The widespread existence of liquid crystal monomers (LCMs) in various environmental matrices has been demonstrated, yet studies on the toxicological effects of LCMs are considerably scarce and are urgently needed to be conducted to assess the adverse impacts on ecology and human health. Here, we conducted a bacteriological study on two representative human commensal bacteria, Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis), to investigate the effect of LCMs at human-relevant dosage and maximum environmental concentration on growth, metabolome, enzymatic activity, and mRNA expression. Microbial growth results exhibited that the highest inhibition ratio of LCMs on S. epidermidis reached 33.6% in our set concentration range, while the corresponding data on E. coli was only 14.3%. Additionally, LCMs showed more dose-dependent toxicity to S. epidermidis rather than E. coli. A novel in vivo solid-phase microextraction (SPME) fiber was applied to capture the in vivo metabolites of microorganisms. In vivo metabolomic analyses revealed that dysregulated fatty acid metabolism-related products of both bacteria accounted for >50% of the total number of differential substances, and the results also showed the species-specific and concentration-dependent metabolic dysregulation in LCM-exposed bacteria. The determination of enzymatic activity and mRNA relative expression levels related to oxidative stress confirmed our speculation that the adverse effects were related to the oxidative metabolism of fatty acids. This study complements the gaps in toxicity data for LCMs against bacteria and provides a new and important insight regarding metabolic dysregulation induced by environmental LCMs in human commensal bacteria.

In this study, a nitrogen-rich triazine-based porous polymer (NTP) was prepared by the Schiff base mechanism. The NTP contains a high nitrogen content (35.47%) with a larger BET surface area and an adsorption average pore diameter of 860 m(2) g(-1) and 3.92 nm, respectively. In addition, secondary amines (-C-NH-) and triazine nitrogen (-C=N-) in NTP provide a large number of nitrogen active sites, which facilitate the adsorption of triazole pesticides. The synthesized NTP was then used as the solid phase microextraction (SPME) extraction phase material to fabricate the NTP-SPME fiber, which had significantly higher performance in extracting tri-azole fungicides compared to the commercial fibers (p < 0.05). Subsequently, the bioaccumulation and elimination of three triazole fungicides (myclobutanil, propiconazole, and difenoconazole) in living vegetables were tracked by in vivo SPME sampling and quantified using a gas chromatography quadrupole time-of-flight mass spectrometry. The results showed that the concentrations of myclobutanil, propiconazole and difenoconazole were highest on the first day and showed a trend of first decreasing then equilibrium during bioaccumulation and gradually decreasing during elimination. The highest concentrations of myclobutanil, propiconazole, and difenoconazole in cabbage stems were 997.57 +/- 51.42, 841.20 +/- 21.42, and 56.82 +/- 1.30 ng/g, respectively. In addition, concentrations of difenoconazole were much lower than those of other pesticides throughout the experimental period, which may be related to the difficulty of uptake by cabbage roots due to its strong hydrophobicity and low solubility. This study highlights the application of NTP-SPME for tracking triazole fungicides in living Chinese cabbage plants, which provides valuable information to rationale use of triazole fungicides and their ecological risk assessment.

This study characterized the volatile aroma of bergamot by headspace solid-phase microextraction coupled with comprehensive two-dimensional chromatography quadrupole time-of-flight mass spectrometry The aroma-active compounds were also characterized using gas chromatography - olfactometry. A total of 323 volatile compounds and 29 aroma-active compounds were identified. Additionally, bergamot was shown to contain higher concentrations of alkenes (67), alcohols (63), esters (59), and ketones (36). Due to the higher peak capacity and separation resolution, comprehensive two-dimensional gas chromatography quadrupole time-of-flight mass spectrometry detected 218 more compounds than gas chromatography - mass spectrometry. The key characteristic volatiles of bergamot included alpha-terpineol, isobornyl formate, alpha-phellandrene dimer, furfural, and o-acetyltoluene. Volatile profiles may be a reference for subsequent work on the identification and quality appraisal of bergamot and its products.

Exposure to nano-polystyrene has the potential to increase the risk of Escherichia coli O157:H7 contamination in aquatic environments.

