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1.
Small ; 20(27): e2312091, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38308418

RESUMO

Grafted biopolymer binders are demonstrated to improve the processability and cycling stability of the silicon (Si) nanoparticle anodes. However, there is little systematical exploration regarding the relationship between grafting density and performance of grafted binder for Si anodes, especially when Si particles exceed the critical breaking size. Herein, a series of guar gum grafted polyacrylamide (GP) binders with different grafting densities are designed and prepared to determine the optimal grafting density for maximizing the electrochemical performance of Si submicroparticle (SiSMP) anodes. Among various GP binders, GP5 with recommended grafting density demonstrates the strongest adhesion strength, best mechanical properties, and highest intrinsic ionic conductivity. These characteristics enable the SiSMP electrodes to sustain the electrode integrity and accelerate lithium-ion transport kinetics during cycling, resulting in high capacity and stable cyclability. The superior role of GP5 binder in enabling robust structure and stable interface of SiSMP electrodes is revealed through the PeakForce atomic force microscopy and in situ differential electrochemical mass spectrometry. Furthermore, the stable cyclabilities of high-loading SiSMP@GP5 electrode with ultralow GP5 content (1 wt%) at high areal capacity as well as the good cyclability of Ah-level LiNi0.8Co0.1Mn0.1O2/SiSMP@GP5 pouch cell strongly confirms the practical viability of the GP5 binder.

2.
Small ; : e2401345, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767495

RESUMO

Novel binder designs are shown to be fruitful in improving the electrochemical performance of silicon (Si)-based anodes. However, issues with mechanical damage from dramatic volume change and poor lithium-ion (Li+) diffusion kinetics in Si-based materials still need to be addressed. Herein, an aqueous self-repairing borate-type binder (SBG) with a web-like architecture and high ionic conductivity is designed for Si and SiO electrodes. The 3D web-like architecture of the SBG binder enables uniform stress distribution, while its self-repairing ability promotes effective stress dissipation and mechanical damage repair, thereby enhancing the damage tolerance of the electrode. The tetracoordinate boron ions ( - BO 4 - $ - {\mathrm{BO}}_4^ - $ ) in the SBG binder boosts the Li transportation kinetics of Si-based electrodes. Based on dynamic covalent and ionic conductive boronic ester bonds, the diverse requirements of the binder, including uniform stress distribution, self-repairing ability, and high ionic conductivity, can be met by simple components. Consequently, the proposed straightforward multifunction design strategy for binders based on dynamic boron chemistry provides valuable insights into fabricating high-performance Si-based anodes.

3.
Small ; 19(2): e2205065, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36403220

RESUMO

Large-scale applications of conventional conductive binders for silicon (Si) anodes are challenging to accomplish due to their complex synthesis steps and high cost. Herein, a carbonized polymer dots-assisted polyvinyl alcohol-chitosan (PVA-CS-CPDs) binder is developed through a simple and low-cost hydrothermal method. Through rational design, the PVA-CS-CPDs binder retains rich polar groups while forming conjugated structures. The conjugated structure endows the PVA-CS-CPDs with high electronic conductivity, and the retained polar groups maintain strong binding strength. The proposed water-soluble binding system acts as both a binder and conductive additive, enabling stable cycling for high-Si-content (90 wt.%) anodes without any other conductive additives.

