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1.
Fitoterapia ; : 106000, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38729248

RESUMO

Five new characteristic cembrane-type diterpenoids (olibacartiols A-E, 1-5) were acquired from the gum resin of Boswellia carterii. The structures of these diterpenoids were characterized by detailed spectroscopic analysis, and compounds 1-3 were unambiguously confirmed by single-crystal X-ray diffraction experiments. The anti-inflammatory activities of the isolated compounds were evaluated using LPS-induced BV2 cell model and compounds 2-5 showed moderate NO inhibitory effects with IC50 values of 8.84 ±â€¯1.02, 9.82 ±â€¯1.95, 9.75 ±â€¯2.24, and 7.39 ±â€¯1.24 µM, respectively.

2.
Food Chem ; 450: 139317, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38636378

RESUMO

Microplastics (MPs) occurrence in marine ecosystems is well known, but their accumulation in seaweeds and subsequent human exposure remain understudied. This research quantifies MPs presence in two commonly consumed seaweeds, kelp (Saccharina japonica) and nori (Pyropia yezoensis), in East Asia, revealing widespread contamination dominated by microfibers (<500 µm). Based on dietary patterns, human uptake through seaweed consumption was estimated and quantified. Notably, Chinese people consume an estimated 17,034 MPs/person/year through seaweed consumption, representing 13.1% of their total annual MPs intake. This seaweeds-derived exposure surpasses all other dietary sources, contributing up to 45.5% of overall MPs intake. The highest intake was in South Korea, followed by North Korea, China, and Japan. This research identifies seaweeds as a major, previously overlooked route of dietary MPs exposure. These findings are crucial for comprehensive risk assessments of seaweed consumption and the development of mitigation strategies, particularly for populations in East Asian countries.

3.
Environ Sci Technol ; 58(17): 7270-7278, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38625742

RESUMO

Lead poisoning is globally concerning, yet limited testing hinders effective interventions in most countries. We aimed to create annual maps of county-specific blood lead levels in China from 1980 to 2040 using a machine learning model. Blood lead data from China were sourced from 1180 surveys published between 1980 and 2022. Additionally, regional statistical figures for 15 natural and socioeconomic variables were obtained or estimated as predictors. A machine learning model, using the random forest algorithm and 2973 generated samples, was created to predict county-specific blood lead levels in China from 1980 to 2040. Geometric mean blood lead levels in children (i.e., age 14 and under) decreased significantly from 104.4 µg/L in 1993 to an anticipated 40.3 µg/L by 2040. The number exceeding 100 µg/L declined dramatically, yet South Central China remains a hotspot. Lead exposure is similar among different groups, but overall adults and adolescents (i.e., age over 14), females, and rural residents exhibit slightly lower exposure compared to that of children, males, and urban residents, respectively. Our predictions indicated that despite the general reduction, one-fourth of Chinese counties rebounded during 2015-2020. This slower decline might be due to emerging lead sources like smelting and coal combustion; however, the primary factor driving the decline should be the reduction of a persistent source, legacy gasoline-derived lead. Our approach innovatively maps lead exposure without comprehensive surveys.


Assuntos
Chumbo , Aprendizado de Máquina , Chumbo/sangue , China , Humanos , Feminino , Masculino , Criança , Adolescente , Exposição Ambiental , Intoxicação por Chumbo/epidemiologia , Intoxicação por Chumbo/sangue
4.
Environ Pollut ; 351: 124042, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38679128

