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1.
Mol Microbiol ; 121(6): 1164-1181, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38676355

RESUMO

Latent tuberculosis, caused by dormant Mycobacterium tuberculosis (Mtb), poses a threat to global health through the incubation of undiagnosed infections within the community. Dormant Mtb, which is phenotypically tolerant to antibiotics, accumulates triacylglycerol (TAG) utilizing fatty acids obtained from macrophage lipid droplets. TAG is vital to mycobacteria, serving as a cell envelope component and energy reservoir during latency. TAG synthesis occurs by sequential acylation of glycerol-3-phosphate, wherein the second acylation step is catalyzed by acylglycerol-3-phosphate acyltransferase (AGPAT), resulting in the production of phosphatidic acid (PA), a precursor for the synthesis of TAG and various phospholipids. Here, we have characterized a putative acyltransferase of Mtb encoded by Rv3816c. We found that Rv3816c has all four characteristic motifs of AGPAT, exists as a membrane-bound enzyme, and functions as 1-acylglycerol-3-phosphate acyltransferase. The enzyme could transfer the acyl group to acylglycerol-3-phosphate (LPA) from monounsaturated fatty acyl-coenzyme A of chain length 16 or 18 to produce PA. Complementation of Escherichia coli PlsC mutant in vivo by Rv3816c confirmed that it functions as AGPAT. Its active site mutants, H43A and D48A, were incapable of transferring the acyl group to LPA in vitro and were not able to rescue the growth defect of E. coli PlsC mutant in vivo. Identifying Rv3816c as AGPAT and comparing its properties with other AGPAT homologs is not only a step toward understanding the TAG biosynthesis in mycobacteria but has the potential to explore it as a drug target.


Assuntos
Mycobacterium tuberculosis , Triglicerídeos , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Triglicerídeos/biossíntese , Triglicerídeos/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , 1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Glicerol-3-Fosfato O-Aciltransferase/genética , Aciltransferases/metabolismo , Aciltransferases/genética , Acilação , Ácidos Graxos/metabolismo , Ácidos Graxos/biossíntese , Ácidos Fosfatídicos/metabolismo , Ácidos Fosfatídicos/biossíntese , Acil Coenzima A/metabolismo
2.
Sensors (Basel) ; 22(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36146130

RESUMO

Deep learning (DL) enables the creation of computational models comprising multiple processing layers that learn data representations at multiple levels of abstraction. In the recent past, the use of deep learning has been proliferating, yielding promising results in applications across a growing number of fields, most notably in image processing, medical image analysis, data analysis, and bioinformatics. DL algorithms have also had a significant positive impact through yielding improvements in screening, recognition, segmentation, prediction, and classification applications across different domains of healthcare, such as those concerning the abdomen, cardiac, pathology, and retina. Given the extensive body of recent scientific contributions in this discipline, a comprehensive review of deep learning developments in the domain of diabetic retinopathy (DR) analysis, viz., screening, segmentation, prediction, classification, and validation, is presented here. A critical analysis of the relevant reported techniques is carried out, and the associated advantages and limitations highlighted, culminating in the identification of research gaps and future challenges that help to inform the research community to develop more efficient, robust, and accurate DL models for the various challenges in the monitoring and diagnosis of DR.


Assuntos
Aprendizado Profundo , Diabetes Mellitus , Retinopatia Diabética , Algoritmos , Retinopatia Diabética/diagnóstico , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Aprendizado de Máquina
3.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36555269

RESUMO

Root-zone restriction induces physiological stress on roots, thus limiting the vegetative and enhancing reproductive development, which promotes fruit quality and growth. Numerous bacterial-related growth-promoting, stress-mitigating, and disease-prevention activities have been described, but none in root-restricted cultivation. The study aimed to understand the activities of grapevine bacterial communities and plant-bacterial relationships to improve fruit quality. We used High-throughput sequencing, edaphic soil factors, and network analysis to explore the impact of restricted cultivation on the diversity, composition and network structure of bacterial communities of rhizosphere soil, roots, leaves, flowers and berries. The bacterial richness, diversity, and networking were indeed regulated by root-zone restriction at all phenological stages, with a peak at the veraison stage, yielding superior fruit quality compared to control plants. Moreover, it also handled the nutrient availability in treated plants, such as available nitrogen (AN) was 3.5, 5.7 and 0.9 folds scarcer at full bloom, veraison and maturity stages, respectively, compared to control plants. Biochemical indicators of the berry have proved that high-quality berry is yielded in association with the bacteria. Cyanobacteria were most abundant in the phyllosphere, Proteobacteria in the rhizosphere, and Firmicutes and Bacteroidetes in the endosphere. These bacterial phyla were most correlated and influenced by different soil factors in control and treated plants. Our findings are a comprehensive approach to the implications of root-zone restriction on the bacterial microbiota, which will assist in directing a more focused procedure to uncover the precise mechanism, which is still undiscovered.


