g-C3N4@CuO electrostatic self-assembly toward Ralstonia solanacearum: Insights from cytomembrane and motility disruption

BACKGROUND

Ralstonia solanacearum, a notorious and refractory bacterial plant pathogen, threatens multiple vegetable crops and causes significant economic loss in agriculture. Long-term use of traditional medicines not only increases the problem of drug resistance, but also causes great environmental pollution. Therefore, there is an urgent need to develop new agents with high efficacy and low toxicity.

RESULTS

In this study, we have synthesized and characterized graphitic carbon nitride incorporated copper oxide composite (g-C3N4@CuO), which showed higher antimicrobial effect than graphitic carbon nitride nanosheets (g-C3N4 nanosheets) and copper oxide nanoparticles (CuONPs). Ralstonia solanacearum exposed to g-C3N4@CuO exhibited higher levels of oxygen toxicity, cell membrane damage, DNA damage, motility disruption and even cell death compared to g-C3N4 nanosheets and CuONPs. In addition, g-C3N4@CuO was more effective in the control of tobacco bacterial wilt than g-C3N4 nanosheets and CuONPs.

CONCLUSION

Thus, this study provides a new perspective on g-C3N4@CuO control of bacterial diseases in crops, and the mechanism is related to the destruction of cell membrane damage and motility disruption. © 2024 Society of Chemical Industry.

Multi-functional copper oxide nanoparticles synthesized using Lagerstroemia indica leaf extracts and their applications

Developing multifunctional nanomaterials through environmentally friendly and efficient approaches is a pivotal focus in nanotechnology. This study aimed to employ a biogenic method to synthesize multifunctional copper oxide nanoparticles (LI-CuO NPs) with diverse capabilities, including antibacterial, antioxidant, and seed priming properties, as well as photocatalytic organic dye degradation and wastewater treatment potentials using Lagerstroemia indica leaf extract. The synthesized LI-CuO NPs were extensively characterized using UV-vis spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform-infrared spectroscopy (FT-IR). The colloid displayed surface plasmon resonance peaks at 320 nm, characteristic of LI-CuO NPs. DLS analysis revealed an average particle size of 93.5 nm and a negative zeta potential of -20.3 mV. FTIR and XPS analyses demonstrated that LI-CuO NPs possessed abundant functional groups that acted as stabilizing agents. XRD analysis indicated pure crystalline and spherical LI-CuO NPs measuring 36 nm in size. Antibacterial tests exhibited significant differential activity of LI-CuO NPs against both gram-negative (Escherichia coli, Salmonella typhimurium) and gram-positive (Staphylococcus aureus and Listeria monocytogenes) bacteria. In antioxidant tests, the LI-CuO NPs demonstrated a remarkable radical scavenging activity of 97.6 % at a concentration of 400 μg mL-1. These nanoparticles were also found to enhance mustard seed germination at low concentrations. With a remarkable reusability, LI-CuO NPs exhibited excellent photocatalytic performance, with a degradation efficiency of 97.6 % at 150 μg/mL as well as a 95.6 % reduction in turbidity when applied to wastewater treatment. In conclusion, this study presents environmentally friendly method for the facile synthesis of LI-CuO NPs that could potentially offer promising applications in biomedicine, agriculture, and environmental remediation due to their multifunctional properties.

Benign-by-design plant extract-mediated preparation of copper oxide nanoparticles for environmentally related applications

A facile, cost-competitive, scalable and novel synthetic approach is used to prepare copper oxide (CuO) nanoparticles (NPs) using Betel leaf (Piper betle) extracts as reducing, capping, and stabilizing agents. CuO-NPs were characterized using various analytical techniques, including Fourier-transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), as well as photoluminescence (PL) measurements. The activity of CuO-NPs was investigated towards Congo red dye degradation, supercapacitor energy storage and antibacterial activity. A maximum of 89% photodegradation of Congo red dye (CR) was obtained. The nanoparticle modified electrode also exhibited a specific capacitance (Csp) of 179 Fg-1. Furthermore, the antibacterial potential of CuO NPs was evaluated against Bacillus subtilis and Pseudomonas aeruginosa, both strains displaying high antibacterial performance.

