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1.
Environ Res ; 255: 119139, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750996

RESUMO

As wastewater contains a variety of contaminating bacteria and oily residues, there is an urgent need for environmentally safe bactericidal agents and surfactants which can be applied for wastewater treatment. The present study emphasizes on the potential of hydrophobin-like protein (HFB-NJ1) extracted from sporulating mycelia of Aspergillus sp. NJ1 for wastewater treatment. The purified HFB-NJ1, depicted the presence of one single protein band of molecular size approximately 11-12 kDa on silver-stained SDS-PAGE gel. HFB-NJ1 also presented properties such as surface modification of glass and stable emulsification of sunflower oil. HFB-NJ1 depicted exceptional antibacterial activity against bacterial pathogens such as Bacillus subtilis and Pseudomonas aeruginosa at low MIC of 0.5 µg/mL and 0.75 µg/mL respectively. Additionally, HFB-NJ1 depicted enhanced emulsification of various vegetable and petroleum-based oils (E24 > 80%). HFB-NJ1 effectively reduced gold ions, producing nanospheres with a size of 15.33 nm - a recognized antimicrobial agent. This study underscores the multifunctional attributes of HFB-NJ1, highlighting its efficacy in removing pathogenic bacteria, emulsifying organic compounds from wastewater, and demonstrating a reduction ability for nanoparticle synthesis.


Assuntos
Proteínas Fúngicas , Águas Residuárias , Águas Residuárias/química , Proteínas Fúngicas/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Aspergillus/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Eliminação de Resíduos Líquidos/métodos , Bacillus subtilis/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Purificação da Água/métodos
2.
Environ Res ; 252(Pt 1): 118783, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38570125

RESUMO

In this work Full Potential study performed on Lanthanum compounds to analyze its photovoltaic properties. Five different combinations of Lanthanum and Indium with phosphorus are chosen in this study are La3P, La2InP, LaIn2P, LaP and InP. The optical, structural, thermoelectric, thermal, and electronic properties of all the above-mentioned compounds are analyzed using Density Functional Theory (DFT) applied in the WIEN2k software. Based on the analysis of electronic properties is concluded that La3P, LaP, La2InP and LaIn2P are conductors whereas InP is semiconductor (direct band gap) with band gap (energy) value 0.39 eV. The optical properties analysis shows these materials have desirable properties in the near UV or in the UV region. The low value of Gibbs energy indicates high thermodynamic stability. Power factor values for La2InP, LaP, InP and La3P are found to be in agreement with existing thermoelectric material, rendering them as potential thermal photovoltaic materials.


Assuntos
Índio , Lantânio , Nanoestruturas , Lantânio/química , Lantânio/análise , Índio/química , Nanoestruturas/química , Energia Solar
3.
Environ Res ; 252(Pt 4): 119030, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677409

RESUMO

Bifunctional electrocatalysts are the attractive research in the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in the overall water-splitting reactions. The design and development of the cost-effective OER/HER bifunctional electrocatalysts with superior catalytic activity are still remaining as the big challenges. Herein, we have developed the CuO-ZnO nanocomposite as a bifunctional OER/HER electrocatalyst via simple chemical precipitation method. The nanocomposite was investigated for its crystalline structure, surface morphology and the functions of elements using XRD, FT-IR, SEM, TEM and XPS characterization techniques, respectively. The nanocomposite exhibited the excellent activity for the overall water-splitting in an alkaline medium. The CuO-ZnO nanocomposite showed the less onset potential of 1.4 and 0.15 V versus RHE in 1M KOH (Tafel slopes value of 0.180 and 0.400 V dec-1) for OER and HER, respectively. Hence, the as-prepared bifunctional electrocatalyst displayed the high stability for 10 h in the water electrolysis processes.


Assuntos
Cobre , Oxigênio , Óxido de Zinco , Cobre/química , Óxido de Zinco/química , Catálise , Oxigênio/química , Hidrogênio/química , Técnicas Eletroquímicas , Nanocompostos/química , Nanoestruturas/química , Água/química , Eletrólise
4.
Environ Res ; 241: 117549, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37931737

RESUMO

Since ecosystems are becoming inherently polluted, long-term contaminant removal methods are required. Electrodeionization, in particular, has recently been demonstrated as an effective approach for eliminating ionic compounds from contaminated water sources. Being a more environmentally friendly technology is most likely the main reason for its eminence. It uses electricity to replace toxic contaminants that are conventionally used to regenerate and hence reducing the toxins associated with resin regeneration. In wastewater treatment, continuous electrodeionization system overcomes several limitations of ion exchange resins, notably ion dumping. This prospective assessment delves into the mechanism, principle, and theory of electrodeionization system. It also focused on the design and applications, particularly in the removal of toxic compounds, as well as current advances in the electrodeionization system. Recent breakthroughs in electrodeionization were comprehensively discussed. Further developments in electrodeionization systems are also projected, with improved efficiency at the time of functioning at lower costs because of reduced energy use, proving them desirable for commercial usage with a broad array of applications across the globe.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Ecossistema , Estudos Prospectivos , Íons , Água
5.
Chemosphere ; 314: 137492, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36481170