Assuntos
Microbiota , Solo , Solo/química , Microbiologia do Solo , Rizosfera , Microbiota/fisiologia , Bactérias/genética , Plantas , Raízes de Plantas/microbiologia
4.
Molecules ; 26(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065194

RESUMO

Diabetes mellitus (DM) is a chronic disorder and has affected a large number of people worldwide. Insufficient insulin production causes an increase in blood glucose level that results in DM. To lower the blood glucose level, various drugs are employed that block the activity of the α-glucosidase enzyme, which is considered responsible for the breakdown of polysaccharides into monosaccharides leading to an increase in the intestinal blood glucose level. We have synthesized novel 2-(3-(benzoyl/4-bromobenzoyl)-4-hydroxy-1,1-dioxido-2H-benzo[e][1,2]thiazin-2-yl)-N-arylacetamides and have screened them for their in silico and in vitro α-glucosidase inhibition activity. The derivatives 11c, 12a, 12d, 12e, and 12g emerged as potent inhibitors of the α-glucosidase enzyme. These compounds exhibited good docking scores and excellent binding interactions with the selected residues (Asp203, Asp542, Asp327, His600, Arg526) during in silico screening. Similarly, these compounds also showed good in vitro α-glucosidase inhibitions with IC50 values of 30.65, 18.25, 20.76, 35.14, and 24.24 µM, respectively, which were better than the standard drug, acarbose (IC50 = 58.8 µM). Furthermore, a good agreement was observed between in silico and in vitro modes of study.


Assuntos
Acetamidas/síntese química , Acetamidas/farmacologia , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Tiazinas/química , Tiazinas/farmacologia , Acetamidas/química , Acetamidas/uso terapêutico , Simulação por Computador , Diabetes Mellitus/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/uso terapêutico , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Tiazinas/síntese química
5.
Pak J Pharm Sci ; 34(4): 1429-1436, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34799318

RESUMO

In the management of cardiovascular disorders, medicines from herbal sources have played a vital role through centuries. The following study was commenced in order to lay possible pharmacological foundation associated with medicinal uses of edible fruit of Grewia asiatica in hypertension through in-vitro method. In this study isolated atrial preparation of Guinea pig was used where crude ethanolic extract of Grewia asiatica fruit (Ga.Cr) decreased the force and rate of spontaneous atrial contractions (0.03-10mg/kg). In isolated rat aortic ring preparations previously vasoconstricted by phenylephrine and High K+, it also resulted in dose dependent vasodilation (0.01-10 mg/kg).In the presence of L-NAME, the relaxation curve of Ga.Cr was partially inhibited showing involvement of Nitric oxide (NO) mediated pathway. The speculative analysis contemplated that Ga.Cr has blood pressure reducing potentials through inhibition of Ca++ influx via Ca++ channels, its release from intracellular stores and through other means like NO mediated pathways.


Assuntos
Anti-Hipertensivos/farmacologia , Frutas/química , Grewia/química , Extratos Vegetais/farmacologia , Acetilcolina/farmacologia , Animais , Anti-Hipertensivos/isolamento & purificação , Aorta/efeitos dos fármacos , Aorta/fisiologia , Cobaias , Átrios do Coração/efeitos dos fármacos , Isoproterenol/farmacologia , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Extratos Vegetais/isolamento & purificação , Ratos , Ratos Sprague-Dawley
6.
J Biomed Inform ; 69: 230-250, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28433825