Biomedical behaviors of CuO/γ-alumina/chitosan nanocomposites: Scolicidal and apoptotic effects on hydatid cysts protoscolices

Hydatid cysts caused by Echinococcus granulosus are a serious health problem that requires effective treatment. This study aimed to evaluate the scolicidal and apoptotic effects of copper oxide (CuO) and gamma alumina (γ-Al2O3) with or without chitosan (Chit), using Rosmarinus officinalis extract and chemical methods on protoscolices (PSCs) in vitro. The nanomaterials (NMs) were characterized by FTIR, EDS, DLS, XRD, FESEM, PDI, and zeta potential (ZP). Scolicidal and apoptotic effects of NMs were tested against PSCs at different concentrations and exposure times. The CuO NPs showed the highest scolicidal effect (33.26 %) among all NMs at 1.6 mg/mL and 60 min, followed by phytosynthesized CuO/γ-Al2O3 NC (23.41 %). The chitosan-modified CuO/γ-Al2O3 NC and the chemically synthesized CuO/γ-Al2O3 NC had less effect. The CuO NPs and the phytosynthesized CuO/γ-Al2O3 NC also significantly increased the expression of the caspase-3 gene in the PSCs at 0.4 mg/mL, indicating the induction of apoptosis. In conclusion, this study suggests that the phytosynthesized CuO/γ-Al2O3 NC and the CuO NPs could be potential candidates for treating echinococcosis by killing the PSCs through apoptosis. Further studies are needed to verify the in vivo efficacy and toxicity of these NMs and to optimize their delivery and targeting systems.

Phytogenic nanoparticles: synthesis, characterization, and their roles in physiology and biochemistry of plants

Researchers are swarming to nanotechnology because of its potentially game-changing applications in medicine, pharmaceuticals, and agriculture. This fast-growing, cutting-edge technology is trying different approaches for synthesizing nanoparticles of specific sizes and shapes. Nanoparticles (NPs) have been successfully synthesized using physical and chemical processes; there is an urgent demand to establish environmentally acceptable and sustainable ways for their synthesis. The green approach of nanoparticle synthesis has emerged as a simple, economical, sustainable, and eco-friendly method. In particular, phytoassisted plant extract synthesis is easy, reliable, and expeditious. Diverse phytochemicals present in the extract of various plant organs such as root, leaf, and flower are used as a source of reducing as well as stabilizing agents during production. Green synthesis is based on principles like prevention/minimization of waste, reduction of derivatives/pollution, and the use of safer (or non-toxic) solvent/auxiliaries as well as renewable feedstock. Being free of harsh operating conditions (high temperature and pressure), hazardous chemicals and the addition of external stabilizing or capping agents makes the nanoparticles produced using green synthesis methods particularly desirable. Different metallic nanomaterials are produced using phytoassisted synthesis methods, such as silver, zinc, gold, copper, titanium, magnesium, and silicon. Due to significant differences in physical and chemical properties between nanoparticles and their micro/macro counterparts, their characterization becomes essential. Various microscopic and spectroscopic techniques have been employed for conformational details of nanoparticles, like shape, size, dispersity, homogeneity, surface structure, and inter-particle interactions. UV-visible spectroscopy is used to examine the optical properties of NPs in solution. XRD analysis confirms the purity and phase of NPs and provides information about crystal size and symmetry. AFM, SEM, and TEM are employed for analyzing the morphological structure and particle size of NPs. The nature and kind of functional groups or bioactive compounds that might account for the reduction and stabilization of NPs are detected by FTIR analysis. The elemental composition of synthesized NPs is determined using EDS analysis. Nanoparticles synthesized by green methods have broad applications and serve as antibacterial and antifungal agents. Various metal and metal oxide NPs such as Silver (Ag), copper (Cu), gold (Au), silicon dioxide (SiO2), zinc oxide (ZnO), titanium dioxide (TiO2), copper oxide (CuO), etc. have been proven to have a positive effect on plant growth and development. They play a potentially important role in the germination of seeds, plant growth, flowering, photosynthesis, and plant yield. The present review highlights the pathways of phytosynthesis of nanoparticles, various techniques used for their characterization, and their possible roles in the physiology of plants.