In mammals, the enzyme cGAS senses the presence of cytosolic DNA and synthesizes the cyclic dinucleotide (CDN) 2'3'-cGAMP, which triggers STING-dependent immunity. In Drosophila melanogaster, two cGAS-like receptors (cGLRs) produce 3'2'-cGAMP and 2'3'-cGAMP to activate STING. We explored CDN-mediated im-munity in 14 Drosophila species covering 50 million years of evolution and found that 2'3'-cGAMP and 3'2'-cGAMP failed to control infection by Drosophila C virus in D. serrata and two other species. We discov-ered diverse CDNs produced in a cGLR-dependent manner in response to viral infection in D. melanogaster, including 2'3'-c-di-GMP. This CDN was a more potent STING agonist than cGAMP in D. melanogaster and it also activated a strong antiviral transcriptional response in D. serrata. Our results shed light on the evolution of cGLRs in flies and provide a basis for understanding the function and regulation of this emerging family of pattern recognition receptors in animal innate immunity.

An in vivo solid-phase microextraction (SPME) fiber with high-coverage capture capacity of plant endogenous substances based on the porous covalent triazine framework (CTF) material was developed. The CTF fiber coupled with gas chromatographic quadrupole time-of-flight mass spectrometer (GC-QTOF-MS) analysis was used for monitoring untargeted endogenous metabolites in living Chinese cabbage plants (Brassica campestris L. ssp. chinensis Makino (var. communis Tsen et Lee)). A total of 100 endogenous substances were identified, mainly including aldehydes, ketones, acids, alcohols, phenols, alkanes, alkenes, esters, isorhodanates, nitriles, as well as indole and its derivatives. Using the in vivo metabolites analysis method, Chinese cabbage plants at different growing stages demonstrated significantly statistical differences in plant metabolism. In addition, metabolic dysregulation of Chinese cabbage plants under fipronil pesticide contamination was observed. To summarize, the proposed approach provides a feasible method to capture metabolic information in living vegetables and for risk assessment of pesticide use during agricultural production.

An in vivo solid-phase microextraction (SPME) fiber with high-coverage capture capacity of plant endogenous substances based on the porous covalent triazine framework (CTF) material was developed. The CTF fiber coupled with gas chromatographic quadrupole time-of-flight mass spectrometer (GC-QTOF-MS) analysis was used for monitoring untargeted endogenous metabolites in living Chinese cabbage plants (Brassica campestris L. ssp. chinensis Makino (var. communis Tsen et Lee)). A total of 100 endogenous substances were identified, mainly including aldehydes, ketones, acids, alcohols, phenols, alkanes, alkenes, esters, isorhodanates, nitriles, as well as indole and its derivatives. Using the in vivo metabolites analysis method, Chinese cabbage plants at different growing stages demonstrated significantly statistical differences in plant metabolism. In addition, metabolic dysregulation of Chinese cabbage plants under fipronil pesticide contamination was observed. To summarize, the proposed approach provides a feasible method to capture metabolic information in living vegetables and for risk assessment of pesticide use during agricultural production.

Hydrogen-bonded organic frameworks (HOFs) with multiple functions and permanent pores have received widespread attention due to their potential applications in gas adsorption/separation, drug delivery, photocatalysis, proton conduction, and other fields. Herein, we constructed a three-dimensional (3D) HOF with 1D square channels by utilizing a dual-functional tetrazolyl porphyrin ligand bearing an active center of the porphyrin core and open sites of nitrogen atoms through π-π stacking and hydrogen-bonding interaction self-assembly. The structure exhibits both solvent resistance and thermal stability, and especially, maintains these after being transformed into nanoparticles. Meanwhile, the active sites exposed on the inner wall of the pores can interact well with the photoactive cationic dye molecules to form an effective host-guest (H-G) system, which can realize boosted photosensitized singlet oxygen (1O2) production under red light irradiation and synergistic sterilization toward Staphylococcus aureus (S. aureus) with an inhibition ratio as high as 99.9%. This work provides a valuable design concept for HOF-related systems in pursuit of promoted photoactivity.