RESUMO

Nationwide health information exchange (NHIE) continues to be a persistent concern for government agencies, despite the many efforts and the conceived benefits of sharing patient data among healthcare providers. Difficulties in ensuring global connectivity, interoperability, and concerns on security have always hampered the government from successfully deploying NHIE. By looking at NHIE from a fresh perspective and bearing in mind the pervasiveness and power of modern mobile platforms, this paper proposes a new approach to NHIE that builds on the notion of consumer-mediated HIE, albeit without the focus on central health record banks. With the growing acceptance of smartphones as reliable, indispensable, and most personal devices, we suggest to leverage the concept of mobile personal health records (PHRs installed on smartphones) to the next level. We envision mPHRs that take the form of distributed storage units for health information, under the full control and direct possession of patients, who can have ready access to their personal data whenever needed. However, for the actual exchange of data with health information systems managed by healthcare providers, the latter have to be interoperable with patient-carried mPHRs. Computer industry has long ago solved a similar problem of interoperability between peripheral devices and operating systems. We borrow from that solution the idea of providing special interfaces between mPHRs and provider systems. This interface enables the two entities to communicate with no change to either end. The design and operation of the proposed approach is explained. Additional pointers on potential implementations are provided, and issues that pertain to any solution to implement NHIE are discussed.


Assuntos
Troca de Informação em Saúde , Smartphone , Registros de Saúde Pessoal , Humanos , Sistemas Computadorizados de Registros Médicos
7.
Appl Environ Microbiol ; 82(21): 6317-6325, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27542936

RESUMO

Hirsutella rhossiliensis is a parasite of juvenile nematodes, effective against a diversity of plant-parasitic nematodes. Its global distribution on various nematode hosts and its genetic variation for several geographic regions have been reported, while the global population genetic structure and factors underlying patterns of genetic variation of H. rhossiliensis are unclear. In this study, 87 H. rhossiliensis strains from five nematode species (Globodera sp., Criconemella xenoplax, Rotylenchus robustus, Heterodera schachtii, and Heterodera glycines) in Europe, the United States, and China were investigated by multilocus sequence analyses. A total of 280 variable sites (frequency, 0.6%) at eight loci and six clustering in high accordance with geographic populations or host nematode-associated populations were identified. Although H. rhossiliensis is currently recognized as an asexual fungus, recombination events were frequently detected. In addition, significant genetic isolation by geography and nematode hosts was revealed. Overall, our analyses showed that recombination, geographic isolation, and nematode host adaptation have played significant roles in the evolutionary history of H. rhossiliensis IMPORTANCE: H. rhossiliensis has great potential for use as a biocontrol agent to control nematodes in a sustainable manner as an endoparasitic fungus. Therefore, this study has important implications for the use of H. rhossiliensis as a biocontrol agent and provides interesting insights into the biology of this species.


Assuntos
Hypocreales/genética , Tylenchoidea/microbiologia , Adaptação Fisiológica , Animais , China , Cistos/microbiologia , Europa (Continente) , Variação Genética , Interações Hospedeiro-Parasita , Estágios do Ciclo de Vida , Recombinação Genética , Tylenchoidea/crescimento & desenvolvimento
8.
J Biomed Inform ; 53: 390-404, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25483886

RESUMO

Evaluating and selecting software packages that meet the requirements of an organization are difficult aspects of software engineering process. Selecting the wrong open-source EMR software package can be costly and may adversely affect business processes and functioning of the organization. This study aims to evaluate and select open-source EMR software packages based on multi-criteria decision-making. A hands-on study was performed and a set of open-source EMR software packages were implemented locally on separate virtual machines to examine the systems more closely. Several measures as evaluation basis were specified, and the systems were selected based a set of metric outcomes using Integrated Analytic Hierarchy Process (AHP) and TOPSIS. The experimental results showed that GNUmed and OpenEMR software can provide better basis on ranking score records than other open-source EMR software packages.


