Non-volatile Organic Compounds Research Articles

A strategy to distinguish similar traditional Chinese medicines by liquid chromatography-mass spectrometry, electronic senses, and gas chromatography-ion mobility spectrometry: Marsdeniae tenacissimae Caulis and Paederiae scandens Caulis as examples.

Marsdeniae tenacissimae Caulis (MTC), a popular traditional Chinese medicine, has been widely used in the treatment of tumor diseases. Paederiae scandens Caulis (PSC), which is similar in appearance to MTC, is a common counterfeit product. It is difficult for traditional methods to effectively distinguish between MTC and PSC. Therefore, there is an urgent need for a rapid and accurate method to identify MTC and PSC. The aim is to distinguish between MTC and PSC by analyzing the differences in nonvolatile organic compounds (NVOCs), taste, odor, and volatile organic compounds (VOCs). Liquid chromatography-mass spectrometry (LC-MS) was utilized to analyze the NVOCs of MTC and PSC. Electronic tongue (E-tongue) and electronic nose (E-nose) were used to analyze their taste and odor respectively. Gas chromatography-ion mobility spectrometry (GC-IMS) was applied to analyze VOCs. Finally, multivariate statistical analyses were conducted to further investigate the differences between MTC and PSC, including principal component analysis, orthogonal partial least squares discriminant analysis, discriminant factor analysis, and soft independent modeling of class analysis. The results of this study indicate that the integrated strategy of LC-MS, E-tongue, E-nose, GC-IMS, and multivariate statistical analysis can be effectively applied to distinguish between MTC and PSC. Using LC-MS, 25 NVOCs were identified in MTC, while 18 NVOCs were identified in PSC. The major compounds in MTC are steroids, while the major compounds in PSC are iridoid glycosides. Similarly, the distinct taste difference between MTC and PSC was precisely revealed by the E-tongue. Specifically, the pronounced bitterness in PSC was proven to stem from iridoid glycosides, whereas the bitterness evident in MTC was intimately tied to steroids. The E-nose detected eight odor components in MTC and six in PSC, respectively. The subsequent statistical analysis uncovered notable differences in their odor profiles. GC-IMS provided a visual representation of the differences in VOCs between MTC and PSC. The results indicated a relatively high relative content of 82 VOCs in MTC, contrasted with 32 VOCs exhibiting a similarly high relative content in PSC. In this study, for the first time, the combined use of LC-MS, E-tongue, E-nose, GC-IMS, and multivariate statistical analysis has proven to be an effective method for distinguishing between MTC and PSC from multiple perspectives. This approach provides a valuable reference for the identification of other visually similar traditional Chinese medicines.

Three-Dimensional evaporator for simultaneous VOC removal and clean water production

Interfacial solar steam generation (ISSG) is a promising and sustainable technology to product clean water, but most of current evaporators suffer the failure to remove volatile organic compounds (VOCs) from condensate water and prevent the production of concentrated water. Herein, we proposed a three-dimensional bi-functional evaporator integrating ISSG with heterogeneous Fenton technology, simultaneously to remove various organics from both condensate water and feed water. The evaporator (rGO-FeOOH@MF) was prepared by loading reduced graphene oxide (rGO) and hydroxy-ferric oxide (FeOOH) nanoparticles onto melamine foam (MF). The results manifested that rGO-FeOOH@MF exhibited an outstanding evaporation flux of 2.20 kg m-2h-1 under one sun irradiation. More importantly, the removal rate of VOC in condensate water reached 92.56 ± 0.11 % due to synergetic Fenton reaction, which was 4 times (23.1 %) than that of sole ISSG. Meanwhile, the VOC removal rate remained ∼92 % even after 7 times cycle tests, demonstrating the evaporator with a good stability. The rGO-FeOOH@MF was also proved to be able to remove VOCs from high saline wastewater (96.43 %). Besides, for the purification of concentrated water, the evaporator achieved ∼100 % removal rates for non-volatile organic compounds. To sum up, the prepared rGO-FeOOH@MF evaporator opens a new way to simultaneous removal of non-volatile and volatile contaminants in wastewater treatment field.

