Chemical Papers最新文献

Snake wine and other venom-infused alcoholic beverages are sold across Asia, where many people believe in their health benefits despite occasional cases of poisoning. However, regulating these products poses a challenge for authorities, as existing toxin detection methods are costly and time-consuming. This study presents a simple and low-cost method for detecting and measuring phospholipase A2 enzymes (PLA2s), key toxic enzymes found in snake venom. PLA2s were extracted from monocled cobra (Naja kaouthia) venom and commercial snake wine using a three-phase partitioning (TPP) method. The extracted PLA2s were analyzed by high-performance liquid chromatography. Optimization revealed that trifluoroacetic acid was the most effective purification solvent and the TPP conditions involved 60% (w/v) ammonium sulfate with tertiary-butanol, followed by centrifugation at 600 g and separation in an Apollo C18 column with detection at 220 nm. The calibration curve was linear in the range of 50–500 µg mL⁻¹ (y = 11.836x – 112.48, R² = 0.9978). Recoveries and coefficient of variation ranged from 89.4 to 98.3 and 0.3 – 5.9%, respectively. The limit of detection was 5.276 µg mL⁻¹. This validated method enables rapid, accurate monitoring of PLA2s in snake venom-infused alcoholic products, supporting efforts to improve public safety and product regulation.

Andrographis paniculata has been traditionally used in Asian medicine for treating respiratory infections, including tuberculosis (TB), due to its known antimicrobial and immunomodulatory properties. In the present study, we evaluated the antitubercular potential of crude extracts, chromatographic fractions, and an isolated diterpenoid compound, 14-deoxy-11,12-didehydroandrographolide, against Mycobacterium tuberculosis H₃₇Rv and multidrug-resistant (MDR) strains. Sequential extraction of dried plant material was performed using hexane, chloroform, and methanol, followed by bioassay-guided fractionation and isolation of the active compound via column chromatography. Anti-TB activity was assessed using the microbroth dilution method in Middlebrook 7H9 medium, with minimum inhibitory concentrations (MICs) determined based on turbidity and the absence of bacterial cord formation. Among the crude extracts, the methanol extract showed significant activity with an MIC of 250 µg/mL. The isolated compound exhibited complete growth inhibition at 125 µg/mL against H₃₇Rv, and at 125 µg/mL, 62.5 µg/mL, and 125 µg/mL against MDR clinical isolates 1, 2, and 3, respectively. In comparison, rifampicin and isoniazid showed MICs of 1.0 µg/mL and 0.1 µg/mL against H₃₇Rv but demonstrated reduced efficacy (> 1.0 µg/mL and > 0.1 µg/mL) against the MDR strains. This is the first report to demonstrate the anti-tuberculosis efficacy of 14-deoxy-11,12-didehydroandrographolide. These findings support its potential as a promising therapeutic lead for the development of new drugs targeting drug-resistant TB.

In nuclear power plants (NPPs), contamination primarily results from the neutron activation of corrosion products, leading to the formation of radionuclides that are deposited on internal surfaces, particularly within the piping systems. These deposits increase radiation exposure risks for workers, especially during decommissioning. To mitigate this, chemical decontamination is employed to reduce surface radioactivity. However, many existing decontamination processes face limitations, including low oxide removal efficiency and significant corrosion of base metal surfaces. This study evaluates the potential of CHZ as an alternative decontamination agent, focusing on its magnetite dissolution efficiency and its corrosive impact on carbon steel SA106 Grade B, which simulates the feeder pipes of pressurized heavy water reactors. Batch experiments were conducted to assess both magnetite powder dissolution and metal corrosion using CHZ-based formulations. Results were compared with the Canadian Decontamination and Remediation (CANDEREM) process. CHZ-based reagents demonstrated superior dissolution performance, achieving up to 206.6 ppm of dissolved iron after 9 h, compared to 116.6 ppm for the CANDEREM formulation. Furthermore, the corrosion induced by CHZ on SA106 Gr B was significantly lower than that observed with CANDEREM, suggesting a less corrosive property. CHZ-based reagent performance is enhanced by creating a reducing environment which facilitates the Fe³⁺ to Fe²⁺ conversion. CHZ is presented as a safer, more effective alternative for decontamination in NPPs.

The integrated membrane process for clarification and concentration of sodium salt of vitamin C is projected as an emerging technology in operations where salts/ions recovery is the prime objective. This study presents a novel integrated microfiltration-reverse osmosis process. The study achieved a product recovery rate of 94.7% and an overall product retention of 91.40%. A significant contribution of cake layer and fouling resistance was observed indicating greater salt retention. The MF process effectively removed larger impurities, while the RO process concentrated the desired product. The average flux values for microfiltration and reverse osmosis unit were 14.13 and 7.19 L/m² h, respectively. The results indicate that the integrated MF-RO system can significantly enhance the recovery of sodium ascorbyl phosphate, demonstrating its potential for practical applications in industries focused on salts and ions recovery. Good restoration of water permeability of the membrane for both MF-RO was observed after cleaning treatment.

