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1.
J Environ Manage ; 359: 121063, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38704955

RESUMO

Due to the potential harm caused by emerging micro-pollutants to living organisms, contaminating water supplies by micro-pollutants like EDCs, pharmaceuticals, and microorganisms has become a concern in many countries. Considering both microbiological and micro-pollutant exposure risks associated with water use for agricultural/or household purposes, it is imperative to create a strategy for improving pollutant removal from treated wastewater that is both effective and affordable. Natural clay minerals efficiently remove contaminants from wastewater, though the pristine clay has less affinity to several organic pollutants. Hydrophilic polymers, viz., poly(ethylene glycol) (PEG), improve the dispersion of particles, flocculation processes, and surface properties. In this study, PEG grafted with attapulgite, thereby providing a high-specific surface-area, mesoporous materials for the adsorption of micro-pollutants like ciprofloxacin (CIP) and 17α-ethinylestradiol (EE2) at high rates. A gentle washing process regenerates the clay-polymer material several times with no performance loss, and the natural water implications show fair applicability of solid in decontaminating the CIP and EE2 in an aqueous medium. Further, greenly synthesized silver nanoparticles in situ disperse with the clay polymer efficiently remove the gram-positive and gram-negative bacterium viz., Bacillus subtilis, and Pseudomonas aeruginosa, which are commonly persistent in aquatic environments. The clay polymer outperformed a modified clay composite to eliminate microorganisms and organic micro-pollutants in significant quantities quickly. These results clearly show the importance of fibrous clay-polymer composite for water purification technologies.


Assuntos
Argila , Polímeros , Prata , Purificação da Água , Purificação da Água/métodos , Polímeros/química , Argila/química , Prata/química , Adsorção , Poluentes Químicos da Água/química , Águas Residuárias/química , Bactérias
2.
Sci Total Environ ; 929: 172560, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38641102

RESUMO

Lanthanum (La), the second most abundant rare earth element (REE) is emerging as an environmental issue, with the potential to impact ecosystems and human health. Major sources of soil contamination by La include agricultural, and industrial activities. Lanthanum is non-essential for plant growth but accumulates in various plant parts. The uptake of La by plants is intricately influenced by various factors such as soil pH, redox potential, cation exchange capacity, presence of organic acids and rhizosphere composition. These factors significantly impact the availability and absorption of La ions. Lanthanum impact on plants depends on soil characteristics, cultivated species, developmental stage, La concentration, treatment period, and growth conditions. Excessive La concentrations affect cell division, DNA structure, nutrient uptake, and photosynthesis and induce toxicity symptoms. Plants employ detoxification mechanisms like vacuolar sequestration, osmolyte synthesis, and antioxidant defense system. However, higher concentrations of La can overwhelm these defense mechanisms, leading to adverse effects on plant growth and development. Further, accumulation of La in plants increases the risk for human exposure. Strategies to mitigate La toxicity are, therefore, vital for ecosystem protection. The application of phytoremediation, supplementation, chelation, amendments, and biosorption techniques contributes to the mitigation of La toxicity. This review provides insights into La sources, uptake, toxicity, and alleviation strategies in plants. Identifying research gaps and discussing advancements aims to foster a holistic understanding and develop effective strategies for protecting plant health and ecosystem resilience against La contamination.


Assuntos
Biodegradação Ambiental , Lantânio , Plantas , Poluentes do Solo , Lantânio/toxicidade , Poluentes do Solo/toxicidade , Poluentes do Solo/metabolismo , Plantas/efeitos dos fármacos , Plantas/metabolismo , Solo/química
3.
Sci Total Environ ; 929: 172546, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38636858

