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Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the fruit of Terminalia chebula, commonly known as chebulic myrobalan, is used as the precursor for carbon for its application in supercapacitors. The Terminalia chebula biomass-derived sponge-like porous carbon (TC-SPC) is synthesized using a facile and economical method of pyrolysis. TC-SPC thus obtained is subjected to XRD, FESEM, TEM, HRTEM, XPS, Raman spectroscopy, ATR-FTIR, and nitrogen adsorption–desorption analyses for their structural and chemical composition. The examination revealed that TC-SPC has a crystalline nature and a mesoporous and microporous structure accompanied by a disordered carbon framework that is doped with heteroatoms such as nitrogen and sulfur. Electrochemical studies are performed on TC-SPC using cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. TC-SPC contributed a maximum specific capacitance of 145 F g−1 obtained at 1 A g−1. The cyclic stability of TC-SPC is significant with 10,000 cycles, maintaining the capacitance retention value of 96%. The results demonstrated that by turning the fruit of Terminalia chebula into an opulent product, a supercapacitor, TC-SPC generated from biomass has proven to be a potential candidate for energy storage application. [ABSTRACT FROM AUTHOR]

Wound management is a critical aspect of healthcare, necessitating effective and innovative wound dressing materials. Many existing wound dressings lack effectiveness and exhibit limitations, including poor antimicrobial activity, toxicity, inadequate moisture regulation, and weak mechanical performance. The aim of this study is to develop a natural-based nanofibrous structure that possesses desirable characteristics for use as a wound dressing. The chemical analysis confirmed the successful creation of Zein (Ze) (25% w/v) /gelatin (Gel) (10% w/v) /chitosan (CS) (2% w/v) /Polyvinyl alcohol (PVA) (10% w/v) nanofibrous scaffolds loaded with vitamin E tocopheryl polyethylene glycol succinate (Vit E). The swelling percentages of nanofiber (NF), NF + Vit E, cross-linked nanofiber (CNF), and CNF + Vit E were 49%, 110%, 410%, and 676%, respectively; and the degradation rates of NF, NF + Vit E, CNF, and CNF + Vit E were 29.57 ± 5.06%, 33.78 ± 7.8%, 14.03 ± 7.52%, 43 ± 6.27%, respectively. The antibacterial properties demonstrated that CNF impregnated with antibiotics reduced Escherichia coli (E. coli) counts by approximately 27–28% and Staphylococcus aureus (S. aureus) counts by about 34–35% compared to negative control. In conclusion, cross-linked Ze/Gel/CS/PVA nanofibrous scaffolds loaded with Vit E have potential as suitable wound dressing materials because environmentally friendly materials contribute to sustainable wound care and controlled degradation ensures wound dressings breakdown harmlessly. [ABSTRACT FROM AUTHOR]

Terpenoids are known for their diverse structures and broad bioactivities with significant potential in pharmaceutical applications. However, natural products with low yields are usually ignored in traditional chemical analysis. Feature-based molecular networking (FBMN) was developed recently to cluster compounds with similar skeletons, which can highlight trace amounts of unknown compounds. Fusoxypene A is a sesterterpene synthesized by Fusarium oxysporum fusoxypene synthase (FoFS) with a unique 5/6/7/3/5 ring system. In this study, the FoFS-containing biosynthetic gene cluster was identified from F. oxysporum FO14005, and an efficient FBMN-based strategy was established to characterize four new sesterterpenoids, fusoxyordienoid A–D (1–4), based on a small-scale fermentation strategy. A cytochrome P450 monooxygenase, FusB, was found to be involved in the functionalization of fusoxypene A at C-17 and C-24 and responsible for the hydroxylation of fusoxyordienoid A at C-1 and C-8. This study highlights the potential of FBMN as a powerful tool for the discovery and characterization of natural compounds with low abundance. Key points: Combined small-scale fermentation and FBMN for rapid discovery of fusoxyordienoids Characterization of four new fusoxyordienoids with 5/6/7/3/5 ring system Biosynthetic pathway elucidation via tandem expression and substrate feeding [ABSTRACT FROM AUTHOR]

Charcoal kilns, old structures used for charcoal production in the forest, preserve a charcoal-enriched topsoil representing a suitable proxy for studying the long-term effect of biochar addition to soil. Two kiln platforms located at Gelbison and Vesole mountain sites in Southern Italy were selected due to their comparable climates but distinct parent rocks. We conducted standard soil chemical analyses and used next-generation sequencing to explore bacterial and fungal microbiome. Anthracology identified charcoal species, while scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) characterized charcoal particles. Reflectance Fourier transform infrared spectroscopy (DRIFTS) assessed biochar surface oxidation. Additionally, a bioassay with soybean, maize, and Tomato investigated the impact of kiln soil on plant performance. Our results showed that kiln soils did not exhibit higher pH, cation exchange capacity, or greater richness in cations. EDS and FTIR analyses showed that charcoal buried in forest soil for decades undergoes significant oxidation, with increased O/C ratio and the presence of oxygenated functional groups. Charcoal surfaces were selectively enriched with Ca2+ on limestone substrate sites but with Al and Si over sedimentary (flysch) substrate. While differences in the kiln soil and its surroundings were noticeable, they were not drastic in terms of microbial diversity and composition. Surprisingly, the bioassay indicated that the kiln microbiota had a more positive impact on plant growth compared to external forest soil. In conclusion, this study highlights the unique nature of kiln microsites and begins to unveil the enduring effects of charcoal accumulation on soil chemistry and microbiota in forest soil. Highlights: Kiln soils did not exhibit higher pH, cation exchange capacity, or greater richness in cations. Charcoal in forest kilns underwent significant oxidation with increased O/C ratio and presence of oxygenated functional groups. Charcoal surface showed different enrichment of Ca, Al, and Si influenced by the parent rock. Kiln microbiota exhibited a positive influence on plant growth, hinting at ecological benefits. [ABSTRACT FROM AUTHOR]

The applications of various clay minerals are related to their structural, physical, and chemical characteristics. These properties of the clay minerals dictate their utilization in the industries and beneficiation required before usage. The study aimed at establishing the potentiality of acid‐activated clay mineral from Hadar, Afar, Ethiopia. XRD, SEM, energy‐dispersive X‐ray fluorescence (EDXRF), and FT‐IR spectroscopies were employed to characterize the chemical compositions and interaction in the bentonite samples. The XRD results revealed that the native and activated bentonite clay contains similar minerals, such as montmorillonite (MMT) ([Ca, Na]0.33 [Al, Mg]2[Si4O10][OH]2.nH2O), quartz (SiO2), albite (NaAl2SiO6), zeolite (CaAl2O3.SiO2.nH2O), and aluminum silicate. Thus, attributes of the bentonite clay was composed of SiO2 and Al2O3 indicating that it is an aluminosilicate mineral, and the morphology of bentonite was supported by SEM. The chemical analysis by EDXRF revealed that the native bentonite (NB) consisting of 58.18 wt% (SiO2), 14.28 wt% (Al2O3), and Na2O > CaO are the major constituents of the clay with other oxides present in low amount. There was an increase in the SiO2 content in activated bentonites, and the Al2O3, Fe2O3, and MgO contents have decreased by 48.56%, 66.36%, and 84.42%, respectively. The FT‐IR spectra bands at 1627 cm−1 and 1027 cm−1 were attributed to Al–Mg–OH, Al–Al–OH, and Al–OH–O–Si stretching vibration, and the reduction of the content of the octahedral cations is accompanied by a decrease of both OH bending vibrations at 1627 and 3401 cm−1. The FT‐IR result is in clear agreement with the SEM, XRD, and EDXRF studies which indicate sequential degradation of the clay sheet upon acid treatment. Hence, rendering the activated bentonite clay of Hadar has accounted for their demand for different industrial applications such as its use as detoxifier, sealant, binder, fillers for paper, pharmaceutical products, absorbent, adsorbent, catalyst, and nanoclays. [ABSTRACT FROM AUTHOR]