This study focuses on the synthesis routes of monoammonium phosphate (MAP), a fertilizer widely used in modern agriculture and known for its high phosphorus and nitrogen content. MAP is produced through the controlled mixing of ammonia and industrial phosphoric acid, culminating in an equimolar ratio in the granulator. This acid–base neutralization reaction can follow two distinct pathways based on the titration mode, which are forward and back titration. The primary objective of this research is to conduct detailed physicochemical studies of the MAP product in order to assess and understand the influence of each synthesis pathway on the physicochemical properties of the granules with a focus on dust emission. Various techniques have been used to characterize the slurry and granulated MAP, such as SEM, NMR, TGA, XRD, dust and hardness measurements, as well as other chemical analyses. XRD, FTIR, and NMR analyses confirmed that both the back titration and the forward titration allowed to synthesis MAP at the molecular level. However, these pathways showed two effects: the first, on the morphology, texture, hardness of the MAP particles and dust generation, and the second, on the crystallization form of the impurities (Al, Fe) NH₄H₂(PO₄)₂·0.5H₂O and (Al, Fe) NH₄HF₂PO₄, which affect the physical behavior of MAP particles.

This work is an in-depth study of the topological complexity of Lithium Manganese Arsenide (LiMnAs) through the application of chemical graph theory. By representing the molecular structure in graph form, a number of Zagreb-type topological indices were computed to quantify the connectivity and geometry of the extended LiMnAs lattice. Corresponding Shannon entropies were obtained from the indices for measuring the irregularity and information content in the molecular graph. A logarithmic regression model was utilized to determine the quantitative relationship between every index and its corresponding measure of entropy. The findings show strong logarithmic fits, confirming the application of topological indices as good descriptors of structural entropy. In addition, violin plots were utilized for the visualization of indices and measures of entropy, and the subtleties in structural behavior were highlighted. These results help in the topological characterization of LiMnAs and pave the way for its usage in materials physics and science.

Spices are important gastronomic ingredients utilized globally to increase the flavor of foods. This study aimed to compare the quality characteristics and effects of classic extraction (CE) and ultrasound-assisted extraction (UAE) on the bioactivity of 10 selected medicinal aromatic spices (mint, thyme, black pepper, cumin, clove, green cardamom, turmeric, ginger, cinnamon and sumac) frequently used in world cuisines. The analyses revealed that the spices were good sources of protein (4.71–19.68%) and ash (6.45–15.53%). The L*, a*, b*, H°, C*, browning index (BI), whiteness index (WI) and yellowness index (YI) values of the spice samples ranged from 24.70 to 71.36, −1.33 to 18.55, 1.76–59.22, 23.79–95.23, 4.37–62.06, 19.40–214.77, 24.55–63.09 and 10.06–137.89, respectively. Generally, the difference in the antioxidant capacity between the CE and UAE methods was statistically significant (P < 0.05). UAE treatment significantly decreased the extraction time of bioactive compounds from spices. The total phenolic content (TPC), total flavonoid content (TFC), DPPH·, CUPRAC and FRAP values of the spices ranged from 7.96 to 145.98 mg GAE/g, 7.85–271.36 mg QE/g, 1.57–172.94 mg TE/g, 9.57–744.27 mg TE/g and 1.50–423.53 mg TE/g, respectively. With both extraction methods, the highest antioxidant capacity was detected in clove, whereas the lowest was detected in green cardamom. Principal component analysis (PCA) indicated that cloves had the most distinct and strong antioxidant capacity, followed by cinnamon and sumac. In conclusion, we believe that this research contributes to both the importance of selected spices in nutrition and gastronomy and the role of the extraction technique in optimizing the health-promoting potential of spices for food and nutraceutical applications.

Graphical abstract

Near-infrared (NIR) boron dipyrromethene (BODIPY) dyes have gained attention among various fields due to their intense absorption and emission in the NIR region. In addition to intense absorption in the NIR region, having properties such as high singlet oxygen quantum yield (Φ_∆) and high molar extinction coefficient make them enable to use as photosensitizer in photodynamic therapy (PDT) and sono-photodynamic therapy (SPDT). In this study, two novel macrocyclic BODIPY derivatives including –OH and –NO₂ at para position of meso substituent of BODIPY cores have been synthesized and their molecular structures were determined by FT–IR, ¹H NMR and MS spectroscopic methods. Photochemical, sonochemical, and sono-photochemical properties of the synthesized compounds were examined. Φ_∆ values for sono-photochemical method were calculated as 0.86 for compound 1a and 0.98 for compound 2a. Despite the well-documented advantages of SPDT over standalone SDT or PDT in enhancing therapeutic efficacy, a comparative study assessing all three methods using BODIPY-based sensitizers has not yet been reported. This study fills that gap by demonstrating the ability of macrocyclic BODIPY derivative sensitizers including electron donor (–OH) and electron withdrawing (–NO₂) groups at para position of meso substituent to increase singlet oxygen generation using the SPDT method.