RESUMO

Chlorinated hydrocarbons (CHs) pose significant health risks due to their suspected carcinogenicity, necessitating urgent remediation efforts. While the combination of zero-valent iron (Fe0) and microbial action shows promise in mitigating CH contamination, field studies on this approach are scarce. We devised a novel three-layer permeable reactive barrier (PRB) material incorporating Fe0 and coconut shell biochar, effectively implemented at a typical CH-contaminated site. Field monitoring data revealed conducive conditions for reductive dechlorination of CHs, characterized by low oxygen levels and a relatively neutral pH in the groundwater. The engineered PRB material consistently released organic carbon and iron, fostering the proliferation of CH-dechlorinating bacteria. Over a 250-day operational period, the pilot-scale PRB demonstrated remarkable efficacy in CH removal, achieving removal efficiencies ranging from 21.9% to 99.6% for various CH compounds. Initially, CHs were predominantly eliminated through adsorption and iron-mediated reductive dechlorination. However, microbial reductive dechlorination emerged as the predominant mechanism for sustained and long-term CHs removal. These findings underscore the economic viability and effectiveness of our approach in treating CH-contaminated groundwater, offering promising prospects for broader application in environmental remediation efforts.

5.
Environ Pollut ; 351: 124056, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38677464

RESUMO

Reducing cadmium (Cd) content from contaminated farmland soils remains a major challenge due to the difficulty in separating commonly used adsorbents from soils. This study synthesized novel millimeter-sized magnetic Fe3O4/mercapto-functionalized attapulgite beads (MFBs) through a facile one-step gelation process incorporating alginate. The MFBs inherit the environmental stability of alginate and enhance its mechanical strength by hybridizing Fe3O4 and clay mineral components. MFBs can be easily separated from flooded soils by magnets. When applied to 12 Cd-polluted paddy soils and 14 Cd-polluted upland soils, MFBs achieved Cd(II) removal rates ranging from 16.9% to 62.2% and 9.8%-54.6%, respectively, within a 12-h period. The MFBs predominantly targeted the exchangeable and acid soluble, and reducible fractions of Cd, with significantly enhanced removal efficiencies in paddy soils compared to upland soils. Notably, MFBs exhibited superior adsorption performance in soils with lower pH and organic matter (OM) content, where the bioavailability and mobility of Cd are heightened. The reduction of Cd content by MFBs is a sustainable and safe method, as it permanently removes the bioavailable Cd from soil, rather than temporarily reducing its bioavailability. The functional groups such as -SH, -OH, present in attapulgite and alginate of MFBs, played a crucial role in Cd(II) adsorption. Additionally, attapulgite and zeolite provided a porous matrix structure that further enhanced Cd(II) adsorption. The results of X-ray photoelectron spectroscopy suggested that both chemical precipitation and surface complexation contributed to Cd(II) removal. The MFBs maintained 87.6% Cd removal efficiency after 5 regeneration cycles. The surface of the MFBs exposed new adsorption sites and increased the specific surface area during multiple cycles with Cd-contaminated soil. This suggests that MFBs treatment with magnetic retrieval is a potentially effective pathway for the rapid removal of Cd from contaminated farmland soils.

6.
Chemosphere ; 353: 141635, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447897

RESUMO

The performance of bacterial strains in executing degradative functions under the coexistence of heavy metals/heavy metal-like elements and organic contaminants is understudied. In this study, we isolated a fluorene-degrading bacterium, highly arsenic-resistant, designated as strain 2021, from contaminated soil at the abandoned site of an old coking plant. It was identified as a member of the genus Rhodococcus sp. strain 2021 exhibited efficient fluorene-degrading ability under optimal conditions of 400 mg/L fluorene, 30 °C, pH 7.0, and 250 mg/L trivalent arsenic. It was noted that the addition of arsenic could promote the growth of strain 2021 and improve the degradation of fluorene - a phenomenon that has not been described yet. The results further indicated that strain 2021 can oxidize As3+ to As5+; here, approximately 13.1% of As3+ was converted to As5+ after aerobic cultivation for 8 days at 30 °C. The addition of arsenic could greatly up-regulate the expression of arsR/A/B/C/D and pcaG/H gene clusters involved in arsenic resistance and aromatic hydrocarbon degradation; it also aided in maintaining the continuously high expression of cstA that codes for carbon starvation protein and prmA/B that codes for monooxygenase. These results suggest that strain 2021 holds great potential for the bioremediation of environments contaminated by a combination of arsenic and polycyclic aromatic hydrocarbons. This study provides new insights into the interactions among microbes, as well as inorganic and organic pollutants.