Green synthetized Cu-Oxide Nanoparticles: Properties and applications for enhancing healing of wounds infected with Staphylococcus aureus

Treating wound infections is a challenging concern in various clinical settings in Egypt, especially in the increasing global problem of resistance to antimicrobials. Here, we aimed to fabricate CuO NPs via green synthesis using aqueous Yucca gigantea extract. Then, the effect of green synthesized CuO NPs on Staphylococcus aureus clinical isolates has been studied in vivo and in vitro. The aqueous extract of Yucca gigantea has been employed in our study as a scale-up approach to safely, affordably, sustainably, and practically fabricate copper oxide nanoparticles (CuO NPs). Fourier transforms infrared (FT-IR), X-ray Diffraction (XRD), and UV-vis spectroscopy were utilized in vitro to describe the bonding features of CuO NPs.Scanning Electron microscopy (SEM), Transmission electron microscopy (TEM), Energy dispersive X-ray (EDX), and dynamic light scattering (DLS) were used to detect the morphological and elemental composition of the resulting CuO NPs. The fabrication of CuO NPs was confirmed by the IR spectral band at 515 cm-1, ensuring the metal-oxygen bondCu-O with two strong bands at 229 and 305 nm. SEM and TEM show CuO NPs with a size range from 30 to 50 nm. Cu and O comprised most of the particles produced through green synthesis, with weight percentages of 57.82 and 42.18 %, respectively. CuO NPs were observed to have a Zeta-potential value of -15.7 mV, demonstrating their great stability. CuO NPs revealed antibacterial potential toward the tested isolates with minimum inhibitory concentration values of 128 to 512 µg/mL. CuO NPs had antibiofilm potential by crystal violet assay, downregulating the expression of icaA and icaD genes in 23.07 % and 19.32 of the S. aureus isolates. The wound-healing potential of CuO NPs was investigated in vivo. It significantly decreased the bacterial burden and increased wound healing percentage compared to the positive control group. Moreover, CuO NPs caused an upregulation of the genes encoding platelet-derived growth factor (PDGF) and fibronectin in tissue repair. Thus, we can use CuO NPs as a future source for wound healing materials, especially in infected wounds.

Green synthesis of copper oxide nanoparticles and its efficiency in degradation of rifampicin antibiotic

In recent ages, green nanotechnology has gained attraction in the synthesis of metallic nanoparticles due to their cost-effectiveness, simple preparation steps, and environmentally-friendly. In the present study, copper oxide nanoparticles (CuO NPs) were prepared using Parthenium hysterophorus whole plant aqueous extract as a reducing, stabilizing, and capping agent. The CuO NPs were characterized via UV-Vis Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), powder X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS). The UV-Vis spectra of CuO NPs showed a surface plasmonic resonance band to occur at 340 nm. FTIR analysis revealed the presence of secondary metabolites on the surface of CuO NPs, with a characteristic Cu-O stretching band being identified at 522 cm-1. Scanning electron micrographs and transmission electron micrographs showed that CuO NPs were nearly spherical, with an average particle of 59.99 nm obtained from the SEM micrograph. The monoclinic crystalline structure of CuO NPs was confirmed using XRD, and crystallite size calculated using the Scherrer-Debye equation was found to be 31.58 nm. DLS showed the presence of nanoparticle agglomeration, which revealed uniformity of the CuO NPs. Furthermore, the degradation ability of biosynthesized nanoparticles was investigated against rifampicin antibiotic. The results showed that the optimum degradation efficiency of rifampicin at 98.43% was obtained at 65℃ temperature, 50 mg dosage of CuO NPs, 10 mg/L concentration of rifampicin solution, and rifampicin solution at pH 2 in 8 min. From this study, it can be concluded that CuO NPs synthesized from Parthenium hysterophorus aqueous extract are promising in the remediation of environmental pollution from antibiotics. In this light, the study reports that Parthenium hysterophorus-mediated green synthesis of CuO NPs can effectively address environmental pollution in cost-effective, eco-friendly, and sustainable ways.

Hippophae rhamnoides L. (sea buckthorn) mediated green synthesis of copper nanoparticles and their application in anticancer activity

Green synthesis of nanoparticles has drawn huge attention in the last decade due to their eco-friendly, biocompatible nature. Phyto-assisted synthesis of metallic nanoparticles is widespread in the field of nanomedicine, especially for antimicrobial and anticancer activity. Here in the present research work, investigators have used the stem extract of the Himalayan plant Hippophae rhamnoides L, for the synthesis of copper nanoparticles (CuNPs). The synthesized of CuNPs were analyzed by using sophisticated instruments, i.e., Fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, X-ray diffraction (XRD), high-performance liquid chromatography (HPLC), and scanning electron microscope (SEM). The size of the synthesized CuNPs was varying from 38 nm to 94 nm which were mainly spherical in shape. Further, the potential of the synthesized CuNPs was evaluated as an anticancer agent on the Hela cell lines, by performing an MTT assay. In the MTT assay, a concentration-dependent activity of CuNPs demonstrated the lower cell viability at 100 μg/mL and IC50 value at 48 μg/mL of HeLa cancer cell lines. In addition to this, apoptosis activity was evaluated by reactive oxygen species (ROS), DAPI (4',6-diamidino-2-phenylindole) staining, Annexin V, and Propidium iodide (PI) staining, wherein the maximum ROS production was at a dose of 100 µg per mL of CuNPs with a higher intensity of green fluorescence. In both DAPI and PI staining, maximum nuclear condensation was observed with 100 μg/mL of CuNPs against HeLa cell lines.