Assuntos
Registros Eletrônicos de Saúde , Informática Médica/métodos , Algoritmos , Tomada de Decisões , Lógica Fuzzy , Internet , Registro Médico Coordenado , Prontuários Médicos , Software , Design de Software
9.
J Med Syst ; 38(10): 133, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25199651

RESUMO

One of the applications of modern technology in telemedicine is video conferencing. An alternative to traveling to attend a conference or meeting, video conferencing is becoming increasingly popular among hospitals. By using this technology, doctors can help patients who are unable to physically visit hospitals. Video conferencing particularly benefits patients from rural areas, where good doctors are not always available. Telemedicine has proven to be a blessing to patients who have no access to the best treatment. A telemedicine system consists of customized hardware and software at two locations, namely, at the patient's and the doctor's end. In such cases, the video streams of the conferencing parties may contain highly sensitive information. Thus, real-time data security is one of the most important requirements when designing video conferencing systems. This study proposes a secure framework for video conferencing systems and a complete management solution for secure video conferencing groups. Java Media Framework Application Programming Interface classes are used to design and test the proposed secure framework. Real-time Transport Protocol over User Datagram Protocol is used to transmit the encrypted audio and video streams, and RSA and AES algorithms are used to provide the required security services. Results show that the encryption algorithm insignificantly increases the video conferencing computation time.


Assuntos
Segurança Computacional , Sistemas Computacionais , Telemedicina/métodos , Comunicação por Videoconferência , Confidencialidade , Linguagens de Programação , Software
10.
Int J Biol Macromol ; 272(Pt 1): 132532, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38806082

RESUMO

The study involved preparing and applying edible nano-emulsion coatings containing hydroxypropyl methylcellulose (HPMC), beeswax (BW), and essential oils (thyme, cinnamon, clove, and peppermint) onto sweet cherries. The application was conducted at 4 °C, and the coated cherries were stored for 36 days. This research examines synthesized nano-emulsions physicochemical properties and antibacterial and antifungal activities (C1, C2, and C3). Additionally, it evaluates the quality parameters of control and coated sweet cherry samples. The features of the three edible coatings were assessed, and the findings from the zeta sizer, zeta potential, FTIR, and SEM analyses were deemed satisfactory. It was observed that the application of nano-emulsion coating C1 yielded positive results in maintaining quality attributes such as total suspended solids (TSS), total solids (TS), color, weight loss, respiration rate, firmness, total phenolic contents, and sensory evaluations. Nano-emulsion coating C1 demonstrated efficacy as an antibacterial and antifungal agent against foodborne pathogens E. coli and A. niger, respectively. The current research results are promising and applicable in food industries. The implications suggest that composite nano-emulsion, specifically nano-emulsion edible coatings, can be extensively and effectively used to preserve the quality and shelf life of fruits and vegetables. Furthermore, the environmental waste from conventional food packaging will be minimized using edible packaging applications.


Assuntos
Derivados da Hipromelose , Óleos Voláteis , Ceras , Ceras/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Derivados da Hipromelose/química , Antibacterianos/farmacologia , Antibacterianos/química , Conservação de Alimentos/métodos , Armazenamento de Alimentos , Emulsões , Cymbopogon/química , Filmes Comestíveis , Antifúngicos/farmacologia , Antifúngicos/química , Escherichia coli/efeitos dos fármacos , Frutas/química
11.
Food Chem ; 453: 139612, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38772306

RESUMO

Fusarium oxysporum and Botrytis cinerea are the main pathogens that cause fruit decay and reduce the postharvest shelf life of cherry tomatoes. Boosting the potency of natural products requires implementing structural modification to combat postharvest pathogens. Herein, we developed a novel Vanillin-Deep Eutectic Agent (V-DEA) from natural compounds and evaluated its effectiveness against tomato fruit rot pathogens. The results demonstrated that V-DEA suppressed mycelium growth and spore germination of F. oxysporum and B. cinerea by enhancing cell membrane permeability, increasing lipid peroxidation, and inhibiting enzyme activities. Importantly, using 8-mM V-DEA successfully prevented postharvest decay in cherry tomatoes, while 4-mM significantly extended their shelf life by reducing weight loss and shriveling, and enhancing key fruit qualities such as total soluble solids, ascorbic acid, tartaric acid, and lycopene. In conclusion, V-DEA exhibits dual properties as a potent pathogen inhibitor and antioxidant activity, thus prolonging the shelf life of cherry tomatoes.