Assuntos
Arsênio , Hidrocarbonetos Policíclicos Aromáticos , Rhodococcus , Poluentes do Solo , Arsênio/metabolismo , Rhodococcus/genética , Rhodococcus/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Fluorenos/metabolismo , Biodegradação Ambiental , Poluentes do Solo/metabolismo , Microbiologia do Solo
7.
Science ; 383(6689): eadj4591, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38513023

RESUMO

Brassinosteroids are steroidal phytohormones that regulate plant development and physiology, including adaptation to environmental stresses. Brassinosteroids are synthesized in the cell interior but bind receptors at the cell surface, necessitating a yet to be identified export mechanism. Here, we show that a member of the ATP-binding cassette (ABC) transporter superfamily, ABCB19, functions as a brassinosteroid exporter. We present its structure in both the substrate-unbound and the brassinosteroid-bound states. Bioactive brassinosteroids are potent activators of ABCB19 ATP hydrolysis activity, and transport assays showed that ABCB19 transports brassinosteroids. In Arabidopsis thaliana, ABCB19 and its close homolog, ABCB1, positively regulate brassinosteroid responses. Our results uncover an elusive export mechanism for bioactive brassinosteroids that is tightly coordinated with brassinosteroid signaling.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Proteínas de Arabidopsis , Arabidopsis , Brassinosteroides , Trifosfato de Adenosina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Brassinosteroides/metabolismo , Ácidos Indolacéticos/metabolismo , Conformação Proteica
8.
Environ Sci Technol ; 58(14): 6258-6273, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38450439

RESUMO

Contamination of small-sized plastics is recognized as a factor of global change. Nanoplastics (NPs) can readily enter organisms and pose significant ecological risks. Arbuscular mycorrhizal (AM) fungi are the most ubiquitous and impactful plant symbiotic fungi, regulating essential ecological functions. Here, we first found that an AM fungus, Rhizophagus irregularis, increased lettuce shoot biomass by 25-100% when exposed to positively and negatively charged NPs vs control, although it did not increase that grown without NPs. The stress alleviation was attributed to the upregulation of gene expressions involving phytohormone signaling, cell wall metabolism, and oxidant scavenging. Using a root organ-fungus axenic growth system treated with fluorescence-labeled NPs, we subsequently revealed that the hyphae captured NPs and further delivered them to roots. NPs were observed at the hyphal cell walls, membranes, and spore walls. NPs mediated by the hyphae were localized at the root epidermis, cortex, and stele. Hyphal exudates aggregated positively charged NPs, thereby reducing their uptake due to NP aggregate formation (up to 5000 nm). This work demonstrates the critical roles of AM fungus in regulating NP behaviors and provides a potential strategy for NP risk mitigation in terrestrial ecosystems. Consequent NP-induced ecological impacts due to the affected AM fungi require further attention.


Assuntos
Micorrizas , Micorrizas/metabolismo , Microplásticos , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Hifas , Ecossistema , Expressão Gênica
9.
Pharm Dev Technol ; 29(3): 143-152, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38353125

RESUMO

OBJECTIVE: In order to improve the dissolution property of quercetin (QCT), the quercetin nanocrystals (QNCs) were prepared in this study. METHODS: QNCs were prepared by a 100 µm diameter Y-shape microfluidic channel. Some impact factors affecting the generation of QNCs such as concentration and flow rate were investigated. Furthermore, the fluid mixing in the microfluidic channel was simulated by fluid software. RESULTS: XRPD and DSC analyses indicated that the prepared QNCs were amorphous. Stable QNCs with a particle size of 77.9 ± 3.63 nm and polydispersity index of 0.26 ± 0.02 were obtained. TEM showed that the as-prepared QNCs had a uniform spherical shape with an average particle size of about 100-300 nm. In the dissolution medium without cosolvent Tween -80, the dissolution of QCT was poor, its final accumulated dissolution was only 3.95%, while that of QNCs was 66%. CONCLUSION: When QCT was changed to QNCs by microfluidic technology, its dissolution property could be obviously improved. Therefore, microfluidic technology as a new method to prepare nanocrystals has a good applying prospect in improving dissolution property for poorly water-soluble drugs.