Background: Analytical Quality by Design (AQbD) has emerged as a pivotal paradigm in the realm of analytical chemistry, revolutionizing the approach to method development and validation. This innovative strategy integrates principles of Quality by Design (QbD) into analytical procedures, aiming to ensure the quality and robustness of analytical methods. The traditional approach to method development often involves a trial-and-error process, where parameters are adjusted until satisfactory results are obtained. However, this approach can be time-consuming, resource-intensive, and may lack reproducibility. AQbD addresses these challenges by providing a systematic framework for method development that emphasizes understanding the relationship between critical process parameters (CPPs) and critical quality attributes (CQAs). Discussion: Analytical Quality by design (AQbD) presents an innovative approach to creating and validating analytical procedures, aimed at achieving quality measurements within the method operable design region (MODR). The QbD approach to analytical development is proactive, methodical, and risk-based significantly helps in acquiring an in-depth knowledge of how critical process parameters (CPPs) affect analytical performances, measured by critical quality attributes (CQAs). Experiment design (DoE) is an essential part of QbD, functioning to carry out the response surface analysis and screening process, and ultimately to enable the definition of the multidimensional region of the successful operating ranges of the CPPs, known as the design space (DS). The purpose of this article is to offer a thorough description of the QbD approach's method development process and its implementation in analytical procedure validation, to produce high-quality output, employing statistical analysis in conjunction with other designing tools. Conclusion: Analytical Quality by design (AQbD) offers a systematic and proactive approach to method development in analytical procedures. By focusing on method resilience and incorporating statistical analysis and experiment design (DoE), AQbD enables the production of high-quality outputs, while minimizing out of trend (OOT) and out of specification (OOS) results. This innovative strategy enhances the reliability and reproducibility of analytical methods, ultimately leading to improved outcomes across various industries. [ABSTRACT FROM AUTHOR]

Triazine‐based molecules have emerged as promising candidates for developing selective and sensitive chemosensors for metal ion detection. Their structural tunability facilitates the introduction of a variety of functional groups, improving their binding affinity and specificity toward a variety of metal ions. This review highlights various sensing mechanisms, including colorimetric and fluorometric methods, and provides insights into the performance of these sensors in terms of sensitivity, selectivity, and detection limits. The synthetic routes for synthesizing the chemosensors are mentioned in detail. Given their reliability and flexibility, triazine‐based sensors are poised to make significant contributions in the field of both sensor and analytical chemistry. [ABSTRACT FROM AUTHOR]

The development of environmentally friendly adsorbents has become increasingly important for treating waste generated by the growing global industry. In this study, new biosorbents were synthesized from an all-natural chitosan and watermelon pulp for the treatment of congo red textile dye from water. Biosorbents were prepared by lyophilizing chitosan-added watermelon pulp (AC-WPC). The prepared biosorbents were characterized by BET, SEM, Zeta Potential and FT-IR analysews. Accordingly, the BET surface area of AC-WPC was 120.92 m2/g. SEM analysis showed that the structures were porous and the results were consistent with the BET analysis. FT-IR analysis confirmed the chemical structures. The isoelectric points of the biosorbents were determined by zeta potential analysis. The AC-WPC biosorbent demonstrated 86% cell viability with cytotoxicity testing. For this reason, it was determined that the AC-WPC biosorbents produced does not cause any serious damage to the cell. Following this, adsorption study of congo red textile dye in water was carried out with these biosorbents. Langmuir and Freundlich isotherms were studied in adsorption experiments, and it was found that the Freundlich isotherms were compatible. Pseudo first and second kinetic models were also studied and found to be compatible with Pseudo Second Kinetic Model. The highest adsorption capacity was observed at 100 mg/l congo red concentration with 98.02% removal and 490.1 mg/g adsorption capacity using AC-WPC. It is thought that these results will potentially contribute to the literature on the removal of textile dyes or other pollutants using chitosan-added watermelon pulp. [ABSTRACT FROM AUTHOR]

Konjac glucomannan (KGM) and partially hydrolyzed polyacrylamide (HPAM) have good application prospects in the field of petroleum fracturing field, but few studies on the rheological properties of KGM and HPAM double polymer gel systems have been reported. Optimal conditions for the high temperature and shear resistant organozirconium crosslinked double polymer gel system for petroleum fracturing were explored through optimization experiments. The thickener contained a mass ratio of 2:1 of KGM to HPAM, while the organic zirconium crosslinking agent had controlled molar ratios of 1:4:3:3 of zirconium butoxide to ligand acetylacetone, triethanolamine, and glycerol. This work presents a systematic analysis of the chemical structure, microstructure, delayed crosslinking performance, temperature resistance, and shear resistance of the gel system. The study found that the crosslinking ratio of 100:2 resulted in a controllable delayed crosslinking time of the gel formed by the organic zirconium crosslinking agent and 4.0 g/L KGM/HPAM thickener within 5–25 min at room temperature. The viscosity remained above 81 mPa·s even after shearing for 100 min at 140°C and 170 s−1. These findings provide a useful reference for the application of organic zirconium crosslinked KGM/HPAM gel system in the petroleum fracturing field. [ABSTRACT FROM AUTHOR]

The results of studying the growth of para-quaterphenyl (4P) and its derivative—4,4'''-bis(trimethylsilyl)-para-quaterphenyl (TMS-4P-TMS)—crystals from solutions are presented. It has been established that TMS-4P-TMS crystals exhibit better growth characteristics as compared to 4Р. Parameters of the phase transitions of 4P and TMS-4P-TMS in closed crucibles were refined using differential scanning calorimetry. The crystal structure of TMS-4P-TMS in the triclinic space group P (Z = 2) has been decrypted for the first time using single-crystal X-ray diffraction and was studied in a wide temperature range. A crystallographic analysis of the studied compounds in crystals was performed using the Hirshfeld surface method, and modeling of intermolecular interactions was performed. [ABSTRACT FROM AUTHOR]

The potential adverse health effects of antiperspirant use are of interest to patients, primary care providers, dermatologists, and pathologists. In rare instances, antiperspirants containing aluminum–zirconium complexes have been associated with granulomatous dermatoses despite being deemed non‐sensitizing in experiments. In this case study, we present a detailed examination of an axillary granuloma in a 28‐year‐old female who had been using an aluminum–zirconium‐based antiperspirant for several years and presented with a left axillary nodule that was excised and analyzed using scanning electron microscopy with energy‐dispersive x‐ray analysis (SEM/EDXA). Histopathological examination revealed a foreign body‐type reaction with amphophilic granular material within giant cells that corresponded to collocated zirconium and aluminum on SEM/EDXA elemental maps. Our case adds to the limited reports of axillary granulomas related to aluminum–zirconium complexes. It illustrates the histopathological appearance and in situ distribution of the aluminum–zirconium complexes, supporting the formation of foreign body‐type granulomas. Additionally, our case study illustrates the potential role of these compounds in such reactions and aims to increase awareness among pathologists and clinicians. [ABSTRACT FROM AUTHOR]