New perspectives on ‘Breathomics’: metabolomic profiling of non-volatile organic compounds in exhaled breath using DI-FT-ICR-MS

Breath analysis offers tremendous potential for diagnostic approaches, since it allows for easy and non-invasive sample collection. “Breathomics” as one major research field comprehensively analyses the metabolomic profile of exhaled breath providing insights into various (patho)physiological processes. Recent research, however, primarily focuses on volatile compounds. This is the first study that evaluates the non-volatile organic compounds (nVOCs) in breath following an untargeted metabolomic approach. Herein, we developed an innovative method utilizing a filter-based device for metabolite extraction. Breath samples of 101 healthy volunteers (female n = 50) were analysed using DI-FT-ICR-MS and biostatistically evaluated. The characterisation of the non-volatile core breathome identified more than 1100 metabolites including various amino acids, organic and fatty acids and conjugates thereof, carbohydrates as well as diverse hydrophilic and lipophilic nVOCs. The data shows gender-specific differences in metabolic patterns with 570 significant metabolites. Male and female metabolomic profiles of breath were distinguished by a random forest approach with an out-of-bag error of 0.0099. Additionally, the study examines how oral contraceptives and various lifestyle factors, like alcohol consumption, affect the non-volatile breathome. In conclusion, the successful application of a filter-based device combined with metabolomics-analyses delineate a non-volatile breathprint laying the foundation for discovering clinical biomarkers in exhaled breath.

Controlled construction of 2D hierarchical core-shell ZnO/MnO2 nanosheets on Nitinol fiber with enhanced adsorption performance for selective solid-phase microextraction of trace polycyclic aromatic hydrocarbons in water samples

BackgroundPolycyclic aromatic hydrocarbons (PAHs) are an important class of potentially toxic persistent organic pollutants in environmental water. Their concentrations are usually too low to allow for direct determination with analytical instruments, and the preconcentration is required prior to instrumental analysis. Solid phase microextraction (SPME) is considered as a high-performance green sample preparation technique for volatile and non-volatile organic compounds due to its high enrichment factor. In fact, the nature of SPME coatings governs the adsorption performance. Therefore, more efforts have devoted to the controlled construction of novel long-life SPME fibers with enhanced adsorption performance and improved adsorption selectivity. Results2D hierarchical core-shell ZnO/MnO2 nanosheets (NSs) were constructed on a Nitinol (NiTi) fiber substrate by layer-by-layer assembly for enhanced and selective SPME of PAHs. Firstly, hexagonal ZnO NSs were electrodeposited on the NiTi substrate. Subsequently smaller secondary MnO2 NSs were uniformly grown on the surface of ZnO NSs by a facile hydrothermal oxidation process. ZnO NSs were well protected by the chemically stable MnO2 shell, making the coating highly durable and efficient for SPME application. Meanwhile, the ZnO/MnO2 NSs coating demonstrated superior adsorption performance for PAHs. After the optimization of SPME conditions, the proposed SPME-HPLC-UV method exhibited good analytical performance for preconcentrating and determining trace PAHs with wide linear ranges (0.03–200 μg L−1) and low LODs (0.005–0.112 μg L−1) as well as good repeatability (1.4%-6.9%) and fiber-to-fiber reproducibility (5.3%-7.1%). Moreover, the proposed method showed good precision and recovery in the preconcentration and determination of target PAHs in real water samples. SignificanceAs compared with representative commercially available fibers, the NiTi@ZnO/MnO2 NSs fiber showed enhanced adsorption efficiency and improved adsorption selectivity for PAHs. The constructed fiber can be used as an alternative to commercial fibers for the adsorption and preconcentration of target PAHs in the environmental water samples. Moreover, the preparation strategy is expected to provide new insights into the precisely controlled construction of the efficient and stable core-shell bimetallic oxide nanostructures on the superielastic NiTi-based fibers.