Abstract The volatile compounds in Rosa rugosa ‘Zi Zhi’, R. rugosa ‘Feng Hua’, and R. cv ‘Crimson Glory’ from three regions were determined by two-dimensional gas chromatography with quadrupole time-of-flight mass spectrometry coupled with knitting aromatic polymer – polydopamine (KAP@PDA) solid-phase microextraction. 82 compounds were identified by peak matching and retention indices, and R. cv ‘Crimson Glory’ contained the most volatile components. D-Limonene (up to 5131 μg kg−1), benzyl alcohol (up to 16,510 μg kg−1), benzeneacetaldehyde (up to 13,820 μg kg−1), phenylethyl alcohol (up to 49,020 μg kg−1) and citronellol (up to 7129 μg kg−1) were the major constituents in all R. rugosa species. In addition, benzaldehyde was highly abundant in R. cv ‘Crimson Glory’ (up to 23,130 μg kg−1). The primary volatile components responsible for the differences among the three R. rugosa cultivars and regions were distinguished by orthogonal partial least-squares discriminant analysis. The results suggested that phenylethyl alcohol contributed the most in distinguishing aroma quality for R. rugosa cultivars and those from different regions.

Two-dimensional gas chromatography (2D GC)-quadrupole time-of-flight mass spectrometry (QTOFMS) combined with derivatization was applied to determine naphthenic acids (NAs) in oil sand processed water (OSPW). Using the excellent resolution of 2D GC and mass resolution of QTOFMS with derivatization, 8 cyclohexane carboxylic acid isomers, 18 methylcyclohexyl carboxylic acid isomers, and 18 methylcyclohexyl acetic acid isomers were identified. Linear relationships across wide concentration ranges were established with correlation coefficients (R (2)) of 0.9995, 0.9992, and 0.9990, for cyclohexanecarboxylic acid, 4-methylcyclohexanecarboxylic acid, and 4-methylcyclohexane acetic acid. The precision, expressed as the relative standard deviation (RSD, n = 5), was from 7. 7-9.5% with recoveries between 72.0% and 84.9%. This method was applied to analyze sewage and showed high concentrations of naphthenic acids in untreated samples.

With a variety of pharmacological effects, the genus Elsholtzia and Mosla of Lamiaceae contain volatile components, including monoterpenes, sesquiterpenes, and their oxygenated derivatives that are widely used in traditional Chinese medicine (TCM). In this work, the volatile terpenes were studied by a more efficient technique based on headspace solid-phase micro-extraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography and quadrupole time-of-flight mass spectrometry (GC x GC-QTOFMS). A total of 91 terpenes consisting of 7 monoterpenes, 34 monoterpene oxides, 39 sesquiterpenes, and 11 sesquiterpene oxides were identified. From the retention time, 4,8,8-trimethyl-2-methylene-4-vinylbicyclo[5.2.0] nonane was identified to be the dominant volatile component in E. blanda, M. chinensis for the first time with 8% prevalence, but further verification is needed. 10 volatile terpenes, including 2-isopropyl-5-methyl-3- cyclohexen-1-one, isoegomaketone, alpha-muurolene, linalool oxide, ethyl2-(5-methyl- 5-vinyltetrahydrofuran-2-yl)propan-2-ylcarbonate, perilla ketone, elsholtzia ketone, alloaromadendrene oxide, artemisia ketone, longifolene-(V4) were identified by multivariate orthogonal partial least-squares discrimination analysis (OPLS-DA). Because these terpenes have significant pharmacological effects, such as anti-anxiety, anti-oxidation, anti-bacteria, and anti-virus properties, the identification of these terpenes may result in new information related to their pharmacological activities.

Emerging contaminants (ECs), especially antibiotics, have significantly polluted the environment and threaten the living circumstance of organisms. Environmental metabolomic has emerged to investigate the sublethal effects of ECs. However, lacking noninvasive and real-time sample pretreatment techniques restricts its development in environmental toxicology. Hence, in this study, a real-time and in vivo untargeted analytical technique towards microbial endogenous metabolites was developed via a novel composite solid-phase microextraction (SPME) fiber of ZIF-67 and polystyrene to realize the high-coverage capture of living gut microbial metabolites. To reveal the exposure risks of typical antibiotic - norfloxacin (NFX) to gut bacteria, four representative bacteria were exposed to NFX at environmentally relevant levels. Using the proposed SPME fiber, 70 metabolites were identified to obtain an apparent metabolic separation feature between control and NFX-treated (10 ng/mL) microbial groups, which revealed that the low environmental relevant concentration of NFX would affect normal metabolism of gut bacteria. Additionally, NFX exhibited species-specific toxic effects on microbial growth, especially Escherichia coli displaying a distinct dose-dependent trend. Antioxidative enzymatic activities results demonstrated that beneficial bacteria maintained the state of oxidative stress while symbiotic bacteria suffered from oxidative stress injury under NFX contamination, further corroborating its impact on human intestinal health. This study highlights the suitability of in vivo SPME in the field of metabolite extraction and simultaneously possesses a brilliant application foreground in the environmental metabolomics.

