aerosol particle evolution, but the knowledge on particles containing mixed organic matters is insufficient. In this study, molecular simulation (MD) method is employed to investigate the morphologies of particles containing two or three of malonic acid (MA), adipic acid (AA) and eicosane (C20). The key point is the effects of organic species and water content on structural and interfacial characteristics of particles. Results show that all dry particles exhibit the approximate core-shell structure with the shell composed of organic with longer hydrocarbon chain. With water content increasing from 100 to 1000, MA + AA + H2O particles present the core-shell structure with decreasing MA in the core, while particles containing C20 successively exhibit the core-shell structure and the ball-cap structure with three layers. These structural differences are caused by the surface propensity of organics, which is positively correlated with both the length of hydrocarbon chain and the water content. At the particle surface, hydrophobic groups of organic molecules direct towards the gas phase. MA (AA) located between water droplet and C20 cluster orient their hydrophobic groups toward C20. Furthermore, ratios of hydrophilic and hydrophobic atoms (K) at the surface of all studied particles increases with increasing water content, and at each water content the order is K(MA + AA) > K(MA + AA + C20) > K(AA + C20) > K(MA + C20). These findings provide microscopic information support for the development of theoretical model for the particle formation and growth.

The proceeded ammonia release from ammonium nitrate owing to sodium malonate addition: Dependence of RH, acidity and surfactant

The gas-particle partition of ammonia has strong effect on size, composition and hygroscopic property of atmospheric aerosols. However, how chemical reaction drives ammonia evaporation from particle is not well known. In this work, ammonium depletion is used to characterize the ammonia liberation from aqueous ammonium nitrate and sodium malonate/ammonium nitrate aerosols. The addition of sodium malonate promotes more ammonia liberation owing to inter-ingredients reaction. As the relative humidity (RH) decreases, ammonia release is enhanced. Moreover, NH3 evaporation is also impacted by aerosol acidity. At pH 1.93, malonate is directly converted into hydrogen malonate and malonic acid via protonation. Under the neutral/alkaline condition, higher pH is beneficial for component reactions. When cetyltrimethylammonium bromide is added into mixed aerosols, NH3 evaporation becomes slow. These results can provide a new perspective on the evolution mechanism of NH3–NH4+ buffer pairs for multicomponent aerosols.

Influence of malonik acid monoamides on the thermal-oxidating stability of dieseln fuel

To improve environmental standards from diesel fuels (DF), it is necessary to remove sulfur and nitrogen-containing heterocyclic compounds, which leads to a decrease in oxidative stability, since sulfur and nitrogen compounds are natural antioxidants and help to inhibit the oxidation process of diesel fuel. This article discusses the effective and promising antioxidants synthesized by us for hydrotreated diesel fuel. For this purpose, monoamides of malonic acid (MA) were synthesized; malonic acid and aliphatic amines (from butyl to nonylamine) of various structures were taken as starting compounds. Their structures were studied by IR spectroscopy. Their physicochemical properties have also been studied. With the addition of 0.004 % of the synthesized malonic acid monoamides to hydrotreated diesel fuel, compositions were prepared that were oxidized at 120 oC for 4 hours on an LSART apparatus. It has been established that, compared with the hydrotreated diesel fuel itself, monoamides of MA reduce precipitation by 2–45 times, and compared with the known ionol, MA monoamides have better performance, for example, with the addition of MA monobutylamide, precipitation decreases from 4.5 mg/100 ml to 0.5 mg/100 ml, and monoisobutylamide reduces to 0.1 mg/100 ml. Thus, monoamides of MA can be proposed as antioxidants for hydrotreated diesel fuel due to their high antioxidant properties.

Therapeutic effect of total flavonoids of Sargentodoxa cuneata on ulcerative colitis in mice by correcting gut dysbiosis

Sargentodoxa cuneata is a traditional Chinese herb commonly used for the treatment of ulcerative colitis (UC) in clinical practice. However, the effects of total flavonoids of Sargentodoxa cuneata (TFSc) remain unclear. In this study, we explored the effects and mechanisms of action of TFSc in mice with dextran sulfate sodium-induced UC. The TFSc components were identified using liquid chromatography-tandem mass spectrometry. Mice with UC were orally administered TFSc to evaluate its effects on colon and liver damage. Changes in gut microbiota were analyzed using 16S rRNA gene sequencing. Moreover, the levels of short-chain fatty acids (SCFAs) and few organic acids in the intestinal contents were measured. Furthermore, the correlation amongst gut flora, SCFAs, and organic acids was studied. A total of 304 compounds were identified. TFSc alleviated the symptoms of UC in mice, inhibited weight loss, reduced the disease activity index, and improved colon shortening along with cardiac and hepatic indices. Furthermore, TFSc mitigated pathological changes in the colon and liver, and reduced the TNF-α levels in colon tissues of mice with UC. TFSc also modulated intestinal flora disorders, increased the levels of four SCFAs (isocaproic acid, 3-hydroxyisovaleric acid, isobutyric acid, and ethylmethylacetic acid), and decreased the levels of two organic acids (malonic acid and succinic acid). The differential regulation of SCFAs and organic acids by TFSc was strongly associated with specific gut flora. TFSc showed potential for improving colon and liver injury in mice with UC by regulating the intestinal flora and associated metabolites (SCFAs and organic acids). These findings provide new evidence for developing TFSc as a drug for treating UC and UC-related liver injuries.

Reaction of chloroethynylphosphonates with 1,3-diethyl 2-(acylamino)propanedioates

Reaction of 2-(acylamino)malonic acids esters with chloroethynylphosphonates yielded 2-substituted (5 E / Z )-5-(dialkoxyphosphoryl)methylidene-2-oxazoline-4,4-dicarboxylates, isomers of which could be separated. Following reaction of hydrolysis and decarboxylation affords 2-substituted 5-(dialkoxyphosphoryl)methyl-1,3-oxazole-4-carboxylates.