Pub Date : 2024-03-01DOI: 10.3389/fenvc.2024.1379862
Sebastian Fichter, Dominik Koll, Annabel Rolofs, Anton Wallner
Long-lived radionuclides in our environment provide important information on natural and anthropogenic processes. Their presence and concentration reflect the balance of production and decay. Geological archives store such information and the nuclides can be chemically extracted from the bulk sample. Accelerator mass spectrometry (AMS) represents a sensitive method to quantify those nuclides at natural levels. Three different terrestrial archives are discussed here as examples for radionuclide extraction using various chemical separation methods for subsequent AMS measurements. We focus on sample preparation for the cosmogenic radionuclides 10Be and 26Al, various anthropogenic actinide isotopes such as U, Pu, and Am as well as the astrophysically interesting nuclides 41Ca, 53Mn, and 60Fe. The processed materials cover samples with masses between a few mg and up to a few hundred kg and protocols are presented for the quantitative extraction of some 10,000 atoms of cosmogenic or interstellar origin per sample and even as low as a few hundred actinide atoms.
{"title":"Case studies of three geological archives for rare radionuclide measurements using accelerator mass spectrometry","authors":"Sebastian Fichter, Dominik Koll, Annabel Rolofs, Anton Wallner","doi":"10.3389/fenvc.2024.1379862","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1379862","url":null,"abstract":"Long-lived radionuclides in our environment provide important information on natural and anthropogenic processes. Their presence and concentration reflect the balance of production and decay. Geological archives store such information and the nuclides can be chemically extracted from the bulk sample. Accelerator mass spectrometry (AMS) represents a sensitive method to quantify those nuclides at natural levels. Three different terrestrial archives are discussed here as examples for radionuclide extraction using various chemical separation methods for subsequent AMS measurements. We focus on sample preparation for the cosmogenic radionuclides 10Be and 26Al, various anthropogenic actinide isotopes such as U, Pu, and Am as well as the astrophysically interesting nuclides 41Ca, 53Mn, and 60Fe. The processed materials cover samples with masses between a few mg and up to a few hundred kg and protocols are presented for the quantitative extraction of some 10,000 atoms of cosmogenic or interstellar origin per sample and even as low as a few hundred actinide atoms.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140092147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-26DOI: 10.3389/fenvc.2024.1332967
Mariem Fadhlaoui, Nolan J. T. Pearce, Isabelle Lavoie, Claude Fortin
Despite the growing prevalence of Bismuth (Bi), very little research has been carried to assess its potential toxic effects on aquatic organisms. This study aimed to address this gap by investigating the interactive effects of Bi exposure and elevated temperature on freshwater snails of the genus Lymnaea, specifically on their fatty acid (FA) profiles, oxidative stress markers (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST)) and lipid peroxidation (malondialdehyde (MDA) content). Bismuth exposure was introduced through two distinct routes: i) food via Bi-exposed biofilm (grown under 2 μM Bi), and ii) water (2 μM Bi). Exposed snails were maintained at two temperatures, 19°C and 25°C, over a duration of 14 days. Bismuth bioaccumulation occurred in Bi-exposed biofilm concurrently with a pronounced increase in polyunsaturated fatty acids (PUFA), likely as a protective mechanism to preserve cell structure and integrity. Bismuth bioaccumulation also occurred in snails with their FA composition largely reflecting the composition of their dietary source highlighting the direct link between diet and snail FA profiles. Additionally, the antioxidant enzymes studied exhibited diverse responses under Bi exposure and thermal stress, suggesting the induction of oxidative stress in snails. SOD activity increased at 25°C, suggesting a thermal stress. CAT activity remained high under all conditions, unaffected by temperature or Bi exposure. GPx levels increased in snails fed with Bi-laden biofilm, particularly at 19°C. GST activity showed great variability with a significant three-way interaction. The observed elevation in MDA levels among Bi-exposed snails suggested a potential deficiency in their antioxidant enzyme systems, leading to an increased susceptibility to lipid peroxidation. This research highlights the complex interaction between Bi contamination, temperature, and the physiological responses of aquatic organisms, and reveals the need for future research into the environmental impact of Bi in aquatic ecosystems. We further highlight the importance of food for Bi transfer to higher consumers and the importance of considering dietborne exposures in ecotoxicological studies.