A rapid and sensitive method for analyzing trace β-blockers in complex biological samples, which involved magnetic solid-phase extraction (MSPE) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), was developed. Novel nanosilver-functionalized magnetic nanoparticles with an interlayer of poly(3,4-dihydroxyphenylalanine) (polyDOPA@Ag-MNPs) were synthesized and used as MSPE adsorbents to extract trace β-blockers from biological samples. After extraction, the analytes loaded on the polyDOPA@Ag-MNPs were desorbed using an organic solvent and analyzed by FTICR-MS. The method was rapid and sensitive, with a total detection procedure of less than 10 min as well as limits of detection and quantification in the ranges of 3.5-6.8 pg/mL and 11.7-22.8 pg/mL, respectively. The accuracy of the method was also desirable, with recoveries ranging from 80.9% to 91.0% following the detection of analytes in human blood samples. All the experimental results demonstrated that the developed MSPE-FTICR-MS method was suitable for the rapid and sensitive analysis of trace β-blockers in complex biological samples.

Overused antibiotics have severely polluted the environment and threaten the growth circumstance of gut bacteria by accumulating in human intestine through food chain. To reveal the exposure risks of antibiotics to gut bacteria, four representative gut bacteria were exposed to norfloxacin (NFX) at environmentally relevant levels. A real-time and in vivo untargeted analytical technique towards microbial metabolites was developed via a novel composite solid-phase microextraction (SPME) fiber of ZIF-67 and polystyrene to realize the high-coverage capture of living gut microbial metabolites. NFX exhibited species-specific toxic effects on microbial growth, especially Escherichia coli displaying a distinct dose-dependent trend. Using the proposed SPME fiber, 70 metabolites were identified to obtain an obvious metabolic separation feature between control and NFX-treated (10 ng/mL) microbial groups. In vivo metabolite profilling revealed that the low environmental relevant concentration of NFX would affect normal metabolism of gut bacteria. Antioxidative enzymatic activities results demonstrated that beneficial bacteria maintained the state of oxidative stress while symbiotic bacteria suffered from oxidative stress injury under NFX contamination, further corroborating its impact on human intestinal health. To conclude, this study highlights the application of in vivo SPME in providing new and important information regarding exogenous NFX contamination and related intestinal microbiome metabolism.

Incomplete separation and recycling of nanoparticles are causing undesirable nanopollution and thus raising great concerns with regard to nanosafety. Since microorganisms are important regulator of physiological processes in many organisms, the interaction between nanopollution and microbial metabolomics and the resultant impact on the host’s health are important but unclear. To investigate how typical nanopollution perturbs microbial growth and metabolism, Escherichia coli (E. coli) in vitro was treated with six water-dispersible nanomaterials (nanoplastic, nanosilver, nano-TiO2, nano-ZnO, semiconductor quantum dots (QDs), carbon dots (CDs)) at human-/environment-relevant concentration levels. The nanomaterials exhibited type-specific toxic effects on E. coli growth. Global metabolite profiling was used to characterize metabolic disruption patterns in the model microorganism exposed to different nanopollutants. The percentage of significant metabolites (p < 0.05, VIP > 1) accounted for 6%–38% of the total 293 identified metabolites in each of the nanomaterial-contaminated bacterial groups. Metabolic results also exhibited significant differences between different nanopollutants and dose levels, revealing type-specific and untypical concentration-dependent metabolic responses. Key metabolites responsive to nanopollution exposures were mainly involved in amino acid and purine metabolisms, where 5, 4, and 7 significant metabolic features were included in arginine and proline metabolism, phenylalanine metabolism, and purine metabolism, respectively. In conclusion, this study horizontally compared and demonstrated how typical nanopollution perturbs microbial growth and metabolomics in a type-specific manner, which broadens our understanding of the ecotoxicity of nanopollutants on microorganisms.

