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Fluorescent RNAs (FRs) provide an attractive approach to visualizing RNAs in live cells. Although the color palette of FRs has been greatly expanded recently, a green FR with high cellular brightness and photostability is still highly desired. Here we develop a fluorogenic RNA aptamer, termed Okra, that can bind and activate the fluorophore ligand ACE to emit bright green fluorescence. Okra has an order of magnitude enhanced cellular brightness than currently available green FRs, allowing the robust imaging of messenger RNA in both live bacterial and mammalian cells. We further demonstrate the usefulness of Okra for time-resolved measurements of ACTB mRNA trafficking to stress granules, as well as live-cell dual-color superresolution imaging of RNA in combination with Pepper620, revealing nonuniform and distinct distributions of different RNAs throughout the granules. The favorable properties of Okra make it a versatile tool for the study of RNA dynamics and subcellular localization.
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Laryngeal squamous cell carcinoma (LSCC) with a high incidence and mortality rate, has a serious impact worldwide. Phosphofructokinase-1 liver type (PFKL) is a major enzyme in glycolysis progress, but its role in modulating tumorigenesis and cisplatin (DDP) chemosensitivity of LSCC was still unclear. The mRNA and protein levels of PFKL were detected by qRT-PCR and immunohistochemical assay. Cell Counting Kit-8 assay and flow cytometry were carried out to observe cell viability, as well as apoptosis and mitochondrial reactive oxygen species (mito-ROS). Extracellular acidification rate and lactate content were measured using extracellular flux analysis and lactate assay kit. Immunofluorescent staining was used to evaluate the expression of γ-H2AX foci. DNA damage was detected via single-cell gel electrophoresis. Western blotting was introduced to evaluate the protein level of PFKL, LDHA, γ-H2AX, cleaved PARP, H3K27ac, and H3K9ac. Mice xenograft model of LSCC was built for in vivo validation. The PFKL expression was significantly increased in LSCC and associated with poor survival of LSCC patients. Knockdown of PFKL in LSCC cells significantly inhibited cell viability, ECAR, lactate content, and LDHA expression, but promoted mito-ROS level. Furthermore, knockdown of PFKL enhanced response of LSCC cells to DDP by increasing DDP-induced apoptosis, promoting DDP-induced mito-ROS level, γ-H2AX foci, tail DNA, and the expression of γ-H2AX and cleaved PARP. However, the overexpression of PFKL in LSCC cells had opposite experimental results. Nude mice tumor formation experiment proved that downregulation of PFKL significantly enhanced response of cells to DDP, demonstrated by reduced tumor volume, weight and increased TUNEL-positive cells. Suppression of CBP/EP300-mediated PFKL transcription inhibited cell viability and glycolysis and promoted mito-ROS in LSCC. PFKL promotes cell viability and DNA damage repair in DDP-treated LSCC through regulation of glycolysis pathway.
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Antineoplásicos , Sobrevivência Celular , Cisplatino , Glicólise , Neoplasias Laríngeas , Camundongos Nus , Cisplatino/farmacologia , Glicólise/efeitos dos fármacos , Humanos , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/tratamento farmacológico , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/genética , Animais , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Fosfofrutoquinase-1/metabolismo , Fosfofrutoquinase-1/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/genética , Camundongos Endogâmicos BALB C , Dano ao DNA/efeitos dos fármacosRESUMO
The electrocatalytic conversion of polysulfides is crucial to lithium-sulfur batteries and mainly occurs at triple-phase interfaces (TPIs). However, the poor electrical conductivity of conventional transition metal oxides results in limited TPIs and inferior electrocatalytic performance. Herein, a TPI engineering approach comprising superior electrically conductive layered double perovskite PrBaCo2O5+δ (PBCO) is proposed as an electrocatalyst to boost the conversion of polysulfides. PBCO has superior electrical conductivity and enriched oxygen vacancies, effectively expanding the TPI to its entire surface. DFT calculation and in situ Raman spectroscopy manifest the electrocatalytic effect of PBCO, proving the critical role of enhanced electrical conductivity of this electrocatalyst. PBCO-based Li-S batteries exhibit an impressive reversible capacity of 612 mAh g-1 after 500 cycles at 1.0 C with a capacity fading rate of 0.067% per cycle. This work reveals the mechanism of the enriched TPI approach and provides novel insight into designing new catalysts for high-performance Li-S batteries.