尽管铋（Bi）越来越普遍，但很少有研究评估其对水生生物的潜在毒性影响。本研究旨在通过调查铋暴露和温度升高对淡水蜗牛属（Lymnaea）的交互影响，特别是对其脂肪酸（FA）概况、氧化应激标记（超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）、谷胱甘肽 S-转移酶（GST））和脂质过氧化（丙二醛（MDA）含量）的交互影响，来弥补这一空白。铋暴露通过两种不同的途径进行：i）通过铋暴露生物膜（在 2 μM Bi 下生长）的食物；ii）水（2 μM Bi）。暴露蜗牛在 19°C 和 25°C 两种温度下维持 14 天。在 Bi 暴露的生物膜中，铋的生物累积与多不饱和脂肪酸（PUFA）的明显增加同时发生，这可能是一种保护细胞结构和完整性的保护机制。铋在蜗牛体内也发生了生物累积，其脂肪酸组成在很大程度上反映了其食物来源的组成，这突出表明了食物与蜗牛脂肪酸组成之间的直接联系。此外，所研究的抗氧化酶在生物暴露和热应力下表现出不同的反应，表明蜗牛体内存在氧化应激。25°C 时 SOD 活性增加，表明存在热应力。CAT 活性在所有条件下都保持较高水平，不受温度或 Bi 暴露的影响。用含 Bi- 的生物膜喂养的蜗牛体内 GPx 含量增加，尤其是在 19°C 时。GST 活性的变化很大，三者之间存在显著的交互作用。在暴露于 Bi 的蜗牛中观察到的 MDA 水平升高表明，它们的抗氧化酶系统可能存在缺陷，从而导致对脂质过氧化反应的敏感性增加。这项研究强调了 Bi 污染、温度和水生生物生理反应之间复杂的相互作用，并揭示了未来研究 Bi 对水生生态系统环境影响的必要性。我们进一步强调了食物将 Bi 转移给高等消费者的重要性，以及在生态毒理学研究中考虑食物传播暴露的重要性。
{"title":"Interactive effects of bismuth exposure (water and diet) and temperature on snail fatty acid composition, antioxidant enzymes and lipid peroxidation","authors":"Mariem Fadhlaoui, Nolan J. T. Pearce, Isabelle Lavoie, Claude Fortin","doi":"10.3389/fenvc.2024.1332967","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1332967","url":null,"abstract":"Despite the growing prevalence of Bismuth (Bi), very little research has been carried to assess its potential toxic effects on aquatic organisms. This study aimed to address this gap by investigating the interactive effects of Bi exposure and elevated temperature on freshwater snails of the genus Lymnaea, specifically on their fatty acid (FA) profiles, oxidative stress markers (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST)) and lipid peroxidation (malondialdehyde (MDA) content). Bismuth exposure was introduced through two distinct routes: i) food via Bi-exposed biofilm (grown under 2 μM Bi), and ii) water (2 μM Bi). Exposed snails were maintained at two temperatures, 19°C and 25°C, over a duration of 14 days. Bismuth bioaccumulation occurred in Bi-exposed biofilm concurrently with a pronounced increase in polyunsaturated fatty acids (PUFA), likely as a protective mechanism to preserve cell structure and integrity. Bismuth bioaccumulation also occurred in snails with their FA composition largely reflecting the composition of their dietary source highlighting the direct link between diet and snail FA profiles. Additionally, the antioxidant enzymes studied exhibited diverse responses under Bi exposure and thermal stress, suggesting the induction of oxidative stress in snails. SOD activity increased at 25°C, suggesting a thermal stress. CAT activity remained high under all conditions, unaffected by temperature or Bi exposure. GPx levels increased in snails fed with Bi-laden biofilm, particularly at 19°C. GST activity showed great variability with a significant three-way interaction. The observed elevation in MDA levels among Bi-exposed snails suggested a potential deficiency in their antioxidant enzyme systems, leading to an increased susceptibility to lipid peroxidation. This research highlights the complex interaction between Bi contamination, temperature, and the physiological responses of aquatic organisms, and reveals the need for future research into the environmental impact of Bi in aquatic ecosystems. We further highlight the importance of food for Bi transfer to higher consumers and the importance of considering dietborne exposures in ecotoxicological studies.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140428843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-23DOI: 10.3389/fenvc.2024.1345484
Claude Fortin
Metal bioavailability in solution is mostly driven by two factors: complexation and competition. The first factor, complexation, contributes to decrease the overall reactivity of the metal by reducing the activity of the free metal ion, which is known as the common denominator of metal reactions involving either dissolved ligands or surface functional groups (abiotic or biotic). Ubiquitous in natural ecosystems, natural organic matter is, for several metals, the most important metal complexing ligand. The second factor, competition, contributes to decrease the availability of biotic ligands involved in the membrane transport of metals from the bulk solution to the intracellular medium. In freshwater systems, proton and hardness cation concentrations are the main parameters potentially modulating metal bioavailability. The above reflects the current accepted paradigm. In this paper, two knowledge gaps are identified: i) the role of natural organic matter other than metal complexation that may lead to an increase in metal bioavailability; and ii) the effects of multiple metals other than competition that may trigger biological feedback mechanisms which may, in turn, alter biotic ligand binding properties. More research efforts are needed to decipher the extent of these overlooked potential effects and to improve the predictability of metal bioavailability.