Digital education plays a crucial role in promoting high-quality educational development, making the construction and application of digital resources particularly important. In the context of digital empowerment, this paper focuses on the construction of digital teaching resources for inorganic and analytical chemistry experimental course. Three aspects are discussed: the creation of a teaching video resource library, the development of a bilingual virtual simulation experiment, and the introduction of high-quality shared resources. These resources are then applied in teaching practice to enrich digital teaching materials, enhance online teaching platforms, and reform blended teaching models. Ultimately, this approach enhances the flexibility of experimental teaching, promotes diverse teaching methods, and improves the effectiveness of teaching. [ABSTRACT FROM AUTHOR]

Since the Ministry of Education launched a series of "101 Plan" for eight basic disciplines such as chemistry, Hunan University, as the leading unit of analytical chemistry courses in the Chemistry "101 Plan", has gathered 27 domestic "Basic Discipline Talent Training Plan 2.0 Base" universities in the field of chemistry to carry out the construction of courses and textbooks and promote the implementation of classroom improvement plans. This paper introduces in detail the core course knowledge system of analytical chemistry, the teaching contents and objectives of 11 modules and 48 core knowledge points, as well as the overall teaching objectives and construction progress of the course. [ABSTRACT FROM AUTHOR]

A U-shaped fixed bed reaction system was used to conduct pyrolysis experiments on 35 types of cigar tobaccos from eight different regions at home and abroad. The produced volatiles were analayzed in real-time by photoionization mass spectrometry (PI-MS). The principal component analysis (PCA) method was used to statistically analyze the obtained MS datas. The results showed that a total of 74 shared pyrolysis products were identified in the 35 types of cigar tobaccos, mainly hydrocarbons, phenols, ketones, alcohols, esters, and nitrogen-containing substances. There were significant differences in the composition of pyrolysis products between domestic and foreign cigar tobaccos. Especially, the domestic cigar coats had a much higher content of nicotine than the foreign cigar coats, whereas the relative content of fragrant components such as methylcyclopentenone, 2,3-dimethyl-2-cyclopentenone, and 2,5-dimethylcyclopentenone in the pyrolysis products of domestic cigar coats was lower than that of foreign cigar coats. The relative content of fragrant components such as 3-methylpyridine, 2,5-dimethylcyclopentenone, and (+)-limonene in the pyrolysis products of domestic cigar chips was lower than that of foreign cigar chips. In addition, the characteristic pyrolysis products of cigar tobaccos screened by PCA were consistent with the results of routine chemical composition analysis of cigar tobaccos, confirming the accuracy of the experimental analysis results. [ABSTRACT FROM AUTHOR]

In the study on volatile semiochemicals, we employed two headspace sampling methods: static and dynamic. Static headspace analysis utilized Solid Phase Microextraction (SPME), while dynamic headspace sampling involved techniques such as push–pull and closed loop stripping. Both methods are crucial for accurately detecting and characterizing the volatile profile of bloodsucking arthropods in situ or in vitro. This study examines differences in the chemical composition of volatiles extracted from the feces of two Chagasic bug species, Triatoma phyllosoma and Rhodnius prolixus, employing SPME and dynamic aeration techniques. Additionally, a standard synthetic blend of compounds (heptanal, octanal, nonanal, and decanal) mimicking a natural combination was utilized, with the evaporation of the blend monitored through gas chromatography-mass spectrometry (GC–MS) analysis. Volatiles were captured using seven distinct SPME fiber types and adsorbents: Tenax®, Super Q®, and activated charcoal. Comparative analysis was conducted between the amount and ratios of evaporated and those captured using dynamic and static headspace sampling methods. The advantages and disadvantages of each technique were thoroughly examined. Results indicate that activated charcoal, Tenax®, and the polydimethylsiloxane (PDMS)/divinylbenzene (DVB) fiber demonstrate superior accuracy in capturing short-chain aldehydes. Furthermore, the significance of employing multiple headspace sampling techniques within a chemical ecology framework is discussed. [ABSTRACT FROM AUTHOR]

Background and Aims Pit pairs and their filter-like partition, i.e. pit membranes, play important roles as water pathways, barriers and regulators in the water-conducting system of angiosperms. In Fraxinus species, the intervessel and vessel–parenchyma pit membranes in sapwood are normally encrusted during winter. Although these encrustations inevitably influence the performance of pits, their properties and functions remain unclear. This study aimed to reveal the morphological and chemical characteristics of encrustations in F. mandshurica in order to deepen understanding of the seasonal encrustation of pit membranes. Methods Seasonal and positional variations in the presence and morphology of encrustations were examined by field-emission scanning electron microscopy (FE-SEM). Cryo-FE-SEM for freeze-fixed greenwood samples was conducted to clarify whether encrustations were present in living trees. Chemical components were examined by histochemical staining using light and electron microscopy, immunofluorescence labelling and ultraviolet microspectroscopy. Key Results Encrustations began to deposit in autumn before leaf senescence and disappeared in spring before bud flushing. They infiltrated within the pit membranes, which suggested that they severely limit the permeation of pits. The encrustations differed in morphology among positions: they entirely filled the pit chambers in latewood, while they covered the pit membranes in earlywood. The encrustations were similarly observed in the samples that were freeze-fixed immediately after collection, indicating that they are present in living trees. The encrustations contained polysaccharides, including xyloglucan and homogalacturonan, and phenolic compounds, possibly including flavonoids and coumarins. These chemical components were also detected in droplets found in the latewood vessels with the encrustations, suggesting that the materials constituting encrustations were supplied through the vessel lumens. Conclusions Encrustations undoubtedly cover the pit membranes in living F. mandshurica trees in winter and their morphology and chemical composition indicate that they are impermeable, have positional differences in function and are characterized by elaborate deposition/removal processes. [ABSTRACT FROM AUTHOR]

The study examined building materials containing asbestos, which have been considered hazardous waste for several years. Samples were taken from various places in Poland. The chemical composition was examined using chemical analysis, the mineralogical phases were identified using X-ray diffraction, and the structure was identified using scanning electron microscopy, taking into account energy-dispersive spectroscopy. Thermal tests of the samples were performed using thermal analysis, thermogravimetric measurements and high-temperature microscopy. Additionally, changes that occurred in the microstructure were determined using mercury porosimetry and infrared spectroscopy. All the above research methods were used to characterise the properties of cement–asbestos materials, which were also subjected to isothermal thermal treatment at a temperature of 1100 °C for 4 h. The results proved that the material after thermal treatment undergoes significant structural changes. The thermal decomposition process of cement–asbestos involves dehydration, dehydroxylation and then recrystallisation to new stable crystalline phases but in the context of asbestos, we are dealing here with the so-called phenomenon of pseudomorphosis. Knowledge about the thermal properties of asbestos materials can provide us with data on how the material undergoes significant structural changes, thanks to which it will be possible to use neutralised cement–asbestos waste as possible safe materials. [ABSTRACT FROM AUTHOR]

In this article, we introduce a novel H-shaped plasmonic refractive index (RI) sensor coupled with a bus waveguide. The sensor is designed to interact with a straight metal-insulator-metal (MIM) waveguide configuration. To analyze the proposed structure, the finite element method (FEM) is employed, allowing for a comprehensive numerical investigation. The primary function of this sensor is to detect changes in RI by monitoring alterations in the resonant wavelength. The sensing mechanism involves the interaction of light with the plasmonic structure, and any variations in the RI of the surrounding medium induce changes in the resonant wavelength of the sensor. This phenomenon is crucial for applications such as biosensing and chemical analysis. To optimize the sensor's performance, the authors conducted a thorough process of geometric parameter optimization. Consequently, the recorded maximum sensitivity of the sensor, reported as 1960 nm/RIU for mode 2 and 1420 nm/RIU for mode 1, underscores its exceptional capability to discern minute quantities of molecules, showcasing a heightened sensitivity that sets it apart in molecular detection applications. Furthermore, we extend the applicability of their proposed sensor by numerically analyzing its performance in measuring the glucose content of blood. This highlights the versatility of the sensor, showcasing its potential for biomedical applications. [ABSTRACT FROM AUTHOR]