Applications of drug delivery systems, organic, and inorganic nanomaterials in wound healing

The skin is known to be the largest organ in the human body, while also being exposed to environmental elements. This indicates that skin is highly susceptible to physical infliction, as well as damage resulting from medical conditions such as obesity and diabetes. The wound management costs in hospitals and clinics are expected to rise globally over the coming years, which provides pressure for more wound healing aids readily available in the market. Recently, nanomaterials have been gaining traction for their potential applications in various fields, including wound healing. Here, we discuss various inorganic nanoparticles such as silver, titanium dioxide, copper oxide, cerium oxide, MXenes, PLGA, PEG, and silica nanoparticles with their respective roles in improving wound healing progression. In addition, organic nanomaterials for wound healing such as collagen, chitosan, curcumin, dendrimers, graphene and its derivative graphene oxide were also further discussed. Various forms of nanoparticle drug delivery systems like nanohydrogels, nanoliposomes, nanofilms, and nanoemulsions were discussed in their function to deliver therapeutic agents to wound sites in a controlled manner.

Biogenic Synthesis of Copper Nanoparticles: A Systematic Review of Their Features and Main Applications

Nanotechnology is an innovative field of study that has made significant progress due to its potential versatility and wide range of applications, precisely because of the development of metal nanoparticles such as copper. Nanoparticles are bodies composed of a nanometric cluster of atoms (1-100 nm). Biogenic alternatives have replaced their chemical synthesis due to their environmental friendliness, dependability, sustainability, and low energy demand. This ecofriendly option has medical, pharmaceutical, food, and agricultural applications. When compared to their chemical counterparts, using biological agents, such as micro-organisms and plant extracts, as reducing and stabilizing agents has shown viability and acceptance. Therefore, it is a feasible alternative for rapid synthesis and scaling-up processes. Several research articles on the biogenic synthesis of copper nanoparticles have been published over the past decade. Still, none provided an organized, comprehensive overview of their properties and potential applications. Thus, this systematic review aims to assess research articles published over the past decade regarding the antioxidant, antitumor, antimicrobial, dye removal, and catalytic activities of biogenically synthesized copper nanoparticles using the scientific methodology of big data analytics. Plant extract and micro-organisms (bacteria and fungi) are addressed as biological agents. We intend to assist the scientific community in comprehending and locating helpful information for future research or application development.

Green synthesis of CuO nanoparticles using Hibiscus sabdariffa L. extract to treat wastewater in Soba Sewage Treatment Plant, Sudan

Looking for a cost-effective and ecofriendly method for wastewater treatment is a global challenge. Therefore, this study investigated the removal of wastewater pollutants using copper oxide nanoparticles (CuONPs). CuONPs synthesized by a green solution combustion synthesis (SCS) and characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared (FT-IR), powder X-ray diffraction analysis (PXRD), and scanning electron microscopy (SEM) techniques. PXRD showed nanoparticle sizes ranging from 10 to 20 polycrystalline patterns indexed with two peaks corresponding to (111) and (113) reflections of the face-centered cubic CuO crystal. The energy-dispersive spectroscopy analysis obtained in conjunction with SEM analysis proved the presence of Cu and O atoms at 86.3 and 13.6%, respectively, confirming the reduction and capping of Cu with Hibiscus sabdariffa extract's phytochemicals. The CuONPs proved to be a promising decontaminant for wastewater found to reduce biochemical oxygen demand (BOD) and chemical oxygen demand (COD) by 56%, and very efficient in reducing both the total dissolved matter (TDS) and conductivity (σ) by 99%. The CuONPs removed simultaneously chromium, copper, and chloride with respective percentages of 26, 78.8, and 78.2%. Green synthesis of nanoparticles is a simple, rapid, cost-effective, and ecofriendly method that successfully removed contaminants from wastewater.