RESUMO

Micro-pollutants (specifically antibiotics and personal care products) and potential bacterial contamination pose a severe threat to human health and marine life. The study derives indigenous novel fibrous hydrophobic nanocomposite, efficient in decontaminating the micro-pollutants (tetracycline (TC) and bisphenol A (BPA)) and potential pathogens (S. pyogenes and E. coli) from aqueous wastes. A facile method synthesizes the fibrous attapulgite (ATP)- poly(4-vinylpyridine-co-styrene) (PVP) framework decorated in situ with the Ag0 nanoparticles (ATP@PVP/Ag0). A greener method using the Artocarpus heterophyllus leaf extract derives the Ag0(NPs). Various analytical methods extensively characterize the materials. A comprehensive study that includes pH, concentration, background electrolytes, and ionic strength reveals the sorptive removal insights of TC and BPA utilizing the ATP@PVP solid. The elimination of tetracycline (TC) and bisphenol A (BPA) agrees well with the pseudo-second-order kinetics. The pH 3.07 and 6.06 favor removing TC and BPA with the capacity of 10.86 mg/g and 17.36 mg/g at 25 °C. The hydrogen bonding and hydrophobic interactions predominate the sorption mechanism, and the material shows remarkable stability and reusability in repeated sorption/desorption operations. Similarly, the natural water implications and flow-bed system show fair applicability of solid in decontaminating the TC and BPA in an aqueous medium. Further, the material ATP@PVP/Ag0 exhibits very high inhibition of potential pathogens S. pyogenes and E. coli and optimizes the solid dose and solution pH.


Assuntos
Compostos Benzidrílicos , Nanocompostos , Fenóis , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Fenóis/análise , Interações Hidrofóbicas e Hidrofílicas , Tetraciclina/química , Eliminação de Resíduos Líquidos/métodos , Bactérias , Águas Residuárias/química , Águas Residuárias/microbiologia , Escherichia coli
4.
Environ Sci Pollut Res Int ; 31(19): 27653-27678, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38598151

RESUMO

Mine tailings are the discarded materials resulting from mining processes after minerals have been extracted. They consist of leftover mineral fragments, excavated land masses, and disrupted ecosystems. The uncontrolled handling or discharge of tailings from abandoned mine lands (AMLs) poses a threat to the surrounding environment. Numerous untreated mine tailings have been abandoned globally, necessitating immediate reclamation and restoration efforts. The limited feasibility of conventional reclamation methods, such as cost and acceptability, presents challenges in reclaiming tailings around AMLs. This study focuses on phytorestoration as a sustainable method for treating mine tailings. Phytorestoration utilizes existing native plants on the mine sites while applying advanced principles of environmental biotechnology. These approaches can remediate toxic elements and simultaneously improve soil quality. The current study provides a global overview of phytorestoration methods, emphasizing the specifics of mine tailings and the research on native plant species to enhance restoration ecosystem services.


Assuntos
Mineração , Plantas , Solo , Biodegradação Ambiental , Ecossistema , Poluentes do Solo
5.
Sci Total Environ ; 925: 171433, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38458469

RESUMO

Soil salinization significantly affects crop production by reducing crop quality and decreasing yields. Climate change can intensify salinity-related challenges, making the task of achieving global food security more complex. To address the problem of elevated salinity stress in crops, nanoparticles (NPs) have emerged as a promising solution. NPs, characterized by their small size and extensive surface area, exhibit remarkable functionality and reactivity. Various types of NPs, including metal and metal oxide NPs, carbon-based NPs, polymer-based NPs, and modified NPs, have displayed potential for mitigating salinity stress in plants. However, the effectiveness of NPs application in alleviating plant stress is dependent upon multiple factors, such as NPs size, exposure duration, plant species, particle composition, and prevailing environmental conditions. Moreover, alterations to NPs surfaces through functionalization and coating also play a role in influencing plant tolerance to salinity stress. NPs can influence cellular processes by impacting signal transduction and gene expression. They counteract reactive oxygen species (ROS), regulate the water balance, enhance photosynthesis and nutrient uptake and promote plant growth and yield. The objective of this review is to discuss the positive impacts of diverse NPs on alleviating salinity stress within plants. The intricate mechanisms through which NPs accomplish this mitigation are also discussed. Furthermore, this review addresses existing research gaps, recent breakthroughs, and prospective avenues for utilizing NPs to combat salinity stress.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Resiliência Psicológica , Estudos Prospectivos , Agricultura , Produção Agrícola , Óxidos , Salinidade
6.
Sci Total Environ ; 912: 168826, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38042185