{"title":"Metal bioavailability in aquatic systems— beyond complexation and competition","authors":"Claude Fortin","doi":"10.3389/fenvc.2024.1345484","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1345484","url":null,"abstract":"Metal bioavailability in solution is mostly driven by two factors: complexation and competition. The first factor, complexation, contributes to decrease the overall reactivity of the metal by reducing the activity of the free metal ion, which is known as the common denominator of metal reactions involving either dissolved ligands or surface functional groups (abiotic or biotic). Ubiquitous in natural ecosystems, natural organic matter is, for several metals, the most important metal complexing ligand. The second factor, competition, contributes to decrease the availability of biotic ligands involved in the membrane transport of metals from the bulk solution to the intracellular medium. In freshwater systems, proton and hardness cation concentrations are the main parameters potentially modulating metal bioavailability. The above reflects the current accepted paradigm. In this paper, two knowledge gaps are identified: i) the role of natural organic matter other than metal complexation that may lead to an increase in metal bioavailability; and ii) the effects of multiple metals other than competition that may trigger biological feedback mechanisms which may, in turn, alter biotic ligand binding properties. More research efforts are needed to decipher the extent of these overlooked potential effects and to improve the predictability of metal bioavailability.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139957690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-16DOI: 10.3389/fenvc.2024.1342500
Louise Zilber, Edith Parlanti, Claude Fortin
Experimental design for the exposure of a green alga to lanthanum in the presence or absence of natural organic matter. Results show that accumulation and effects are greater than those expected based on the free ion concentration.
{"title":"Impact of organic matter of different origins on lanthanum speciation, bioavailability and toxicity toward a green alga","authors":"Louise Zilber, Edith Parlanti, Claude Fortin","doi":"10.3389/fenvc.2024.1342500","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1342500","url":null,"abstract":"Experimental design for the exposure of a green alga to lanthanum in the presence or absence of natural organic matter. Results show that accumulation and effects are greater than those expected based on the free ion concentration.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139962042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-15DOI: 10.3389/fenvc.2024.1329887
Vincent Noël, K. Boye, Hannah R. Naughton, E. Lacroix, Meret Aeppli, Naresh Kumar, S. Fendorf, Samuel M. Webb
Redox reactions underlie several biogeochemical processes and are typically spatiotemporally heterogeneous in soils and sediments. However, redox heterogeneity has yet to be incorporated into mainstream conceptualizations and modeling of soil biogeochemistry. Anoxic microsites, a defining feature of soil redox heterogeneity, are non-majority oxygen depleted zones in otherwise oxic environments. Neglecting to account for anoxic microsites can generate major uncertainties in quantitative assessments of greenhouse gas emissions, C sequestration, as well as nutrient and contaminant cycling at the ecosystem to global scales. However, only a few studies have observed/characterized anoxic microsites in undisturbed soils, primarily, because soil is opaque and microsites require µm-cm scale resolution over cm-m scales. Consequently, our current understanding of microsite characteristics does not support model parameterization. To resolve this knowledge gap, we demonstrate through this proof-of-concept study that X-ray fluorescence (XRF) 2D mapping can reliably detect, quantify, and provide basic redox characterization of anoxic microsites using solid phase “forensic” evidence. First, we tested and developed a systematic data processing approach to eliminate false positive redox microsites, i.e., artefacts, detected from synchrotron-based multiple-energy XRF 2D mapping of Fe (as a proxy of redox-sensitive elements) in Fe-“rich” sediment cores with artificially injected microsites. Then, spatial distribution of FeII and FeIII species from full, natural soil core slices (over cm-m lengths/widths) were mapped at 1–100 µm resolution. These investigations revealed direct evidence of anoxic microsites in predominantly oxic soils such as from an oak savanna and toeslope soil of a mountainous watershed, where anaerobicity would typically not be expected. We also revealed preferential spatial distribution of redox microsites inside aggregates from oak savanna soils. We anticipate that this approach will advance our understanding of soil biogeochemistry and help resolve “anomalous” occurrences of reduced products in nominally oxic soils.