Comprehensive multicomponent characterization and quality assessment of Xiaoyao Wan by UPLC-Q-Orbitrap-MS, HS-SPME-GC-MS and HS-GC-IMS

Xiaoyao Wan (XYW) is a prescription medicine of traditional Chinese medicine (TCM) with the effects of “soothing the liver and relieving depression,” and “strengthening spleen and nourishing blood”. XYW has been widely concerned in the treatment of depression and has become one of the commonly used classic formulas in clinical practice. However, the pharmacodynamic substance basis and the quality control studies of XYW are hitherto quite limited. Here, we aim to fully utilize an advanced ultra – performance liquid chromatography-quadrupole – Orbitrap mass spectrometry (UPLC-Q-Orbitrap-MS), headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) technique to deep characterization of the pharmacological substance basis and quantitatively evaluate the quality of XYW. Firstly, 299 compounds were identified or tentatively characterized, including 198 non-volatile organic compounds (n-VOCs) and 101 volatile organic compounds (VOCs). Secondly, principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used to analyze quality differences in XYW at different manufacturers. Thirdly, a parallel reaction monitoring (PRM) method was established and validated to quantify the fourteen major effective substances in different manufacturers of XYW, which were chosen as the benchmarked substances to evaluate the quality of XYW. In conclusion, this study shows that the strategy provides a useful method for quality control of TCM and offers a practical workflow for exploring the quality consistency of TCM.

Fungal Cultivars of Higher Attine Ants Promote Escovopsis Chemotropism.

In varied environments, microorganisms search for partners or nutritional resources using chemical signals. Microbes are drawn (chemotaxis) or grow directionally (chemotropism) towards the chemical source, enabling them to establish and maintain symbiosis. The hypocrealean fungi Escovopsis enhance their growth towards the basidiomycete fungus Leucoagaricus gongylophorus, which is cultivated by leaf-cutting attine ants for food. Although directional growth is well documented in this symbiosis, it is unclear whether non-volatile or volatile organic compounds participate in the interaction between cultivar and Escovopsis, and which specific chemical compounds might attract and induce chemotropism. In this study, we examined the growth responses of Escovopsis isolates to non-volatile and volatile organic compounds produced by fungal cultivars of higher attine ants. We also isolated and identified molecules released by the ant-cultivar and assessed the chemotropism of Escovopsis towards them. Our results indicate that the growth of Escovopsis is stimulated in the presence of both non-volatile and volatile compounds from fungal cultivars. We also identified three isomeric diketopiperazines molecules from crude extracts of the ant cultivar, suggesting that these might play a role in Escovopsis chemotropism. Our findings provide insights into the complex chemical interactions that govern the association between Escovopsis and fungal cultivars.

Sensory Perception and Consumer Acceptance of Carrot Cultivars Are Influenced by Their Metabolic Profiles for Volatile and Non-Volatile Organic Compounds.

Sensory parameters as well as the volatile and non-volatile compound profiles of sixteen carrot cultivars were recorded to obtain insight into consumer preference decisions. The sensory test was carried out with a consumer panel of 88 untrained testers allowing a clear acceptance-based differentiation of the cultivars. Five individual sensory characters (sweetness, overall aroma, bitterness, astringency and off-flavor) supported this discrimination. Chemical analyses of volatile organic compounds, polyacetylenes, phenylpropanoids and sugars enabled us to correlate the influence of these ingredients on sensory perception. Higher concentrations of α-pinene, hexanal, styrene and acetophenone correlated with a better acceptance, as well as sweetness and overall aroma perception. In contrast, a low acceptance as well as a stronger perception of bitterness, astringency and off-flavor correlated with enhanced concentrations of camphene, bornylacetate, borneol, myristicine, falcarindiol, falcarindiol-3-acetate, laserin and epilaserin. The present study should support the development of new breeding strategies for carrot cultivars that better satisfy consumer demands.