RESUMO

Cadmium (Cd) is a highly toxic heavy metal that adversely affects humans, animals, and plants, even at low concentrations. It is widely distributed and has both natural and anthropogenic sources. Plants readily absorb and distribute Cd in different parts. It may subsequently enter the food chain posing a risk to human health as it is known to be carcinogenic. Cd has a long half-life, resulting in its persistence in plants and animals. Cd toxicity disrupts crucial physiological and biochemical processes in plants, including reactive oxygen species (ROS) homeostasis, enzyme activities, photosynthesis, and nutrient uptake, leading to stunted growth and reduced biomass. Although plants have developed defense mechanisms to mitigate these damages, they are often inadequate to combat high Cd concentrations, resulting in yield losses. Nanoparticles (NPs), typically smaller than 100 nm, possess unique properties such as a large surface area and small size, making them highly reactive compared to their larger counterparts. NPs from diverse sources have shown potential for various agricultural applications, including their use as fertilizers, pesticides, and stress alleviators. Recently, NPs have emerged as a promising strategy to mitigate heavy metal stress, including Cd toxicity. They offer advantages, such as efficient absorption by crop plants, the reduction of Cd uptake, and the enhancement of mineral nutrition, antioxidant defenses, photosynthetic parameters, anatomical structure, and agronomic traits in Cd-stressed plants. The complex interaction of NPs with calcium ions (Ca2+), intracellular ROS, nitric oxide (NO), and phytohormones likely plays a significant role in alleviating Cd stress. This review aims to explore the positive impacts of diverse NPs in reducing Cd accumulation and toxicity while investigating their underlying mechanisms of action. Additionally, it discusses research gaps, recent advancements, and future prospects of utilizing NPs to alleviate Cd-induced stress, ultimately promoting improved plant growth and yield.


Assuntos
Nanopartículas , Poluentes do Solo , Humanos , Cádmio/toxicidade , Cádmio/química , Espécies Reativas de Oxigênio , Antioxidantes , Plantas , Nanopartículas/toxicidade
7.
Bio Protoc ; 13(10): e4677, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37261078

RESUMO

Cotton is a significant industrial crop, playing an essential role in the global economy that suffers several setbacks due to biotic and abiotic adversities. Despite such problems, biotechnological advances in cotton are limited because of genetic transformation and regeneration limitations. Here, we present a detailed protocol optimized based on previously published papers, along with our modifications. These involve changes in Agrobacterium concentration, co-cultivation time and temperature, hormones used for regeneration, media manipulation for embryogenic callus production, and efficient rescue of deformed embryos. Further, this protocol has been used in genetic studies on biotic and abiotic stress in cotton. This protocol assures a reproducible stable transgenic cotton development procedure via somatic embryogenesis that can be used by researchers worldwide. This protocol was validated in: Nat Biotechnol (2016), DOI: 10.1038/nbt.3665.

8.
Environ Sci Pollut Res Int ; 30(35): 83180-83197, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37358773

RESUMO

Chromium (Cr), one of the hazardous pollutants, exists predominantly as Cr(VI) and Cr(III) in the environment. Cr(VI) is more toxic than Cr(III) due to its high mobility and solubility. Elevated levels of Cr in agricultural soil due to various anthropogenic activities cause Cr accumulation in plants, resulting in a significant reduction in plant yield and quality due to Cr-induced physiological, biochemical and molecular alterations. It can infiltrate the food chain through crop plants and cause harmful effects in humans via biomagnification. Cr(VI) is linked to cancer in humans. Therefore, mitigation strategies are required to remediate Cr-polluted soils and limit its accumulation in plants for safe food production. Recent research on metal and metal oxide nanoparticles (NPs) has shown that they can effectively reduce Cr accumulation and phytotoxicity. The effects of these NPs are influenced by their type and dose, exposure method, plant species and experimental settings. In this review, we present an up-to-date compilation and comprehensive analysis of the existing literature regarding the process of uptake and distribution of Cr and impact and potential mechanisms of metal and metal oxide nanoparticles led mitigation of Cr-induced stress in plants. We have also discussed recent developments, existing research gaps and future research directions in the field of Cr stress mitigation by NPs in plants. Overall, this review can provide valuable insights in reducing Cr accumulation and toxicity using metal and metal oxide nanoparticles, thereby promoting safe and sustainable cultivation of food and phytostabilization of Cr-polluted soil.


