Tartaric Acid Research Articles

Essential amino acid residues and catalytic mechanism of trans-epoxysuccinate hydrolase for production of meso-tartaric acid.

This study aimed to discuss the essential amino acid residues and catalytic mechanism of trans-epoxysuccinate hydrolase from Pseudomonas koreensis for the production of meso-tartaric acid. The optimum conditions of the enzyme were 45°C and pH 9.0, respectively. It was strongly inhibited by Zn2+, Mn2+ and SDS. Michaelis-Menten enzyme kinetics analysis gave a Km value of 3.50mM and a kcat of 99.75s-1, with an exceptional EE value exceeding 99.9%. Multiple sequence alignment and homology modeling revealed that the enzyme belonged to MhpC superfamily and possessed a typical α/β hydrolase folding structure. Site-directed mutagenesis indicated H34, D104, R105, R108, D128, Y147, H149, W150, Y211, and H272 were important catalytic residues. The 18O-labeling study suggested the enzyme acted via two-step catalytic mechanism. The structure and catalytic mechanism of trans-epoxysuccinate hydrolase were first reported. Ten residues were critical for its catalysis and a two-step mechanism by an Asp-His-Asp catalytic triad was proposed.

Antimicrobial effect of plasma-activated water combined with tartaric acid against Staphylococcus aureus and its application on fresh-cut asparagus lettuce

Plasma-activated water (PAW) is increasingly recognized for its role in mitigating microbial contamination in fresh-cut produce, but its disinfection effectiveness can be limited under certain conditions. Notably, dissolving organic acids in PAW is an effective way to boost its antimicrobial properties through a synergistic effect. This study examined the enhanced antimicrobial efficacy of PAW when combined with tartaric acid against Staphylococcus aureus and its application on fresh-cut asparagus lettuce. Results demonstrated that PAW combined with tartaric acid showed stronger antimicrobial efficacy than PAW alone (p < 0.05). The addition of tartaric acid to PAW increased the oxidation-reduction potential and lowered the pH, contributing to its superior antimicrobial performance against S. aureus. The underlying antimicrobial mechanisms included the inactivation of Ca2+-Mg2+-ATPase and Na+-K+-ATPase accompanied by damage to bacterial cell membrane, enhanced oxidative damage due to the influx of extracellular reactive oxygen species such as H2O2, the disrupted energy metabolic activities, and the mitigated bacterial defense system constructed by antioxidant enzymes, such as superoxide dismutase and catalase. Furthermore, the synergistic treatment improved the quality of fresh-cut asparagus lettuce by retarding browning, curbing microbial spoilage, and lessening weight loss. The preservation of color was largely due to the decreased activities of polyphenol oxidase and peroxidase, along with controlled chlorophyll degradation. These findings suggest that PAW enhanced with tartaric acid could be a promising, cost-effective disinfection strategy for fresh-cut asparagus lettuce.

A comprehensive evaluation of different responses of supplementary light qualities on physiological and biochemical mechanisms of ‘Kyoho’ grape