Molecular and functional characterization of chemosensory genes from the root-knot nematode Meloidogyne graminicola

BackgroundRoot-knot nematode Meloidogyne graminicola has emerged as a major threat in rice agroecosystems owing to climate change-induced changes in cultivation practices. Synthetic nematicides are continually being withdrawn from the nematode management toolbox because of their ill effects on the environment. A sustainable strategy would be to develop novel nematicides or resistant plants that would target nematode sensory perception, which is a key step in the host finding biology of plant-parasitic nematodes (PPNs). However, compared to the extensive literature on the free-living nematode Caenorhabditis elegans, negligible research has been performed on PPN chemosensory biology.ResultsThe present study characterizes the five chemosensory genes (Mg-odr-7, Mg-tax-4, Mg-tax-4.1, Mg-osm-9, and Mg-ocr-2) from M. graminicola that are putatively associated with nematode host-finding biology. All the genes were highly transcribed in the early life stages, and RNA interference (RNAi)-induced downregulation of each candidate gene perturbed the normal behavioural phenotypes of M. graminicola, as determined by examining the tracking pattern of juveniles on Pluronic gel medium, attraction to and penetration in rice root tip, and developmental progression in rice root. In addition, a detrimental effect on nematode chemotaxis towards different volatile and nonvolatile organic compounds and host root exudates was documented.ConclusionOur findings enrich the existing literature on PPN chemosensory biology and can supplement future research aimed at identifying a comprehensive chemosensory signal transduction pathway in PPNs.

Identification of nonvolatile organic compounds (NVOCs) in biopharmaceuticals through non-target analysis and quantification using complexation-precipitation extraction

Single-use systems in biopharmaceutical manufacturing can potentially release chemical constituents (leachables) into drug products. Prior to conducting toxicological risk assessments, it is crucial to establish the qualitative and quantitative methods for these leachables. In this study, we conducted a comprehensive screening and structure elucidation of 23 leachables (nonvolatile organic compounds, NVOCs) in two antibody drugs using multiple (self-built and public) databases and mass spectral simulation. We identified 7 compounds that have not been previously reported in medical or medicinal extractables and leachables. The confidence levels for identified compounds were classified based on analytical standards, literature references, and fragment assignments. Most of the identified leachables were found to be plasticizers, antioxidants, slip agents or polymer degradants. Polysorbate (namely Tween) is commonly used as an excipient for protein stabilization in biopharmaceutical formulations, but its ionization in liquid chromatography-electrospray ionization mass spectrometry can interfere with compound quantification. To address this, we employed a complexation-precipitation extraction method to reduce polysorbate content and quantify the analytes. The developed quantitative method for target NVOCs demonstrated high sensitivity (limit of quantification: 20 or 50 μg/L), accuracy (recoveries: 77.2 to 109.5 %) and precision (RSD ≤ 8.2 %). Overall, this established method will facilitate the evaluation of NVOC safety in drug products.

Biomolecule repository of endophytic bacteria from guava serves as a key player in suppressing root- knot nematode, Meloidogyne enterolobii