Assuntos
Nanopartículas , Quercetina , Quercetina/química , Microfluídica , Polissorbatos , Água , Nanopartículas/química , Tamanho da Partícula , Solubilidade
10.
Adv Mater ; 36(18): e2311831, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38253422

RESUMO

Controlling the multi-state switching is significantly essential for the extensive utilization of 2D ferromagnet in magnetic racetrack memories, topological devices, and neuromorphic computing devices. The development of all-electric functional nanodevices with multi-state switching and a rapid reset remains challenging. Herein, to imitate the potentiation and depression process of biological synapses, a full-current strategy is unprecedently established by the controllable resistance-state switching originating from the spin configuration rearrangement by domain wall number modulation in Fe3GeTe2. In particular, a strong correlation is uncovered in the reduction of domain wall number with the corresponding resistance decreasing by in-situ Lorentz transmission electron microscopy. Interestingly, the magnetic state is reversed instantly to the multi-domain wall state under a single pulse current with a higher amplitude, attributed to the rapid thermal demagnetization by simulation. Based on the neuromorphic computing system with full-current-driven artificial Fe3GeTe2 synapses with multi-state switching, a high accuracy of ≈91% is achieved in the handwriting image recognition pattern. The results identify 2D ferromagnet as an intriguing candidate for future advanced neuromorphic spintronics.

11.
Glob Chang Biol ; 30(1): e17070, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273549

RESUMO

Tidal wetlands sequester vast amounts of organic carbon (OC) and enhance soil accretion. The conservation and restoration of these ecosystems is becoming increasingly geared toward "blue" carbon sequestration while obtaining additional benefits, such as buffering sea-level rise and enhancing biodiversity. However, the assessments of blue carbon sequestration focus primarily on bulk SOC inventories and often neglect OC fractions and their drivers; this limits our understanding of the mechanisms controlling OC storage and opportunities to enhance blue carbon sinks. Here, we determined mineral-associated and particulate organic matter (MAOM and POM, respectively) in 99 surface soils and 40 soil cores collected from Chinese mangrove and saltmarsh habitats across a broad range of climates and accretion rates and showed how previously unrecognized mechanisms of climate and mineral accretion regulated MAOM and POM accumulation in tidal wetlands. MAOM concentrations (8.0 ± 5.7 g C kg-1 ) (±standard deviation) were significantly higher than POM concentrations (4.2 ± 5.7 g C kg-1 ) across the different soil depths and habitats. MAOM contributed over 51.6 ± 24.9% and 78.9 ± 19.0% to OC in mangrove and saltmarsh soils, respectively; both exhibited lower autochthonous contributions but higher contributions from terrestrial or marine sources than POM, which was derived primarily from autochthonous sources. Increased input of plant-derived organic matter along the increased temperature and precipitation gradients significantly enriched the POM concentrations. In contrast, the MAOM concentrations depended on climate, which controlled the mineral reactivity and mineral-OC interactions, and on regional sedimentary processes that could redistribute the reactive minerals. Mineral accretion diluted the POM concentrations and potentially enhanced the MAOM concentrations depending on mineral composition and whether the mineral accretion benefited plant productivity. Therefore, management strategies should comprehensively consider regional climate while regulating sediment supply and mineral abundance with engineering solutions to tap the OC sink potential of tidal wetlands.