Removal of hydrocarbons and heavy metals from petroleum water by modern green nanotechnology methods

Considered heavy metals, such as As(III), Bi(II), Cd(II), Cr(VI), Mn(II), Mo(II), Ni(II), Pb(II), Sb(III), Se(-II), Zn(II), and contaminating chemical compounds (monocyclic aromatic hydrocarbons such as phenolic or polycyclic derivatives) in wastewater (petrochemical industries: oil and gas production plants) are currently a major concern in environmental toxicology due to their toxic effects on aquatic and terrestrial life. In order to maintain biodiversity, hydrosphere ecosystems, and people, it is crucial to remove these heavy metals and polluting chemical compounds from the watery environment. In this study, different Nanoparticles (α-Fe₂O₃, CuO, and ZnO) were synthesized by green synthesis method using Portulaca oleracea leaf extract and characterized by UV-Vis spectrophotometers, FTIR spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) techniques in order to investigate morphology, composition, and crystalline structure of NPs, these were then used as adsorbent for the removal of As(III), Bi(II), Cd(II), Cr(VI), Mn(II), Mo(II), Ni(II), Pb(II), Sb(III), Se(-II), and Zn(II) from wastewater, and removal efficiencies of were obtained 100% under optimal conditions.

Antimicrobial, antioxidant, and cytotoxic properties of biosynthesized copper oxide nanoparticles (CuO-NPs) using Athrixia phylicoides DC

Nanoparticles produced from various metal elements including copper have been used in the treatment of infectious diseases in response to antibiotic failure due to microbial resistance. Copper is recommended for use in the production of nanoparticles largely because of its accessibility and affordability. This study aimed to synthesise copper oxide nanoparticles (CuO-NPs) using leaf extracts of Athrixia phylicoides and assess their antibacterial, antioxidant and cytotoxicity properties. The characterization of the obtained NPs was done through X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Energy-dispersive spectroscopy (EDS). Our results showed that the NPs had a highly crystalline, quasi-spherical shape with an average diameter of 42 nm. Also, gram-positive bacteria Bacillus cereus and Staphylococcus aureus were the most susceptible to CuO-NPs with MIC values of 0.62 mg/mL and 0.16 mg/mL, respectively, as shown by the broth microdilution method. In addition, CuO-NPs demonstrated strong radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibitory activity with an IC₅₀ value of 10.68 ± 0.03 μg/mL. However, the cytotoxicity activity determined by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) (MTT) assay revealed that the CuO-NPs were not toxic to human embryonic kidney cells (HEK 293 cells) at an LC₅₀ value of 66.08 ± 0.55 μg/mL. The synthesised CuO-NPs showed high antibacterial, and antioxidant potency and less toxicity. Therefore, they could be a feasible alternative source of therapeutic agents in treating bacterial and oxidative stress-induced diseases.

Role of nanohybrid NiO–Fe3O4 in enhancing the adsorptive performance of activated carbon synthesized from Yemeni-Khat leave in removal of Pb (II) and Hg (II) from aquatic systems

Over years, existence of toxic chemical heavy metal in aquatic systems has motivated more research studies toward the preparation of effective stable solid adsorbents for the removal of toxic chemical pollutants. Therefore, in the current research study, activated carbon adsorbent (AC) was synthesized from Yemeni khat (catha edulis) leaves which are considered as waste accumulated on waste disposal areas in Yemen. KOH (2.0 N) was used as a chemical activator to produce the AC material which was subsequently heated at 400 °C. A simple co-precipitation method was used to chemically modify AC with varying weight ratios of NiO-Fe₃O₄ NPs (5, 15, and 25 wt %). The modified AC was used to remove toxic Pb(II) and Hg(II) ions from aquatic systems. Numerous techniques, which included x-ray diffraction (XRD), Fourier transforms infrared (FTIR), field emission scanning electron microscope (FE-SEM), and N₂ adsorption/desorption isotherms, were used to confirm the morphology of AC and 5, 15, and 25 wt% NiO-Fe₃O₄/AC samples. The study findings demonstrated that, NiO-Fe₃O₄ nanoparticles improved the adsorption efficiency for toxic Pb(II) and Hg (II) ions. The AC adsorbent attained maximum removal efficiencies of 88.95% and 87.56% for Pb (II) and Hg (II) ions, respectively. In contrast, 15-NF/AC NC sample successfully attained the highest removal efficiencies of 100% for pb(II) and 99.71% for Hg(II). According to the experimental findings, the prepared NF/AC adsorbents were effective and they can be used as inexpensive and stable solid nanoadsorbents in water treatment.