{"title":"X-ray chemical imaging for assessing redox microsites within soils and sediments","authors":"Vincent Noël, K. Boye, Hannah R. Naughton, E. Lacroix, Meret Aeppli, Naresh Kumar, S. Fendorf, Samuel M. Webb","doi":"10.3389/fenvc.2024.1329887","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1329887","url":null,"abstract":"Redox reactions underlie several biogeochemical processes and are typically spatiotemporally heterogeneous in soils and sediments. However, redox heterogeneity has yet to be incorporated into mainstream conceptualizations and modeling of soil biogeochemistry. Anoxic microsites, a defining feature of soil redox heterogeneity, are non-majority oxygen depleted zones in otherwise oxic environments. Neglecting to account for anoxic microsites can generate major uncertainties in quantitative assessments of greenhouse gas emissions, C sequestration, as well as nutrient and contaminant cycling at the ecosystem to global scales. However, only a few studies have observed/characterized anoxic microsites in undisturbed soils, primarily, because soil is opaque and microsites require µm-cm scale resolution over cm-m scales. Consequently, our current understanding of microsite characteristics does not support model parameterization. To resolve this knowledge gap, we demonstrate through this proof-of-concept study that X-ray fluorescence (XRF) 2D mapping can reliably detect, quantify, and provide basic redox characterization of anoxic microsites using solid phase “forensic” evidence. First, we tested and developed a systematic data processing approach to eliminate false positive redox microsites, i.e., artefacts, detected from synchrotron-based multiple-energy XRF 2D mapping of Fe (as a proxy of redox-sensitive elements) in Fe-“rich” sediment cores with artificially injected microsites. Then, spatial distribution of FeII and FeIII species from full, natural soil core slices (over cm-m lengths/widths) were mapped at 1–100 µm resolution. These investigations revealed direct evidence of anoxic microsites in predominantly oxic soils such as from an oak savanna and toeslope soil of a mountainous watershed, where anaerobicity would typically not be expected. We also revealed preferential spatial distribution of redox microsites inside aggregates from oak savanna soils. We anticipate that this approach will advance our understanding of soil biogeochemistry and help resolve “anomalous” occurrences of reduced products in nominally oxic soils.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139836356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-15DOI: 10.3389/fenvc.2024.1329887
Vincent Noël, K. Boye, Hannah R. Naughton, E. Lacroix, Meret Aeppli, Naresh Kumar, S. Fendorf, Samuel M. Webb
Redox reactions underlie several biogeochemical processes and are typically spatiotemporally heterogeneous in soils and sediments. However, redox heterogeneity has yet to be incorporated into mainstream conceptualizations and modeling of soil biogeochemistry. Anoxic microsites, a defining feature of soil redox heterogeneity, are non-majority oxygen depleted zones in otherwise oxic environments. Neglecting to account for anoxic microsites can generate major uncertainties in quantitative assessments of greenhouse gas emissions, C sequestration, as well as nutrient and contaminant cycling at the ecosystem to global scales. However, only a few studies have observed/characterized anoxic microsites in undisturbed soils, primarily, because soil is opaque and microsites require µm-cm scale resolution over cm-m scales. Consequently, our current understanding of microsite characteristics does not support model parameterization. To resolve this knowledge gap, we demonstrate through this proof-of-concept study that X-ray fluorescence (XRF) 2D mapping can reliably detect, quantify, and provide basic redox characterization of anoxic microsites using solid phase “forensic” evidence. First, we tested and developed a systematic data processing approach to eliminate false positive redox microsites, i.e., artefacts, detected from synchrotron-based multiple-energy XRF 2D mapping of Fe (as a proxy of redox-sensitive elements) in Fe-“rich” sediment cores with artificially injected microsites. Then, spatial distribution of FeII and FeIII species from full, natural soil core slices (over cm-m lengths/widths) were mapped at 1–100 µm resolution. These investigations revealed direct evidence of anoxic microsites in predominantly oxic soils such as from an oak savanna and toeslope soil of a mountainous watershed, where anaerobicity would typically not be expected. We also revealed preferential spatial distribution of redox microsites inside aggregates from oak savanna soils. We anticipate that this approach will advance our understanding of soil biogeochemistry and help resolve “anomalous” occurrences of reduced products in nominally oxic soils.