4.
Environ Sci Technol ; 57(33): 12302-12314, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37565790

RESUMO

Nanaerobes are a newly described class of microorganisms that use a unique cytochrome bd oxidase to achieve nanaerobic respiration at <2 µM dissolved oxygen (∼1% of atmospheric oxygen) but are not viable above this value due to the lack of other terminal oxidases. Although sharing an overlapping ecological niche with methanogenic archaea, the role of nanaerobes in methanogenic systems has not been studied so far. To explore their occurrence and significance, we re-analyzed published meta-omic datasets from animal rumina and waste-to-energy digesters, including conventional anaerobic digesters and anaerobic digesters with ultra-low oxygenation. Results show that animal rumina share broad similarities in the microbial community and system performance with oxygenated digesters, rather than with conventional anaerobic digesters, implying that trace levels of oxygen drive the efficient digestion in ruminants. The rumen system serves as an ideal model for the newly named nanaerobic digestion, as it relies on the synergistic co-occurrence of nanaerobes and methanogens for methane yield enhancement. The most abundant ruminal bacterial family Prevotellaceae contains many nanaerobes, which perform not only anaerobic fermentation but also nanaerobic respiration using cytochrome bd oxidase. These nanaerobes generally accompany hydrogenotrophic methanogens to constitute a thermodynamically and physiologically consistent framework for efficient methane generation. Our findings provide new insights into ruminal methane emissions and strategies to enhance methane generation from biomass.


Assuntos
Reatores Biológicos , Euryarchaeota , Animais , Anaerobiose , Reatores Biológicos/microbiologia , Bactérias , Metano , Oxirredutases , Esgotos/microbiologia , Citocromos , Digestão
5.
Environ Sci Technol ; 56(10): 6596-6607, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35476456

RESUMO

Biological models describing anaerobic digestion (AD) of sewage sludge have been widely applied to test various control and operation strategies. Anaerobic digestion model 1 (ADM1) provides a generic platform that includes the main processes of AD, excluding homoacetogenesis and the microbial structure. Homoacetogenic bacteria have been identified as important competitors for hydrogen consumption and acetate production. Although recent advances in meta-omics techniques have improved our characterization of AD microbial communities, conventional models treat functional groups as homogeneous and overlook the physiology and behavior of microbial individuality, limiting insights into mechanisms governing process performance. A novel microbial individuality model (MIM) that integrates kinetics, energetics, and agent-based modeling to describe a microbiome's behavior as heterogenic populations, including homoacetogenesis, was developed. The MIM was validated with two datasets from previous studies through daily biogas production, methane content, compound concentrations, and microbial relative abundance changes. The MIM identified the emergence of Methanosaeta at low concentrations of acetate. Moreover, this simulation supports experimental studies confirming that the overlooked homoacetogenesis is an important hydrogen sink in AD. Validated MIMs are expected to provide insights into syntrophic and competitive interactions among microbiomes in AD systems while testing different operational parameters in a virtual environment. The MIM offers a methodological framework to other biological treatment systems and their microbial community dynamics.


Assuntos
Microbiota , Esgotos , Acetatos , Anaerobiose , Reatores Biológicos/microbiologia , Hidrogênio , Metano , Esgotos/química
6.
Cell Mol Neurobiol ; 41(2): 293-307, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32382851

RESUMO

The main pathological features of ischemic stroke include neuronal damage and blood-brain barrier (BBB) dysfunction. Previous studies have shown that Evans Blue, a dye used to probe BBB integrity, could enter the brain only during the pathological status of ischemic stroke, indicating the potential pathologically activated therapeutic use of this chemical to treat ischemic stroke. In this study, we have reported that Evans Blue could produce in vitro neuroprotective effects against iodoacetic acid (IAA)-induced hypoxia neuronal death in HT22 cells. We further found that P2X purinoreceptor 4 (P2X4R), a subtype of ATP-gated cation channel, was expressed in HT22 cells. Evans Blue could prevent IAA-induced increase of P2X4R mRNA and protein expression. Interestingly, shRNA of P2X4R could protect against IAA-induced activation of p38, and SB203580, a specific inhibitor of p38, could reverse IAA-induced neurotoxicity, indicating that p38 is a downstream signaling molecule of P2X4R. Molecular docking analysis further demonstrated the possible interaction between Evans Blue and the ATP binding site of P2X4R. Most importantly, pre-treatment of Evans Blue could largely reduce neurological and behavioral abnormity, and decrease brain infarct volume in middle cerebral artery occlusion/reperfusion (MCAO) rats. All these results strongly suggested that Evans Blue could exert neuroprotective effects via inhibiting the P2X4R/p38 pathway, possibly by acting on the ATP binding site of P2X4R, indicating that Evans Blue might be further developed as a pathologically activated therapeutic drug against ischemic stroke.