Assuntos
Ecossistema , Áreas Alagadas , Solo , Minerais , Sequestro de Carbono , Carbono
12.
Environ Sci Pollut Res Int ; 31(6): 9106-9120, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182955

RESUMO

Zhejiang Province is one of the top five major provinces producing traditional Chinese medicines (TCMs) and is famous for Zhebawei (in Chinese), the eight popular geo-authentic TCMs including Rhizoma Atractylodis Macrocephalae, Radix Paeoniae Alba, Thunberg Fritillary Bulb, Chrysanthemum morifolium, Corydalis yanhusuo W. T. Wang, Scrophulariae Radix, Ophiopogonis Radix, and Curcuma Wenyujin Y. H. Chen et C. Ling. High proportion application and residue of pesticides directly affect the quality and yield of TCMs. In this study, pesticides residual levels in crude and processing samples were assessed along with their health risks in Zhebawei primarily produced in Zhejiang Province. In total, the exceeded ratios of pesticides residual concentrations in above mentioned eight species were 15/23, 4/7, 26/70, 22/44, 10/19, 8/12, 7/15, and 0/2, respectively. No acute dietary intake health risks were found but the long-term risks from permethrin in S. Radix should be carefully considered, with all quotient values being higher than 2.1 for all groups between 7 and 70 years. Furthermore, the risks of total benzene hexachloride in T. Fritillary Bulb and carbendazim in C. morifolium should be closely monitored. Suggestions for the cultivation and pesticide management of herbal medicines have been proposed to promote the quality of medicinal materials.


Assuntos
Medicamentos de Ervas Chinesas , Praguicidas , Praguicidas/análise , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa , Rizoma/química , Raízes de Plantas
14.
Sci Total Environ ; 908: 168381, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37951266

RESUMO

Heavy metal (HM) contamination in soil necessitates effective methods to diagnose suspected contaminated areas and control rehabilitation processes. The synergistic use of proximal sensors demonstrates significant potential for rapid detection via accurate surveys of soil HM pollution at large scales and high sampling densities, and necessitates the selection of appropriate data mining and modeling methods for early diagnosis of soil pollution. The aim of this study is to evaluate the performance of a subarea model based on geographically partitioned and global models based on high-precision energy dispersive X-ray fluorescence (HD-XRF) and visible near-infrared (vis-NIR) spectra using a random forest model for predicting soil Cu and Pb concentrations. A total of 166 soil samples are acquired from a contaminated plot in Baiyin, Gansu Province, China. The soil samples are subjected to HM analysis and proximal sensor scanning in a laboratory. Vis-NIR spectral data are preprocessed using the Savitzky Golay (SG) and first-order derivative with Savitzky Golay (SGFD) methods. The results show that for predicting Cu and Pb concentrations in soil, the subarea models performs better than the global models in terms of quantitative prediction, based solely on individual HD-XRF data. For the subarea and global models, the R2 values are 0.961 and 0.981, respectively; the RMSE values are 27.8 and 79.6, respectively; and the RPD values are 4.96 and 7.38, respectively. However, making use of the random forest algorithm trained with data fusion obtained from the HD-XRF and vis-NIR sensors, the global model achieves the best predictions for Cu and Pb concentrations via HD-XRF + vis-NIR (SGFD) and HD-XRF + vis-NIR (SG), respectively. The results will provide a new perspective for modeling approaches to rapidly invert HM concentrations based on proximal sensor data fusion within a large scope of the study area.

15.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5719-5726, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-38114168

RESUMO

The medicinal Lindera aggregata(Lindera, Lauraceae) boasts abundant resources, which is widely used in clinical settings. It has been found that the main chemical constituents of this medicinal species are sesquiterpenoids, alkaloids, sesquiterpenoid dimers, flavonoids, and phenolic acids. Some unreported novel structures, including lindenane-type sesquiterpene dimers and trimers, have been discovered from L. aggregata in recent years. The extracts and active components of L. aggregata have anti-tumor, anti-inflammatory, antalgic, liver-protecting, antioxidant, lipid-lowering, and glucose-lowering activities, and their mechanisms of action have been comprehensively investigated. This study summarizes the research on the chemical constituents and bioactivities of L. aggregata over the past decade, which is expected to serve as a reference for the future research and utilization of L. aggregata.