Grape is an economically important fruit crop worldwide, for which light qualities play a diverse role in vineyard growth and development. However, the regulatory mechanisms between different light qualities and the quality of plant growth at the morphophysiological and pomological levels remain unknown. Therefore, in the current study, we studied plant physiological, biochemical and genetical analysis to investigate the response of all seven light qualities, including red (R), blue (B), white (W), 1-red, 1 blue (1R1B), 2-red, 1-blue (2R1B), 1-red, 2-blue (1R2B), and natural (N, was used as control group) to evaluate ‘Kyoho'grape (Vitis labrusca L. × V. vinifera) morphophysiological, pomological traits at light responsive transcriptional pathway, which revealed the possible networking metabolism controlling fruit quality and quantity of grape plant. Our results showed that photosynthetic indicators such as leaf stomata, number of stomata, and longitudinal and transverse diameter of stomata improved under red and blue light qualities as compared to white light. Leaf gas exchange indicators showed that net photosynthetic rate, transpiration rate, intercellular CO2 concentration rate, total conductance to CO2, stomatal conductance, conductance to water vapor, maximal quantum yield of PS (II), actual photochemical quantum efficiency, electron transfer chain, and non-photochemical quantum efficiency improve under blue and red light. Photosynthetic pigments showed that chlorophyll a and b, carotenoid, and total pigment contents improved under blue and red light. Nutrient elements showed that potassium, phosphorous, magnesium, calcium, iron, and zinc contents improved under blue and red light. Morphological and organic acid indicators such as the appearance of fruit shape, firmness, and titratable acidity improved under blue and light. However, there was a notable increment in the total soluble sugar under blue and red light as compared to natural light. The composition of sugar including (sucrose, fructose, glucose) and organic acids (tartaric acid, citric acid, and malic acid) improved under blue and red light (fruits) and showed notable reductions for tartaric acid under blue and red light (leaves) as compared to natural light. Aromatic compounds showed that esters, aldehydes, acetaldehyde, 2-hexenal, ethyl acetate, n-propyl acetate, butanoic acid, ethyl ester, 1-hexanol, 2-ethyl, 2-propanone, and 1‑hydroxyl, improved under blue and red light. Further, changes in enhanced expression of light-responsive genes including VvCRYI, VvCRY2, VvPHYA, VvPHYB, VvCOP1, VvHY5, VvHYH, and VvPIF4 upregulated under blue and red light, while VvPIF3.1 down-regulated as compared to natural light. Also, chlorophyll synthesis-related genes including VvSGR, VvPAO, and VvCHLH upregulated under blue and red light, while VvNYC1, VvPPH, and VvPOR showed noticeable changes under blue and red light as compared to natural light. Interestingly, most of the relative genes were highly expressed in fruits as compared to leaves. Finally, we have established correlation and principal component analysis for indicators in grapes. Current findings provide novel mechanisms by which different responses of supplementary light control the plant fruit quality of grapes.

A prototype system for the removal of 137Cs from liquid radioactive waste using reverse osmosis membrane.

Cesium removal from aqueous solutions of radioactive waste streams is a challenge in the field of radioactive waste management; this is due to the small atomic radii of Cs+ metal ions and their high migration ability. So, the development of a withstand system for the removal of Cs+ is crucial. In the current study, the removal of radioactive cesium from aqueous solutions using an RO-TLC membrane was studied. Two modifications were conducted; the first is to enlarge the cesium metal ion radii by interacting with mono- and dibasic acids, namely, stearic acid, tartaric acid, citric acid, and EDTA, and the second is the modification of the RO membrane pore size via reaction with the same acids. The modification was confirmed using SEM, FTIR, and EDX analysis techniques. The Cs+ and K+ rejection capacities and water permeability across the membrane at 1.5 bars were evaluated. Along with using the above-mentioned acids, the Cs+ metal ion retention index (RCs) was also obtained. It was found that employing EDTA as a chelating agent in an amount of 1.5g/L in conjunction with the variation of feed content since it provided the highest value of RCs ~ 98% when used. Moreover, the elution of Cs+ using water, EDTA, ammonia, and HCl is also investigated. The optimal value of the eluent concentration was (0.25M) HCl. Finally, Langmuir and Freundlich isotherm models were applied for a better understanding of the sorption process. The results of the present work more closely match the Langmuir isotherm model to determine the dominance of the chemical sorption mechanism.

Study on the leaching of lithium from lithium-poor clay-type ore using tartaric acid by calcination and water leaching

This study focuses on the ore characteristics and occurrence status of lithium in lithium-poor clay-type ores by employing activation pretreatment by calcination followed by leaching with tartaric acid. This study investigates the influence of factors such as calcination temperature, calcination time, and leaching temperature on the leaching yield of Li. The findings show the optimal leaching conditions for Li extraction as follows: calcination temperature, 600 °C; calcination time, 5 min; leaching temperature, 100 °C; ore-tartaric acid mass ratio, 5:7; leaching time, 5 h; and ore-water ratio, 1:3 (g/mL), resulting in a leaching yield of Li of 85.0%. According to the results of the three-cycle leaching experiments, the Li concentration in the leach liquor increased from 40.2 mg/L to 125 mg/L, indicating efficient utilization of tartaric acid and successful Li enrichment. Moreover, the XRD, SEM, TG-DSC, and FTIR analyses of the samples reveal that tartaric acid dissociates into C4H5O6− and C4H4O62−, which then form complexes with ions such as Li+, Al3+, Ca2+, and Fe3+ that are dissolved during the ore leaching process. With an increase in leaching time, complexes involving Al, Ca, Fe, and tartaric acid radicals result in precipitation, leading to a reduction in the content of these ions in the leach liquor. This increases the selectivity of Li extraction, which is beneficial for the subsequent separation and extraction of Li.