Cobalt sulfide (CoS) nanoparticles were synthesized via hydrothermal reaction route and evaluated for their electrochemical performances on carbon cloth substrate. The crystalline structure, morphology and chemical state of the prepared CoS nanoparticles are examined by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Structural characterization confirmed the formation of a hexagonal phase of CoS structure with a space group of P63/mmc. Electrochemical analysis revealed pseudocapacitive behavior, as evidenced by redox peaks observed in cyclic voltammetry (CV) curves. The CoS electrode achieved a maximum specific capacitance value ~ 382.3 F.g⁻¹ at scan rate of 5 mV.s⁻¹ and ~ 285.8 Fg⁻¹ at a current density of 2 Ag⁻¹. The electrode demonstrated excellent cycling stability retaining ~ 97% of its initial specific capacitance with coulombic efficiency ~ 96% after 5000 charge–discharge cycles. An asymmetric supercapacitor CoS//AC device was fabricated in a coin cell configuration and under 2 M KOH, the device delivered a specific capacity of ~ 560 mAh.g⁻¹ at 10 mV.s⁻¹ and ~ 430 mAh.g⁻¹ at 0.1 A.g⁻¹. The device attained maximum energy density of ~ 258 Wh.kg⁻¹ at 0.1 A.g⁻¹ and maximum power density of ~ 14.8 kW.kg⁻¹ at 1.2 A.g⁻¹, with capacity retention of ~ 86% after 2000 cycles. The results demonstrate a sustainable and eco-friendly approach to designing cobalt sulfide-based asymmetric devices for energy storage applications.

Graphical Abstract

Sustainable and eco-friendly based asymmetric supercapacitor of cobalt sulfide CoS nanoparticle fabricated on carbon cloth substrate for energy storage application.

In this research study, scale precipitation modeling in the presence of a scale inhibitor is carried out using the mixed-solvent electrolyte (MSE)-Soave–Redlich–Kwong (SRK) model. The Scalechem software of OLI systems was used for the modeling purposes. The state-of-the-art MSE–SRK model incorporated water, oil, gas, and inhibitors simultaneously for the accurate modeling of scale precipitation. The combination of PVT (SRK model) and aqueous phase model (MSE) strengthens the scale prediction capabilities of software and eliminates or reduces the limitations of previous models which work only on aqueous phase models. The MSE–SRK model is particularly designed for petroleum industry sector to yield accurate results by considering all phases and species present in the system under varying operating conditions. The model predicted scale precipitation in the absence and presence of scale inhibitors at various locations of production system. The inhibition efficiency of six scale inhibitors namely; C₂H₈O₇P₂ (HEDP), C₃H₁₂NO₉P₃ (NTMP/ATMP), C₄₀H₄₀O₄₀ (PMA/PMLA), C₇H₁₁O₉P (PBTC), C₆H₂₀N₂O₁₂P₄ (EDTMP/EDTMPA), and C₉H₂₈N₃O₁₅P₅ (DTPMP) at a dosage of 5000 mg/L was determined. The outcomes suggest that the scaling potential of Pyrrhotite was observed to be the largest followed by Calcite, Aragonite, and Mackinawite. The precipitation potential of different scale deposits was found to increase considerably from the reservoir toward the separator. Contour plots were generated to assess the precipitation potential of various scales over a wide range of temperature and pressure conditions. The results revealed that the scaling tendency of Pyrrhotite was found to be high while for Mackinawite, Gypsum, Anhydrite and Siderite scales was found to be low at all conditions of temperature and pressure. For Calcite scales, their scaling tendency was found to be high at all temperature and pressure values except at higher pressure and lower temperature, at which it became moderate. For inhibition modeling results, excellent performance was exhibited by C₃H₁₂NO₉P₃ (NTMP/ATMP). Average performance was observed for inhibitor C₇H₁₁O₉P (PBTC). The inhibitors C₄₀H₄₀O₄₀ (PMA/PMLA), C₂H₈O₇P₂ (HEDP), C₉H₂₈N₃O₁₅P₅ (DTPMP), and C₆H₂₀N₂O₁₂P₄ (EDTMP/EDTMPA) yielded poor efficiency. This research study demonstrated a novel and robust workflow, offered by Scalechem software, for the accurate prediction of carbonate and sulfide scale based on the MSE–SRK model,