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Few-atom metal clusters (FAMCs) exhibit superior performance in catalyzing complex molecular transformations due to their special spatial environments and electronic states, compared to single-atom catalysts (SACs). However, achieving the efficient and accurate synthesis of FAMCs while avoiding the formation of other species, such as nanoparticles and SACs, still remains challenges. Herein, we report a two-step strategy for synthesis of few-atom platinum (Pt) clusters by predeposition of zinc single-atom-glue (Zn1) on MgO nanosheets (Ptn-Zn1/MgO), where FAMCs can be obtained over a wide range of Pt contents (0.09 to 1.45â wt %). Zn atoms can act as Lewis acidic sites to allow electron transfer between Zn and Pt through bridging O atoms, which play a crucial role in the formation and stabilization of few-atom Pt clusters. Ptn-Zn1/MgO exhibited a high selectivity of 93 % for anti-Markovnikov alkene hydrosilylation. Moreover, an excellent activity with a turnover frequency of up to 1.6×104â h-1 can be achieved, exceeding most of the reported Pt SACs. Further theoretical studies revealed that the Pt atoms in Ptn-Zn1/MgO possess moderate steric hindrance, which enables high selectivity and activity for hydrosilylation. This work presents some guidelines for utilizing atomic-scale species to increase the synthesis efficiency and precision of FAMCs.
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OBJECTIVE: To investigate the applicability of carboxymethyl starch (CMS) as a carrier to prepare solid dispersions (SDs) of piperine (PIP) and 18ß-glycyrrhetinic acid (ß-GA) (PIP-CMS and ß-GA-CMS SDs) and to explore the influence of drug properties on carrier selection. SIGNIFICANCE: The low oral bioavailability of natural therapeutic molecules, including PIP and ß-GA, severely restricts their pharmaceutical applications. Moreover, CMS, a natural polymer, is rarely reported as a carrier for SDs. METHODS: PIP-CMS and ß-GA-CMS SDs were prepared using the solvent evaporation method. Differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM) were used for formulation characterization. Additionally, drug release characteristics were investigated. RESULTS: In vitro dissolution studies showed that the dissolutions of PIP-CMS and ß-GA-CMS SDs were 1.90-2.04 and 1.97-2.22 times higher than pure PIP and ß-GA, respectively, at a drug:polymer ratio of 1:6. DSC, XRPD, FT-IR, and SEM analyses confirmed the formation of SDs in their amorphous states. Significant improvements in Cmax and AUC0-24 h of PIP-CMS and ß-GA-CMS SDs (17.51 ± 8.15 µg/mL and 210.28 ± 117.13 µg·h/mL, respectively) and (32.17 ± 9.45 µg/mL and 165.36 ± 38.75 µg·h/mL, respectively) were observed in the pharmacokinetic study. Compared with weakly acidic ß-GA, loading weakly basic PIP seemed to have a profound effect on stability through intermolecular forces. CONCLUSIONS: Our findings showed CMS could be a promising carrier for SDs, and loading weakly basic drug may be more suitable, especially in binary SDs system.
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Excipientes , Polímeros , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Disponibilidade Biológica , Solubilidade , Excipientes/química , Varredura Diferencial de CalorimetriaRESUMO
OBJECTIVE: A healthy and stable microbiome has many beneficial effects on the host, while an unbalanced or disordered microbiome can lead to various skin diseases. Hyaluronic acid is widely used in the cosmetics and pharmaceutical industries; however, specific reports on its effect on the skin microflora of healthy people have not been published. This study aimed to determine the effect of sodium hyaluronate on the facial microflora of healthy individuals. METHODS: Face of 20 healthy female volunteers between 18 and 24 years was smeared with sodium hyaluronate solution once per day. Cotton swabs were used to retrieve samples on days 0, 14, and 28, and high-throughput sequencing of 16 S rRNA was used to determine the changes in bacterial community composition. RESULTS: Facial application of HA can reduce the abundance of pathogenic bacteria, such as Cutibacterium and S. aureus, and increase the colonization of beneficial bacteria. CONCLUSION: This is the first intuitive report to demonstrate the effect of hyaluronic acid on facial microflora in healthy people. Accordingly, sodium hyaluronate was found to have a positive effect on facial skin health.