{"title":"X-ray chemical imaging for assessing redox microsites within soils and sediments","authors":"Vincent Noël, K. Boye, Hannah R. Naughton, E. Lacroix, Meret Aeppli, Naresh Kumar, S. Fendorf, Samuel M. Webb","doi":"10.3389/fenvc.2024.1329887","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1329887","url":null,"abstract":"Redox reactions underlie several biogeochemical processes and are typically spatiotemporally heterogeneous in soils and sediments. However, redox heterogeneity has yet to be incorporated into mainstream conceptualizations and modeling of soil biogeochemistry. Anoxic microsites, a defining feature of soil redox heterogeneity, are non-majority oxygen depleted zones in otherwise oxic environments. Neglecting to account for anoxic microsites can generate major uncertainties in quantitative assessments of greenhouse gas emissions, C sequestration, as well as nutrient and contaminant cycling at the ecosystem to global scales. However, only a few studies have observed/characterized anoxic microsites in undisturbed soils, primarily, because soil is opaque and microsites require µm-cm scale resolution over cm-m scales. Consequently, our current understanding of microsite characteristics does not support model parameterization. To resolve this knowledge gap, we demonstrate through this proof-of-concept study that X-ray fluorescence (XRF) 2D mapping can reliably detect, quantify, and provide basic redox characterization of anoxic microsites using solid phase “forensic” evidence. First, we tested and developed a systematic data processing approach to eliminate false positive redox microsites, i.e., artefacts, detected from synchrotron-based multiple-energy XRF 2D mapping of Fe (as a proxy of redox-sensitive elements) in Fe-“rich” sediment cores with artificially injected microsites. Then, spatial distribution of FeII and FeIII species from full, natural soil core slices (over cm-m lengths/widths) were mapped at 1–100 µm resolution. These investigations revealed direct evidence of anoxic microsites in predominantly oxic soils such as from an oak savanna and toeslope soil of a mountainous watershed, where anaerobicity would typically not be expected. We also revealed preferential spatial distribution of redox microsites inside aggregates from oak savanna soils. We anticipate that this approach will advance our understanding of soil biogeochemistry and help resolve “anomalous” occurrences of reduced products in nominally oxic soils.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139776587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Quinolone antibiotics are a common class of antibiotics in the environment and have received considerable attention. In this study, three groups of mixed degradation strains targeting mixed quinolone antibiotics, norfloxacin (NOR), and enrofloxacin (ENR) were selected through screening, enrichment, and microbial diversity detection experiments. The strains screened in this study are divided into two categories through degradation efficiency experiments, community composition detection and functional enrichment analysis. In groups mix and ENR, the resistant bacteria are the main microorganisms and the degrading bacteria are the secondary ones, while in group NOR, the strains with degradation effects are the main ones, and the strains with resistance effects are the secondary ones. What’s more, that carbon sources have little effect on the community composition of the quinolone antibiotic degrading and tolerant bacteria, the difference between groups is mainly controlled by the type of antibiotics. On this basis, we found the key to NOR degradation is the cleavage of carbon nitrogen bonds on the piperazine ring, followed by oxygenation and deethylation. Preliminary studies have confirmed that the optimal degradation conditions for NOR degrading strains, and also found that environmental factors did not significantly affect the degradation efficiency of the Mix and NOR degrading strains, which indicating that the mixed bacteria can degrade NOR in different real environments effectively such as tap water, seawater, river water, and lake water. This manuscript is the first report on a mixed strain of quinolone antibiotic microbial degradation, and it is also the study with the highest NOR degradation efficiency among known reports. It has great research value for the co-metabolism and biodegradation of quinolone antibiotics in the environment.
喹诺酮类抗生素是环境中常见的一类抗生素，受到广泛关注。本研究通过筛选、富集和微生物多样性检测实验，筛选出三组针对混合喹诺酮类抗生素、诺氟沙星（NOR）和恩诺沙星（ENR）的混合降解菌株。通过降解效率实验、群落组成检测和功能富集分析，本研究筛选出的菌株分为两类。在混合组和 ENR 组中，抗性菌是主要微生物，降解菌是次要微生物；而在 NOR 组中，具有降解效果的菌株是主要菌株，具有抗性效果的菌株是次要菌株。此外，碳源对喹诺酮类抗生素降解菌和耐药菌的群落组成影响不大，组间差异主要受抗生素种类的控制。在此基础上，我们发现 NOR 降解的关键在于哌嗪环上碳氮键的裂解，然后是氧化和脱乙基。初步研究证实了NOR降解菌株的最佳降解条件，同时发现环境因素对混合菌株和NOR降解菌株的降解效率没有显著影响，这表明混合菌在自来水、海水、河水、湖水等不同的实际环境中都能有效降解NOR。本手稿是第一篇关于喹诺酮类抗生素微生物降解混合菌株的报道，也是目前已知报道中降解 NOR 效率最高的研究。它对喹诺酮类抗生素在环境中的共代谢和生物降解具有重要的研究价值。