Integrating low salinity water, surfactant solution, and functionalized magnetite nanoparticles with natural acidic groups for enhanced oil recovery: Interfacial tension study

In recent years, nanoparticles (NPs) have become a popular choice for improving oil recovery through enhanced oil recovery (EOR) methods. NPs can enhance oil recovery by reducing interfacial tension (IFT), altering wettability, and decreasing the mobility ratio. In this study, magnetic NPs with acidic groups (tartaric acid and malic acid), which are natural acids found in fruits such as grapes and apples, were synthesized and functionalized to reduce the IFT between oil and water. Various characterizations tests, including zeta potential (ZP), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray analysis (EDAX), were used to determine the properties of NPs. Afterwards, the IFT behaviour of crude oil and aqueous solutions, containing surfactant sodium dodecyl sulfate (SDS), two types of salts namely sodium chloride (NaCl) and sodium sulfate (Na2SO4), and functionalized magnetite NPs with tartaric acid and malic acid were investigated. Two crude oils were used in this study: light (A) and heavy (B). The results showed that increasing salt concentration decreases the IFT for crude oils down to an optimum point (20000 ppm for both salts), after which the IFT increases with increasing salt concentration. The presence of functionalized Fe3O4@Tartaric acid NPs (300 ppm) in the aqueous solutions containing salts at their optimum concentration (20000 ppm) and SDS (300 ppm) can decrease the IFT more significantly than that of Fe3O4 and Fe3O4@Malic acid for both crude oils. This is due to higher stability and higher ZP of functionalized Fe3O4@Tartaric acid NPs compared to Fe3O4@Malic. The IFT for oil A decreases from 20.8 mN/m to 2.87 mN/m for light crude oil and from 32.96 mN/m to 1.91 mN/m for heavy crude oil. The IFT for heavy crude oil was more reduced than that of light crude oil, which was due to the presence of asphaltene, resin, and other surface-active agents in heavy crude oil, which can act as a natural surfactant in oil and help reducing the IFT.

Fully bio-sourced catalyst-free covalent adaptable networks from epoxidized soybean oil and L-tartaric acid

Epoxidized vegetable oil (EVO)-based epoxy systems offer a promising avenue for replacing non-recyclable petroleum-based thermoset elastomers. Looking towards future prospects, they also hold potential to evolve into sustainable covalent adaptable networks (CANs). Typically, transesterification-based CANs require catalysts to achieve crosslinked structures that are reprocessable at relatively high temperatures (T ≥ 150 °C). In this study, epoxidized soybean oil (ESBO) was cross-linked with a eutectic hardener composed of L-tartaric acid (TAR) and ethyl lactate (in an aqueous solution), resulting in the development of a fully bio-based 3D covalent network capable of reprocessing without the need for an exogenous catalyst. In addition, it was demonstrated that the peculiar structure of L-tartaric acid, with –OH groups linked to its backbone, plays a prominent role in the reactivity of the system. These free hydroxyl functions facilitate both the ring-opening of epoxides and transesterification reactions, thus enhancing both curing and covalent exchange kinetics.

Terahertz SWNT-based fluidic chip for sensing enantioselectivity

Enantioselectivity sensing is crucial in biological systems due to the impact of the selective behaviors of chiral compounds on their targets. Conventional approaches for detecting enantioselectivity are restricted by the presence of high phonon energy, complex device manufacturing processes, low sensitivity, and the need for large sample sizes. Here, we propose a single-walled carbon nanotube (SWNT)-based fluidic chip that uses terahertz (THz) optical rotatory dispersion (ORD) spectroscopy to detect tartaric acids with high selectivity in very small amounts of liquid. The chip is composed of tailored U-shaped metasurfaces that show significant amplification of the near-field around the typical peaks of tartaric acids in the ORD spectrum. Additionally, it includes subwavelength gratings made of SWNTs, allowing for accurate detection of polarization angles. The limit of detection (LOD) for D-tartaric acid and L-tartaric acid are 17.9 mg/L and 11.0 mg/L, respectively. The sensitivities are superior to those of UV ORD or CD spectrometers. Furthermore, the presence of tartaric acid in wine is effectively identified, with a LOD of 25.60 mg/L. This technological development provides a significant improvement in chiral analysis by allowing for quick, highly sensitive, and precise detection of enantiomers.