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Ácido Hialurônico , Microbiota , Feminino , Humanos , Bactérias , Ácido Hialurônico/farmacologia , RNA Ribossômico 16S/genética , Pele/microbiologia , Staphylococcus aureus , Adolescente , Adulto JovemRESUMO
The research on transportation of river microplastics (MPs) mainly focuses on the estimations of the total contents of river MPs entering the ocean, while the related transportation processes and influence factors were still largely unknown. In our study, the role of mangrove forest, a special tropical ecosystem in the estuary, on the transportations of MPs from rivers to ocean was explored. Except for the ND river with the absence of mangrove forest, the MPs collected from the water sample of the river upstream were much higher than their corresponding downstream (p < 0.05), with the interception rate of riverine MPs by mangrove forests ranging from 12.86% to 56% in dry season and 10.57%-42% in rainy season. The MPs with the characteristics of high density, larger size and regular shape were more easily intercepted. Furthermore, the combined effects of ecological indicators, the properties of mangrove and the hydrodynamic factors jointly determined the interception rates of MPs. This study provides a new perspective and data support for quantifying mangrove forests intercepting MPs in rivers as a factor of MPs retention in global rivers.
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Microplásticos , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Plásticos , Poluentes Químicos da Água/análise , Áreas AlagadasRESUMO
Microplastics (MPs) are becoming ubiquitous in environments and viewed as carriers of antibiotic resistance genes (ARGs). Rivers connecting differently urbanized areas contribute a significant input of MPs and ARGs to the environment. However, a systematic study assessing the role of urbanization in shaping antibiotic resistome and mobilome in riverine MPs is lacking. Here, we conducted a large-scale study by placing five types of MPs (polyethylene, polypropylene, polystyrene, polyethylene-fiber, and polyethylene-fiber-polyethylene) into Beilun River with an urbanization gradient. A total of 314 ARGs and 57 mobile genetic elements (MGEs) were detected in MPs by high-throughput quantitative polymerase chain reaction (PCR). The ARGs in MPs showed a clear spatial distribution with the abundance increased by 2 orders of magnitude from rural to urban regions. A holistic analysis of 13 socioeconomic and environmental factors identified that urbanization predominantly contributed to both the abundance and potential MGE-mediated dissemination of ARGs in riverine MPs. Notably, MPs types were found to significantly affect the resistome and dissemination risk of ARGs, with polypropylene being the preferred substrates to acquire and spread ARGs. This work highlights the necessity of controlling MPs and ARGs pollution in urban areas and provides an important guide for the future usage and disposal of plastics.
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Microplásticos , Rios , Antibacterianos , Genes Bacterianos , Plásticos , UrbanizaçãoRESUMO
Glioma is a leading cause of central nervous system malignant tumor-associated deaths in the world. However, the molecular mechanisms for glioma progression are still unclear, lacking effective therapeutic strategies. Gomisin J (GomJ) is a derivative of lignan compound, and shows regulatory effects on virus, oxidative stress and tumor progression. However, the role of GomJ in the meditation of glioma progression has not been explored. In this study, we found that GomJ markedly reduced the proliferation of glioma cell lines. Mitochondrial apoptosis was highly induced by GomJ, as evidenced by the significantly up-regulated expression of cytoplastic Cyto-c and cleaved Caspase-3. In addition, mitochondrial membrane potential (MMP) and oxidative stress were highly triggered in GomJ-incubated glioma cells, accompanied with the glycolysis suppression. Importantly, we found that GomJ could dramatically reduce the expression of hexokinase II (HKII) in glioma cells. At the same time, the dissociation of HKII from voltage-dependent anion channel (VDAC) in mitochondria was markedly induced by GomJ, contributing to glycolytic repression. The in vivo experiments confirmed that GomJ obviously reduced the growth of glioma with HKII reduction and few side effects. Taken together, these results demonstrated that GomJ could inhibit the proliferation, induce apoptosis and restrain HKII-regulated glycolysis during glioma progression. Herein, GomJ with few toxicity might be served as a potential therapeutic strategy for the treatment of glioma in humans.