RESUMO

The n-type Ce doped ZnO (Ce-ZnO) and p-type polyaniline (PANI) heterojunction were successfully synthesized via simple chemical solution method for sensing liquefied petroleum gas (LPG) at standard environment. The morphology and structures of as-prepared Ce-ZnO & PANI nanoparticles were analyzed by numerous kinds of techniques. Ce-ZnO & PANI nanoparticles were mixed with n-methylpyrrolidone (NMP) which is coated over the gold coated PET electrode by doctor blade method and dried overnight at 60 °C to form p-n junction. The as-formed p-n junction is to be driven with the help of 1.5 V potential at ambient temperature. X-ray photoelectron spectroscopy results of Ce-ZnO nanoparticles confirmed the existence of Ce4+ and the improved amount of both chemisorbed oxygen and oxygen vacancy after the formation of Ce-ZnO heterojunction. The maximum response of 80% was realized for hollow Ce-ZnO/PANI sensor at 100 ppm. The proposed material is a novel candidate to detect the LPG even at low (30) ppm and this study reveals the possibility of developing a potentially inexpensive hollow Ce-ZnO/PANI sensor for sensing LPG efficiently.


Assuntos
Petróleo , Óxido de Zinco , Oxigênio , Tomografia por Emissão de Pósitrons
6.
Int J Biol Macromol ; 186: 125-134, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34246666

RESUMO

Marine microorganisms are reported to produce polyhydroxybutyrate (PHB) that has wide range of medical and industrial applications with the advantage of biodegradability. PHBs are synthesized as an energy and carbon storage element under metabolic pressure. The scope of this work is enhancing PHB production using marine microbial isolate, Micrococcus luteus by selectively optimizing various growth conditions such as different media components and growth parameters that influence the cell growth and PHB production were sampled. Micrococcus luteus produced 7.54 g/L of PHB utilizing glucose as a carbon source and ammonium sulphate as a nitrogen source with maximum efficiency. The same optimized operational conditions were further employed in batch fermentation over a time span of 72 h. Interestingly higher cell dry weight of 21.52 g/L with PHB yield of 12.18 g/L and 56.59% polymer content was observed in batch fermentation studies at 64 h. The chemical nature of the extracted polymer was validated with physio-chemical experiments and was at par with the commercially available PHB. This study will spotlight M. luteus as a potential source for large-scale industrial production of PHB with reducing environmental pollutions.


Assuntos
Butiratos/metabolismo , Sedimentos Geológicos/microbiologia , Hidroxibutiratos/isolamento & purificação , Microbiologia Industrial , Micrococcus luteus/metabolismo , Butiratos/química , Fermentação , Concentração de Íons de Hidrogênio , Micrococcus luteus/crescimento & desenvolvimento , Estrutura Molecular , Temperatura , Fatores de Tempo
7.
Sci Total Environ ; 731: 138049, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32408201

RESUMO

An increase in population, rapid urbanization and industrialization has accelerated the rate of municipal solid waste generation. The current disposal of solid waste is a burgeoning issue and it's in immediate need to shift the existing disposal processes to a sustainable manner. Circular economy (CE) is a conceptual model which is been used for better use of resources and minimization of waste in a closed loop approach which could be appropriate for waste management. In this context, the present review illustrates the effective use of biodegradable and non-biodegradable fraction of solid waste in a closed loop integrated refinery platforms for the recovery of bioenergy resources and for the production of value added products. The biodegradable fraction of solid waste could be treated by advanced biological processes with the simultaneous production of bioenergy such as biohydrogen, biomethane, bioelectricity, etc., and other value added products like butanol, ethanol, methanol etc. The scheme illustrates the closed loop approach, the bioenergy generated from the biodegradable fraction of solid waste could be used for the operation of internal combustion engines and the energy could be further used for processing the waste. The non-biodegradable fraction of solid waste could be used for construction and pavement processes. Overall the study emphasizes the paradigm shift of solid waste management concepts from linear economy to a circular economy following the "Zero Waste" concept. The study also explains the circular economy policies practiced for solid waste management that stimulates the economy of the country and identify the pathways to maximize the local resources. In addition the review addresses the advanced information and communication technologies to unfold the issues and challenges faced in the solid waste management. The smart governance of managing waste using the "Internet of Things" (IoT) is one of the great precursors of technological development that could lead innovations in waste management.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Modelos Teóricos , Resíduos Sólidos/análise
8.
J Photochem Photobiol B ; 202: 111636, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31739259