Nanolevel of detection of ascorbic acid using horse-radish peroxidase inhibition assay

Ascorbic acid plays a significant role in regulation of various bodily functions with high concentrations in immune cells and being involved in connective tissue maintenance. Commonly it is detected through various colorimetric methods. In this study, we propose a one-step simple method based on the inhibitory activity of ascorbic acid on horseradish peroxidase and hydrogen peroxide. The detection is observed by colorimetric changes to TMB (3,3′,5,5′ tetramethylbenzidine). The enzyme inhibition unit was optimized with a high level of linearity (r2 = 0.9999) and the level of detection and level of quantification were found to be 1.35 nM and 4.08 nM, respectively with higher sensitive compared to the HPLC method (11 μM). Both intra and inter-assays showed high correlations at different AA concentrations. (r2 > 0.9999). Similar results were also observed for vitamin C tablets, ascorbate salts, fruits, and market products (r2 = 0.999). There was negligible effect of interference by citric acid, lactic acid, tartaric acids, and glucose with high recoveries (>98%) at 1 mg/mL to 0.0078 mg/mL concentration ranges. The recovery error (RE%) was found to be less than 10%. Our detection method is distinguished by its simplicity, nano-level of detection, reproducibility, and potential application and adaptability as a point-of-use test.

Depletion of Free Chlorine and Generation of Trichloromethane in the Presence of pH Control Agents in Chlorinated Water at pH 6.5

Chlorine is commonly used by the fresh produce industry to sanitize water and minimize pathogen cross-contamination during handling. The pH of chlorinated water is often reduced to values of pH 6–7, most commonly with citric acid to stabilize the active antimicrobial, hypochlorous acid (a form of free chlorine). Previous studies have demonstrated that citric acid reacts with chlorine to form trichloromethane, a major chlorine by−product in water and a potential human carcinogen. However, it is unclear if other pH control agents could be used in the place of citric acid to minimize the formation of trichloromethane. The objective of the present study was to determine the reactivity of organic and inorganic pH control agents, with chlorine, to generate trichloromethane. Free chlorine (∼100 mg/L) was mixed with 10 mM of each of twelve organic acids and two inorganic pH control agents (i.e., sodium acid sulfate and phosphoric acid) to effect a pH level of 6.5. Free chlorine and trichloromethane levels were measured over 3 h at 3 and 22°C. Results demonstrated that ascorbic acid, dehydroascorbic acid, citric acid, and malic acid rapidly depleted free chlorine concentrations at both 22°C and 3°C, while tartaric acid and lactic acid decreased chlorine concentrations more slowly. Other pH control agents did not significantly reduce free chlorine either at 22 or 3°C. Citric acid led to the generation of significantly higher concentrations of trichloromethane than did other acids. Chloroacetone was also found in chlorinated water in the presence of citric acid and ascorbic acid. Taking buffering capacity and pKa values into account, phosphoric acid and some organic acids may be used to replace citric acid as pH control agents in chlorinated water for washing fresh produce, to stabilize free chlorine level and reduce the generation of trichloromethane.

Impact of exogenous melatonin foliar application on physiology and fruit quality of wine grapes (Vitis vinifera) under salt stress.

Soil salinisation is an important abiotic stress faced in grape cultivating, leading to weakened plant vigour and reduced fruit quality. Melatonin as a novel hormone has shown positive exogenous application value. Therefore, this study used wine grape (Vitis vinifera ) 'Pinot Noir' as a test material to investigate the changes of foliar spraying with different concentrations of melatonin on the physiology and fruit quality of wine grapes in a field under simulated salt stress (200mmolL-1 NaCl). The results showed that foliar spraying of melatonin significantly increased the intercellular CO2 concentration, maximum photochemical quantum yield of PSII, relative chlorophyll and ascorbic acid content of the leaves, as well as the single spike weight, 100-grain weight, transverse and longitudinal diameters, malic acid, α-amino nitrogen and ammonia content of fruits, and decreased the initial fluorescence value of leaves, ascorbate peroxidase activity, glutathione content, fruit transverse to longitudinal ratio and tartaric acid content of plants under salt stress. Results of the comprehensive evaluation of the affiliation function indicated that 100μmolL-1 melatonin treatment had the best effect on reducing salt stress in grapes. In summary, melatonin application could enhance the salt tolerance of grapes by improving the photosynthetic capacity of grape plants under salt stress and promoting fruit development and quality formation, and these results provide new insights into the involvement of melatonin in the improvement of salt tolerance in crop, as well as some theoretical basis for the development and industrialisation of stress-resistant cultivation techniques for wine grapes.