{"title":"Study on the degradation and metabolic mechanism of four quinolone antibiotics by mixed strains","authors":"Hongdan Wang, Qiaoning Wang, Min Lv, Zhihua Song, Jialuo Yu, Xiaoyan Wang, Jinhua Li, Lingxin Chen","doi":"10.3389/fenvc.2024.1326206","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1326206","url":null,"abstract":"Quinolone antibiotics are a common class of antibiotics in the environment and have received considerable attention. In this study, three groups of mixed degradation strains targeting mixed quinolone antibiotics, norfloxacin (NOR), and enrofloxacin (ENR) were selected through screening, enrichment, and microbial diversity detection experiments. The strains screened in this study are divided into two categories through degradation efficiency experiments, community composition detection and functional enrichment analysis. In groups mix and ENR, the resistant bacteria are the main microorganisms and the degrading bacteria are the secondary ones, while in group NOR, the strains with degradation effects are the main ones, and the strains with resistance effects are the secondary ones. What’s more, that carbon sources have little effect on the community composition of the quinolone antibiotic degrading and tolerant bacteria, the difference between groups is mainly controlled by the type of antibiotics. On this basis, we found the key to NOR degradation is the cleavage of carbon nitrogen bonds on the piperazine ring, followed by oxygenation and deethylation. Preliminary studies have confirmed that the optimal degradation conditions for NOR degrading strains, and also found that environmental factors did not significantly affect the degradation efficiency of the Mix and NOR degrading strains, which indicating that the mixed bacteria can degrade NOR in different real environments effectively such as tap water, seawater, river water, and lake water. This manuscript is the first report on a mixed strain of quinolone antibiotic microbial degradation, and it is also the study with the highest NOR degradation efficiency among known reports. It has great research value for the co-metabolism and biodegradation of quinolone antibiotics in the environment.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139870475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Quinolone antibiotics are a common class of antibiotics in the environment and have received considerable attention. In this study, three groups of mixed degradation strains targeting mixed quinolone antibiotics, norfloxacin (NOR), and enrofloxacin (ENR) were selected through screening, enrichment, and microbial diversity detection experiments. The strains screened in this study are divided into two categories through degradation efficiency experiments, community composition detection and functional enrichment analysis. In groups mix and ENR, the resistant bacteria are the main microorganisms and the degrading bacteria are the secondary ones, while in group NOR, the strains with degradation effects are the main ones, and the strains with resistance effects are the secondary ones. What’s more, that carbon sources have little effect on the community composition of the quinolone antibiotic degrading and tolerant bacteria, the difference between groups is mainly controlled by the type of antibiotics. On this basis, we found the key to NOR degradation is the cleavage of carbon nitrogen bonds on the piperazine ring, followed by oxygenation and deethylation. Preliminary studies have confirmed that the optimal degradation conditions for NOR degrading strains, and also found that environmental factors did not significantly affect the degradation efficiency of the Mix and NOR degrading strains, which indicating that the mixed bacteria can degrade NOR in different real environments effectively such as tap water, seawater, river water, and lake water. This manuscript is the first report on a mixed strain of quinolone antibiotic microbial degradation, and it is also the study with the highest NOR degradation efficiency among known reports. It has great research value for the co-metabolism and biodegradation of quinolone antibiotics in the environment.
喹诺酮类抗生素是环境中常见的一类抗生素，受到广泛关注。本研究通过筛选、富集和微生物多样性检测实验，筛选出三组针对混合喹诺酮类抗生素、诺氟沙星（NOR）和恩诺沙星（ENR）的混合降解菌株。通过降解效率实验、群落组成检测和功能富集分析，本研究筛选出的菌株分为两类。在混合组和 ENR 组中，抗性菌是主要微生物，降解菌是次要微生物；而在 NOR 组中，具有降解效果的菌株是主要菌株，具有抗性效果的菌株是次要菌株。此外，碳源对喹诺酮类抗生素降解菌和耐药菌的群落组成影响不大，组间差异主要受抗生素种类的控制。在此基础上，我们发现 NOR 降解的关键在于哌嗪环上碳氮键的裂解，然后是氧化和脱乙基。初步研究证实了NOR降解菌株的最佳降解条件，同时发现环境因素对混合菌株和NOR降解菌株的降解效率没有显著影响，这表明混合菌在自来水、海水、河水、湖水等不同的实际环境中都能有效降解NOR。本手稿是第一篇关于喹诺酮类抗生素微生物降解混合菌株的报道，也是目前已知报道中降解 NOR 效率最高的研究。它对喹诺酮类抗生素在环境中的共代谢和生物降解具有重要的研究价值。