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Antineoplásicos Fitogênicos/farmacologia , Glioma/tratamento farmacológico , Lignanas/farmacologia , Compostos Policíclicos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Progressão da Doença , Glioma/metabolismo , Glioma/patologia , Glicólise/efeitos dos fármacos , Hexoquinase/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Schisandra/química , Canais de Ânion Dependentes de Voltagem/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Fishery activities are an important source of microplastic pollution in coastal areas but have received little attention. The Beibu Gulf, a traditional fishing ground of China and the China-Indo Peninsula, was selected in this study, and the focus was on the impacts of fishery activities on the horizontal distribution of microplastics in sediment. The results showed that the dominant contaminants (polypropylene fibers and polyethylene fibers) might originate from the abrasion of fishing gear and contributed to 61.6% of the total abundance of microplastics in surface sediment. The abundance of polypropylene fibers and polyethylene fibers exhibited a strong correlation (R2 = 0.8586, p = 0.015) with values of fishery yields of different districts, which highlighted the effects of different fishery activities on microplastic contamination in marine sediment. Microplastics could be "hidden" in deep sediment to a depth of 60 cm. The estimated storage of microplastics in deep sediment (185 tons) was 5 times that in surface sediment. The assessment of microplastic storage worldwide might be underestimated because most previous studies only examined surface sediment. The abundance distribution and size distribution of microplastics in the sediment core suggested long-term burial of microplastics in deep sediment. Bioturbation might be responsible for the vertical transport of microplastics, leading to "fresh microplastics" preservation in "old sediment".
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Plásticos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Pesqueiros , MicroplásticosRESUMO
Microplastics sorption of persistent organic pollutants (POPs) was the core processes that cause negative effects to biota, and their influencing factors and related mechanisms are poorly understood. In this study, we explored the impacts of water extractable organic matter (WEOM), an important source of endogenous dissolved organic matter in mangrove sediment, on the sorption coefficients of typical parent, alkyl and N/O/S-containing polycyclic aromatic hydrocarbons (PAHs) by microplastics. The presence of L-WEOM (D) impeded the PAHs sorption as the coefficients (Kf) decreased to 10.17â¯(µg/kg)/(µg/L)n and to 8.39â¯(µg/kg)/(µg/L)n for fluorene (Flu) and 1-methyl-fluorene (1-M-Flu), respectively. The Kf exhibited good linear relationships with the aliphaticity of L-WEOM (pâ¯<â¯0.05) rather than the aromatic carbon/alkyl carbon content (pâ¯>â¯0.05). Under the presences of L-WEOM (D), (S) and (K), the lone pair electrons of N/O/S-containing PAHs was the dominant factor contributing to the obvious difference of the Kf values from the other groups. Moreover, the largest impact of L-WEOM (D) on the Flu sorption was in the case of PVC microplastics, while almost no effect was in the case of PS microplastics. The findings of our work may be helpful in improving our understanding of the role of WEOM on the sorption of PAHs to microplastics in the field mangrove sediment.
