Neoteric environmental detoxification of organic pollutants and pathogenic microbes via green synthesized ZnO nanoparticles

Nonthermal plasma processing catalyzed by CuFe2O4 for organic pollutants remediation and bacterial inactivation with density functional theory

The suggested nonthermal plasma has been employed for organic pollutants remediation and bacterial inactivation with catalyst (CuFe2O4) via reactive oxygen and nitrogen species, along with catalytic density functional theory processing. The plasma generated species O2- (g.), OH• (g.), H2O2 (aq.), and NOx (aq.) are used for the remediation of organic pollutants, such as reactive black5 and bromocresol green with catalytic oxidative and reductive transformation, like as from Fe2+ (aq.) to Fe3+ (aq.) and from Cu2+ (aq.) to Cu1+ (aq.), respectively. In the presence of plasma with CuFe2O4, the pollutants remediation enhanced more, which is 95 ± 0.78%, rather than only plasma. After removal of pollutants, the plasma processing catalyzed by CuFe2O4 was highly inactivated the E. coli. bacterial growth, which inhibition rate is 100 ± 0.87% and 100 ± 0.69% for reactive black5 and bromocresol green, rather than only plasma, such as 86.41 ± 0.91% and 73.91 ± 0.56%, respectively. The CuFe2O4 generated super oxides (O2- (aq.)) and hydroxides (H+(aq.), OH⦁(aq.), and OOH⦁(aq.)) are rapidly react with bacteria to damage the bacterial cell membrane via catalytic redox process. However, the plasma generated species were react with catalyst to produce the e- charge densities under the redox transformation of spin orientation (±) 0.58 e-, which is 0.007, 0.009, and 0.005 electrons per cubic Angstrom, for CuFe2O4, H2O2(aq.), and NOx(aq.). The plasma generated species concentrations were quantified in the deionized water, which are H2O2(aq.) (145 ± 0.91 μM) and NOx(aq.) (112 ± 0.56 μM), respectively. After eradication of pollutants, the water pH was observed, which is near to the neutral at 6.57 ± 0.27 under the catalytic binary redox process. Moreover, the catalytic stability examined via reusability test, which were four cycles for reactive black5 and three cycles for bromocresol green. Furthermore, the CuFe2O4 nanoparticles conducted several characterizations to analyze the various properties, such as crystal, surface, functional, and elemental.

Synthesis of organic-inorganic hybrid nanocomposites modified by catalase-like catalytic sites for the controlling of kiwifruit bacterial canker

Kiwifruit bacterial canker, caused by Pseudomonas syringae pv. Actinidiae (Psa), is one of the most important diseases in kiwifruit, creating huge economic losses to kiwifruit-growing countries around the world. Metal-based nanomaterials offer a promising alternative strategy to combat plant diseases induced by bacterial infection. However, it is still challenging to design highly active nanomaterials for controlling kiwifruit bacterial canker. Here, a novel multifunctional nanocomposite (ZnO@PDA-Mn) is designed that integrates the antibacterial activity of zinc oxide nanoparticles (ZnO NPs) with the plant reactive oxygen species scavenging ability of catalase (CAT) enzyme-like active sites through introducing manganese modified polydopamine (PDA) coating. The results reveal that ZnO@PDA-Mn nanocomposites can efficiently catalyze the conversion of H2O2 to O2 and H2O to achieve excellent CAT-like activity. In vitro experiments demonstrate that ZnO@PDA-Mn nanocomposites maintain the antibacterial activity of ZnO NPs and induce significant damage to bacterial cell membranes. Importantly, ZnO@PDA-Mn nanocomposites display outstanding curative and protective efficiencies of 47.7% and 53.8% at a dose of 200 μg mL-1 against Psa in vivo, which are superior to those of zinc thiozole (20.6% and 8.8%) and ZnO (38.7% and 33.8%). The nanocomposites offer improved in vivo control efficacy through direct bactericidal effects and decreasing oxidative damage in plants induced by bacterial infection. Our research underscores the potential of nanocomposites containing CAT-like active sites in plant protection, offering a promising strategy for sustainable disease management in agriculture.