Assuntos
Azul Evans/farmacologia , Fármacos Neuroprotetores/farmacologia , Receptores Purinérgicos P2X4/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Infarto Encefálico/complicações , Infarto Encefálico/patologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/patologia , Ácido Iodoacético , Masculino , Camundongos , Modelos Biológicos , Simulação de Acoplamento Molecular , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
7.
Environ Sci Technol ; 53(9): 5111-5123, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30946574

RESUMO

In recent years, many life-cycle assessments (LCAs) have been applied to the field of sewage treatment (ST). However, most LCAs lack systematic data collection (DC) and processing methods for inventories of conventional ST (CST), much less for recently developed technologies. In addition, the use of site-generic databases results in LCAs that lack the representativeness and understanding of the regional environmental impacts and trade-offs between different impact categories, especially nutrient enrichment and toxicity-related categories. These shortcomings make comparative evaluation and implementation more challenging. In order to assist in the decision-making process, a novel stoichiometric life-cycle inventory (S-LCI) for ST was developed. In the S-LCI, biochemical pathways derived from elemental analyses combined with process-engineering calculations enable steady-state comparison of the water, air, and soil emissions of any sewage and sludge sample treated through the ST configurations analyzed herein. The DC required for the estimation of the foreground data for a CST is summarized in a 41-item checklist. Moreover, the S-LCI was validated for CST by comparing the S-LCI with actual ST plant operations performed in Hong Kong. A novel energy-derived ST inventory is developed and compared here with the CST. The resulting inventories are ready to be integrated into the SimaPro software for life cycle impact assessment as illustrated by the case study. Using the S-LCI not only helps to standardize the DC and processing, but it also enhances the level of specificity by using sample characterization and site-specific data. The EcoInvent database, which contains a single sample characterization per Swiss and global average ST plant class could be expanded by using the S-LCI.


Assuntos
Meio Ambiente , Esgotos , Hong Kong , Sensibilidade e Especificidade
8.
Appl Microbiol Biotechnol ; 103(4): 1953-1960, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30603848

RESUMO

Anaerobic ammonium oxidation (anammox) has been widely applied for biological nitrogen removal in freshwater systems, and there is a potential for its extension in saline water systems. In this study, the abundance and biodiversity of anammox bacteria were investigated in both saline and freshwater full-scale sewage treatment plants (STPs). The anammox bacteria were widely found in four tested STPs with abundance of 105-107 copies per mL of 16S rRNA gene. Phylogenetic results showed that Ca. Scalindua and Ca. Brocadia dominated in saline and freshwater STPs, respectively. Ca. Kuenenia dominated in one of freshwater STPs. However, redundancy discriminate analysis (RDA) indicates the distribution of Ca. Kuenenia in both saline and freshwater conditions. To further elucidate these observations, the Monod model was integrated with Gauss equation for the evaluation of salinity-induced kinetics. Model results reveal that when nitrite concentration (SNO2-) is higher than nitrite affinity constant (KNO2-), salinity (over ~ 3.0%) is responsible for Candidatus Scalindua dominance over Candidatus Kuenenia. Conversely, in nitrite-depleted conditions (KNO2- ≥ SNO2-), high nitrite affinity leads to the predominance of Ca. Scalindua in all salinities. This study provides fundamental insights into saline anammox applications.