Assuntos
Nanopartículas Metálicas , Poluentes do Solo , Humanos , Óxidos/análise , Poluentes do Solo/análise , Cromo/química , Plantas , Solo/química
9.
Indian J Ophthalmol ; 71(6): 2500-2503, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37322670

RESUMO

Purpose: Glaucoma is the second leading cause of blindness worldwide, affecting more than 64 million people aged 40-80. The best way to manage primary open-angle glaucoma (POAG) is by lowering the intraocular pressure (IOP). Netarsudil is a Rho kinase inhibitor, the only class of antiglaucoma medications that reorganizes the extracellular matrix to improve the aqueous outflow through the trabecular pathway. Methods: An open-label, real-world, multicentric, observation-based 3-month study was performed for assessing the safety and ocular hypotensive efficacy of netarsudil ophthalmic solution (0.02% w/v) in patients with elevated IOP. Patients were given netarsudil ophthalmic solution (0.02% w/v) as a first-line therapy. Diurnal IOP measurements, best-corrected visual acuity, and adverse event assessments were recorded at each of the five visits (Day-1: screening day and first dosing day; subsequent observations were taken at 2 weeks, 4 weeks, 6 weeks, and 3 months). Results: Four hundred and sixty-nine patients from 39 centers throughout India completed the study. The mean IOP at baseline of the affected eyes was 24.84 ± 6.39 mmHg (mean ± standard deviation). After the first dose, the IOP was measured after 2, 4, and 6 weeks, with the final measurement taken at 3 months. The percentage reduction in IOP in glaucoma patients after 3 months of once-daily netarsudil 0.02% w/v solution use was 33.34%. The adverse effects experienced by patients were not severe in the majority of cases. Some adverse effects observed were redness, irritation, itching, and others, but only a small number of patients experienced severe reactions, as reported in a decreasing order: redness > irritation > watering > itching > stinging > blurring. Conclusion: We found that netarsudil 0.02% w/v solution monotherapy when used as the first-line treatment in primary open-angle glaucoma and ocular hypertension was both safe and effective.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Glaucoma de Ângulo Aberto , Glaucoma , Hipertensão Ocular , Humanos , Soluções Oftálmicas , Hipertensão Ocular/diagnóstico , Glaucoma/tratamento farmacológico , Pressão Intraocular , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/tratamento farmacológico , Anti-Hipertensivos/uso terapêutico , Resultado do Tratamento
10.
Plant Sci ; 333: 111737, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37217034

RESUMO

Methanol is noxious to insect pests, but most plants do not make enough of it to shield themselves from encroaching insects. Methanol emission is known to increase in the instance of herbivory. In the current study, we showed that Aspergillus niger pectin methylesterase over-expression increases methanol emission and confers resistance to polyphagous insect pests on transgenic cotton plants by impeding the possible methanol detoxification pathways. Transgenic plants emitted ∼11 fold higher methanol displaying insect mortality of 96% and 93% in Helicoverpa armigera and Spodoptera litura, respectively. The larvae were unable to survive and finish their life cycle and the surviving larvae exhibited severe growth retardation. Insects try to detoxify methanol via catalase, carboxylesterase and cytochrome P450 monooxygenase enzymes, amongst which cytochrome P450 plays a major role in oxidizing methanol to formaldehyde and formaldehyde to formic acid, which is broken down into carbon dioxide and water. In our study, catalase and esterase enzymes were found to be upregulated, but cytochrome P450 monooxygenase levels were not much affected. Leaf disc assays and In-planta bioassays also showed 50-60% population reduction in the sap sucking pests, such as Bemisia tabaci and Phenacoccus solenopsis. These findings imply that elevated methanol emissions confer resistance in plants against chewing and sap-sucking pests by tampering the methanol detoxification pathways. Such mechanism will be useful in imparting expansive resistance against pests in plants.