Tartaric Acid Cross-Linking Polyvinyl Alcohol as Degradable Separators for Rechargeable Lithium Ion Batteries.

The escalating focus on environmental concerns and the swift advancement of eco-friendly biodegradable batteries raises a pressing demand for enhanced material design in the battery field. The traditional polypropylene (PP) that is monopolistically utilized in the commercial LIBs is hard to recycle. In this work, we prepare a novel water degradable separators via the cross-linking of polyvinyl alcohol (PVA) and dibasic acid (tartaric acid, TA). Through the integration of non-solvent liquid-phase separation, we successfully produced a thermally stable PVA-TA membrane with tunable thickness and a high level of porosity. These specially engineered PVA-TA separators were implemented in LiFePO4 (LFP)|separator|Li cells, resulting in superior multiplicative performance and achieving a capacity of 88 mAh g-1 under 5 C. Additionally, the straightforward small molecule cross-linking technique significantly reduced the crystalline region of the polymer, thereby enhancing ionic conductivity. Notably, after cycling, the PVA-TA separators can be easily dissolved in 95°C hot water, enabling its reutilization for the production of new PVA-TA separators. Therefore, this work introduces a novel concept to design green and sustainable separators for recyclable lithium batteries.

Organic Acid‐Assisted Preparation of Hydroxyapatite‐supported Ni Catalysts for Arene Hydrogenation

Developing non‐noble metal catalysts that can efficiently and selectively hydrogenate arenes remains a significant challenge. In this study, we developed efficient Ni catalysts for the arene hydrogenation based on an organic acid‐regulated impregnation strategy. These easily accessible Ni catalysts demonstrated exceptional efficiency, selectivity, reusability, and good substrate compatibility. The influence of carbon chain lengths and side‐chain hydroxyl or amino groups on dicarboxylic acids used in the catalyst preparation was comprehensively investigated. Characterizations and kinetic studies demonstrated the influence of organic acids on the size of Ni nanoparticles, the proportion of metallic nickel, and the strength of surface acidity. These factors influenced the activation of arene and hydrogen, thereby affecting the hydrogenative activity. Notably, hydroxyapatite‐supported Ni catalyst, assisted by tartaric acid (Ni‐TA/HAP) with an appropriate tartaric acid‐to‐nickel ratio, resulted in relatively smaller Ni nanoparticles, an increased proportion of Ni0, and more acidic sites, thereby exhibiting the best hydrogenation performance.

Screening Organic Acid Contents of Tomato Landraces Collected From Aegean-Mediterranean Region of Anatolia

Tomato landraces can serve as valuable sources for breeding new cultivars aimed at enhancing fruit quality in terms of organic acids. Nineteen tomato landraces spread along the Mediterranean coasts of Anatolia were evaluated to determine their basic internal quality parameters and organic acid composition. The parameters assessed included fruit weight, diameter, length, pH, titrable acidity (TA %), soluble solid content (SSC%), SSC/TA ratio, and organic acids, such as oxalic (OA), tartaric (TarA), malic (MA), malonic (MalA), lactic (LA), acetic (AA), citric (CA), and ascorbic acids (AscA). Significant diversity was observed among the different landraces concerning these traits. Citric acid was found to be the most abundant organic acid within the landraces. Notably, the highest and lowest values for CA were recorded in Ege 8 (105.73 mg g-1) and TR62707 (31.10 mg g-1), respectively, making them promising sources for future breeding programs. Ascorbic acid (AscA) exhibited the lowest content among all the organic acids, ranging from 0.06 to 0.12 mg.g-1 (equivalent to 64-116 µg.g-1). Moreover, the landrace TR49646 displayed the highest malic acid content (8.23 mg g-1), making it a potential source for obtaining high malic acid content. Conversely, Ege 6 showed the lowest malic acid content (5.11 mg g-1). For health purposes, the landrace TR63233 was identified as having the lowest oxalic acid content. Multidimensional scale analysis further confirmed the potential candidates identified by the ANOVA and one-way ANOM tests. The results revealed a considerable diversity among the evaluated landraces, and the identified traits could be instrumental in selecting and breeding new cultivars with improved characteristics.