A novel green preparation of zinc oxide nanoparticles with Hibiscus sabdariffa L.: photocatalytic performance, evaluation of antioxidant and antibacterial activity

This study investigates the eco-friendly synthesis of zinc oxide nanoparticles (ZnO NPs) utilizing an aqueous solution of Hibiscus sabdariffa L. flower extract, which is acts as reducing agent as well as capping agent. The Fourier transform infrared spectroscopy (FTIR) results revealed the presence of flavonoids and phenols in the plant extract, indicating that they were the major agents capable of reducing zinc nitrate salt. According to our x-ray diffraction (XRD) results, ZnO-NPs exhibit a particular phase wurtzite structure. The ZnO-NPs are spherical in shape and have an average size of 15 nm, according to the measurements of electron microscope (SEM) and transmission electron microscope (TEM) measurements. Energy dispersion (EDX) analysis demonstrates that the NPs are mainly composed of zinc and oxygen. The zeta potential of these nanoparticles shows that they are very stable. The antibacterial activity of ZnO-NPs was tested using agar dilutions with a variety of gram-positive and gram-negative microorganisms. According to the research results, ZnO-NPs can be established as an extremely specific antibacterial agent for a wide variety of organisms to prevent bacterial growth. Furthermore, the antioxidant properties of ZnO-NPs were determined using the 2,2 diphenyl-1-picrylhydrazyl hydrate (DPPH) radical scavenging approach, and the IC50 value of 38 μg/mL was measured for ZnO-NPs. Furthermore, the biosynthesized ZnO-NPs showed significant catalytic performance of methyl orange (MO) under UV irradiation. Overall, ZnO-NPs in their produced state have excellent potential in biomedical and wastewater treatment applications. Radical scavengers were used to evaluate the role of radicals in the reaction mechanism.

Thermal and biological properties of novel sodium carboxymethylcellulose-PPFMA nanocomposites containing biosynthesized Ag-ZnO hybrid filler

The aim of this study was to produce new nanocomposites with antimicrobial, antioxidant and anticancer properties that can be used in biomedical research based on carboxymethyl cellulose (NaCMC) biopolymer. First, poly(2-oxo-2-(pentafluorophenoxy)ethyl-2-methylprop-2-enoate) (PPFMA) was synthesized and characterized by FTIR and NMR techniques. It was then blended with NaCMC by in situ/hydrothermal method to produce a semi-synthetic functional material. Changes in the FTIR data of the blend and the single Tg value from DSC confirmed the compatibility of the blend. To enhance the thermal and biological properties of the NaCMC-PPFMA blend, biosynthesized Ag-ZnONPs were hydrothermally incorporated into the blend at different weight ratios. The prepared materials were characterized by SEM, EDX, TEM, XRD and FTIR. The thermal stability of the materials was determined by thermogravimetric analysis (TGA), and glass transition temperatures (Tg) was determined by differential scanning calorimeter (DSC). The oxidant, antioxidant, antimicrobial, and cytotoxic properties of PPFMA, Ag-ZnONPs, PPFMA-NaCMC blend, and nanocomposites were investigated in detail. The total oxidant state (TOS) value of the NaCMC-PPFMA blend, which was 0.72 μmol equivalent H2O2/L, increased to 7.2-10.4 μmol equivalent H2O2/L with the addition of Ag-ZnONPs. Ag-ZnONPs decreased total antioxidant state (TAS) levels of the nanocomposites while increasing their oxidant activity. Therefore, an increase in the antimicrobial activity of the nanocomposites was observed. Adding Ag-ZnONPs to the NaCMC-PPFMA blend increased the thermal stability by 22 °C and the Tg value by 9 °C. Finally, the potential of Ag-ZnONPs containing nanocomposites in wound healing therapies was examined. The findings suggest that nanocomposites prepared by incorporating Ag-ZnONPs into the semi-synthetic NaCMC-PPFMA blend can be a source of bio-safe raw materials and can be used as potential wound healers.