As a plant classified under the "medicine food homology" concept, garlic offers various health benefits and comes in many different varieties. In this study, the metabolite composition of different garlic varieties were analyzed using LC–MS/MS quadrupole‐Orbitrap mass spectrometry and ICP‐MS. A total of 30 chemical elements and 1256 metabolites were identified. Significant differences in chemical elements and metabolomics profiles were observed among the five garlic groups (VIP > 1.5). Compared to WG, PG contained 5 unique compounds, HG had 15 unique compounds, SCG had 18 unique compounds, and SBG had 26 unique compounds. Furthermore, the results showed that WG had smaller differences with PG and HG, but significant differences with SBG and SCG. KEGG analysis revealed metabolic pathways associated with the formation of differential metabolites. These findings uncover the differences and mechanisms in the composition of various garlic varieties, providing a theoretical foundation for distinguishing the nutritional components of different garlic types. [ABSTRACT FROM AUTHOR]

Chemical analysis showed that pH, b* values, myosin turbidity, carbonyl content, and surface hydrophobicity elevated in hooked, trawl‐net, and radar‐net hairtail (Trichiurus haumela, HH, TH, and RH) muscles with the prolonged cryopreservation time (‐18℃, 120 d). In contrast, L*, a* values, textural properties, and myosin solubility existed decreasing trends. Microstructural results showed that freezing resulted in disordered myofibrils, decreased collagen fibers, widened myofibrillar space, and increased fragmentation in hairtail muscles. Furthermore, volatile flavor analysis suggested that aldehydes, ketones, alcohols, and amines were the key factors for the overall flavor formation in hairtails during cold storage. Pearson correlation coefficient analysis revealed that the color, texture, and protein oxidation had close correlations with VOCs. Among the three different kinds of hairtail, fresh RH fillets exhibited an attractive aroma with high economic value, long‐term frozen TH muscle tissues were prone to deterioration in texture, microstructure, and flavor, and the HH samples presented stable quality characteristics and storage performance. [ABSTRACT FROM AUTHOR]

4-Acylpyrazolones are important ligands in analytical chemistry and technologies used for the separation and concentration of various metals. We have proposed a novel method for obtaining a material that consists of covalently immobilized functionalized ionic liquid on the surface of a mineral carrier featuring a coordination-active fragment of 4-acylpyrazolone. For its synthesis, we have introduced a strategy based on the quaternization of surface azolyl groups from 3-(1H-imidazol-1-yl)propyl silica with an alkylating reagent containing a 4-acylpyrazolone motif-4-(6-bromohexanoyl)-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one. This method of covalent immobilization preserves the 1,3-dioxo fragment, which ensures the effective binding of metal ions. The success of this functionalization has been confirmed by IR and 13C NMR spectroscopy data, as well as by thermogravimetric analysis. The overall functional capacity was found to be 0.3 mmol/g. The potential of the synthesized organomineral material to concentrate five rare earth elements (REEs) representing the cerium (Eu(III), Sm(III)) and yttrium groups (Gd(III), Dy(III), Er(III)) has been demonstrated. It was shown that during extraction from multicomponent systems, both under static and dynamic preconcentration conditions, there is a competitive influence of analytes, and their separation can be evaluated under dynamic conditions based on dynamic output curves and calculated distribution coefficients. It was shown that for systems where Kd > 1.8, quantitative separation can be performed in a dynamic mode of sorption under selected conditions. [ABSTRACT FROM AUTHOR]

Traditionally methods for assessing mutton quality rely on physical and chemical examination analyses that necessitate precise experimental environment conditions and specialized knowledge, often resulting in the compromise of the sample's structural integrity. To address these challenges, this study explores the application of near‐infrared spectroscopy (NIR) as a non‐destructive alternative for mutton quality evaluation, leveraging its operational simplicity, rapid analysis capabilities, and minimal requirement for technical expertise. Among various spectral data preprocessing techniques evaluated, multiple scattering correction (MSC) was found to significantly enhance model detection performance. Furthermore, principal component analysis (PCA) combined with the Mahalanobis Distance method was utilized for outlier identification. Finally, a mutton freshness detection model is constructed based on stacking ensemble learning, yielding an impressive accuracy rate of 0.976, outperforming other advanced approaches. In conclusion, our findings establish a robust theoretical framework for the rapid and non‐destructive assessment of meat freshness, contributing to advancements in meat quality detection. [ABSTRACT FROM AUTHOR]

The increasing demand for effective cosmetics has driven the development of innovative analytical techniques to ensure product quality. This work presents the development and validation of a zwitterionic hydrophilic interaction liquid chromatography method, coupled with ultraviolet detection, for the quantification of copper tripeptide in cosmetics. A novel protocol for sample preparation was developed using fabric phase sorptive extraction to extract the targeted analyte from the complex cosmetic cream matrix, followed by chromatographic separation on a ZIC®-pHILIC analytical column. A thorough investigation of the chromatographic behavior of the copper tripeptide on the HILIC column was performed during method development. The mobile phase consisted of 133 mM ammonium formate (pH 9, adjusted with ammonium hydroxide) and acetonitrile at a 40:60 (v/v) ratio, with a flow rate of 0.2 mL/min. A design of experiments (DOE) approach allowed precise adjustments to various factors influencing the extraction process, leading to the optimization of the fabric phase sorptive extraction protocol for copper tripeptide analysis. The method demonstrated excellent linearity over a concentration range of 0.002 to 0.005% w/w for copper tripeptide, with a correlation coefficient exceeding 0.998. The limits of detection and quantitation were 5.3 × 10−4% w/w and 2.0 × 10−3% w/w, respectively. The selectivity of the method was verified through successful separation of copper tripeptide from other cream components within 10 min, establishing its suitability for high-throughput quality control of cosmetic formulations. [ABSTRACT FROM AUTHOR]

The US Food and Drug Administration's (FDA) regulatory oversight over electronic cigarettes (e-cigs) includes access restriction for persons <21 years of age and flavor restrictions for "cartridge-based" products. Despite the restrictions, consumption by US youth perseveres. Studies on youth e-cig use are limited by the reliability and accuracy of self-reports. As an alternative to self-reports, the current study examined nicotine, cannabinoid, and unlabeled e-cigs and other vaping products confiscated from Virginia public schools to characterize trends among students. Findings highlight a shift from JUUL and pod-based products to single use disposable e-cigs following the FDA flavor restrictions on cartridge-based e-cigs. Chemical analysis of e-liquids by gas chromatography–mass spectrometry identified a wide variety of flavorants and an increase in the prevalence of synthetic coolants. Most confiscated products were nicotine salt formulations, but the prevalence of cannabinoid-based vaping products increased. The popularity of flavored disposable e-cigs highlights the need for further restrictions to reduce youth consumption. The increasing use of synthetic coolants instead of menthol may suggest that manufacturers are employing tactics to bypass regulations. Continued youth access to e-cigs and the abundance of cannabinoid-based products is problematic from health and safety perspectives. Continued research incorporating confiscated product analysis can be used to understand youth access to vaping products and evolutions in manufacturing practices. [ABSTRACT FROM AUTHOR]