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Sedimentos Geológicos/química , Plásticos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Poluentes Químicos da Água/química , Adsorção , Hidrocarbonetos Policíclicos Aromáticos/análise , Água/química , Poluentes Químicos da Água/análise , Poluição da Água , Áreas AlagadasRESUMO
A laboratory experiment was conducted to evaluate the effects of flooding and aging on the phytoremediation of naphthalene (Nap), anthracene (Ant) and benzo[a]pyrene (B[a]P) in mangrove sediment by Kandelia obovata (K. obovata) Druce seedlings. Flooding increased dissipation efficiency in the rhizosphere zone from 69.47% to 82.45%, 64.27% to 80.41%, and 61.55% to 78.31% for Nap, Ant and B[a]P, respectively. Aging decreased dissipation efficiency significantly. Further investigation demonstrated that increased enzyme activity was one of important factors for increasing PAHs dissipation rates in flooded mangrove sediments. Moreover, a novel method for in situ quantitative investigation of PAHs distribution in root tissues was established using microscopic fluorescence spectra analysis. Subsequently, the effects of flooding and aging on the distribution of PAHs in root tissues were evaluated using this established method. The order of bioavailable fractions of PAHs after phytoremediation was as follows: non-aging/non-flooding>flooding>aging.
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Inundações , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Rhizophoraceae/efeitos dos fármacos , Áreas Alagadas , Antracenos/análise , Benzo(a)pireno/análise , Biodegradação Ambiental , China , Naftalenos/análise , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Rhizophoraceae/crescimento & desenvolvimento , Rizosfera , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Fatores de TempoRESUMO
Ecological retanning agent is an effective way to solve the pollution source of leather manufacturing industry. In this study, the gelatin from chrome-containing leather shavings in the leather industry was used to realize sustainable leather post-tanning. The gelatin hydrolysate (GH) coordinated with Zr4+ or Al3+ to prepare eco-friendly retanning agents GH-Zr and GH-Al. The successful coordination between GH and metal ions was characterized by FTIR and XPS. The retanning agents were characterized by FTIR curve-fitting and circular dichroism spectroscopy. The results showed that the conformation of the secondary structure of the polypeptide became ordered and stable after coordinating with the metal ions. The particle size and weight average molecular weight of the retanning agents were ~1700 nm and ~2100, respectively, measured by nanoparticle size analyzer and gel permeation chromatography (GPC). The retanning agents were applied to retanning of chrome tanned leather and glutaraldehyde tanned leather. The abundant free amino from retanning agents can consume the free formaldehyde. Meanwhile, retanning agents can effectively improve the multiple binding sites, resulting in favorable thickening rate (>110 %) and excellent dye and fatliquor absorption rate with ~99.91 % and ~93.18 %. Thus, this strategy can provide a viable choice for solid leather waste and sustainable development of the leather industry.
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Gelatina , Curtume , Alumínio/análise , Zircônio , Íons/análise , Resíduos Industriais/análiseRESUMO
The pervasive presence of nanoplastics (NPs) in environmental media has raised significant concerns regarding their implications for environmental safety and human health. However, owing to their tiny size and low level in the environment, there is still a lack of effective methods for measuring the amount of NPs. Leveraging the principles of Mie scattering, a novel approach for rapid in situ quantitative detection of small NPs in low concentrations in water has been developed. A limit of detection of 4.2 µg/L for in situ quantitative detection of polystyrene microspheres as small as 25 nm was achieved, and satisfactory recoveries and relative standard deviations were obtained. The results of three self-ground NPs showed that the method can quantitatively detect the concentration of NPs in a mixture of different particle sizes. The satisfactory recoveries (82.4% to 110.3%) of the self-ground NPs verified the good anti-interference ability of the method. The total concentrations of the NPs in the five brands of commercial bottled water were 0.07 to 0.39 µg/L, which were directly detected by the method. The proposed method presents a potential approach for conducting in situ and real-time environmental risk assessments of NPs on human and ecosystem health in actual water environments.