Assuntos
Compostos de Amônio/metabolismo , Bactérias Anaeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/metabolismo , Salinidade , Microbiologia da Água , Água/química , Anaerobiose , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Oxirredução , Filogenia , Doenças das Plantas , Plantas , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
Appl Environ Microbiol ; 79(5): 1735-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23263956

RESUMO

We isolated a Bacillus sp. strain that could display broad-spectrum biofilm inhibition. The broad biofilm prevention could be achieved mainly by direct contact between inhibitor and target cells or was accompanied by an interaction with secreted inhibitory compounds. The repression of cell surface fimbria-like appendages of a biofilm producer was also observed; this was considered to contribute to the reduction in mixed biofilms.


Assuntos
Antibiose , Bacillus/fisiologia , Biofilmes/crescimento & desenvolvimento , Antibacterianos/metabolismo , Bacillus/metabolismo
10.
J Environ Biol ; 34(2 Spec No): 437-44, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24620615

RESUMO

Fixed film processes and activated sludge processes are two main families of wastewater treatment systems which all refer to the heterogeneous microbial communities. Meanwhile, biofilms in drinking water distribution systems (DWDS) and biofouling in membrane systems are significant problems in the water and wastewater treatment which reduce the microbial quality of drinking water and limit the development of membrane system respectively. Since biofilms and quorum sensing (QS) as two microbial social behaviors have been inextricably linked, a number of studies have focused on the role of QS signaling and QS inhibition in the processes of water and wastewater treatment, which will help us engineer these biological treatment processes successfully and develop promising approaches for control of microbial adhesion, colonization and biofilm formation. This review gives a summary of recent known QS mechanisms and their role in biofilm formation for different species. Particular attentions are dedicated to the signaling molecules involved in some microbial granulation processes and the potential applications by some of their natural and synthetic analogues in the treatment of membrane biofouling.


Assuntos
Bactérias/classificação , Fenômenos Fisiológicos Bacterianos , Biofilmes/crescimento & desenvolvimento , Percepção de Quorum , Eliminação de Resíduos Líquidos , Aerobiose , Microbiologia da Água
11.
ACS Appl Mater Interfaces ; 15(31): 37486-37496, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37492883

RESUMO

Developing sodium-ion batteries (SIBs) with high initial coulombic efficiency (ICE) and long-term cycling stability is crucial to meet energy storage device requirements. Designing anode materials that could exhibit high ICE is a promising strategy to realize enhanced energy density in SIBs. A trifunctional network binder substantially improves the electrochemical performance and ICE, providing excellent mechanical properties and strong adhesion strength. A rationally designed electrode material and binder can achieve high ICE, long cycling performance, and excellent specific capacity. Here, a NiS/NiS2 heterostructure as an anode material and a trifunctional network binder (SA-g-PAM) are designed for SIBs. Unprecedently, the anode comprising of an SA-g-PAM binder achieved the highest ICE of 90.7% and remarkable cycling stability for 19000 cycles at a current density of 10 A g-1 and maintained the specific capacity of 482.3 mAh g-1 even after 19000 cycles. This exciting work provides an alternate direction to the battery industry for developing high-performance electrode materials and binders with high ICE and excellent cycling stability for energy storage devices.

12.
J Colloid Interface Sci ; 652(Pt A): 971-978, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37634370

RESUMO

Silicon (Si) is considered a high-capacity anode material with potential for next-generation lithium-ion batteries. However, the commercial application of Si anode is seriously hindered by huge volume variation (>300%) and limited Li+ diffusion ability. Herein, lithium metasilicate (LS), a novel inorganic binder, was innovatively developed to accommodate these challenges. Favorable compatibility is observed between the LS binder and Si nanoparticles (SiNPs) due to the existence of Si element within the LS skeleton. The interaction of the LS binder and SiNPs leads to a strong adhesion effect, enhancing the cycling stability of Si anode. The Si electrode with the LS binder presented an average discharge capacity of 2123 mAh/g at 0.84 A/g after 100 cycles. Furthermore, the presence of the Li+ transport channel within the LS binder enhances Li+ diffusion ability within Si anode. As a result, the average discharge capacity reaches 663 mAh/g at 8.4 A/g. This work thus explored new inorganic binder design approaches for Si anode, contributing to the advancement of high-performance Si anode.