{"title":"Study on the degradation and metabolic mechanism of four quinolone antibiotics by mixed strains","authors":"Hongdan Wang, Qiaoning Wang, Min Lv, Zhihua Song, Jialuo Yu, Xiaoyan Wang, Jinhua Li, Lingxin Chen","doi":"10.3389/fenvc.2024.1326206","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1326206","url":null,"abstract":"Quinolone antibiotics are a common class of antibiotics in the environment and have received considerable attention. In this study, three groups of mixed degradation strains targeting mixed quinolone antibiotics, norfloxacin (NOR), and enrofloxacin (ENR) were selected through screening, enrichment, and microbial diversity detection experiments. The strains screened in this study are divided into two categories through degradation efficiency experiments, community composition detection and functional enrichment analysis. In groups mix and ENR, the resistant bacteria are the main microorganisms and the degrading bacteria are the secondary ones, while in group NOR, the strains with degradation effects are the main ones, and the strains with resistance effects are the secondary ones. What’s more, that carbon sources have little effect on the community composition of the quinolone antibiotic degrading and tolerant bacteria, the difference between groups is mainly controlled by the type of antibiotics. On this basis, we found the key to NOR degradation is the cleavage of carbon nitrogen bonds on the piperazine ring, followed by oxygenation and deethylation. Preliminary studies have confirmed that the optimal degradation conditions for NOR degrading strains, and also found that environmental factors did not significantly affect the degradation efficiency of the Mix and NOR degrading strains, which indicating that the mixed bacteria can degrade NOR in different real environments effectively such as tap water, seawater, river water, and lake water. This manuscript is the first report on a mixed strain of quinolone antibiotic microbial degradation, and it is also the study with the highest NOR degradation efficiency among known reports. It has great research value for the co-metabolism and biodegradation of quinolone antibiotics in the environment.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139810274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-23DOI: 10.3389/fenvc.2024.1339829
K. Medjoubi, K. Benzerara, J. Debrie, E. Tang, D. Bazin, E. Letavernier, K. Desjardins, A. Somogyi
Biomineralization is a widespread process among living organisms, playing a significant role in the formation and preservation of geological structures, biogeochemical cycles, regulation of ocean chemistry, and carbon sequestration. Moreover pathological biomineralization has a huge impact on human health. The growth of biominerals provides a rich area for research at multiple length-scales since they have controlled hierarchical structures from nano-to macroscopic scales. Here, we provide an overview on the potentials of the state-of-the-art scanning hard X-ray imaging and tomography methods developed at the NANOSCOPIUM beamline at Synchrotron Soleil in such studies. Multimodal scanning imaging provides simultaneous information on the elemental composition by X-ray fluorescence (XRF) spectrometry, on the sample morphology by absorption contrast imaging, on the crystalline structure by X-ray diffraction, and on the luminescence characteristics by X-ray Excited Optical Luminescence. As illustrated through diverse research cases about biomineralization in stromatolites and pathological calcification, such a versatile portfolio of X-ray imaging techniques provides unique complementary information to conventional laboratory techniques on biominerals and the underlying mineral precipitation processes.
生物矿化是生物体的一个普遍过程，在地质结构的形成和保存、生物地球化学循环、海洋化学调节和碳封存方面发挥着重要作用。此外，病理性生物矿化对人类健康也有巨大影响。生物矿物的生长为多长度尺度的研究提供了一个丰富的领域，因为它们具有从纳米到宏观尺度的可控分层结构。在此，我们概述了同步加速器 Soleil 的 NANOSCOPIUM 光束线开发的最先进的硬 X 射线扫描成像和层析成像方法在此类研究中的潜力。多模态扫描成像可同时提供 X 射线荧光 (XRF) 光谱法的元素组成信息、吸收对比成像的样品形态信息、X 射线衍射的晶体结构信息以及 X 射线激发光学发光的发光特性信息。正如有关叠层石中的生物矿化和病理钙化的各种研究案例所表明的那样，这种多功能的 X 射线成像技术组合为有关生物矿物和潜在矿物沉淀过程的传统实验室技术提供了独特的补充信息。
{"title":"State-of-the-art multimodal scanning hard X-ray imaging and tomography sheds light at multiple length-scales on biomineralization related processes","authors":"K. Medjoubi, K. Benzerara, J. Debrie, E. Tang, D. Bazin, E. Letavernier, K. Desjardins, A. Somogyi","doi":"10.3389/fenvc.2024.1339829","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1339829","url":null,"abstract":"Biomineralization is a widespread process among living organisms, playing a significant role in the formation and preservation of geological structures, biogeochemical cycles, regulation of ocean chemistry, and carbon sequestration. Moreover pathological biomineralization has a huge impact on human health. The growth of biominerals provides a rich area for research at multiple length-scales since they have controlled hierarchical structures from nano-to macroscopic scales. Here, we provide an overview on the potentials of the state-of-the-art scanning hard X-ray imaging and tomography methods developed at the NANOSCOPIUM beamline at Synchrotron Soleil in such studies. Multimodal scanning imaging provides simultaneous information on the elemental composition by X-ray fluorescence (XRF) spectrometry, on the sample morphology by absorption contrast imaging, on the crystalline structure by X-ray diffraction, and on the luminescence characteristics by X-ray Excited Optical Luminescence. As illustrated through diverse research cases about biomineralization in stromatolites and pathological calcification, such a versatile portfolio of X-ray imaging techniques provides unique complementary information to conventional laboratory techniques on biominerals and the underlying mineral precipitation processes.