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Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Poliestirenos/química , Microplásticos/análise , Nanopartículas/química , Água Potável/análise , Água Potável/química , Microesferas , Tamanho da Partícula , Limite de Detecção , Espalhamento de RadiaçãoRESUMO
Microplastics (MPs) in aquatic environments provide a new ecological niche that facilitates the attachment of antibiotic-resistance genes (ARGs) and pathogens. However, the effect of particle size on the colonization of antibiotic resistomes and pathogens remains poorly understood. To address this knowledge gap, this study explored the antibiotic resistome and core microbiome on three distinct types of MPs including polyethylene, polypropylene, and polystyrene (PS), with varying sizes of 30, 200, and 3000 µm by metagenomic sequencing. Our finding showed that the ARG abundances of the PS type increased by 4-folds with increasing particle size from 30 to 3000 µm, and significant differences in ARG profiles were found across the three MP types. In addition, the concentrations of ARGs and mobile genetic elements (MGEs) were markedly higher in the MPs than in the surrounding water, indicating their enrichment at these artificial interfaces. Notably, several pathogens such as Pseudomonas aeruginosa, Mycobacterium tuberculosis, and Legionella pneumophila were enriched in MP biofilms, and the co-occurrence of ARGs and virulence factor genes (VFGs)/MGEs suggested the presence of pathogenic antibiotic-resistant microbes with potential mobility. Both redundancy analysis (RDA) and structural equation modeling (SEM) demonstrated that physicochemical properties such as zeta potential, MP size, and contact angle were the most significant contributors to the antibiotic resistome. Strikingly, no significant differences were observed in the health risk scores of the ARG profiles among different sizes and types of MPs. This study expands our knowledge on the impact of MP size on microbial risks, thus enhancing our understanding of the potential health hazards they pose.
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Microbiota , Microplásticos , Antibacterianos/farmacologia , Genes Bacterianos , Plásticos , Rios , Poliestirenos/química , Polipropilenos/químicaRESUMO
Myriad inherent and variable environmental features are controlling the assembly and succession of bacterial communities colonizing on mangrove microplastics (MPs). However, the mechanisms governing mangrove MPs-associated bacterial responses to environmental changes still remain unknown. Here, we assessed the dissimilarities of MPs-associated bacterial composition, diversity and functionality as well as quantified the niche variations of each taxon on plastispheres along river-mangrove-ocean and mangrove landward-to-seaward gradients in the Beibu Gulf, China, respectively. The bacterial richness and diversity as well as the niche breadth on mangrove sedimentary MPs dramatically decreased from landward to seaward regions. Characterizing the niche variations linked the difference of ecological drivers of MPs-associated bacterial populations and functions between river-mangrove-ocean (microplastic properties) and mangrove landward-to-seaward plastispheres (sediment physicochemical properties) to the trade-offs between selective stress exerted by inherent plastic substrates and microbial competitive stress imposed by environmental conditions. Notably, Rhodococcus erythropolis was predicted to be the generalist species and closely associated to biogeochemical cycles of mangrove plastispheres. Our work provides a reliable pathway for tackling the hidden mechanisms of environmental factors driving MPs-associated microbe from perspectives of niches and highlights the spatial dynamic variations of mangrove MPs-associated bacteria.
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Microplásticos , Áreas Alagadas , Plásticos , Bactérias , ChinaRESUMO
Mangrove leaves have been acknowledged as crucial sink for coastal microplastics (MPs). Whereas, the temporal dynamics of MPs intercepted by mangrove leaves have remained poorly understood. Here, we detected MPs intercepted by submerged and non-submerged mangrove leaves over time and the potential driving factors. Abundance and characteristics of MPs interception by mangrove leaves exhibited dynamic fluctuations, with the coefficient of variation (CV) of submerged mangrove leaves (CV = 0.604; 1.76 n/g to 15.45 n/g) being approximately twofold higher than non-submerged mangrove leaves (CV = 0.377; 0.74 n/g to 3.28 n/g). Partial least squares path model (PLS-PM) analysis further illustrated that MPs abundance on submerged mangrove leaves were negative correlated to hydrodynamic factors (i.e., current velocity and tidal range). Intriguingly, secreted salt as a significantly driver of MPs intercepted by mangrove leaves. Results of this work highlights that MPs intercepted by mangrove leaves is characterized by dynamic fluctuations and reveals the importance of hydrodynamic factors and secreted salt. Overall, this work identifies the pivotal buffering role played by mangrove leaves in intercepting MPs, which provides basic knowledge for better understanding of microplastic pollution status and control from mangrove plants.