Assuntos
Hemípteros , Mariposas , Animais , Metanol/metabolismo , Catalase/metabolismo , Gossypium/genética , Gossypium/metabolismo , Insetos/metabolismo , Mariposas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Larva/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo
11.
Sci Rep ; 13(1): 6209, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069316

RESUMO

In this work, five acrylonitrile adducts were screened for antibacterial activity against Gram-positive Bacillus subtilis, Microbial Type Culture Collection and Gene Bank (MTCC 1305) and Gram-negative Escherichia coli (MTCC 443). Synthesis was followed by aza-Michael addition reaction, where the acrylonitrile accepts an electron pair from the respective amines and results in the formation of n-alkyliminobis-propionitrile and n-alkyliminopropionitrile under microwave irradiation. Characterization of the compounds were performed using Fourier Transform Infrared (FTIR), Proton Nuclear Magnetic Resonance (1H NMR) and Electrospray Ionisation Mass Spectrometry (ESI-MS). The particle size characterization was done by Dynamic Light Scattering (DLS) technique. The antibacterial study showed higher inhibition rate for both Gram-positive and Gram-negative bacteria. The antibacterial ability was found to be dose dependent. The minimum inhibitory concentration against both bacteria were found to be 1, 3, 0.4, 1, 3 µl/ml for E. coli and 6, 6, 0.9, 0.5, 5 µl/ml for B. subtilis. Time-kill kinetics evaluation showed that the adducts possess bacteriostatic action. Further it was evaluated for high-throughput in vitro assays to determine the compatibility of the adducts for drug delivery. The haemolytic and thrombolytic activity was analysed against normal mouse erythrocytes. The haemolytic activity showed prominent results, and thereby projecting this acrylonitrile adducts as potent antimicrobial and haemolytic agent.


Assuntos
Acrilonitrila , Anti-Infecciosos , Animais , Camundongos , Antibacterianos/farmacologia , Antibacterianos/química , Acrilonitrila/farmacologia , Fibrinolíticos , Escherichia coli , Bactérias Gram-Negativas , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Bacillus subtilis
12.
Sci Rep ; 12(1): 11698, 2022 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-35810170

RESUMO

In this study,the water samples were collected from 31 sites of Tawang, Arunachal Pradesh, India (North-Eastern Himalaya), during the winter season to check the suitability of water for drinking and irrigation purposes.The study scientifically demonstrates the estimation of Water quality index (WQI) andhydrogeochemical characteristics of surface water samples by utilizing multivariate statistical methods. The main water quality parameters considered for this study were TDS, conductivity, salinity, pH, hardness, cations and anions. WQI was calculated in order to find out the deviation in the water quality parameters particularly with respect to BIS permissible limits.The major influencing factors responsible for the variation in these parameters were derived by using Principal component analysis (PCA) and Correlation matrix.To check the suitability of water for drinking purpose, hydrogeochemical facies and rock water interaction was derived by using well established methods such as Piper Plot (determine water type), WQI (Quality monitoring), and saturation index (for mineral dissolution). The results revealed that the silicate weathering was the main ionic source in comparison to carbonate weathering which is due to the higher dissolution capacity of silicate minerals.The results of the scattered plot between (Ca2+ + Mg2+)-(HCO3- + SO42-) versus (Na+ + K+)-Cl- (meq/L) highlighted thation exchange occurs between Mg2+ and Ca2+ofsurface water with Na+ and K+of rock /soil. This means that calcium ion was getting adsorbed, and sodium ion was getting released. The Ca2+-Mg2+-HCO3-, Na+-HCO3-and Na+-Cl- type of surface water suggested permanent and temporary hardness respectively in the studied region. The dominant cations of this study were Na+ and Ca2+ while the dominant anions were HCO3- and SO42-. In order to check the suitability of water sources for irrigation, parameters like, Magnesium hazard (MH), Total hardness (TH), Permeability Index (PI), Kelly Index (KI), Sodium adsorption rate (SAR), Sodium percentage (Na%), and Residual sodium carbonate (RSC) were determined. The results showed that 93% of the samples had PI score < 75, which indicates the suitability of the water for irrigation. Also the WQI calculation showed an average WQI value of 82.49, amongst which 61% samples were in the range of 0-50 being considered as good for drinking, while 39% were catageorised as unsuitable for drinking showing a value of > 50. Hence the above findings reveal that geogenic activities play a major role in influencing the water quality of Tawang region. Hence suitable water treatment technologies or methods might be used to eliminate thenon desirable elements and minerals present in surface water.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Cátions/análise , Monitoramento Ambiental/métodos , Água Subterrânea/análise , Índia , Minerais/análise , Sódio/análise , Poluentes Químicos da Água/análise , Qualidade da Água
13.
Heliyon ; 8(4): e09209, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35399375