Guava production in India is hampered by invasion of guava root knot nematode, Meloidogyne enterolobii. Biological control of plant parasitic nematodes is the best strategy to quench the soil and root population of nematodes. Hence the attempts were made to dissect the endophytic bacteria from various niche of guava plants. Amongst the various endophytic bacteria's, Klebsiella quasivaricola inhibited the egg hatching (100%) and moratlity of juveniles (100%). Exploration of non-volatile organic compounds of K. quasivaricola exhibited the presence of 2″-terthiophene, 9′spirobifluorenone, 4-Cyanophenyl 4-butylbenzoate, Benzoic acid, Benzoyl chloride, 3-phenyl-1, 2, 4-triazolin-5-one, Ethanone, 2,3-dihydro-5‑methoxy-, Ethanone, Trifluoroacetophenone, 6,12-dinaphthylindolo[3,2-b] carbazole having anti-microbial activities. Considering this, molecular docking experiments were carried out with important proteins of M. enterolobii such as Translationally Controlled Tumour Proteins, pectate lyase, phospholipase, hexokinase and Sphingomyelinase to understand the effect of biomolecules from K. quasivaricola. The results indicated that all biomolecules had prominent effect on different protein targets and in specific binding affinity with amino acid residues of protein targets benzoic acid, 4-Cyanophenyl 4-butylbenzoate, Trifluoroacetophenone, 6,12-dinaphthylindolo[3,2-b]carbazole, 3-phenyl-1,2,4-triazolin-5-one had significant effect on aforementioned protein targets of M. enterolobii. In addition, bio-hardened guava plants with the effective bacterial endophytes were challenged with M. enterolobii showcased 80% increase on plant growth parameters and 70% reduction of egg mass over control. Hence the present study gave limelight to explore the novel biomolecules from endophytic bacterium which could serve as an alternative synthetic nematicides for the management of M. enterolobii.

Real-Time Phytoncide Monitoring in Forests: A Comparative Study of SIFT-MS and Conventional GC-MS Methods

Conventional gas chromatography-mass spectrometry (GC-MS) analysis methods for measuring the concentration of phytoncides in forests are limited because of the need for an extended human presence in forests, the risk of errors, and contamination. To overcome these issues, this study introduces real-time measurement devices and selected ion flow tube mass spectrometry (SIFT-MS) as potential replacements. This study was conducted in the Hongneung Experimental Forest between 19 and 21 November 2019. A correlation analysis and independent samples t-test were performed to compare the GC-MS and SIFT-MS techniques. The diurnal patterns and trends in the phytoncide concentrations analyzed using the GC-MS and SIFT-MS methods were similar, suggesting the potential replacement of GC-MS with SIFT-MS. While both methods revealed similar major components in the daytime nonvolatile organic compounds (NVOCs), with pinenes comprising approximately half of the total percentage, the 24 h SIFT-MS analysis indicated reduced proportions of pinenes and benzaldehyde, along with the detection of more diverse NVOC compounds at night. Additionally, the studies indicated that GC-MS exhibited slightly higher selectivity, resulting in the detection of fewer NVOC compounds with SIFT-MS. The correlation analysis between the microclimate indicators and phytoncide measurement methods revealed differences: GC-MS with a mini pump showed positive correlations with fine dust and industrially derived VOCs, while the 24 h real-time measurements exhibited strong negative correlations. Consequently, while the GC-MS and SIFT-MS methods exhibited both similarities and differences in phytoncide concentrations, an independent samples t-test, confirming no statistically significant differences between the two methods, suggests the suitability of adopting SIFT-MS over GC-MS for phytoncide collection and analysis in forest environments. Nevertheless, this study contributes to the literature by comparing outdoor phytoncide levels using the GC-MS and SIFT-MS methodologies. These findings, which show that the methods are closely aligned, can guide future researchers in considering SIFT-MS equipment for phytoncide studies, offering a more accessible and efficient option with real-time capabilities.

Multifunctional solar water harvester with high transport selectivity and fouling rejection capacity

Shortage of clean water continues to grow around the world, and the recent solar-powered interfacial system has emerged as a sustainable, efficient and CO2-neutral approach to produce clean water. However, complex contaminants in surface water accompanied with environment pollution set huge obstacles for harvesting clean water via previous strategies. Here we develop a solar-powered graphene/alginate hydrogel (GAH)-based clean water extractor of super resistance to the transport of complex contaminants and ultra-antifouling capacity. This GAH features a high selectivity in water transport by rejecting >99.5% of volatile organic compounds, >99.3% of ions (Na+, Mg2+, K+ and Ca2+) and 100% of non-volatile organic compounds and bacteria; meanwhile, GAH is capable of rejecting oil adhesion by forming a large contact angle >140° under water, deactivating nearly 100% bacteria on surface and preventing salt crystallization. Given such promising adaptability to a wide environment, this GAH can directly convert surface water of complex components into safe drinkable water.