Development of Co3O4/TiO2/rGO photocatalyst for efficient degradation of pharmaceutical pollutants with effective charge carrier recombination suppression

Pharmaceutical contaminations in the water resources becomes very serious global environmental issue. Therefore, these pharmaceutical molecules should be removed from the water resources. In the current work, 3D/3D/2D-Co3O4/TiO2/rGO nanostructures were synthesized through a facile self-assembly-assisted solvothermal method for an effective removal of pharmaceutical contaminations. The nanocomposite was finely optimized through the response surface methodology (RSM) technique with different initial reaction parameters and different molar ratios. Various characterization techniques were used to understand the physical and chemical properties of 3D/3D/2D heterojunction and its photocatalytic performance. The degradation performance of ternary nanostructure was rapidly increased owing formation of 3D/3D/2D heterojunction nanochannels. The 2D-rGO nanosheets play an essential role in trapping photoexcited charge carriers to reduce the recombination process rapidly as confirmed by photoluminescence analysis. Tetracycline and ibuprofen were used as model carcinogen molecules to examine the degradation efficiency of Co3O4/TiO2/rGO under visible light irradiation using halogen lamp. The intermediates produced during the degradation process were studied using LC-TOF/MS analysis. The pharmaceutical molecules tetracycline and ibuprofen follows pseudo first order kinetics model. The photodegradation results show that the 6:4 M ratio of Co3O4:TiO2 with 5% rGO exhibits 12.4 times and 12.3 higher degradation ability than pristine Co3O4 nanostructures against tetracycline and ibuprofen, respectively. These results shows high efficiency of Co3O4/TiO2/rGO composite against the degradation of tetracycline and ibuprofen.

Sustainable Green Nanotechnologies for Innovative Purifications of Water: Synthesis of the Nanoparticles from Renewable Sources

Polluting the natural water resources is a serious global issue, which is confirmed by the fact that today at least 2 billion people consume water from contaminated sources. The conventional wastewater treatment methods cannot effectively remove the persistent pollutants (e.g., drugs, organic dyes, pesticides) from the aqueous environment. Heterogeneous photocatalysis is a promising and sustainable alternative for water remediation. It is based on the interaction between light irradiation and the semiconductors (e.g., TiO₂, ZnO) as photocatalysts, but these compounds, unfortunately, have some disadvantages. Hence, great attention has been paid to the nanotechnology as a possible way of improvement. Nanomaterials have extraordinary properties; however, their conventional synthesis is often difficult and requires a significant amount of dangerous chemicals. This concise topical review gives recent updates and trends in development of sustainable and green pathways in the synthesis of nanomaterials, as well as in their application for water remediation. In our review we put emphasis on the eco-friendly, mostly plant extract-based materials. The importance of this topic, including this study as well, is proved by the growing number of publications since 2018. Due to the current serious environmental issues (e.g., global warming, shortage of pure and quality water), it is necessary for the traditional TiO₂ and ZnO semiconductors to be replaced with the harmless, non-toxic, and more powerful nanocomposites as photocatalysts. Not only because of their higher efficiency as compared to the bulk semiconductors, but also because of the presence of biomolecules that can add up to the pollutant removal efficiency, which has been already confirmed in many researches. However, despite the fact that the application of heterogeneous photocatalysis together with green nanotechnology is absolutely the future in water purification, there are some challenges which have to be overcome. The exact effects of the biomolecules obtained from plants in the synthesis of nanoparticles, as well as in the photocatalytic processes, are not exactly known and require further investigation. Furthermore, heterogeneous photocatalysis is a well-known and commonly examined process; however, its practical use outside the laboratory is expensive and difficult. Thus, it has to be simplified and improved in order to be available for everyone. The aim of our review is to suggest and prove that using these bio-inspired compounds it is possible to reduce human footprint in the nature.

Graphene-based composite membranes for isotope separation: challenges and opportunities

Graphene-based membranes have got significant attention in wastewater treatment, desalination, gas separation, pervaporation, fuel cell, energy storage applications due to their supreme properties. Recently, studies have confirmed that graphene based membranes can also use for separation of isotope due to their ideal thickness, large surface area, good affinity, 2D structure etc. Herein, we review the latest groundbreaking progresses in both theoretically and experimentally chemical science and engineering of both nanoporous and lamellar graphene-based membrane for separation of different isotopes. Especially focus will be given on the current issues, engineering hurdles, and limitations of membranes designed for isotope separation. Finally, we offer our experiences on how to overcome these issues, and present an ideas for future improvement and research directions. We hope, this article is provide a timely knowledge and information to scientific communities, and those who are already working in this direction.