Assuntos
Benzaldeídos , Botrytis , Conservação de Alimentos , Frutas , Fusarium , Doenças das Plantas , Solanum lycopersicum , Solanum lycopersicum/microbiologia , Solanum lycopersicum/química , Solanum lycopersicum/crescimento & desenvolvimento , Benzaldeídos/farmacologia , Benzaldeídos/química , Botrytis/crescimento & desenvolvimento , Botrytis/efeitos dos fármacos , Conservação de Alimentos/métodos , Frutas/química , Frutas/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Armazenamento de Alimentos
12.
Int J Pharm ; 660: 124301, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851411

RESUMO

The application of gold nanoparticles (AuNPs) in cancer therapy, particularly targeted therapy of glioblastoma multiforme (GBM), is an up-and-coming field of research that has gained much interest in recent years. GBM is a life-threatening malignant tumour of the brain that currently has a 95 % death rate with an average of 15 months of survival. AuNPs have proven to have wide clinical implications and compelling therapeutic potential in many researches, specifically in GBM treatment. It was found that the reason why AuNPs were highly desired for GBM treatment was due to their unique properties that diversified the applications of AuNPs further to include imaging, diagnosis, and photothermal therapy. These properties include easy synthesis, biocompatibility, and surface functionalization. Various studies also underscored the ability of AuNPs to cross the blood-brain-barrier and selectively target tumour cells while displaying no major safety concerns which resulted in better therapy results. We attempt to bring together some of these studies in this review and provide a comprehensive overview of safety evaluations and current and potential applications of AuNPs in GBM therapy that may result in AuNP-mediated therapy to be the new gold standard for GBM treatment.

13.
Chemosphere ; 346: 140544, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37907169

RESUMO

2D-Ti3C2Tx MXene nanosheets intercalated with sodium ions (SI-Ti3C2Tx) were synthesized and utilized in simultaneous adsorption and electrochemical regeneration with ciprofloxacin (CPX). The primary focus of this study is to investigate the long-term stability of SI-Ti3C2Tx MXene and to propose the underlying regeneration mechanisms. The successful synthesis of Ti3AlC2, Ti3C2Tx MXene, and SI-Ti3C2Tx MXene was confirmed using X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. Electrochemical regeneration parameters such as charge passed, regeneration time, current density, and electrolyte composition were optimized with values of 787.5 C g-1, 7.5 min, 10 mA cm-2, and 2.5w/v% sodium chloride, respectively, enabling the complete regeneration of the SI-Ti3C2Tx MXene. In addition, the electrochemical regeneration significantly enhanced CPX removal from the SI-Ti3C2Tx MXene owing to partial amorphization, disorderliness, increased functional groups, delamination, and defect creation in the structure. Thus, the synthesized nano-adsorbent has proven helpful in practical water treatment with optimized electrochemical regeneration processes.


Assuntos
Ciprofloxacina , Cloreto de Sódio , Adsorção , Espectroscopia Fotoeletrônica
14.
Plant Physiol Biochem ; 196: 703-711, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36809731

RESUMO

Nanotechnology has enormous potential for sustainable agriculture, such as improving nutrient use efficiency, plant health, and food production. Nanoscale modulation of the plant-associated microbiota offers an additional valuable opportunity to increase global crop production and ensure future food and nutrient security. Nanomaterials (NMs) applied to agricultural crops can impact plant and soil microbiota, which offers valuable services to host plants, including the acquisition of nutrients, abiotic stress tolerance, and disease suppression. Dissecting the complex interactions between NMs and plants by integrating multi-omic approaches is providing new insights into how NMs can activate host responses and functionality as well as influence native microbial communities. Such nexus and moving beyond descriptive microbiome studies to hypothesis-driven research will foster microbiome engineering and open up opportunities for the development of synthetic microbial communities to provide agronomic solutions. Herein, we first summarize the significant role of NMs and the plant microbiome in crop productivity and then focus on NMs effects on plant-associated microbiota. We outline three urgent priority research areas and call for a transdisciplinary collaborative approach, involving plant scientists, soil scientists, environmental scientists, ecologists, microbiologists, taxonomists, chemists, physicists, and stakeholders, to advance nano-microbiome research. Detailed understanding of the nanomaterial-plant-microbiome interactions and the mechanisms underlying NMs-mediated shifts in the microbiome assembly and functions may help to exploit the services of both nano-objects and microbiota for next-generation crop health.