Global Anthropogenic Emissions of Full-Volatility Organic Compounds.

Traditional global emission inventories classify primary organic emissions into nonvolatile organic carbon and volatile organic compounds (VOCs), excluding intermediate-volatility and semivolatile organic compounds (IVOCs and SVOCs, respectively), which are important precursors of secondary organic aerosols. This study establishes the first global anthropogenic full-volatility organic emission inventory with chemically speciated or volatility-binned emission factors. The emissions of extremely low/low-volatility organic compounds (xLVOCs), SVOCs, IVOCs, and VOCs in 2015 were 13.2, 10.1, 23.3, and 120.5 Mt, respectively. The full-volatility framework fills a gap of 18.5 Mt I/S/xLVOCs compared with the traditional framework. Volatile chemical products (VCPs), domestic combustion, and on-road transportation sources were dominant contributors to full-volatility emissions, accounting for 30, 30, and 12%, respectively. The VCP and on-road transportation sectors were the main contributors to IVOCs and VOCs. The key emitting regions included Africa, India, Southeast Asia, China, Europe, and the United States, among which China, Europe, and the United States emitted higher proportions of IVOCs and VOCs owing to the use of cleaner fuel in domestic combustion and more intense emissions from VCPs and on-road transportation activities. The findings contribute to a better understanding of the impact of organic emissions on global air pollution and climate change.

Exploring the link between coffee matrix microstructure and flow properties using combined X-ray microtomography and smoothed particle hydrodynamics simulations

Coffee extraction involves many complex physical and transport processes extremely difficult to model. Among the many factors that will affect the final quality of coffee, the microstructure of the coffee matrix is one of the most critical ones. In this article, we use X-ray micro-computed (microCT) technique to capture the microscopic details of coffee matrices at particle-level and perform fluid dynamics simulation based on the smoothed particle hydrodynamics method (SPH) with the 3D reconstructured data. Information like flow permeability and tortuosity of the matrices can be therefore obtained from our simulation. We found that inertial effects can be quite significant at the normal pressure gradient conditions typical for espresso brewing, and can provide an explanation for the inconsistency of permeability measurements seen in the literature. Several types of coffee powder are further examined, revealing their distinct microscopic details and resulting flow features. By comparing the microCT images of pre- and post-extraction coffee matrices, it is found that a decreasing porosity profile (from the bottom-outlet to the top-inlet) always develops after extraction. This counterintuitive phenomenon can be explained using a pressure-dependent erosion model proposed in our prior work. Our results reveal not only some important hydrodynamic mechanisms of coffee extraction, but also show that microCT scan can provide useful microscopic details for coffee extraction modelling. MicroCT scan establishes the basis for a data-driven numerical framework to explore the link between coffee powder microstructure and extraction dynamics, which is the prerequisite to study the time evolution of both volatile and non-volatile organic compounds and then the flavour profile of coffee brews.

An Exploration of Dynamic Changes in the Mulberry Growth Process Based on UPLC-Q-Orbitrap-MS, HS-SPME-GC-MS, and HS-GC-IMS.

This work was designed to investigate the dynamic changes process of non-volatile organic compounds (n-VOCs) and volatile organic compounds (VOCs) in mulberries during different growth periods using UPLC-Q-Orbitrap-MS, HS-SPME-GC-MS, and HS-GC-IMS. A total of 166 compounds were identified, including 68 n-VOCs and 98 VOCs. Furthermore, principal component analysis (PCA), random forest analysis (RFA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to analyze differences in mulberries at different ripening stages. A total of 74 compounds appeared or disappeared at different ripening periods and 24 compounds were presented throughout the growth process. Quantitative analysis and antioxidant experiments revealed that as the mulberries continued to mature, flavonoids and phenolic acids continued to increase, and the best antioxidant activity occurred from stage IV. Conclusively, an effective strategy was established for analyzing the composition change process during different growth periods, which could assist in achieving dynamic change process analysis and quality control.