Unlocking the potential of biosynthesized zinc oxide nanoparticles for degradation of synthetic organic dyes as wastewater pollutants

The azo dyes released into water from different industries are accumulating in the water bodies and bioaccumulating within living systems thereby affecting environmental health. This is a major concern in developing countries where stringent regulations are not followed for the discharge of industrial waste into water bodies. This has led to the accumulation of various pollutants including dyes. As these developing countries also face acute water shortages and due to the lack of cost-effective systems to remove these pollutants, it is essential to remove these toxic dyes from water bodies, eradicate dyes, or generate fewer toxic derivatives. The photocatalysis mechanism of degradation of azo dyes has gained importance due to its eco-friendly and non-toxic roles in the environment. The zinc nanoparticles act as photocatalysts in combination with plant extracts. Plant-based nanoparticles over the years have shown the potential to degrade dyes efficiently. This is carried out by adjusting the dye and nanoparticle concentrations and combinations of nanoparticles. Our review article considers increasing the efficiency of degradation of dyes using zinc oxide (ZnO) nanoparticles and understanding the photocatalytic mechanisms in the degradation of dyes and the toxic effects of these dyes and nanoparticles in different tropic levels.

Nanomaterial-Based Antifungal Therapies to Combat Fungal Diseases Aspergillosis, Coccidioidomycosis, Mucormycosis, and Candidiasis

Over the last years, invasive infections caused by filamentous fungi have constituted a serious threat to public health worldwide. Aspergillus, Coccidioides, Mucorales (the most common filamentous fungi), and Candida auris (non-filamentous fungus) can cause infections in humans. They are able to cause critical life-threatening illnesses in immunosuppressed individuals, patients with HIV/AIDS, uncontrolled diabetes, hematological diseases, transplantation, and chemotherapy. In this review, we describe the available nanoformulations (both metallic and polymers-based nanoparticles) developed to increase efficacy and reduce the number of adverse effects after the administration of conventional antifungals. To treat aspergillosis and infections caused by Candida, multiple strategies have been used to develop new therapeutic alternatives, such as incorporating coating materials, complexes synthesized by green chemistry, or coupled with polymers. However, the therapeutic options for coccidioidomycosis and mucormycosis are limited; most of them are in the early stages of development. Therefore, more research needs to be performed to develop new therapeutic alternatives that contribute to the progress of this field.

Cr2S3(Et2DTC) complex and [Cr2S3-MoS2(Et2DTC)] bilayer thin films: single source stationed fabrication, compositional, optical, microstructural and electrochemical investigation

Current investigation has for the first time synthesized chromium sulphide diethyldithiocarbamate [Cr₂S₃(Et₂DTC)] complex utilizing diethyldithiocarbamate (DDTC) utilizing single source precursor method. Thin films of bilayer chromium sulphide diethyldithiocarmate and molybdenum disulphide [Cr₂S₃-MoS₂(Et₂DTC)] were deposited on the fluorine doped tin oxide (FTO) substrate by physical vapour deposition (PVD). Synthesized complex and bilayer were characterized by Xray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectrophotometry (UV-Vis), and scanning electron microscopy (SEM) for exploration of the compositional, optical, crystalline and morphological parameters, respectively. FT-IR peaks expressed the chelation of [Cr₂S₃(Et₂DTC)] expressing interactions between chromium sulphide and the ligand. The band gaps obtained from Tauc plot were 3.89 (direct) and 3.38 eV (indirect), respectively for Cr₂S₃(Et₂DTC) complex. The direct and indirect band gap of 3.75 and 3.35 eV, respectively, were obtained for [Cr₂S₃-MoS₂(Et₂DTC)] bilayer thin films. Average crystallite size of 13 (hexagonal orientation) and 13.4 (orthorhombic orientation) nm and for Cr₂S₃(Et₂DTC) complex and [Cr₂S₃-MoS₂(Et₂DTC)] bilayer thin films expressed from XRD. SEM micrographs expressed cannular and rod protrusions for Cr₂S₃-DDTC complex and smoother and unvarnished surficial characteristics for [Cr₂S₃-MoS₂(Et₂DTC)] bilayer thin films corresponding to compactness and uniformity of the films. Furthermore, [Cr₂S₃-MoS₂(Et₂DTC)] also expressed remarkable electrochemical aspects of the current generation and operational stability of analysed through 5760 s at 100 mA analysed via linear sweep voltammetry and chronoamperometry. The fabricated films can be efficiently used in optoelectronic devices. Current work can be extended to the optimization of bilayer thin films fabrication for achieving an alleviation in the band gaps.