Assuntos
Agricultura , Microbiota , Solo , Produtos Agrícolas , Nanotecnologia , Microbiologia do Solo
15.
Trends Plant Sci ; 28(9): 987-990, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37394307

RESUMO

Plants release chemical signals to interact with their environment when exposed to stress. Khait and colleagues unveiled that plants 'verbalize' stress by emitting airborne sounds. These can train machine learning models to identify plant stressors. This unlocks a new path in plant-environment interactions research with multiple possibilities for future applications.


Assuntos
Acústica , Som , Aprendizado de Máquina , Plantas
16.
Micromachines (Basel) ; 14(8)2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37630069

RESUMO

The zeolitic imidazolate framework-67 (ZIF-67) adsorbent and its composites are known to effectively remove organic dyes from aqueous environments. Here, we report a unique crystalline MoS2@ZIF-67 nanocomposite adsorbent for the efficient removal of methyl orange (MO) dye from an aqueous medium. In situ synthetic techniques were used to fabricate a well-crystalline MoS2@ZIF-67 nanocomposite, which was then discovered to be a superior adsorbent to its constituents. The successful synthesis of the nanocomposite was confirmed using XRD, EDX, FTIR, and SEM. The MoS2@ZIF-67 nanocomposite exhibited faster adsorption kinetics and higher dye removal efficiency compared with its constituents. The adsorption kinetic data matched well with the pseudo-second-order model, which signifies that the MO adsorption on the nanocomposite is a chemically driven process. The Langmuir model successfully illustrated the MO dye adsorption on the nanocomposite through comparing the real data with adsorption isotherm models. However, it appears that the Freundlich adsorption isotherm model was also in competition with the Langmuir model. According to the acquired thermodynamics parameters, the adsorption of MO on the MoS2@ZIF-67 nanocomposite surface was determined to be spontaneous and exothermic. The findings of this research open an avenue for using the MoS2@ZIF-67 nanocomposite to efficiently remove organic dyes from wastewater efflux.

17.
Sci Total Environ ; 904: 166438, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37633397

RESUMO

The increasing footprints of lithium (Li) in agroecosystems combined with limited recycling options have raised uncertain consequences for important crops. Nitrogen (N2)-fixation by legumes is an important biological response process, but the cause and effect of Li exposure on plant root-nodule symbiosis and biological N2-fixation (BNF) potential are still unclear. Soybean as a model plant was exposed to Li at low (25 mg kg-1), medium (50 mg kg-1), and high (100 mg kg-1) concentrations. We found that soybean growth and nodulation capacity had a concentration-dependent response to Li. Li at 100 mg kg-1 reduced the nodule numbers, weight, and BNF potential of soybean in comparison to the low and medium levels. Significant shift in soybean growth and BNF after exposure to Li were associated with alteration in the nodule metabolic pathways involved in nitrogen uptake and metabolism (urea, glutamine and glutamate). Importantly, poor soybean nodulation after high Li exposure was due in part to a decreased abundance of bacterium Ensifer in the nodule bacterial community. Also, the dominant N2-fixing bacterium Ensifer was significantly correlated with carbon and nitrogen metabolic pathways. The findings of our study offer mechanistic insights into the environmental and biological impacts of Li on soybean root-nodule symbiosis and N2-acquisition and provide a pathway to develop strategies to mitigate the challenges posed by Li in agroecosystems.


Assuntos
Glycine max , Fixação de Nitrogênio , Nodulação , Lítio , Proteínas de Plantas/metabolismo , Simbiose , Nitrogênio/metabolismo
18.
Chemosphere ; 317: 137770, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36621685