RESUMO

Highly efficient and durable, silver nanoparticles doped Active Carbon Spheres ACS(Ag) were synthesized by carbonization and activation of silver exchanged resins. The silver exchanged resins were prepared by exchanging H+ ions of polystyrene sulphonate resin with Ag+ ions of silver nitrate (AgNO3). The quantity of Ag+ in the spheres was controlled by varying the concentration of AgNO3, from 0.0125 to 0.1 M. With increasing molar concentration of AgNO3, the effective intake of Ag+ by the sphere increases from 1.1 to 8.1 weight percent (wt %). For activation, the spheres were incubated in the CO2 atmosphere for 6 h at fixed soaking temperature i.e. 1123 K. The characterization of synthesized silver doped ACS was performed by using different sophisticated instrumental techniques. The antimicrobial activity of silver doped ACS was studied against different bacterial strains like, E. coli, B. subtilis and Staphylococcus aureus. The study demonstrated that the zone of inhibition for E. coli was 16.9 ± 0.7 mm while for B. subtilis it was 17.1 ± 0.3 mm at a concentration of 8 mg of synthesized material. In addition, satisfactory results were obtained in shake flask and filtration test experiments also, even at a low concentration of 2 mg, showing growth inhibition of 94% for E. coli and 93% for B. subtilis. When the concentration of silver doped ACS was increased to 8 mg, complete removal of both the bacteria was observed after 24 h (100 % reduction for E. coli and B. subtilis). Furthermore, when silver doped ACS was tested against Staphylococcus aureus according to ASTM:E 2149-01 method, biocidal activity of up to 73% was observed. Therefore, the silver doped ACS can be considered as a potential biocidal material for the studied bacterial strains and hence find suitable application for decontamination of water.

14.
J Environ Manage ; 304: 114242, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34910995

RESUMO

Novel materials with low density are being synthesized with great interest owing to their effectiveness in water purification systems. Materials of micro/nano-scale provide outstanding results in miniature point-of-use devices because of their high surface-to-volume ratio. In this study, we report the successful synthesis of hollow polymethyl methacrylate microspheres (HPM) coated with functionalized carbon nanotubes (f-CNTs) (CHPM) by employing solvent evaporation and in situ coating techniques. The surface coating of HPM with the f-CNTs was visually confirmed by the surface roughness recorded in scanning electron microscopy. Furthermore, characterization with Fourier transform infrared spectroscopy substantiated the presence of hydroxyl and carboxyl groups of f-CNTs on the CHPM. The efficiency of CHPM to remove the turbidity from surface water was evaluated. The CHPM was effective in bringing down the turbidity of the water from 500 NTU to <1 NTU (>97%) which was within the desirable limit of the Bureau of Indian Standards. The temperature and pH for maximum reduction in turbidity were optimized to 49.5 °C and 4.5, respectively. Moreover, kinetic studies of CHPM indicated that the material followed the Langmuir isotherm model with regeneration efficiency lasting more than 10 cycles. From the results, we propose a simple, facile, and cost-effective synthetic route for the synthesis of CHPM for water purification, especially for turbidity removal. The synthesized CHPM with low density and relatively large surface area offer huge potential in water treatment applications and related fields.