Background/Objectives: Annona squamosa is used in folk medicine to treat pain and arthritis. Palmatine is an alkaloid isolated from several plants, including A. squamosa leaves. The aim of the present study was to investigate the analgesic, anti-arthritic, and anti-inflammatory potential of the methanolic extract of A. squamosa (EMAS) and palmatine. Methods: The chemical profile of EMAS was evaluated by ultra high-performance liquid chromatography with electrospray ionization coupled to mass spectrometry (UHPLC-ESI/MS). EMAS and palmatine were evaluated in carrageenan-induced pleurisy, zymosan-induced joint inflammation, formalin-induced nociception, and tumor necrosis factor (TNF)-induced mechanical hyperalgesia in experimental models in mice. A cytotoxicity test of EMAS and palmatine was performed using a methylthiazolidiphenyl-tetrazolium (MTT) bromide assay. Results: The analysis of the chemical profile of the extract showed the presence of palmatine, liriodenine, and anonaine. Oral administration of EMAS and palmatine significantly reduced leukocyte migration and oxide nitric production in the carrageenan-induced pleurisy model. EMAS and palmatine reduced mechanical hyperalgesia, leukocyte migration, and edema formation in the joint inflammation induced by zymosan. In the formalin test, palmatine was effective against the second-phase nociceptive response, mechanical hyperalgesia, and cold allodynia. In addition, palmatine reduced mechanical hyperalgesia induced by TNF. EMAS and palmatine did not demonstrate cytotoxicity. Conclusions: The present study showed that A. squamosa and palmatine are analgesic and anti-inflammatory agents, and that the anti-hyperalgesic properties of palmatine may involve the TNF pathway. Palmatine may be one of the compounds responsible for the anti-hyperalgesic and/or anti-arthritic properties of this medicinal plant. [ABSTRACT FROM AUTHOR]

A chemical composition analysis of the leachate in the process of producing alumina from fly ash using the acid method was conducted.Aluminum and iron were found to be the main elements in the leachate, with an aluminum concentration of 263.5 g/L (calculated as aluminum chloride) and a total iron concentration of 4.4 g/L (calculated as FeO), where the Fe2+ concentration was 2.17 g/L (calculated as FeO). A kinetic study on the oxidation of ferrous ions by air, oxygen-enriched gas, and ozone was carried out. Kinetic equations for the oxidation of ferrous ions by these 3 gaseous oxidants were obtained, and the oxidation rates were compared. The oxidation rate by ozone was found to be 1.7 times that of oxygen-enriched gas and 1.9 times that of air. [ABSTRACT FROM AUTHOR]

For many years, natural products have been recognised as an essential source of active components for medicinal medicines. Specifically, the application of active substances originated from plants and utilised in microbial natural goods dates back to a time before modern medicine. Natural product chemistry, biochemistry, and synthetic activities have long been linked to the effectiveness of natural products. Hence, the special qualities of these natural products are being utilised in light of scientific advancements in contemporary molecular and cellular biology, analytical chemistry, and pharmacology. The goal is to take advantage of the chemical and structural diversity, as well as the biodiversity, of these types of products in relation to their potential therapeutic effects. Rearranging chemical entities or structural isomers of naturally existing products to create new compounds is a common strategy used by drug design units to create novel molecules of interest that may be developed into therapeutics with potential. [ABSTRACT FROM AUTHOR]

The recognition of cerambycids as frequent and damaging invaders led to an increase in the interest in the chemical ecology of the group with the identification of pheromones and pheromone-like attractants for well over 100 species. Pheromone components of the Cerambycidae are often phylogenetically conserved, with a single compound serving as a pheromone component for several related species. In the subfamily Lamiinae, the compound 2-(undecyloxy)ethanol (monochamol) has been identified as an aggregation-sex pheromone for several species of the genus Monochamus. In other species, including Monochamus maculosus Haldeman, field trials have demonstrated that monochamol is a pheromone attractant, but at that point it was still unknown as to whether it was a pheromone for this species. Here we report the identification, and laboratory and field trials of a pheromone component produced by adult male M. maculosus. Chemical analyses of headspace volatile collections sampled from field collected beetles of both sexes revealed the presence of one male-specific compound that was identified as 2-(undecyloxy)ethanol. Electroantennography analyses showed that monochamol elicited responses from the antennae of female beetles. Traps baited with monochamol in the field captured M. maculosus adults of both sexes corroborating the identification of monochamol as the sex-aggregation pheromone of this species. The attractivity of monochamol to adult M. maculosus in our field trapping experiment was synergized by the addition of the host volatile α-pinene. [ABSTRACT FROM AUTHOR]

Context: The production of bioethanol from renewable raw materials is a decisive factor in the economic development of many countries. However, the complexity of the processes and the numerous experimental variables involved require a deeper understanding of the chemical reactions that take place during bioethanol production to define optimal parameters. Here, we have employed density functional theory–based calculations to investigate the local reactivity of oligomeric systems by considering crystalline and amorphous cellulose models to better understand some details regarding pulp pretreatment processes. Our results evidence a higher chemical susceptibility of amorphous portions of cellulose to chemicals typically employed in acid hydrolysis. Additionally, we observed that glucose monomers coming from cellulose hydrolysis may undergo oxidation, leading to the formation of byproducts such as hydroxymethylfurfural (HMF), acetic acid, formic acid, and levulinic acid. The analysis of local chemical softness indexes indicated that cellulose hydrolysis may be associated with intermediate chemical steps. Finally, we investigated the influence of distinct solvents (dielectric constants) on the local reactivity of the systems, evidencing a relevant role of the solvent dielectric constant for cellulose degradation in glucose. Methods: Initial three-dimensional structures were constructed. Pre-optimizations were performed in a Hartree–Fock (HF) approach employing the PM7 semi-empirical hamiltonian. The structures were then re-optimized via density functional theory (DFT). The local reactivity study of the systems was conducted through the condensed-to-atoms Fukui indexes (CAFI). Systematic changes of the dielectric constants were also considered in geometry optimization and CAFI calculations to estimate the influence of solvents on the reactivity of the systems. [ABSTRACT FROM AUTHOR]

There is increasing interest in the use of cannabidiol (CBD) as a potential therapeutic for alleviating chronic pain in cancer patients. Reliable determination of CBD content tailored to individual patients is essential for effective administration. Additionally, there is a growing need for rapid and portable detection methods for food products containing trace amounts of cannabis-derived compounds. Electrochemical technique offer a promising approach for fast and straightforward analytical identification of compounds like CBD. This study presents the fabrication of electrochemical sensor utilizing Fe2O3 quantum dots (QDs) – Co3O4 nanowires (NWs) as a sensing layer in a modified silver electrode. Chemical and structural analyses including energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis, and X-ray photoelectron spectroscopy (XPS) confirm the excellent decoration of Fe2O3 QDs on the Co3O4 NW surfaces. The Fe2O3 QDs-Co3O4 NWs exhibit electrochemical activity based on cyclic voltammetry (CV), chronoamperometry (CA), and differential pulse voltammetry (DPV) measurements. The sensor demonstrates a sensitivity of 1.21 mA•mM⁻¹•mm⁻¹ with strong linearity over the range of 0.02–0.1 mM (R2 = 0.9991) and a low detection limit of 0.67 µM. The enhanced electrochemical response of the Fe2O3 QDs-Co3O4 NWs sensing layer is attributed to the increased number of active sites resulting from the heterostructure formed by the two semiconductor crystals. A charge-transfer mechanism driven by stochastic processes is proposed to explain the electrochemical sensing behavior. [ABSTRACT FROM AUTHOR]