Screening and classification of rosehip (Rosa canina L.) genotypes based on horticultural characteristics

BackgroundDuring the pandemic, the interest in colorful wild small fruits increased due to their positive effects on health. Also it has become very important to offer species with high nutritional value as fresh or processed products for human consumption due to increasing world population and decreasing arable land. In this context, we characterized the horticultural characteristics of 11 rosehip genotypes grown from seeds.ResultsCitric acid was determined as the main organic acid in all the genotypes investigated. The mean values of the organic acids obtained from all the genotypes were found to be as follows: citric acid (7177 mg L–1), malic acid (3669 mg L–1), tartaric acid (1834 mg L–1), oxalic acid (1258 mg L–1), carboxylic acid (631.9 mg L–1), shikimic acid (157.8 mg L–1), ascorbic acid (155 mg L–1), and acetic acid (20.9 mg L–1). Ellagic acid was the dominant phenolic compound (90.1 mg L–1 – 96.2 mg L–1) in all genotypes. The average values obtained from all genotypes for total phenolics, total flavonoids, and antioxidant activity were 37 261 mg GAE L–1, 526.2 mg quercetin L–1, and 93.6%, respectively. These characteristics had the lowest coefficients of variation, which indicated that all genotypes were similar regarding high biochemical with antioxidant effect. In addition, fruit width, fruit length, and fruit weight varied between 13.0 and 17.3 mm, 20.7 and 25.5 mm, and 1.4 and 2.7 g, respectively.ConclusionsThe genotypes were categorized according to different purposes, such as suitability for wine production, making vinegar, etc. While the pomological characteristics were strongly positively correlated among themselves, they were generally found to be negatively correlated with the phytochemical characteristics. Categorizing genotypes according to different usage purposes can improve the agricultural and industrial application of rosehip and enhance their breeding efficacy.

Exploration of genetic variability in Garcinia [&lt;i&gt;Garcinia gummi-gutta&lt;/i&gt; L.(Robson)] germplasm based on growth, yield and quality traits

Eleven Garcinia germplasm along with local check of Pechiparai were evaluated and underwent principal component analysis to assess genetic divergence and variation patterns during 2019 to 2022. The first two principal components, contributing significant Eigen values, explained 71.20% of the total variability. The Acc. Gg 9 was the top performer, exhibiting favourable yield and growth traits with lower pest and disease incidence, high biochemical compounds viz., hydroxy citric acid and tartaric acid compared to local check. Cluster analysis revealed four major clusters, offering diversity for breeding programs. Correlation studies highlighted traits such as number of fruits per tree, rind thickness, and tartaric acid showing significant positive correlations with yield per tree. Selection based on identified key traits was deemed crucial for enhancing effectiveness. Additionally, DNA fingerprinting analysis indicated the potential use of RAPD markers (OPA03570) for differentiating Kudampuli cultivar PPI (K) 1 from the local check. Overall, the present investigation provides insights into optimizing Garcinia breeding programs, emphasizing trait-based selection and DNA fingerprinting for varietal differentiation.

Separation and determination of percentage level niobium in gadolinium zirconate using bifluoride fusion and spectrophotometry

A simple and reliable method for the determination of percentage level niobium (3.5-8 %) in highly refractive gadolinium zirconate (Gd2Zr2O7) doped with niobium, a burnable poison material of nuclear reactor has been proposed. A fusion procedure using ammonium bifluoride (ABF) with Gd2Zr2O7 was developed. Fusion conditions such as time, temperature and ABF to sample ratio were optimised for realizing quantitative recovery of Nb. The fused masses obtained under different conditions were characterized using SEM-EDX and XRD to comprehend the conversion of the refractive oxide form to soluble fluoro compounds and their identification. The real samples fused under optimized conditions were dissolved in 2 % tartaric acid solution and the same was used for quantifying Nb employing spectrophotometry using 5-bromo pyrogallol red as chromogenic agent. Precision of the measurements was better than 3 % (RSD) for Nb(V) at 0.5 ppm and the accuracy of the method is 99.8 %.