Assuntos
Nanotubos de Carbono , Poluentes Químicos da Água , Purificação da Água , Adsorção , Cinética , Microesferas , Polimetil Metacrilato , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Sci Total Environ ; 794: 148539, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323742

RESUMO

Digitalization provides access to an integrated network of unexploited big data with potential benefits for society and the environment. The development of smart systems connected to the internet of things can generate unique opportunities to strategically address challenges associated with the United Nations Sustainable Development Goals (SDGs) to ensure an equitable, environmentally sustainable, and healthy society. This perspective describes the opportunities that digitalization can provide towards building the sustainable society of the future. Smart technologies are envisioned as game-changing tools, whereby their integration will benefit the three essential elements of the food-water-energy nexus: (i) sustainable food production; (ii) access to clean and safe potable water; and (iii) green energy generation and usage. It then discusses the benefits of digitalization to catalyze the transition towards sustainable manufacturing practices and enhance citizens' health wellbeing by providing digital access to care, particularly for the underserved communities. Finally, the perspective englobes digitalization benefits by providing a holistic view on how it can contribute to address the serious challenges of endangered planet biodiversity and climate change.


Assuntos
Planetas , Desenvolvimento Sustentável , Mudança Climática , Objetivos , Tecnologia , Nações Unidas
16.
ACS Omega ; 6(15): 10095-10105, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-34056164

RESUMO

Smart materials with potential pH controllability are gaining widespread concern due to their versatile applicability in water purification systems. A study presented here demonstrates a successful synthesis of smart pH-responsive polyaniline (PANI)-coated hollow polymethylmethacrylate microspheres (PHPMs) using a combination of solvent evaporation and in situ coating techniques. The material was characterized by using conventional techniques. Images recorded by an optical microscope displayed clear evidence in support of the coating, which was further supported by the SEM images. Surface roughness due to the coating was distinct in the SEM images. The PANI coating has enabled the microsphere to effectively neutralize the pH of water in water purification systems, which is very important in tackling the excessive acidic or basic problem of water resources. This study introduces a simple, facile, and cost-effective synthetic route to develop polyaniline-coated hollow polymethylmethacrylate microspheres with high performance as a pH-responsive material for water purification. The low density of the material and relatively large surface area compared to conventionally used chemicals further enhance the application prospect of the material.

17.
Nanoscale Adv ; 3(20): 5722-5744, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36132675

RESUMO

Carbon nanotubes (CNTs) are considered as one of the ideal materials due to their high surface area, high aspect ratio, and impressive material properties, such as mechanical strength, and thermal and electrical conductivity, for the manufacture of next generation composite materials. In spite of the mentioned attractive features, they tend to agglomerate due to their inherent chemical structure which limits their application. Surface modification is required to overcome the agglomeration and increase their dispersability leading to enhanced interactions of the functionalized CNTs with matrix materials/polymer matrices. Recent developments concerning reliable methods for the functionalization of carbon nanotubes offer an additional thrust towards extending their application areas. By chemical functionalization, organic functional groups are generated/attached to the surfaces as well as the tip of CNTs which opens up the possibilities for tailoring the properties of nanotubes and extending their application areas. Different research efforts have been devoted towards both covalent and non-covalent functionalization for different applications. Functionalized CNTs have been used successfully for the development of high quality nanocomposites, finding wide application as chemical and biological sensors, in optoelectronics and catalysis. Non covalently functionalized carbon nanotubes have been used as a substrate for the immobilization of a large variety of biomolecules to impart specific recognition properties for the development of miniaturized biosensors as well as designing of novel bioactive nanomaterials. Functionalized CNTs have also been demonstrated as one of the promising nanomaterials for the decontamination of water due to their high adsorption capacity and specificity for various contaminants. Specifically modified CNTs have been utilized for bone tissue engineering and as a novel and versatile drug delivery vehicle. This review article discusses in short the synthesis, properties and applications of CNTs. This includes the need for functionalization of CNTs, methods and types of functionalization, and properties of functionalized CNTs and their applications especially with respect to material and biomedical sciences, water purification, and drug delivery systems.

18.
Plant Signal Behav ; 15(5): 1747689, 2020 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-32290756

RESUMO

Identifying the maximum level of inherent defense against harmful insects in natural variation among wild lineages of crop plants may result in high yield tolerant varieties and reducing use of chemical insecticides. However, knowledge of natural cotton genotypes with high insect-resistance is still indistinguishable at the biochemical or molecular level. In the present study, different cultivated Gossypium hirsutum varieties were evaluated for their inherent insect-tolerance against two major cottons chewing pests. The insect bio-assay identified two tolerant and one susceptible cotton varieties. The study demonstrates difference in phenolic acids, proanthocyanidin and tannin accumulation in tolerant and susceptible varieties. The post-infestation of chewing pests increases transcript level of the phenylpropanoid pathway genes were detected in tolerant varieties as compared to the susceptible varieties. Altogether, chewing pest-tolerance level in cotton varieties is the cumulative effect of enhanced phenylpropanoid pathway genes expression and secondary metabolite leading to defense responses to conventional host plant.