Seven new oleanane- type triterpene saponins, lysimaponins A-G, were isolated from aerial parts of Lysimachia laxa Baudo. Their chemical structures have been elucidated by analysis of spectroscopic and chemical methods. All compounds were evaluated for their antibacterial effects against Microcystis aeruginosa, Vibrio parahaemolyticus, V. harveyi, V. vulinificus, V. cholerae , and V. alginolyticus. All compounds showed potent antibacterial activities against the cyanobacteria M. aeruginosa with IC50 values ranging from 14.4 ± 1.2 to 35.3 ± 2.2 µg/mL. Compounds 1, 2, 4 - 7 inhibited V. parahaemolyticus with MIC values ranging from 64 to 256 µg/mL. The results suggested that saponins from L. laxa could be potential anti-cyanobacteria agents. [ABSTRACT FROM AUTHOR]

Some studies have used physical techniques for the assessment of bone structure and composition. However, very few studies applied multiple techniques, such as those described below, at the same time. The aim of our study was to determine the chemical and mineralogical/organic composition of bovine tibial bone samples using geophysical/geochemical reference techniques. X-ray diffraction (XRD), thermogravimetry (TG), Fourier-transform infrared spectrometry with attenuated total reflectance accessory (FTIR-ATR), inductively coupled mass spectrometry (ICP-MS) and inductively coupled optical emission spectrometry (ICP-OES) were applied to measure the organic and inorganic composition of 14 bovine bone samples. In addition, peripheral quantitative CT (QCT) was used to assess BMD in these bones. We were able to define the total composition of the studied bone samples. ICP-OES and ICP-MS techniques were used to determine the major and trace element composition. The X-ray analysis could detect inorganic crystalline compounds of bones, such as bioapatite, and its degree of ordering, indicating whether the bones belong to a younger or older individual. The total volatile content of the samples was calculated using TG and resulted in about 35 weight% (wt%). This, together with the 65 wt% total resulting from the chemical analysis (i.e., inorganic components), yielded a total approaching 100 wt%. As a large portion of the volatile content (H2O, CO2, etc.) was liberated from the organic components and, subordinately, from bioapatite, it could be concluded that the volatile-to-solid ratio of the examined bone samples was ~35:65. The FTIR-ATR analysis revealed that the organic portion consists of collagens containing amide groups, as their typical bands (OH, CH, CO, NC) were clearly identified in the infrared spectra. Numerous parameters of bone composition correlated with BMD as determined by QCT. In conclusion, we performed a complex evaluation of bovine bones to test multiple geophysical/geochemical techniques in bone research in association with QCT bone densitometry. From a medical point of view, the composition of the studied bones could be reliably examined by these methods. [ABSTRACT FROM AUTHOR]

This study investigates the effectiveness of various chemical methods, both ultrasound-assisted and non-assisted, for extracting cellulose from banana pseudostem (BPS) waste, comparing the results with commercial pine and eucalyptus cellulose fibers. Delignification treatments with NaOH (25% and 30%) and H2O2 (8%) were evaluated, applied with both conventional and focused sonication. Ultrasound-assisted methods, particularly with NaOH, achieved cellulose percentages as high as 99.5%. X-ray diffraction (XRD) analysis revealed that NaOH treatments significantly increased the cellulose crystallinity index, reaching up to 67.9%, surpassing commercial fibers. Scanning electron microscopy (SEM) results showed that NaOH treatments, especially at 30%, improved fiber morphology and exposure. Thermogravimetric analysis (TGA) indicated that methods using NaOH and focused sonication enhanced the thermal stability of the cellulose. Compared to commercial fibers, some samples obtained with the proposed methods demonstrated higher purity, yield, and thermal stability, highlighting the effectiveness of ultrasound-assisted and NaOH methods. [ABSTRACT FROM AUTHOR]

This study utilized a bobbin tool to friction stir weld aluminum 6082 workpieces under two sets of process parameters: a tool rotation speed of 280 rev/min with a weld velocity of 280 mm/min (280/280) and a tool rotation speed of 450 rev/min with a weld velocity of 450 mm/min (450/450). The weld microstructures were characterized through optical microscopy utilizing polarized light and through transmission electron microscopy (TEM) and scanning electron microscopy (SEM) coupled with chemical analysis by energy dispersive spectroscopy and electron back scatter diffraction. The microstructural studies were supplemented by hardness measurements (Vickers) performed on the same sections as the metallographic examinations. The produced weldments were free from cracks and any discontinuities. Fine, equiaxed grains that were several microns in size characterized the stir zones (SZs), and the advancing (AS) and retreating (RS) sides revealed distinct microstructural features. On the AS, the transition from the thermo-mechanically affected zone to the SZ was well defined and sharp, but on the RS, the transition appeared as a continuous, gradual change in microstructure. The lower weld energy (280/280) produced lower hardness in the stir zone than the higher energy weld (450/450), ~95 HV1 versus ~115 HV1; however, the 280/280 welds showed higher tensile strengths than the 450/450 welds, ~238 MPa as opposed to ~172 MPa. These behaviors in mechanical performance correlated with the temperature histories produced by each set of weld parameters in relation to the precipitation behavior of the alloy. The fracture characteristics of the weldments were notably different with the 450/450 sample fracturing in a quasi-brittle manner with slight plastic deformation and the 280/280 sample fracturing ductilely. A numerical simulation supported the investigation by elucidating the temperature and material flow behavior during the joining process. [ABSTRACT FROM AUTHOR]

The increasing awareness of environmental issues and the transition to green analytical chemistry (GAC) have gained popularity among academia and industry in recent years. One of the principles of GAC is the reduction and replacement of toxic solvents with more sustainable and environmentally friendly ones. This review gives an overview of the advances in applying green solvents as an alternative to the traditional organic solvents for peptide and protein purification and analysis by liquid chromatography (LC) and capillary electrophoresis (CE) methods. The feasibility of using greener LC and CE methods is demonstrated through several application examples; however, there is still plenty of room for new developments to fully realize their potential and to address existing challenges. Thanks to the tunable properties of designer solvents, such as ionic liquids and deep eutectic solvents, and almost infinite possible mixtures of components for their production, it is possible that some new designer solvents could potentially surpass the traditional harmful solvents in the future. Therefore, future research should focus mainly on developing new solvent combinations and enhancing analytical instruments to be able to effectively work with green solvents. [ABSTRACT FROM AUTHOR]

SUMMARY: Fucose‐rich sulfated polysaccharides such as fucoidans are primarily found in brown algae. These compounds possess interesting pharmacological perspectives for antiviral and antioxidant drug development. The brown alga Myriogloea major (Chordariaceae, Ectocarpales) is an endemic brown alga from Argentine Patagonia similar to other members of the Chordariaceae family used as a commercial source of fucoidans. In the present study, M. major was extracted with diluted hydrochloric acid (pH 2) solution in a protocol usually utilized for obtaining fucoidans. The dry weight from two extracts at different extraction stages (E1 and E2) represented 42% of the extracted dried biomass. Chemical analysis showed that the extracts contained between 15% (E2) and 20% (E1) of sulfate esters and approximately 80% of fucose constituents on their polysaccharides. The total phenolic content was lower than 1% (gallic acid equivalents). We analyzed the antioxidant activity of these extracts against the anti‐herpes simplex virus (HSV)‐1, HSV‐2 and bovine coronavirus. The antioxidant activity was lower than 50% at a concentration of 1 mg mL−1 in both extracts. Our findings demonstrate that, in the presence of these extracts, the viral adsorption and internalization were reduced by up to 75%. By applying its antiviral action to block the viral infection, the progeny virus released from host cells was significantly restricted, without affecting cell‐to‐cell spread of virus or virus viability. [ABSTRACT FROM AUTHOR]