Sustainability consolidation via employment of biomimetic ecomaterials with an accentuated photo-catalytic potential: emerging progressions

Environmental pollution produced due to direct and untreated release of toxic organic pollutants such as dyes from the textile industries is not only effect the human life but also contaminates the ecosystem through different transferal modes. Green nanomaterials synthesized by using biological reducing agents offer sustainable, economically viable, facile, rapid and eco-friendly approach with photocatalytic degradation efficiencies >90% for organic dyes over the other traditional technologies. Current review has for the first time comprehensively abridged the suitability of green nanoparticles over chemogenic nanoparticles, the remediative role of these biogenic nanoparticles with major emphasis on the recent progressions in the photocatalysis of different toxic dyes and pollutants. Unlike physicochemically processed nanoparticles, biogenic nanoparticles has profound contribution to the sustainable development goals due to their cleaner and economical synthesis in addition to their detoxifying role. Meticulous review of the publications are strongly suggestive of the adoptability of biogenic nanoparticles at an implementation scale for their auspicious remediative role in addition to facile fabrication, natural reducing agents based synthetic mode, toxicity free and sustainable nature. However, the studies are also indicative of the need for utilization of biogenic synthesis at practical scale to derive maximum sustainability and ecological benefits.

Innovatory role of nanomaterials as bio-tools for treatment of cancer

Conventional treatment modes like chemotherapy, thermal and radiations aimed at cancerous cells eradication are marked by destruction pointing the employment of nanomaterials as sustainable and auspicious materials for saving human lives. Cancer has been deemed as the second leading cause of death on a global scale. Nanomaterials employment in cancer treatment is based on the utilization of their inherent physicochemical characteristics in addition to their modification for using as nano-carriers and nano-vehicles eluted with anti-cancer drugs. Current work has reviewed the significant role of different types of nanomaterials in cancer therapeutics and diagnostics in a systematic way. Compilation of review has been done by analyzing voluminous investigations employing ERIC, MEDLINE, NHS Evidence and Web of Science databases. Search engines used were Google scholar, Jstore and PubMed. Current review is suggestive of the remarkable performance of nanomaterials making them candidates for cancer treatment for substitution of destructive treatment modes through investigation of their physicochemical characteristics, utilization outputs and long term impacts in patients.

Congruously designed eco-curative integrated farming model designing and employment for sustainable encompassments

Eco-degradative features associated with the modern agriculture due to utilization of toxic agro-chemicals and intensified technologies need an urgent attention. Considering this need for eco-curativeness and eco-efficiency, current has for the first time employed an integrated farming system (IFS) through designing an appropriate assemblage of vegetables, poultry, and fish (VPF) and investigated its applied scale practicability in addition to the its role in the enhancement of the productivity and environmental quality maintenance. The practical employment of VPF model resulted in the remarkable improvement of soil fertility through an increment in the essential nutrient quantity. Physicochemical analysis of the soils expressed an improvement in the treated samples, i.e., pH (7.31), EC (0.92 dS/m), organic matter (2.97%), nitrogen (2.1 mg/kg), phosphorous (120.3 mg/kg), potassium (322 mg/kg), calcium (1482.0 mg/kg), and magnesium (471.5 mg/kg). Furthermore, ecological detoxification was expressed in form of lower heavy metals (HM) in the experimental soils. At the early plantation stage, HM concentration in the soils modified with nutrient-rich water signified considerably lower pattern with trend, i.e., Cd < Zn < Ni <Pb< Cu < Fe. The morphological growth of the vegetable plants, i.e., Lycopersicon esculentum L., Capsicum annum, and Abelmoschus esculentus, and fish species, i.e., Lobeo rohita and Clarias gariepinus, in the current investigation was remarkably good. Currently employed VPF model expressed a duality in completion of sustainability goals through production of good-quality vegetables in addition to environmental integrity boosting by complete elimination of need for toxic chemical inputs. Results of this research can be adopted for large-scale employment for production of augmented agricultural production in a completely sustainable manner.