Assuntos
Alcaloides , Lindera , Sesquiterpenos , Lindera/química , Flavonoides , Antioxidantes , Sesquiterpenos/química
16.
Environ Int ; 180: 108232, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37778288

RESUMO

Blue carbon ecosystems (BCEs), located at the land-sea interface, provide critical ecological services including the buffering of anthropogenic pollutants. Understanding the interactions between trace element (TE) loads in BCEs and socioeconomic development is imperative to informing management plans to address pollution issues. However, the identification of anthropogenic TE pollution in BCEs remains uncertain due to the complex geochemical and depositional processes and asynchronous socioeconomic development along continental coastlines. Here, priority-controlled TE (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) concentrations in the mangrove, saltmarsh and seagrass soils and plant tissues along the coastline of China were investigated while taking bare flat and upland soils as corresponding references. We demonstrate that blue carbon (BC) soils accumulated markedly higher concentrations of anthropogenic TEs than the reference soils, mainly due to the effective trapping of fine-grained particles and higher binding capacities. We identify the time course of TE changes over the last 100 years which shows increasing anthropogenic TE accumulation resulting from military activities (1930-1950) and the growth of industrial and agricultural activities (1950-1980), then reaching a maximum after national economic reform (1980-2000). Since the 2000s, decreases in TE discharges driven by socioeconomic reform and strengthened environmental regulations have led to a widespread reversal of anthropogenic TE concentrations in BC soils. Based on the current TE flux we estimate that BCEs can filter over 27.3-100 % of the TEs emitted in industrial wastewaters from Chinese coastal provinces annually. However, the uptake of these TEs by plants can be substantially reduced through various mechanisms offered by edaphic properties such as organic carbon, clay, and sulfur contents. Therefore, enhancing TE filtering while preventing TEs from entering food webs through the conservation and restoration of BCEs will greatly aid in achieving the sustainable development goal of the coastal zone under intensified anthropogenic activities.


Assuntos
Metais Pesados , Poluentes do Solo , Oligoelementos , Oligoelementos/análise , Ecossistema , Efeitos Antropogênicos , Monitoramento Ambiental/métodos , Solo/química , China , Metais Pesados/análise , Poluentes do Solo/análise
17.
ISME J ; 17(12): 2169-2181, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37775536

RESUMO

Nitrogen is a limiting nutrient for degraders function in hydrocarbon-contaminated environments. Biological nitrogen fixation by diazotrophs is a natural solution for supplying bioavailable nitrogen. Here, we determined whether the diazotroph Azotobacter chroococcum HN can provide nitrogen to the polycyclic aromatic hydrocarbon-degrading bacterium Paracoccus aminovorans HPD-2 and further explored the synergistic interactions that facilitate pyrene degradation in nitrogen-deprived environments. We found that A. chroococcum HN and P. aminovorans HPD-2 grew and degraded pyrene more quickly in co-culture than in monoculture. Surface-enhanced Raman spectroscopy combined with 15N stable isotope probing (SERS - 15N SIP) demonstrated that A. chroococcum HN provided nitrogen to P. aminovorans HPD-2. Metabolite analysis and feeding experiments confirmed that cross-feeding occurred between A. chroococcum HN and P. aminovorans HPD-2 during pyrene degradation. Transcriptomic and metabolomic analyses further revealed that co-culture significantly upregulated key pathways such as nitrogen fixation, aromatic compound degradation, protein export, and the TCA cycle in A. chroococcum HN and quorum sensing, aromatic compound degradation and ABC transporters in P. aminovorans HPD-2. Phenotypic and fluorescence in situ hybridization (FISH) assays demonstrated that A. chroococcum HN produced large amounts of biofilm and was located at the bottom of the biofilm in co-culture, whereas P. aminovorans HPD-2 attached to the surface layer and formed a bridge-like structure with A. chroococcum HN. This study demonstrates that distinct syntrophic interactions occur between A. chroococcum HN and P. aminovorans HPD-2 and provides support for their combined use in organic pollutant degradation in nitrogen-deprived environments.