Herein, a detailed experimental study of the crystallization of amorphous N‐doped Ge‐rich GeSbTe layers (GGSTN) when in contact with a polycrystalline GeSbTe (GST template is reported on. By combining in situ annealing in the transmission electron microscope and ex situ chemical analysis, it is shown that, as observed in many materials, the layer in contact with the crystalline template crystallizes at a lower temperature than needed for bulk crystallization. At surprise, this characteristic is not due to the solid‐phase epitaxy of the GGSTN on the crystalline GST template but to a decrease of the Ge content in the GGSTN layer. Indeed, during annealing, Ge diffuses from the amorphous layer into the crystalline GST layer where it gets trapped and forms grains which grow, eventually leading to the formation of a pure crystalline Ge layer. As a result of this Ge depletion, the thermal budget necessary to drive the phase separation limiting the crystallization of the remaining GGSTN alloy is smaller. [ABSTRACT FROM AUTHOR]

Herein, the operation of a GeSe ovonic threshold switch (OTS) is studied as a self‐selecting memory cell based on the polarity effect. From the observed operating current (Iop) dependence and area scaling behavior, the critical role of Joule heating in ensuring exceptionally large memory window in this material is confirmed. The underlying mechanism is further investigated by means of chemical analysis and is confirmed to be caused by polarity‐dependent atomic migration under high‐Iop regime, consistent with elemental segregation due to electronegativity contrast. More specifically, selective diffusion of Ge atoms through the TiN layer into negatively biased top electrode stack is observed. At the same time, there is no sign of a similar process for Se atoms under opposite voltage polarity. Based on these observations, a novel memory concept utilizing a selective diffusion barrier is proposed. Furthermore, under low‐Iop regime, no major composition change is observed, leaving room for alternative interpretation of the polarity effect under such conditions. Finally, it is demonstrated that functional GeSe OTS‐only memory is fabricated with atomic layer deposition, making it suitable for vertical 3D integration to enable low‐cost applications. [ABSTRACT FROM AUTHOR]

Performance‐enhancing heavy alkali‐based post‐deposition treatments (PDT) of Cu(In,Ga)Se2 (CIGSe) thin‐film solar cells absorbers often induce the formation of a Rb‐ In‐Se phase on the CIGSe absorber. Co‐evaporation of an interfacial RbInSe2 (RISe) layer between buffer and absorber can also benefit cell performance. A detailed analysis of the chemical interface structures in CdS/RISe/CIGSe layer stacks is performed using hard X‐ray photoelectron spectroscopy (HAXPES). For comparison, stacks without RISe and based on RbF PDT CIGSe absorbers are also studied. When aiming for the direct co‐evaporation of a RISe layer on the CIGSe absorber, the formation of an additional In‐Se phase is found. For the RbF PDT CIGSe absorbers, the study only finds small amounts of Rb and no indication for a RISe layer formation. Examining layer stacks prepared via additional chemical bath deposition (CBD) of CdS reveals a clear impact of the presence of Rb (or of Rb‐containing species) on the CIGSe surface. In these cases, an increase of the induction/coalescence period is found at the beginning of the CBD buffer layer growth process and the formation of Cd─Se bonds; thereafter, a more compact CdS layer growth is observed. [ABSTRACT FROM AUTHOR]

Food contact paperboard poses a potential risk of food contamination due to the possible release of chemicals (intentionally added or not), particularly in recycled paperboard. Water extractions were performed, according to wet food procedures, of paperboard samples collected from a manufacturer at the beginning and the end of a recycling production chain. Chemical analysis and hormonal activities in vitro of water extracts were studied. ICP–MS analysis confirmed the presence of 15 trace elements with lower concentrations after the recycling process, with the exception of chlorine. The chromatographic analyses demonstrated that the identified substances in the starting paperboard, before the recycling process, were approximately twice as high as in the end paperboard, after the recycling process. These substances included also natural wood products, chemical additives, and undesirable substances such as phthalates. Two major products (3,5-di-tert-butylphenol and methyl-2-pyrrolidone) were found in the starting and the end paperboard extracts, respectively. Two common substances were identified in both extracts: 2,4-di-tert-buthylphenol and dehydroabietic acid. Evaluation of potential endocrine disruption showed that the starting paperboard extract exhibited oestrogenic and antiandrogenic effects, while these effects nearly disappeared in the end paperboard extract. These results confirmed that the recycling process was effective in removing most of the contaminant substances. [ABSTRACT FROM AUTHOR]

Following the rapid developments in genomics and proteomics in recent decades, the analysis of the associated sugars became a critical center of interest, particularly in the field of analytical chemistry. Indeed, their synthetic route, diversity and complexity make these carbohydrates, and in particular glycosaminoglycans (GAG), a real analytical puzzle. These polymers are involved in a wide range of biological processes through their particular interaction with proteins. This article aims to show the contribution of separation sciences to the identification and characterization of interaction sites on GAGs. After a brief review of the structure and diversity of GAGs, the question was: do GAGs have a specific interaction motif with proteins? A literature review showed that this question is still controversial and that the reality is more nuanced. This review presents the different separative strategies used to try to identify such a specific GAG binding site if there is one. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of poly (diallyldimethylammonium chloride) (PDADMAC) and crystalline nanocellulose (CNC) on cassava starch-based film (CS), focusing on their structural, physicochemical, and antimicrobial properties. Three film types were analyzed: a control film (CS), a film with CS and PDADMAC (CS/PDADMAC), and films containing CS, CNC, and PDADMAC simultaneously (CS/CNC/PDADMAC). The opacity values were influenced (p < 0.05) by incorporating PDADMAC and CNC, decreasing film transparency. Furthermore, due to its hydrophilic characteristics, an increase in water vapor permeability (WVP) values of 86.57–111.6% was observed by incorporating PDADMAC and CNC compared to CS film, respectively. SEM revealed that all films had smooth surfaces without cracks. Furthermore, FTIR analysis confirmed chemical interactions between the film's constituent polymers. Notably, the tensile strength (TS) improved significantly with the addition of CNC, with a notable increase of 82.1% compared to the other films. Furthermore, the CS/CNC/PDADMAC film exhibited antiviral activity, inactivating 90–99.9% of the MHV-3 coronavirus within 1 and 1440 min of direct contact. This film also demonstrated effective inhibition against Staphylococcus aureus and Escherichia coli bacteria. The film attains its antimicrobial effect through electrostatic interaction involving the quaternary ammonium groups of PDADMAC and the phospholipid membrane of the microorganism. Therefore, this study promotes an innovative approach to reduce the spread of pathogens through potential contamination on plastic film surfaces. [ABSTRACT FROM AUTHOR]