Biocontrol Efficiency of Rhizospheric Bacillus against the Plant Pathogen Fusarium oxysporum: A Promising Approach for Sustainable Agriculture

Among plant disease management strategies, biological control is a sustainable alternative to the use of chemicals for the control of vascular wilt caused by Fusarium oxysporum. Fusarium wilt is the most devastating disease affecting a wide variety of plants. Bacillus species are the most widely used biological control candidates for the control of these fungal diseases. This review describes the pathogenicity of F. oxysporum, its virulence mechanisms, and host plant–pathogen interactions. The control means deployed by Bacillus species inhibit or kill these phytopathogens. Bacillus spp. produce a wide range of secondary metabolites, including volatile and non-volatile organic compounds. Biocontrol potential is achieved through direct antimicrobial activity, the induction of the host plant’s immune response (Induced Systemic Resistance), and competition for nutrients and space. In addition, parameters governing the selection of effective biocontrol agents and their survival in plant microbial communities are discussed. The influence of the microbiota on the establishment and development of biocontrol agents can assess the potential of these treatments and facilitate the development of effective biopesticides during their field application.

Authentication of recycled and virgin polyethylene terephthalate based on UPLC-Q-TOF-MS using non-volatile organic compounds and chemometrics

Plastic packaging waste, such as polyethylene terephthalate (PET) has increased significantly in recent decades, arousing a considerable and serious public concern regarding the environment, economy, and policy. Plastic recycling is a useful tool to mitigate this issue. Here, a feasible study was performed to investigate the potential of a novel method for identifying virgin and recycled PET. Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was combined with various chemometrics, as a simple and reliable method that achieved a high discrimination rate for 105 batches of virgin PET (v-PET) and recycled PET (r-PET) based on 202 non-volatile organic compounds (NVOCs). Making use of orthogonal partial least-squares discrimination analysis (OPLS-DA) together with non-parametric tests, 26 marker compounds (i.e. 12 intentionally added substances (IAS) and 14 non-intentionally added substances (NIAS) as well as 31 marker compounds (i.e. 11 IAS and 20 NIAS) obtained from positive and combination of positive and negative ionization modes of UPLC-Q-TOF-MS, respectively, were successfully identified. Moreover, 100% accuracy was obtained using a decision tree (DT). Cross-discrimination based on misclassified samples using various chemometrics allowed the prediction accuracy to be improved and to identify a large sample set, thus greatly enhancing the application scope of this method. The possible origins of these detected compounds can be the plastic itself, as well as contamination from food, medicine, pesticides, industry-related substances, and degradation and polymerization products. As many of these compounds are toxic, especially those pesticide related, this indicates an urgent requirement for closed loop recycling. Overall, this analytical method provides a quick, accurate, and robust way to distinguish virgin from recycled PET and thus addresses the issue of potential virgin PET adulteration thereby detecting fraud in the area of PET recycling.

A comparative profile of urinary scent signals of two endangered Japanese populations of leopard cat

Two subspecies of mainland leopard cats (Prionailurus bengalensis), Iriomote cats (Prionailurus bengalensis iriomotensis), and Tsushima leopard cats (Prionailurus bengalensis euptilurus), are small, endangered felids that are endemic to the Japanese islands, Iriomote-jima and Tsushima, respectively. Both subspecies have an estimated population size of only about 100 individuals each. Therefore, it is crucial to expand our understanding of these subspecies to successfully conserve them. While their morphology, anatomy, ecology, pathology, and genetics are well studied, little is known about their physiology regulated in subspecies-specific manners. This study characterized their urinary volatile and nonvolatile organic compounds, with which individuals express their physiological status and territorial ownership. We found significantly higher levels of 3-mercapto-3-methyl-1-butanol and its structural analogs, which are scent signals of domestic cats, in the urinary headspace of Iriomote cats than in that of Tsushima leopard cats. There were no differences in the urinary levels of felinine, an amino acid that acts as a precursor of 3-mercapto-3-methyl-1-butanol, suggesting the variation of catalytic activities for decomposing felinine to 3-mercapto-3-methyl-1-butanol between subspecies. Both subspecies exhibited physiological proteinuria due to the secretion of carboxylesterase 5A, also known as cauxin, for the production of felinine. In conclusion, while the two endangered Japanese subspecies of mainland leopard cats share similar genetic backgrounds, urinary contents of metabolites vary between the subspecies. We suggest that after the separation into two subspecies, the regulation of the metabolic pathway for 3-mercapto-3-methyl-1-butanol production likely evolved differently in each subspecies in response to their specific environments.