Assuntos
Fixação de Nitrogênio , Nitrogênio , Nitrogênio/metabolismo , Hibridização in Situ Fluorescente , Pirenos
18.
Phytochemistry ; 215: 113866, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37739202

RESUMO

Lindenane sesquiterpenoid monomers and oligomers, characterized by a sterically congested cyclopentane and an unusual trans-5/6 ring junction, are mainly found in Chloranthaceae species and the genus Lindera Thunb (Lauraceae). Numerous studies have shown that lindenane sesquiterpenoid monomers and oligomers exhibit a broad range of biological activities, such as cytotoxicity, anti-inflammation, neuroprotection, antifungal, and anti-malarial activities. This review covers publications from the first identification of lindeneol in 1925-2023 and classifies the lindenane sesquiterpenoid derivatives into sesquiterpenoid monomers, sesquiterpenoid-monoterpene conjugates, sesquiterpenoid homodimers, sesquiterpenoid heterodimers, and trimeric sesquiterpenoids. In addition, their biological activities are summarized. This review will establish a scientific basis and provide guidance for utilizing this unique class of natural products as potential lead compounds to develop their application in treating diseases corresponding to inflammation, cancer, and plasmodium.


Assuntos
Antimaláricos , Produtos Biológicos , Magnoliopsida , Sesquiterpenos , Magnoliopsida/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Antimaláricos/farmacologia
19.
Nanomaterials (Basel) ; 13(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37764631

RESUMO

The cooperative transition of sulfur-containing pollutants of H2S/CO/H2 to the high-value chemical methyl mercaptan (CH3SH) is catalyzed by Mo-based catalysts and has good application prospects. Herein, a series of Al2O3-supported molybdenum carbide catalysts with K doping (denoted herein as K-Mo2C/Al2O3) are fabricated by the impregnation method, with the carbonization process occurring under different atmospheres and different temperatures between 400 and 600 °C. The CH4-K-Mo2C/Al2O3 catalyst carbonized by CH4/H2 at 500 °C displays unprecedented performance in the synthesis of CH3SH from CO/H2S/H2, with 66.1% selectivity and a 0.2990 g·gcat-1·h-1 formation rate of CH3SH at 325 °C. H2 temperature-programmed reduction, temperature-programmed desorption, X-ray diffraction and Raman and BET analyses reveal that the CH4-K-Mo2C/Al2O3 catalyst contains more Mo coordinatively unsaturated surface sites that are responsible for promoting the adsorption of reactants and the desorption of intermediate products, thereby improving the selectivity towards and production of CH3SH. This study systematically investigates the effects of catalyst carbonization and passivation conditions on catalyst activity, conclusively demonstrating that Mo2C-based catalyst systems can be highly selective for producing CH3SH from CO/H2S/H2.

20.
Toxics ; 11(7)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37505559

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are a class of compounds that persist in the environment globally. Besides being transported to the soil and sediments, which act as their sinks, PFASs can be transferred to several species of higher organisms directly or via bacteria, eliciting a wide range of adverse effects. Caenorhabditis elegans has been widely used in toxicological studies and life science research owing to its numerous advantages over traditional vertebrate models; notably, C. elegans has 65% conserved human-disease-associated genes and does not require ethical approvals for experimental use. This review covers a range of topics, from reported accumulation characteristics and lethal concentrations of PFAS in C. elegans to the mechanisms underlying the toxicity of PFAS at different levels, including reproductive, developmental, cellular, neurologic, oxidative, metabolic, immune, and endocrine toxicities. Additionally, the toxicity levels of some PFAS substitutes are summarized. Lastly, we discuss the toxicological mechanisms of these PFAS substitutes and the importance and promising potential of nematodes as in vivo models for life science research, epidemiological studies (obesity, aging, and Alzheimer's disease research), and toxicological investigations of PFASs and other emerging pollutants compared with other soil animals or model organisms.

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