Biomimetic detoxifier Prunus cerasifera Ehrh. silver nanoparticles: innate green bullets for morbific pathogens and persistent pollutants

Silver nanoparticles were fabricated in the presence and absence of light with silver nitrate and aqueous extract of Prunus cerasifera leaf via facile and one-pot green method. P. cerasifera leaf extract reduced and stabilized the nanoparticles with phytometabolites expunging the need for addition of external reducing agents. Optimized silver nanoparticle syntheses was done with variations in leaf extract concentration, time, temperature, and molarity for deciphering the photocatalytic, antifungal, and antibacterial potential of synthesized nanoparticles. Optical, compositional, and morphological analyses of the synthesized nanoparticles were done by UV-visible spectrometry (UV-Vis), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Formation of silver nanoparticles was confirmed firstly through UV-Vis by exhibition of peaks with 400-450 nm. FTIR confirmed the presence of major organic groups responsible for reduction of nanoparticles. AFM confirmed the spherical morphology of the synthesized nanoparticles with remarkable dispersion without any agglomeration. Phytochemical analysis for P. cerasifera leaf metabolites was done by GC-MS. Spherical nanoparticles having a size range of 57-144 nm were obtained with face-centered cubic crystals. The average crystallite size obtained from XRD spectra was 2.34 nm. Enhanced photocatalytic first-order kinetics were obtained for persistent organic pollutants, i.e., crystal violet, methylene blue, and malachite green (R² = 0.99, 0.99, 0.98) in less than 15 min. Biomedical and agricultural significance as an antibiotic drug and utilization as a fungicides substitute was explored against nine resistant microbes. Statistically significant variations were analyzed via one-way analysis of variance (ANOVA) and Kruskal-Wallis test and specific multi comparison tests. Active to highly active inhibition zones manifested the use of biogenic silver nanoparticles as potential candidate for applications in biological arenas and as environmental remediators.

Impact of nanomaterials on ecosystems: Mechanistic aspects in vivo

Nanotechnologies are becoming increasingly popular in modern era of human development in every aspect of life. Their impact on our ecosystem in air, soil, and water is largely unknown because of the limited amount of information available, and hence, they require considerable attention. This account highlights the important routes of nanomaterials toxicity in air, soil, and water, their possible impact on the ecosystem and aquatic life. The mechanistic aspects have been focused on the size, shape, and surface modifications of nanomaterials. The preventive measures and future directions along with appropriate designs and implementation of nanotechnologies have been proposed so as to minimize the interactions of nanomaterials with terrestrial flora and aquatic life. Specifically, the focus largely remains on the toxicity of metallic nanoparticles such as gold (Au) and silver (Ag) because of their applications in diverse fields. The account lists some prominent mechanistic routes of nanotoxicity along with in vivo experimental results based on the fundamental understanding that how nanometallic surfaces interact with plant as well as animal biological systems. The appropriate modifications of the nanometallic surfaces with biocompatible molecules are considered to be the most effective preventive measures to reduce the nanotoxicity.

Removal of Banana Tree Fungi Using Green Tuff Rock Powder Waste Containing Zeolite

Hinai green tuff, which is found in Akita Prefecture, Japan, is used for the production of building materials, etc. About 60% of all stone is emitted as waste powder and therefore it is important to find ways for recycling it. In this work, the characteristics of green tuff powder have been investigated. The results of scanning electron microscope (SEM) and elemental map observations indicate that the green tuff contains TiO2 on zeolite. The green tuff can therefore be used as a natural catalyst for producing hydrogen peroxide with moisture and oxygen with light. The optimum calcined temperature of the green tuff powder is about 800 °C, producing the hydroxyl radical from hydrogen peroxide decomposition without ultraviolet light (UV) and decomposition of the superoxide anion. As the application of green tuff powder, Cavendish banana trees found in the Philippines infected by a new Panama disease were treated with powder suspension in order to remove the fungus (a type of Fusarium wilt) due to the photocatalyst characteristics of powder. The suspension, prepared by using the powder was sprayed on the infected banana trees for about one month. Photograph observation indicated that the so-called 800 °C suspension spray was more effective in growing the infected banana trees.