Distribution Characteristics of Low-Molecular-Weight Organic Acids in Reclaimed Soil Filled with Fly Ash: A Study

This study aims to assess the contents of different kinds of low-molecular-weight organic acids (LMWOAs) in reclaimed soil filled with fly ash in the Huainan mining area in China using high-performance liquid chromatography (HPLC). Using a mobile phase consisting of 0.1% phosphoric acid and acetonitrile in a volume ratio of 98:2, the detection was performed at a wavelength of 210 nm for 15 min. In addition, a cluster analysis was performed on the detected LMWOAs in the reclaimed soil. The correlations between the LMWOA and nutrient contents in the reclaimed soil were also analyzed. In total, eight and seven LMWOAs were detected in the reclaimed soil and filled fly ash, respectively. In contrast, no LMWOAs were detected in the fresh fly ash from a thermal power plant. The order of total LMWOA contents at different sampling points followed the order of farmland control soil &gt; 1# (Triticum aestivum) &gt; 4# (Phragmites australis) &gt; 5# (Vigna radiata) &gt; 2# (Sorghum bicolor) &gt; 3# (Tamarix ramosissima) &gt; fly ash-filled soil. The farmland control soil and fly ash-filled soil exhibited the highest and lowest LMWOA contents of 648.22 and 85.09 μg·g−1, respectively. The LMWOA contents in the reclaimed soil followed the order of oxalic acid &gt; tartaric acid &gt; malonic acid &gt; lactic acid &gt; acetic acid &gt; citric acid &gt; propionic acid &gt; succinic acid. Indeed, oxalic acids exhibited the highest total amount of 1445.79 μg·g−1 and succinic acids exhibited the lowest total amount of 6.50 μg·g−1. The LMWOA contents in the reclaimed soil decreased with increasing soil depth, showing statistically significant differences between the 0–10 and 10–40 cm soil layers (p &lt; 0.05). According to the obtained clustering results, the detected LMWOAs can be divided into two categories. The first category consisted of oxalic acid, while the second category included the remaining LMWOAs. The soil LMWOA contents of 4# (Phragmites australis) and 5# (Vigna radiata) were significantly different from those at the other sampling points. According to the Pearson correlation analysis results, the occurrence and characteristics of the soil LMWOAs can be controlled by regulating the pH values and available nutrient contents in the soil, thereby improving the eco-environmental conditions of the reclaimed rhizosphere.

Impacts of continuous cropping on the rhizospheric and endospheric microbial communities and root exudates of Astragalus mongholicus

Astragalus mongholicus is a medicinal plant that is known to decrease in quality in response to continuous cropping. However, the differences in the root-associated microbiome and root exudates in the rhizosphere soil that may lead to these decreases are barely under studies. We investigated the plant biomass production, root-associated microbiota, and root exudates of A. mongholicus grown in two different fields: virgin soil (Field I) and in a long-term continuous cropping field (Field II). Virgin soil is soil that has never been cultivated for A. mongholicus. Plant physiological measurements showed reduced fresh and dry weight of A. mongholicus under continuous cropping conditions (i.e. Field II). High-throughput sequencing of the fungal and bacterial communities revealed differences in fungal diversity between samples from the two fields, including enrichment of potentially pathogenic fungi in the roots of A. mongholicus grown in Field II. Metabolomic analysis yielded 20 compounds in A. mongholicus root exudates that differed in relative abundance between rhizosphere samples from the two fields. Four of these metabolites (2-aminophenol, quinic acid, tartaric acid, and maleamate) inhibited the growth of A. mongholicus, the soil-borne pathogen Fusarium oxysporum, or both. This comprehensive analysis enhances our understanding of the A. mongholicus microbiome, root exudates, and interactions between the two in response to continuous cropping. These results offer new information for future design of effective, economical approaches to achieving food security.

Effects of verjus acidification on muscat canelli grape juice and wines

Our study aimed to investigate the use of verjus (green grape juice) as an acidifying agentfor improving the overall acid profile and balance of wine, lowering the pH and alcohol content and creating a sustainable winemaking practice that can be utilised in warm grape-growing regions, such as Texas, where pH levels range from 3.5 to over 4.0 in white juice and wine. Muscat Canelli wines were produced using two different treatments for pH and acidity balance. Verjus was produced by pressing under-ripe grapes resulting from crop thinning practices and added at two different rates of 2 % and 11 % to juice obtained from ripe grapes prior to fermentation. For all the wines produced, pH, titratable acidity (expressed as g/L Tartaric Acid), alcohol, glucose-fructose, l-malic acid, tartaric acid, potassium, polyphenols were analysed, and preference testing was performed via consumer sensory panels. Results obtained indicate that verjus can be used to balance pH and acidity as well as lower alcohol content. Consumer preference ranking indicated no significant differences between any of the treatments, while acidity rankings correctly distinguished the wines according to their acid levels. This work shows that the use of verjus as a pre-fermentation acidification agent could be a potential tool for winemaking to help mitigate the negative effects associated with climate change.