Synthesis, biomedical applications, and toxicity of CuO nanoparticles

Versatile nature of copper oxide nanoparticles (CuO NPs) has made them an imperative nanomaterial being employed in nanomedicine. Various physical, chemical, and biological methodologies are in use for the preparation of CuO NPs. The physicochemical and biological properties of CuO NPs are primarily affected by their method of fabrication; therefore, selectivity of a synthetic technique is immensely important that makes these NPs appropriate for a specific biomedical application. The deliberate use of CuO NPs in biomedicine questions their biocompatible nature. For this reason, the present review has been designed to focus on the approaches employed for the synthesis of CuO NPs; their biomedical applications highlighting antimicrobial, anticancer, and antioxidant studies; and most importantly, the in vitro and in vivo toxicity associated with these NPs. This comprehensive overview of CuO NPs is unique and novel as it emphasizes on biomedical applications of CuO NPs along with its toxicological assessments which would be useful in providing core knowledge to researchers working in these domains for planning and conducting futuristic studies. KEY POINTS: • The recent methods for fabrication of CuO nanoparticles have been discussed with emphasis on green synthesis methods for different biomedical approaches. • Antibacterial, antioxidant, anticancer, antiparasitic, antidiabetic, and antiviral properties of CuO nanoparticles have been explained. • In vitro and in vivo toxicological studies of CuO nanoparticles exploited along with their respective mechanisms.

Biosynthesized metal oxide nanoparticles for sustainable agriculture: next-generation nanotechnology for crop production, protection and management

The current agricultural sector is not only in its most vulnerable state but is also becoming a threat to our environment due to expanding population and growing food demands along with worsening climatic conditions. In addition, numerous agrochemicals presently being used as fertilizers and pesticides have low efficiency and high toxicity. However, the rapid growth of nanotechnology has shown great promise to tackle these issues replacing conventional agriculture industries. Since the last decade, nanomaterials especially metal oxide nanoparticles (MONPs) have been attractive for improving agricultural outcomes due to their large surface area, higher chemical/thermal stability and tunable unique physicochemical characteristics. Further, to achieve sustainability, researchers have been extensively working on ecological and cost-effective biological approaches to synthesize MONPs. Hereby, we have elaborated on recent successful biosynthesis methods using various plants/microbes. Furthermore, we have elucidated different mechanisms for the interaction of MONPs with plants, including their uptake/translocation/internalization, photosynthesis, antioxidant activity, and gene alteration, which could revolutionize crop productivity/yield through increased nutrient amount, photosynthesis rate, antioxidative enzyme level, and gene upregulations. Besides, we have briefly discussed about functionalization of MONPs and their application in agricultural-waste-management. We have further illuminated recent developments of various MONPs (Fe₂O₃/ZnO/CuO/Al₂O₃/TiO₂/MnO₂) as nanofertilizers, nanopesticides and antimicrobial agents and their implications for enhanced plant growth and pest/disease management. Moreover, the potential use of MONPs as nanobiosensors for detecting nutrients/pathogens/toxins and safeguarding plant/soil health is also illuminated. Overall, this review attempts to provide a clear insight into the latest advances in biosynthesized MONPs for sustainable crop production, protection and management and their scope in the upcoming future of eco-friendly agricultural nanotechnology.

Modulation of Gut Microbiota by Essential Oils and Inorganic Nanoparticles: Impact in Nutrition and Health

Microbiota plays a crucial role in human health and disease; therefore, the modulation of this complex and yet widely unexplored ecosystem is a biomedical priority. Numerous antibacterial alternatives have been developed in recent years, imposed by the huge problem of antibioresistance, but also by the people demand for natural therapeutical products without side effects, as dysbiosis, cyto/hepatotoxicity. Current studies are focusing mainly in the development of nanoparticles (NPs) functionalized with herbal and fruit essential oils (EOs) to fight resistant pathogens. This is due to their increased efficiency against susceptible, multidrug resistant and biofilm embedded microorganisms. They are also studied because of their versatile properties, size and possibility to ensure a targeted administration and a controlled release of bioactive substances. Accordingly, an increasing number of studies addressing the effects of functional nanoparticles and plant products on microbial pathogens has been observed. Regardless the beneficial role of EOs and NPs in the treatment of infectious diseases, concerns regarding their potential activity against human microbiota raised constantly in recent years. The main focus of current research is on gut microbiota (GM) due to well documented metabolic and immunological functions of gut microbes. Moreover, GM is constantly exposed to micro- and nano-particles, but also plant products (including EOs). Because of the great diversity of both microbiota and chemical antimicrobial alternatives (i.e., nanomaterials and EOs), here we limit our discussion on the interactions of gut microbiota, inorganic NPs and EOs. Impact of accidental exposure caused by ingestion of day care products, foods, atmospheric particles and drugs containing nanoparticles and/or fruit EOs on gut dysbiosis and associated diseases is also dissected in this paper. Current models developed to investigate mechanisms of dysbiosis after exposure to NPs/EOs and perspectives for identifying factors driving EOs functionalized NPs dysbiosis are reviewed.