13.
Zoonoses Public Health ; 70(1): 93-102, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36315202

RESUMO

A cluster of Chlamydia psittaci (C. psittaci) cases was reported in Zhejiang Province, China, 2019. This study evaluates the extent of the outbreak and determines the source of infection. Real-time PCR and sequencing of the ompA gene of C. psittaci were performed to identify the cases, the domesticated poultry and close contacts. The index patient was a 76-year-old woman with chronic vertigo, and Case 2 was a 64-year-old female farmer with herpes zoster. Both women bought psittaci-infected chickens or ducks from the same mobile street vendor and raised them for 10 days and 23 days before fever onset. There were no direct contact between the two women. C. psittaci test was positive for the two patients, one sick chicken, three healthy ducks and the vendor's chicken cage. Phylogenetic analysis showed that all seven C. psittaci positive samples carried identical ompA genotype A of C. psittaci. Of all of the patients' 148 close contacts, none tested positive for C. psittaci, or developed acute respiratory symptoms. Both patients were discharged after a 4-week hospital stay. In conclusion, the source of this cluster was the poultry infected with C. psittaci, which occasionally cause infections in farmers, but inter-human transmission seems unlikely.


Assuntos
Chlamydophila psittaci , Doenças das Aves Domésticas , Psitacose , Humanos , Animais , Feminino , Chlamydophila psittaci/genética , Psitacose/epidemiologia , Psitacose/veterinária , Aves Domésticas , Fazendeiros , Filogenia , Galinhas , Doenças das Aves Domésticas/epidemiologia , Patos , China/epidemiologia
14.
Front Cell Infect Microbiol ; 12: 1044984, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36590592

RESUMO

Introduction: Psittacosis, caused by Chlamydia psittaci, is widespread throughout the world. In humans, C. psittaci infection may lead to severe conditions and complications, including sepsis and multiple organ failure. We report a cluster of cases caused by C. psittaci in Zhejiang Province, 2021, which led to one death and three cases of hospitalization. Methods: The cases were confirmed by nest-PCR, RT-PCR, and mNGS. Results: The four cases were related and the sequences obtained from the samples were closely correlated with those from Taiwan. Discussion: This study is the first to report on the case of death from psittacosis in Zhejiang Province, and our results help to assess the disease and recommend effective measures to prevent further spread of C. psittaci.


Assuntos
Chlamydophila psittaci , Psitacose , Humanos , Psitacose/diagnóstico , Psitacose/epidemiologia , Chlamydophila psittaci/genética , China/epidemiologia , Reação em Cadeia da Polimerase
15.
Pharmaceuticals (Basel) ; 15(8)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36015166

RESUMO

Ischemic stroke leads to hypoxia-induced neuronal death and behavioral abnormity, and is a major cause of death in the modern society. However, the treatments of this disease are limited. Brilliant Blue FCF (BBF) is an edible pigment used in the food industry that with multiple aromatic rings and sulfonic acid groups in its structure. BBF and its derivatives were proved to cross the blood-brain barrier and have advantages on the therapy of neuropsychiatric diseases. In this study, BBF, but not its derivatives, significantly ameliorated chemical hypoxia-induced cell death in HT22 hippocampal neuronal cell line. Moreover, protective effects of BBF were attributed to the inhibition of the extracellular regulated protein kinase (ERK) and glycogen synthase kinase-3ß (GSK3ß) pathways as evidenced by Western blotting analysis and specific inhibitors. Furthermore, BBF significantly reduced neurological and behavioral abnormity, and decreased brain infarct volume and cerebral edema induced by middle cerebral artery occlusion/reperfusion (MCAO) in rats. MCAO-induced increase of p-ERK in ischemic penumbra was reduced by BBF in rats. These results suggested that BBF prevented chemical hypoxia-induced otoxicity and MCAO-induced behavioral abnormity via the inhibition of the ERK and GSK3ß pathways, indicating the potential use of BBF for treating ischemic stroke.