Small‐molecule receptors are increasingly employed to probe various functional groups for (bio)chemical analysis. However, differentiation of polyfunctional analogs sharing multiple functional groups remains challenging for conventional mono‐ and bidentate receptors because their insufficient number of binding sites limits interactions with the least reactive yet property‐determining functional group. Herein, we introduce 6‐thioguanine (TG) as a supramolecular receptor for unique tridentate receptor‐analyte complexation, achieving ≥97 % identification accuracy among 16 polyfunctional analogs across three classes: glycerol derivatives, disubstituted propane, and vicinal diols. Crucially, we demonstrate distinct spectral changes induced by the tridentate interaction between TG's three anchoring points and all the analyte's functional groups, even the least reactive ones. Notably, hydrogen bond (H‐bond) networks formed in the TG‐analyte complexes demonstrate additive effects in binding strength originating from good bond linearity, cooperativity, and resonance, thus strengthening complexation events and amplifying the differences in spectral changes induced among analytes. It also enhances spectral consistency by selectively forming a sole configuration that is stronger than the respective analyte‐analyte interaction. Finally, we achieve 95.4 % accuracy for multiplex identification of a mixture consisting of multiple polyfunctional analogs. We envisage that extension to other multidentate non‐covalent interactions enables the development of interference‐free small molecule‐based sensors for various (bio)chemical analysis applications. [ABSTRACT FROM AUTHOR]

We investigate the inhibition mechanism between pomotrelvir and the SARS‐CoV‐2 main protease using molecular mechanics and quantum mechanics/molecular mechanics simulations. Alchemical transformations where each Pi group of pomotrelvir was transformed into its counterpart in nirmatrelvir were performed to unravel the individual contribution of each group to the binding and reaction processes. We have shown that while a γ‐lactam ring is preferred at position P1, a δ‐lactam ring is a good alternative for the design of inhibitors for variants presenting mutations at position 166. For the P2 position, tertiary amines are preferred with respect to secondary amines. Flexible side chains at the P2 position can disrupt the preorganization of the active site, favouring the exploration of non‐reactive conformations. The substitution of the P2 group of pomotrelvir by that of nirmatrelvir resulted in a compound, named as C2, that presents a better binding free energy and a higher population of reactive conformations in the Michaelis complex. Analysis of the chemical reaction to form the covalent complex has shown a similar reaction mechanism and activation free energies for pomotrelvir, nirmatrelvir and C2. We hope that these findings could be useful to design better inhibitors to fight present and future variants of the SARS‐CoV‐2 virus. [ABSTRACT FROM AUTHOR]

When undertaking any review of the structure of the hair and its mechanical properties it becomes apparent that the overall behaviour of keratin fibres is commonly attributed to the presence of hydrogen, disulfide and ionic bonds. The action of physico‐chemical agents used during various cosmetic treatments is viewed as the result of an interaction with these bonds. Thus, the breaking of bonds by chemical agents, or via mechanical or thermal stresses, affects the relative balance of disulfide and hydrogen bonds and the contribution of hydrophobic interactions, which are all important factors that may alter hair behaviour. Generally, these chemical bonds are considered as responding homogeneously to the environmental and cosmetic factors. This unitary image is challenged, however, by evaluating the results of chemical, nanomechanical, tensile and thermal measurements, which suggest that disulfide bonds may be grouped into several types, according to their location within the fibre and the way they respond to various agents. A compensatory effect of newly formed hydrogen bonds for broken disulfide bonds may also be seen, and additionally involves different types of hydrogen bonds. As a result, the picture of chemical bonding in hair appears to be far from a homogeneous one. In addition, it is apparent that further investigation is required for clarifying the action of ionic bonds and hydrophobic interactions within the hair fibre. The present review aims, thus, at offering a deeper background for understanding how the hair behaves under various conditions. [ABSTRACT FROM AUTHOR]

Objective: Tyrosinase inhibitors suppress melanogenesis in melanocytes. During a screening for tyrosinase inhibitors, however, we noticed some discrepancies in inhibitory efficacies between melanocytes and in vitro assays. The compound (S)‐N‐{3‐[4‐(dimethylamino)phenyl]propyl}‐N‐methyl‐indan‐1‐amine (GIF‐2115) exerts antioxidative stress activity upon accumulation in late endosomes and lysosomes. GIF‐2115 was also identified as a potent antimelanogenic reagent in B16F10 mouse melanoma cells. GIF‐2115 inhibited the activity of mushroom tyrosinase and the lysates of B16F10 cells. However, structure–activity relationship studies indicated that GIF‐2238, which lacks the benzene ring in the aminoindan structure of GIF‐2115, inhibited tyrosinase activity in vitro but did not inhibit melanogenesis in B16F10 cells. The aim of the present study is to show the importance of the intracellular distribution of tyrosinase inhibitors in exerting their antimelanogenic activity in melanocytes. Methods: The intracellular distribution of compounds was monitored by linking with the fluorescent group of 7‐nitro‐2,1,3‐benzoxadiazole (NBD). To mislocalize GIF‐2115 to mitochondria, the mitochondria‐preferring fluoroprobe ATTO565 was used. Results: We reconfirmed the localization of GIF‐2250 (GIF‐2115‐NBD) not only to matured but also to early‐stage melanosomes. Although GIF‐2286 (GIF‐2238‐NBD) maintained tyrosinase inhibitory activity, it did not show specific intracellular localization. Moreover, when GIF‐2115 was linked with ATTO565, the resultant compound GIF‐2265 did not inhibit melanogenesis in B16F10 cells, despite its strong tyrosinase inhibitory activity. Conclusion: These results suggest that melanosomal localization is essential for the antimelanogenic activity of GIF‐2115, and GIF‐2115 derivatives may be new guides for drugs to endosomes and lysosomes as well as melanosomes. [ABSTRACT FROM AUTHOR]

The study explored the chemical composition, antioxidant activity, and potential antihyperlipidemic effects of Allspice (Pimenta dioica) leaf essential oil. The oil yield from hydro-distillation was 1.61 ± 0.35% (v/w), with major compounds identified by GC-MS analysis as eugenol (72.06 ± 3.93%), β-pinene (9.29 ± 3.33%), chavicol (6.95 ± 0.6%), limonene (3.05 ± 0.71%), and 3-octenol (1.55 ± 1.07%). The oil's antioxidant activity (426 ± 3.5 mg TE g−1) was attributed to polyphenols. It also reduced porcine pancreatic lipase activity, suggesting potential in managing dietary lipids. Molecular docking showed strong binding to CES1, with eugenol, limonene, β-pinene, and octenol outperforming the control (probucol). ADME-Tox predictions indicated favorable pharmacological profiles with controlled lipophilicity and toxicity. [ABSTRACT FROM AUTHOR]

Snake venoms are complex mixtures majorly composed of proteins with well-studied biological effects. However, the exploration of non-protein components, especially lipids, remains limited despite their potential for discovering bioactive molecules. This study compares three liquid–liquid lipid extraction methods for both chemical and biological analyses of Bothrops moojeni snake venom. The methods evaluated include the Bligh and Dyer method (methanol, chloroform, water), considered standard; the Acunha method, a modification of the Bligh and Dyer protocol; and the Matyash method (MTBE/methanol/water), featuring an organic phase less dense than the aqueous phase. Lipidomic analysis using liquid chromatography with high-resolution mass spectrometry (LC-HRMS) system revealed comparable values of lipid constituents' peak intensity across different extraction methods. Our results show that all methods effectively extracted a similar quantity of lipid species, yielding approximately 17–18 subclasses per method. However, the Matyash and Acunha methods exhibited notably higher proportions of biologically active lipids compared to the Bligh and Dyer method, particularly in extracting lipid species crucial for cellular structure and function, such as sphingomyelins and phosphatidylinositol-phosphate. In conclusion, when selecting a lipid extraction method, it is essential to consider the study's objectives. For a biological approach, it is crucial to evaluate not only the total quantity of extracted lipids but also their quality and biological activity. The Matyash and Acunha methods show promise in this regard, potentially offering a superior option for extracting biologically active lipids compared to the Bligh and Dyer method. [ABSTRACT FROM AUTHOR]