Assessment of molluscicidal and larvicidal activities of CuO nanoparticles on Biomphalaria alexandrina snails

Background

Schistosomiasis is a major, but generally overlooked, tropical disease carried by snails of the genus Biomphalaria, which have a large distribution in Egypt. Control of the intermediate host snail is critical in limiting schistosomiasis spread. On the topic of snails’ management, nanotechnology has gained more interest.

Results

Copper oxide nanoparticles, characterised by transmission electron microscopy and X-ray diffraction, showed a single crystal structure with an average crystallite size around 40 nm by X-ray diffraction and typical transmission electron microscopy (TEM) image. Also, the UV–VIS spectrophotometer displayed a sharp absorption band of CuO NPs. Molluscicidal activity of copper oxide nanoparticles against B. alexandrina snails was observed. Following exposure to CuO NPs (LC50 and LC90 was 40 and 64.3 mg/l, respectively), there was a reduction in the growth and reproductive rates of treated B. alexandrina at the sub-lethal concentrations, as well as, a drop in egg viability. Moreover, CuO NPs exhibited a toxic effect on miracidiae and cercariae of S. mansoni. Scanning electron microscopy (SEM) investigations of the head-foot and mantle of control and treated snails to the sub-lethal concentrations of CuO NPs (LC10 15.6 mg\l–LC25 27.18 mg\l) indicated morphological alterations in the ultrastructure.

Conclusions

CuO NPs caused a significant effect against the intermediate hosts of S. mansoni and provide a considerable scope in exploiting local indigenous resources as snail molluscicidal agents.

Role of Nanobiotechnology Towards Agri-Food System

The major challenge of modern agriculture is to satisfy actual and future global food demands efficiently. This great challenge requires combined efforts to preserve natural resources to support intensive agriculture while limiting detrimental impacts on the environment. One of these efforts is using nanobiotechnology. Nanobiotechnology is the application of nanotechnology in biological science. Nanotechnology is the science of manipulating materials at the nanoscale (1 nm = 10ˉ⁹ m). This review summarizes the potential of nanobiotechnology for its importance in increasing yield in agriculture and providing consumers with quality and contamination-free food. In the agriculture sector, nanobiotechnology is necessarily used as fertilizers (nanofertilizers) for crop yield improvement, pesticides (nanopesticides) for crop protection, and nanobiosensors for the detection of crop pathogens, soil conditions, and vegetation conditions, Similarly, intelligent food packaging, and detection of pathogens, adulterants, and toxins in food are its importance in the food sector.

Green Synthesis and Pinning Behavior of Fe-Doped CuO/Cu2O/Cu4O3 Nanocomposites

Egg white-induced auto combustion has been used to synthesize undoped and Fe-doped CuO/Cu2O/Cu4O3 nanocomposites in a soft, secure, and one-pot procedure. X-ray powder diffraction (XRD) and Fourier transform infrared (FTIR) investigations have been used to identify functional groups and the structural properties of crystalline phases present in the as-synthesized composites. Scanning Electron Microscopy/Energy Dispersive Spectrometry (SEM/EDS) elemental mapping analyses and Transmission Electron Microscopy (TEM) techniques were used to explore the morphological and compositional properties of these composites. N2- adsorption/desorption isotherm models have been used to examine the surface variables of the as-prepared systems. Based on the Vibrating Sample Magnetometer (VSM) technique, the magnetic properties of various copper-based nanocomposites were detected due to being Fe-doped. XRD results showed that the undoped system was composed of CuO as a major phase with Cu2O and Cu4O3 as second phases that gradually disappeared by increasing the dopant content. The crystalline phase’s crystallographic properties were determined. The average particle size was reduced when the synthesized systems were doped with Fe. The construction of porous and polycrystalline nanocomposites involving Cu, Fe, O, and C components was confirmed by SEM/EDS and TEM measurements. In terms of the increase in magnetization of the as-manufactured nanocomposites due to Fe-doping, oxygen vacancies at the surface/or interfacial of nanoparticles, while also domain wall pinning mechanisms, were investigated. Finally, employing the investigated production process, Fe doping of CuO/Cu2O/Cu4O3 nanocomposite resulted in the development of a single phase (CuO) exhibiting “pinned” type magnetization. This is the first publication to show that CuO/Cu2O/Cu4O3.