RESUMO

Titanium dioxide (TiO2) nanoparticles (NPs) have been doped with varying amounts (0.005, 0.010 and 0.015 M) of silver nanoparticles (Ag NPs) using hydrothermal method. Further, in this work, a green approach was followed for the formation of Ag@TiO2 NPs using Aloe vera gel as a capping and reducing agent. The structural property confirmed the presence of anatase phase TiO2. Increased peak intensity was observed while increasing the Ag concentration. Further, the morphological and optical properties have been studied, which confirmed the effective photocatalytic behavior of the prepared Ag@TiO2 NPs. The photocatalytic performance of Ag@TiO2 has been considered for the degradation of picric acid in the visible light region. The concentration at 0.010 M of the prepared Ag@TiO2 has achieved higher photocatalytic performance within 50 min, which could be attributed to its morphological behavior. Similarly, anticancer activity against lung cancer cell lines (A549) was also determined. The Ag@TiO2 NPs generated a large quantity of reactive oxygen species (ROS), resulting in complete cancer cell growth suppression after their systemic in vitro administration. Ag@TiO2 NPs was adsorbed visible light that leads to an enhanced anticancer sensitivity by killing and inhibiting cancer cell reproduction through cell viability assay test. It was clear that 0.015 M of Ag@TiO2 NPs were highly effective against human lung cancer cell lines and showed increased production of ROS in cancer cell lines due to the medicinal behavior of the Aloe vera gel.


Assuntos
Antineoplásicos/química , Nanopartículas Metálicas/química , Prata/química , Titânio/química , Células A549 , Aloe/química , Aloe/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Catálise , Sobrevivência Celular/efeitos dos fármacos , Química Verde , Humanos , Luz , Nanopartículas Metálicas/toxicidade , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
Biomed Pharmacother ; 92: 479-490, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28570982

RESUMO

In the recent years, synthesis of nanomaterials using seaweeds and their diverse applications is escalating research in modern era. Among the noble metals, platinum nanoparticles (PtNPs) are of great importance owing to their catalytic property and less toxicity. The significance of this work is a simple one-step synthesis of PtNPs using aqueous extract of Indian brown seaweed Padina gymnospora and their catalytic activity with a polymer Polyvinylpyrrolidone (PVP) as PVP/PtNPs nanocomposite towards antimicrobial, haemolytic, cytotoxic (Artemia salina) and antioxidant properties. Fourier Transform Infrared (FT-IR) spectrum results showed diversified functional groups (biomoeities such as carbohydrates and proteins) present in the seaweed extract is responsible for the reduction of platinum ions (Pt+) to PtNPs. The seaweed mediated PtNPs was characterized by UV-vis spectrophotometer, X-ray diffraction (XRD) pattern, Field Emission Scanning Electron Microscopy (FESEM) equipped with Energy Dispersive X-ray (EDX) spectroscopy and High Resolution Transmission Electron Microscopy (HRTEM) analysis. The synthesized PtNPs was found to be truncated octahedral in shape with the range of 5-50nm. Crystalline nature of the nanoparticles was evidenced by Selected Area Electron Diffraction (SAED) pattern with bright circular spots corresponding to (111), (200), (220) and (311) Bragg's reflection planes. The size of the PtNPs was further evidenced by Dynamic Light Scattering (DLS) analysis and it is originate to be stable at -22.5mV through Zeta Potential (ZP) analysis. The present study shows that the catalytic behavior of PtNPs as polymer/metal nanocomposite (PVP/PtNPs) preparation for an antibacterial activity against seven disease causing pathogenic bacterial strains with the maximum activity against Escherichia coli (15.6mm) followed by Lactococcus lactis (14.8mm) and Klebsiella pneumoniae (14.4mm). But no haemolytic activity was seen at their effective bactericidal concentration, whereas increase in the haeomyltic activity was seen only in higher concentrations (600, 900 and 1200µgmL-1). On the other hand, PVP/PtNPs nanocomposite has shown cytotoxic activity at 100±4µgmL-1 (LC50) against Artemia salina nauplii. Furthermore, PVP/PtNPs nanocomposite showed an enhanced scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide, nitric oxide and hydroxyl radicals.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Nanocompostos/química , Platina/química , Povidona/síntese química , Alga Marinha , Animais , Antibacterianos/síntese química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Catálise/efeitos dos fármacos , Relação Dose-Resposta a Droga , Hemólise/efeitos dos fármacos , Hemólise/fisiologia , Humanos , Nanopartículas Metálicas/administração & dosagem , Testes de Sensibilidade Microbiana/métodos , Nanocompostos/administração & dosagem , Phaeophyceae , Platina/metabolismo , Platina/farmacologia , Povidona/metabolismo , Povidona/farmacologia , Alga Marinha/metabolismo
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