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Microplásticos , Plásticos , Hidrodinâmica , Cloreto de Sódio , Transporte Biológico , NonoxinolRESUMO
The microbial composition and volatile components of fermented grains (FG) and pit mud (PM) are crucial for the quality and flavor of compound-flavor baijiu (CFB). The physicochemical indices, culturable microorganisms, microbial communities, and volatile components of FG and PM were analyzed and correlated in our research. Considering FG and PM, amplicon sequencing was used to analyze the microbial community and the volatile components were detected by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME). For FG, redundancy analysis and correlation perfume Circos were used to clarify the correlations between the dominant microbial community and volatile components. The results showed that Aspergillus, Pichia, and Rhizopus were the main fungal microflora in FG and PM, whereas Lactobacillus and Bacillus were the dominant bacteria in FG, and Methanosarcina and Clostridium sensu stricto 12 were the dominant bacteria in the PM. The microbial community and volatile compounds in the CB sampled from the bottom layers of the FG were greatly affected by those in the PM. There were 32 common volatile components in CB and PM. For FG, most of the volatile components were highly correlated with Lactobacillus, Bacillus, Aspergillus, Pichia, and Monascus, which includes alcohols, acids and esters. This study reveals correlations between microbial composition, volatile components, and the interplay of FG and PM, which are conducive to optimizing the fermentation process and improving the quality of CFB base.
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Pyrazines are important flavor components and healthy active components in Baijiu, which including tetramethylpyrazine (TTMP). During the brewing process, the traceability of microbial communities and the content distribution characteristics of TTMP are important for improving the quality and style characteristics of compound-flavored Baijiu (CFB). However, the traceability analysis of microorganisms in fermented grains (FG)-used in the production of CFB-lacks quantitative and systematic evaluation. In this study, the microbial communities and TTMP content of Jiuqu (JQ), Liangpei (LP), FG, and pit mud (CP) used in CFB production were characterized; further, coordinate and discriminant analyses were employed to determine differences in microbial communities. Additionally, traceability and correlation analyses were performed to reveal the origin of microbial communities in FG. The source, content, and distribution characteristics of TTMP based on the brewing process have also been discussed. The results showed that most of the bacterial and fungal communities at different levels of FG came from other sources, and the microorganisms of Cladosporium, Acetobacter, Aspergillus, Methanosarcina, and Bacillus were considered have a osculating correlations with TTMP content of FG. Taken together, this study provides insights into the origin of microbial communities in FG and the distribution characteristics of TTMP based on the CFB brewing process. The current findings are conducive for optimizing the fermentation process and improving the quality and style characteristics of CFB.
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Microplastics (MPs) are emerging as anthropogenic vectors to form plastisphere, facilitating microbiome colonization and pathogenic dissemination, thus contributing to environmental and health crises across various ecosystems. However, a knowledge gap persists regarding MPs risks and their driving factors in certain unique and vulnerable ecosystems, such as Karst travertine lakes, some of which are renowned World Natural Heritage Sites under ever-increasing tourism pressure. We hypothesized that tourism activities serve as the most important factor of MPs pollution, whereas intrinsic features, including travertine deposition can exacerbate potential environmental risks. Thus, metagenomic approaches were employed to investigate the geographical distribution of the microbiome, antibiotic resistance genes (ARGs), virulence factor genes (VFGs), and their combined environmental risks in Jiuzhaigou and Huanglong, two famous tourism destinations in Southwest China. The plastisphere risks were higher in Huanglong, contradicting our hypothesis that Jiuzhaigou would face more crucial antibiotic risks due to its higher tourist activities. Specifically, the levels of Lipopolysaccharide Lewis and fosD increased by sevenfold and 20-fold, respectively, from upstream to downstream in Huanglong, whereas in Jiuzhaigou, no significant accrual was observed. Structural equation modeling results showed that travertine deposition was the primary contributor to MPs risks in alpine karstic lakes. Our findings suggest that tourism has low impact on MPs risks, possibly because of proper management, and that travertine deposition might act as an MPs hotspot, emphasizing the importance of considering the unique aspects of travertine lakes in mitigating MPs pollution and promoting the sustainable development of World Natural Heritage Sites.