Phyto-Mediated Copper Oxide Nanoparticles for Antibacterial, Antioxidant and Photocatalytic Performances

The greatest challenge of the current generation and generations to come is antimicrobial resistance, as different pathogenic bacteria have continuously evolved to become resistant to even the most recently synthesized antibiotics such as carbapenems. Resistance to carbapenems limits the therapeutic options of MDR infections as they are the only safe and effective drugs recommended to treat such infections. This scenario has complicated treatment outcomes, even to the commonest bacterial infections. Repeated attempts to develop other approaches have been made. The most promising novel therapeutic option is the use of nanomaterials as antimicrobial agents. Thus, this study examined the efficacy of Camellia sinensis extract (CSE) and Prunus africana bark extract (PAE) green synthesized Copper oxide nanoparticles (CuONPs) against carbapenem-resistant bacteria. Furthermore, the photocatalytic and antioxidant activities of CuONPs were evaluated to determine the potential of using them in a wide range of applications. CuONPs were biosynthesized by CSE and PAE. UV vis spectroscopy, X-ray Diffraction (XRD), Dynamic light scattering (DLS), Fourier Transform Infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) were used to characterize the nanoparticles. CuONPs susceptibility tests were carried out by the agar well diffusion method. The photocatalytic and antioxidant activities of the CuONPs were determined by the methylene blue and DPPH free radical scavenging assays, respectively. UV vis absorbance spectra registered surface plasmon resonance peaks between 272 and 286 nm, confirming the presence of CuONPs. The XRD array had nine strong peaks at 2θ values typical of CuONPs. FTIR spectra exhibited bands associated with organic functional groups confirming capping and functionalization of the CuONPs by the phytochemicals. DLS analysis registered a net zeta potential of +12.5 mV. SEM analysis revealed that the nanoparticles were spherical and clustered with a mean diameter of 6 nm. Phytosynthesized CuONPs exhibited the highest growth suppression zones of 30 mm with MIC ranging from 30 to 125 μg/ml against MDR bacteria. Furthermore, the CuONPs achieved a methylene blue dye photocatalysis degradation efficiency of 85.5% and a free radical scavenging activity of 28.8%. PAE and CSE successfully bio-reduced copper ions to the nanoscale level with potent antimicrobial, photocatalysis, and antioxidant activities.

Gold dispersed hierarchical flower-like copper oxide microelectrodes for the sensitive detection of glucose and lactic acid in human serum and urine

Herein, we report self-supported gold dispersed copper oxide microflowers (Au@CuO MFs) on copper microelectrodes (CME) as a sensitive platform for the sensing of glucose and lactic acid in human serum...

Green Synthesis of Metal and Metal Oxide Nanoparticles Using Different Plants’ Parts for Antimicrobial Activity and Anticancer Activity: A Review Article

Nanotechnology emerged as a scientific innovation in the 21st century. Metallic nanoparticles (metal or metal oxide nanoparticles) have attained remarkable popularity due to their interesting biological, physical, chemical, magnetic, and optical properties. Metal-based nanoparticles can be prepared by utilizing different biological, physical, and chemical methods. The biological method is preferred as it provides a green, simple, facile, ecofriendly, rapid, and cost-effective route for the green synthesis of nanoparticles. Plants have complex phytochemical constituents such as carbohydrates, amino acids, phenolics, flavonoids, terpenoids, and proteins, which can behave as reducing and stabilizing agents. However, the mechanism of green synthesis by using plants is still highly debatable. In this report, we summarized basic principles or mechanisms of green synthesis especially for metal or metal oxide (i.e., ZnO, Au, Ag, and TiO2, Fe, Fe2O3, Cu, CuO, Co) nanoparticles. Finally, we explored the medical applications of plant-based nanoparticles in terms of antibacterial, antifungal, and anticancer activity.