16.
Water Sci Technol ; 64(6): 1284-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22214082

RESUMO

Quorum sensing (QS) is a form of microbial communication that relies on small signal molecules to regulate group behaviors such as biofilm formation in response to population density. In this study, we attempted to apply the paradigm of bacterial QS to aerobic granular sludge (AGS) formation for wastewater treatment. An essential element of interspecies QS signals, boron, was added to a sequencing batch reactor (SBR) to stimulate AGS growth. Bioassays elaborated the activity of autoinducer-2 (AI-2). We found that boron accelerated AGS growth, resulting in improved settlement performance and increased biomass in the SBR. During continuous SBR operation, the AGS showed an obvious increase in AI-2 activity, which implies that interspecies QS was closely associated with AGS formation. Analysis of EPS showed that boron stimulated tryptophan production, and increased the hydrophobia of AGS. From these results, it was speculated that the addition of boron may have promoted the formation of boron complexed to (R)-4, 5-dihydroxy-2,3-pentanedione (DPD) as the precursor of AI-2, which resulted in accelerated interspecies QS. The results also suggested QS as a novel regulation target for the biogranulation process, such as AGS formation.


Assuntos
Percepção de Quorum , Boro/metabolismo , Esgotos/microbiologia
17.
Water Res ; 190: 116721, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33326896

RESUMO

Intermittent (every other day) microaerobic [picomolar oxygen by oxidation-reduction potential (ORP) set at +25 mV above anaerobic baseline] digestion of lignocellulosic biomass showed higher digestibility and better stability at a high organic loading rate (OLR) of 5 g volatile solids (VS)/L/d than that under strict anaerobic conditions. However, the microbial mechanisms supporting the delicate balance under microaeration remain underexplored. On the basis of our previous findings that microbial communities in replicate experiments were dominated by strains of the genus Proteiniphilum but contained diverse taxa of methanogenic archaea, here we recovered related genomes and reconstructed the putative metabolic pathways using a genome-centric metagenomic approach. The highly enriched Proteiniphilum strains were identified as efficient cellulolytic facultative bacterium, which directly degraded lignocellulose to carbon dioxide, formate, and acetate via aerobic respiration and anaerobic fermentation, alternatively. Moreover, high oxygen affinity cytochromes, bd-type terminal oxidases, in Proteiniphilum strains were found to be closely associated with such picomolar oxygen conditions, which has long been overlooked in anaerobic digestion. Furthermore, hydrogenotrophic methanogenesis was the prevalent pathway for methane production while Methanosarcina, Methanobrevibacter, and Methanocorpusculum were the dominant methanogens in the replicate experiments. Importantly, the two functional groups, namely cellulolytic facultative Proteiniphilum strains and methanogens, encoded various antioxidant enzymes. Energy-dependent reactive oxygen species (ROS) scavengers (superoxide reductase (SOR) and rubrerythrin (rbr) were ubiquitously present in different methanogenic taxa in response to replicate-specific ORP levels (-470, -450 and -475 mV). Collectively, cytochrome bd oxidase and ROS defenders may play roles in improving the digestibility and stability observed in intermittent microaerobic digestion.


Assuntos
Citocromos , Metano , Anaerobiose , Biomassa , Reatores Biológicos , Citocromos/metabolismo , Lignina , Espécies Reativas de Oxigênio
18.
Bioresour Technol ; 333: 125148, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33878497

RESUMO

Anaerobic digestion (AD) is a promising technology to recover bioenergy from biodegradable biomass, including cellulosic wastes. Through a few fractionation/separation techniques, cellulose has demonstrated its potential in AD, but the performance of the process is rather substrate-specific, as cellulolysis bacteria are sensitive to the enzyme-substrate interactions. Cellulosome is a self-assembled enzyme complex with many functionalized modules in the bacteria which has been gradually studied, however the genomic fingerprints of the culture-specific cellulosome in AD are relatively unclear especially under processing conditions. To clarify the key factors affecting the cellulosome induced cellulolysis, this review summarized the most recent publications of AD regarding the fates of cellulose, sources and functional genes of cellulosome, and omics methods for functional analyses. Different processes for organic treatment including applying food grinds in sewer, biomass valorization, cellulose fractionation, microaeration, and enzymatic hydrolysis enhanced fermentation, were highlighted to support the sustainable development of AD technology.