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139603248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-18DOI: 10.3389/fenvc.2024.1339628
Yongbao Zhang, Jianqing Du, Kang Xiao
The alpine area has become a sensitive indicator and amplifier of global climate change and human activities because of its unique geographical and climatic conditions. Being an essential part of biochemical cycling, dissolved organic matter (DOM) could effectively help understand the process, structure, and function of alpine aquatic ecosystems. Due to the low content and sampling difficulties, the analysis of DOM in alpine water demands high sensitivity with low sample volume, which has not been comprehensively reviewed. This review summarizes the DOM sampling, pretreatment, and analysis methods involving the characterization of concentration, spectroscopy, and molecular structure. Overall, conventional parameters are the basis of advanced characterization methods. Spectroscopic tests can reveal the optical properties of DOM in response to lights from ultraviolet to infrared wavelengths, to distinguish the chemical composition. Molecular structure characterizations can provide microscopic information such as functional groups, element ratios, and molecular weights. The combination of multiple methods can depict DOM composition from multiple perspectives. In sum, optimized sampling and pretreatment, high-sensitivity molecular characterization, and method integration are crucial for effectively analyzing DOM components in alpine waters. These perspectives help to standardize the DOM characterization process and to understand the correlation between DOM composition and its properties, as well as the migration and transformation of DOM.
高寒地区因其独特的地理和气候条件，已成为全球气候变化和人类活动的敏感指标和放大器。作为生化循环的重要组成部分，溶解有机物（DOM）可有效帮助了解高山水生生态系统的过程、结构和功能。由于溶解有机物含量低、取样困难，高山水体中的溶解有机物分析要求灵敏度高、取样量少，目前尚未对此进行全面综述。本综述总结了 DOM 的取样、预处理和分析方法，涉及浓度、光谱和分子结构的表征。总体而言，常规参数是先进表征方法的基础。光谱测试可揭示 DOM 在紫外线到红外线波长的光照下的光学特性，以区分化学成分。分子结构表征可提供微观信息，如官能团、元素比例和分子量。多种方法的结合可以从多个角度描述 DOM 的组成。总之，优化取样和预处理、高灵敏度分子表征以及方法整合对于有效分析高山水域中的 DOM 成分至关重要。这些方法有助于规范 DOM 表征过程，了解 DOM 成分与其特性之间的相关性，以及 DOM 的迁移和转化。
{"title":"Methods for molecular characterization of dissolved organic matter in the alpine water environment: an overview","authors":"Yongbao Zhang, Jianqing Du, Kang Xiao","doi":"10.3389/fenvc.2024.1339628","DOIUrl":"https://doi.org/10.3389/fenvc.2024.1339628","url":null,"abstract":"The alpine area has become a sensitive indicator and amplifier of global climate change and human activities because of its unique geographical and climatic conditions. Being an essential part of biochemical cycling, dissolved organic matter (DOM) could effectively help understand the process, structure, and function of alpine aquatic ecosystems. Due to the low content and sampling difficulties, the analysis of DOM in alpine water demands high sensitivity with low sample volume, which has not been comprehensively reviewed. This review summarizes the DOM sampling, pretreatment, and analysis methods involving the characterization of concentration, spectroscopy, and molecular structure. Overall, conventional parameters are the basis of advanced characterization methods. Spectroscopic tests can reveal the optical properties of DOM in response to lights from ultraviolet to infrared wavelengths, to distinguish the chemical composition. Molecular structure characterizations can provide microscopic information such as functional groups, element ratios, and molecular weights. The combination of multiple methods can depict DOM composition from multiple perspectives. In sum, optimized sampling and pretreatment, high-sensitivity molecular characterization, and method integration are crucial for effectively analyzing DOM components in alpine waters. These perspectives help to standardize the DOM characterization process and to understand the correlation between DOM composition and its properties, as well as the migration and transformation of DOM.","PeriodicalId":73082,"journal":{"name":"Frontiers in environmental chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139614335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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