Assuntos
Gossypium/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Animais , Genótipo , Gossypium/genética , Hidroxibenzoatos/metabolismo , Mariposas/patogenicidade , Plantas Geneticamente Modificadas/genética , Proantocianidinas/metabolismo , Taninos/metabolismo
19.
J Environ Manage ; 262: 110284, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32250780

RESUMO

Sustainable agronomic practices are being implemented worldwide to promote the cleaner and planet friendly crop production. Therefore, in the present study, we investigated the effect of agro-waste derived biochar and vermicompost on soil quality and yield in Cicer arietinum L. Field experiment was carried out at three different agro-climatic regions (Varanasi, Sultanpur and Gorakhpur) of Uttar Pradesh, India and periodic soil and crop sampling were done accordingly. Experimental results proven that a significant increase (p < 0.01) in total organic carbon, available N, P and K content was observed under vermicompost followed by biochar amendment at each site. Similarly, irrespective of the experimental site, a significant increase (p < 0.01) in microbial biomass carbon was recorded under vermicompost amendment. Furthermore, the addition of vermicompost increased the grain yield (28-39%) than biochar (23-36%) addition whereas the higher microbial and soil respiration (2-6%) found in former field than the biochar added field (1-3%). Significant correlation (R2= 0.61-0.99) was found between the sustainable yield index and soil fertility factors at each site. Assessment of agricultural soil sustainability indicators (ASSI) suggests that the biochar was more effective in enhancing the soil carbon stock (21 ± 1.31 Mg C ha-1) and higher glomalin activity (62%). The study also confirmed the increased alkaline phosphatase (two fold) and ß-glucosidase activity (one fold) along with enhanced urease (45%), soil dehydrogenase activity (36%) under vermicompost amendment followed by biochar. Present study highlights the significance of sustainable agronomic practices for improving the soil quality and agricultural yield while reducing adverse impact.


Assuntos
Cicer , Solo , Agricultura , Biomassa , Carvão Vegetal , Índia
20.
Physiol Mol Biol Plants ; 26(1): 63-81, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32158121

RESUMO

In the present study the potentials of aqueous extracts of the two plants, neem (Azadirachta indica) and Tulsi (Ocimum sanctum) were examined in alleviating arsenic toxicity in rice (Oryza sativa L.) plants grown in hydroponics. Seedlings of rice grown for 8 days in nutrient solution containing 50 µM sodium arsenite showed decline in growth, reduced biomass, altered membrane permeability and increased production of superoxide anion (O2 ·-), H2O2 and hydroxyl radicals (·OH). Increased lipid peroxidation marked by elevated TBARS (thiobarbituric acid reactive substances) level, increased protein carbonylation, alterated levels of ascorbate, glutathione and increased activities of enzymes SOD (superoxide dismutase), CAT (catalase), APX (ascorbate peroxidase) and GPX (glutathione peroxidase) were noted in the seedlings on As treatment. Exogenously added leaf aqueous extracts of Azadirachta indica (0.75 mg mL-1, w/v) and Ocimum sanctum (0.87 mg mL-1, w/v) in the growth medium considerably alleviated As toxicity effects in the seedlings, marked by reduced As uptake, restoration of membrane integrity, reduced production of ROS, lowering oxidative damage and restoring the levels of ascorbate, glutathione and activity levels of antioxidative enzymes. Arsenic uptake in the seedlings declined by 72.5% in roots and 72.8% in shoots, when A. indica extract was present in the As treatment medium whereas with O. sanctum extract, the uptake declined by 67.2% in roots and 70.01% in shoots. Results suggest that both A. indica and O. sanctum aqueous extracts have potentials to alleviate arsenic toxicity in rice plants and that A. indica can serve as better As toxicity alleviator compared to O. sanctum.

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