基于全二维气相色谱-四极杆飞行时间质谱法(GC×GC-QTOFMS)比较顶空-固相微萃取法(HS-SPME)和同时蒸馏法对砂仁中挥发性成分的提取效果.将样品四分法缩分、过筛后,分别用同时蒸馏法和HS-SPME(平衡温度设置为50℃,平衡、萃取时间分别设置为5,50 min)提取,用GC×GC-QTOFMS测定,用SIMCA 14.1和SPSS17.0软件进行主成分-判别分析(PCA-DA)和正交偏最小二乘法-判别分析(OPLS-DA),以确认两种方法的产地和批次鉴别能力以及区分两种方法的差异性成分.结果显示:HS-SPME和同时蒸馏法检出成分分别有162,178种,HS-SPME检出萜类化合物和烯烃类化合物含量明显高于同时蒸馏法的.检出的相对含量大于1.00％(以面积归一化法计算)的成分基本一致.PCA-DA结果显示,HS-SPME的产地和批次鉴别能力更强.OPLS-DA结果显示,可筛选出22种差异性成分用于区分两种方法,其中α-松油醇、α-没药醇和α-香柠檬醇为极显著差异性成分.

利用全二维气相色谱-四极杆飞行时间质谱(GC×GC-QTOF MS)建立了一种适用于独活挥发油化学成分的高通量检测方法,样品经水蒸气蒸馏提取后,直接采用全二维气相色谱进行分离,并根据谱库匹配、保留指数及精确质量数进行定性确认.结果表明,共分离鉴定了独活挥发油中207种化学成分,其中正向、反向匹配因子大于800的化合物占90％以上,分子离子峰的精确质量偏差均小于3 ppm,且80％以上物质的保留指数偏差在20以内.同时,通过半定量分析发现酯类、醇类、酚类、碳氢化合物是独活挥发油中最丰富的化学成分.研究结果对于挖掘独活挥发油的物质基础和药用价值具有重要意义.

文章采用顶空固相微萃取结合全二维气相色谱-四级杆飞行时间质谱联用的方法,建立一种适用于高通量检测青花椒挥发性香气成分的分析方法,并通过谱库匹配、保留指数及精确质量进行定性确认.结果表明,青花椒中共鉴定出75种挥发性香气化学成分,同时通过乙酸苯乙酯内标相对定量法对贵州、云南和四川不同地区的青花椒样品进行检测,发现青花椒中的主要挥发性香气物质为芳樟醇,其次是β-月桂烯、柠檬烯、β-罗勒烯等萜烯类物质,该方法为青花椒的品质分析和产地鉴别提供了方法参考.

基于全二维气相色谱-四级杆飞行时间质谱联用系统对同时蒸馏萃取砂仁挥发油成分进行高通量分离和精确质量检测.结果共鉴定到砂仁挥发油中83种化学成分,而常规一维只能检测到36种成分.通过对广东阳春、广西南宁和云南文山的砂仁挥发油成分进行分析和比较,发现α-檀香烯、β-檀香烯、β-杜松烯和β-石竹烯的含量差异较为明显,且广东阳春砂仁挥发油中的醇类和酚类物质较多,该方法为道地药材春砂仁的品质特征分析和产地鉴别提供了方法及数据参考.

Organic additives are extensively used as ingredients in biodegradable mulch films. They are swiftly released into the environment, which may have an ecotoxicological impact on plant growth and development, as well as on soil microbial community abundance and function. Herein, a method based on the application of microwave-assisted extraction (MAE) and dispersive liquid-liquid microextraction (DLLME) was developed to analyze eighty organic additives by gas chromatography-mass spectrometry in poly(butylene adipate terephthalate) (PBAT) biodegradable mulch films. This was a comprehensive study, including the identification of organic additives, optimization of MAE and DLLME methods, analysis of isocyanate conversion, and evaluation of the matrix effect (ME). Under the optimized experimental conditions, this method exhibited excellent detection capabilities for organic additives, except for 5 kinds of isocyanates and their reaction products, with coefficients of determination R-2 > 0.999 and lack of fit P > 0.05 in linear regression parameters. A negligible ME was observed. The relative recoveries were 93.0-109.8%, and the repeatability and reproducibility varied within the ranges of 2.06-8.76% and 2.38-10.23%, respectively. The limits of detection and limits of quantitation were 0.0008-0.0586 mu g g(-1) and 0.003-0.195 mu g g(-1), respectively. The developed method was further successfully applied to the analysis of organic additives in PBAT biodegradable mulch films from four different manufacturers. Interestingly, the Venn diagram and principal component analysis showed that different manufacturing origins display obvious characteristic differences in the organic additive types and concentrations.