A Floating Integrated Solar Micro‐Evaporator for Self‐Cleaning Desalination and Organic Degradation

AbstractSafe and clean freshwater harvesting from (organic‐containing) saline or wastewater holds great potential for mitigating water scarcity and pollution, but remains challenging. Herein, a floating photothermal/catalytic‐integrated interfacial micro‐evaporator (g‐C3N4@PANI/PS) is reported as a proof‐of‐concept multifunctional scavenger evaporator system (MSES) to achieve both solar‐driven complete desalination and organic degradation. The spherical porous lightweight polystyrene core, incorporated with a black surface functional layer (g‐C3N4@PANI), enables the hybrid micro‐evaporator to naturally float and thereby collectively self‐assemble under surface tension for interfacial evaporation, which achieves preeminent self‐cleaning for complete salt/solute separation and efficient organic photodegradation under rotation. Remarkably, the floating micro‐evaporator achieves a high solar‐vapor conversion efficiency of ≈90% with high interfacial energy localization and provides abundant active photocatalytic sites on the interface, which is further enhanced by interfacial photothermal cooperation. High photo‐driven degradation efficiencies of 99% for nonvolatile organic compounds (non‐VOC) bisphenol A and 95% for VOC phenol in wastewater are achieved. An outdoor comprehensive solar water treatment test toward organic‐containing high‐salinity sewage verifies the feasibility of MSES for sustainable freshwater harvesting (1.3 kg m−2 h−1), downstream salt recovery, and organic degradation. This strategy may inspire an integrated solution of water scarcity, clean energy, and environmental pollution toward carbon neutrality.

Possible mechanisms of action of Bacillus wiedmannii AzBw1, a biocontrol agent of the root-knot nematode, Meloidogyne arenaria

BackgroundWith increased environmental concerns and restrictions of chemical control, the importance of other eco-friendly strategies for management of the nematodes is being substantially grown nowadays. One of the most well-known strategies that have attracted the attentions is biological control of these deleterious agents. In our previous study (Moslehi et al. in Egypt J Biol Pest Control 31:1–11, 2021), Bacillus wiedmannii AzBw1 was introduced as a robust antagonistic agent against root-knot nematode Meloidogyne arenaria. Present study addressed the possible mechanisms of action of this strain.ResultsBased on quantitative bioassays it was shown that the strain AzBw1 is able to produce considerable amount of siderophore, protease, and chitinase. In an in vitro assay conducted by bi-plate Petri dishes, it was shown that hatching of the nematode eggs, subjected to bacterial volatile compounds (BVCs) was 34% lower than those of mock-treated control eggs. On the other hand, mortality of BVC-treated juveniles was 33.5% higher than those of mock-treated control juveniles. The secretory proteins from the medium culture of strain AzBw1 were precipitated and fractionated by anion exchange chromatography (AEC). Fractions from AEC were checked for hydrolytic activity and nematicidal effect. It was found that the fractions with the highest protease activity have a strong nematicidal effect. In contrast, significant nematicidal effect in the fraction with Chitinase activity was detected.ConclusionThe results suggested that protease activity played a key role in strain AzBw1 antagonism against root-knot nematode, M. arenaria. Finally, nonvolatile organic compounds were also extracted from the medium culture after removing secretory proteins and enzymes. Obtained results showed that these metabolites had also a strong anti-nematode effect.