Assuntos
Celulossomas , Anaerobiose , Biomassa , Celulossomas/metabolismo , Genômica , Hidrólise
19.
J Agric Food Chem ; 69(34): 9764-9777, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34404210

RESUMO

The marine natural product fucoxanthin has been reported previously to produce anti-Alzheimer's disease (AD) neuroprotective effects in vitro and in vivo. Fucoxanthin was also demonstrated to be safe in preclinical and small population clinical studies, but the low bioavailability of fucoxanthin in the central nervous system (CNS) has limited its clinical applications. To overcome this, poly lactic-co-glycolic acid-block-polyethylene glycol loaded fucoxanthin (PLGA-PEG-Fuc) nanoparticles with diameter at around 200 nm and negative charge were synthesized and suggested to penetrate into the CNS. Loaded fucoxanthin could be liberated from PLGA-PEG nanoparticles by sustained released in the physiological environment. PLGA-PEG-Fuc nanoparticles were shown to significantly inhibit the formation of Aß fibrils and oligomers. Moreover, these nanoparticles were taken up by both neurons and microglia, leading to the reduction of Aß oligomers-induced neurotoxicity in vitro. Most importantly, intravenous injection of PLGA-PEG-Fuc nanoparticles prevented cognitive impairments in Aß oligomers-induced AD mice with greater efficacy than free fucoxanthin, possibly via acting on Nrf2 and NF-κB signaling pathways. These results altogether suggest that PLGA-PEG nanoparticles can enhance the bioavailability of fucoxanthin and potentiate its efficacy for the treatment of AD, thus potentially enabling its future use for AD therapy.


Assuntos
Nanopartículas , Phaeophyceae , Peptídeos beta-Amiloides , Animais , Carotenoides , Portadores de Fármacos , Camundongos , Polietilenoglicóis , Xantofilas
20.
Microorganisms ; 8(6)2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32570720

RESUMO

Single-stage nitrite shunt denitrification (through nitrite rather than nitrate) with low dissolved oxygen (DO) supply is a better alternative in terms of energy-efficiency, short-footprint, and low C/N-ratio requirement. This study investigates the optimal DO level with temperature effect, with saline sewage at the fixed hydraulic and solids retention times of 8 h and 8 d, respectively. Moreover, 16S rRNA gene sequencing analysis corresponding with total nitrogen (TN) and chemical oxygen demand (COD) removals in each operating condition were performed. Results showed that DO of 0.3 mg/L at 20 °C achieved over 60.7% and over 97.9% of TN and COD removal, respectively, suggesting that such condition achieved effective nitrite-oxidizing bacteria inhibition and efficient denitrification. An unexpected finding was that sulfur-reducing Haematobacter and nitrogen-fixing Geofilum and Shinella were highly abundant with the copredominance of ammonia-oxidizing Comamonas and Nitrosomonas, nitrite-oxidizing Limnohabitans, and denitrifying Simplicispira, Castellaniella, and Nitratireductor. Further, canonical correspondence analysis (CCA) with respect to the operating conditions associated with phenotype prediction via R-based tool Tax4Fun was performed for a preliminary diagnosis of microbial functionality. The effects of DO, temperature, nitrite, and nitrate in various extents toward each predominant microbe were discussed. Collectively, DO is likely pivotal in single-stage nitrite shunt denitrification, as well as microbial communities, for energy-efficient saline sewage treatment.

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