RESUMO

Most bio-electrochemical systems (BESs) use biotic/abiotic electrode combinations, with platinum-based abiotic electrodes being the most common. However, the non-renewability, cost, and poisonous nature of such electrode systems based on noble metals are major bottlenecks in BES commercialisation. Microbial electrosynthesis (MES), which is a sustainable energy platform that simultaneously treats wastewater and produces chemical commodities, also faces the same problem. In this study, a dual bio-catalysed MES system with a biotic anode and cathode (MES-D) was tested and compared with a biotic cathode/abiotic anode system (MES-S). Different bio-electrochemical tests revealed improved BES performance in MES-D, with a 3.9-fold improvement in current density compared to that of MES-S. Volatile fatty acid (VFA) generation also increased 3.2-, 4.1-, and 1.8-fold in MES-D compared with that in MES-S for acetate, propionate, and butyrate, respectively. The improved performance of MES-D could be attributed to the microbial metabolism at the bioanode, which generated additional electrons, as well as accumulative VFA production by both the bioanode and biocathode chambers. Microbial community analysis revealed the enrichment of electroactive bacteria such as Proteobacteria (60%), Bacteroidetes (67%), and Firmicutes + Proteobacteria + Bacteroidetes (75%) on the MES-S cathode and MES-D cathode and anode, respectively. These results signify the potential of combined bioanode/biocathode BESs such as MES for application in improving energy and chemical commodity production.


Assuntos
Acetatos , Ácidos Graxos Voláteis , Águas Residuárias , Eletrodos , Dióxido de Carbono/metabolismo
19.
ACS Omega ; 8(21): 18891-18900, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37273618

RESUMO

Nonthermal plasma is a well-recognized environmentally advantageous method for producing green fuels. This work used different photocatalysts, including PZO, SxZO, and SxZCx for hydrogen production using an atmospheric argon coaxial dielectric barrier discharge (DBD)-based light source. The photocatalysts were produced using a sol-gel route. The DBD discharge column was filled with water, methanol, and the catalyst to run the reaction under argon plasma. The DBD reactor was operated with a 10 kV AC source to sustain plasma for water splitting. The light absorption study of the tested catalysts revealed a decrease in the band gap with an increase in the concentration of Sr and carbon nanotubes (CNTs) in the Sr/ZnO/CNTs series. The photocatalyst S25ZC2 demonstrated the lowest photoluminescence (PL) intensity, implying the most quenched recombination of charge carriers. The highest H2 evolution rate of 2760 µmol h-1 g-1 was possible with the S25ZC2 catalyst, and the lowest evolution rate of 56 µmol h-1 g-1 was observed with the PZO catalyst. The photocatalytic activity of S25ZC2 was initially high, which decreased slightly over time due to the deactivation of the photocatalyst. The photocatalytic activity decreased from 2760 to 1670 µmol h-1 g-1 at the end of the process.

20.
Sci Total Environ ; 855: 158700, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36113807

RESUMO

In mangrove wetlands, leaves make up a high proportion of the plant biomass and can accumulate heavy metals from contaminated sediment. Despite this, it is still unclear how heavy metal concentrations in leaves change as they develop and how metals in senescence leaves are recycled back into the mangrove ecosystems during decomposition. The present study aims to investigate the dynamics of six heavy metals (Cu, Zn, Cr, Ni, Cd, and Pb) in leaves of two common mangrove plants, Avicennia marina and Kandelia obovata, at different stages of development (young, mature, and senescent) and leaf litter decomposition (from 0 to 20 weeks). Based on litterbag experiments in a subtropical mangrove swamp, both plant species showed similar trends in alternations of the six heavy metals during leaf development, that was, decreased in Cu and Zn but increased in Pb, while Cr, Ni, and Cd remained steady. All heavy metals in litter gradually increased in concentration during decomposition. By the end of the 20-weeks decomposition, the concentrations of Cu, Zn, and Cd in decayed leaves were comparable to those in sediment, with Cu, Zn, and Cd at approximately 18, 75, and 0.2 mg·kg-1, respectively, while Cr (66 mg·kg-1), Ni (65 mg·kg-1), and Pb (55 mg·kg-1) were lower than those in sediment, indicating that metals were not retained in litter but recycled back to the sediment. Tannins in mangrove leaf litter might chelate heavy metals, affecting their migration and transformation of heavy metals in estuarine mangrove wetlands. The findings of our study provide insight into the interactions between toxic heavy metals and mangrove plant species during leaf development, representing the first example of how most metals would be retained in leaf litter during decomposition, thereby reducing their release to estuarine and marine ecosystems.


Assuntos
Avicennia , Metais Pesados , Rhizophoraceae , Poluentes Químicos da Água , Áreas Alagadas , Ecossistema , Sedimentos Geológicos , Cádmio , Chumbo , Monitoramento Ambiental , Metais Pesados/análise , Folhas de Planta/química , Plantas , Poluentes Químicos da Água/análise
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