Green synthesis of Copper Oxide/Carbon nanocomposites using the leaf extract of Adhatoda vasica Nees, their characterization and antimicrobial activity

Chemical Profiling and Biological Activities on Nepalese Medicinal Plant Extracts and Isolation of Active Fraction of Nyctanthes arbor-tristis

The importance of medicinal plants for the treatment of different diseases is high from the aspects of the pharmaceutical industry and traditional healers. The present study involves nine different medicinal plants, namely, Neolamarckia cadamba, Nyctanthes arbor-tristis, Pogostemon benghalensis, Equisetum debile, Litsea monopetala, Spilanthes uliginosa, Desmostachya bipinnata, Mallotus philippensis, and Phoenix humilis, collected from Chitwan district of Nepal for biochemical analysis followed by the isolation of active plant fractions from the bioactive plant extract. The methanolic extracts of roots, barks, seeds, seed cover, and the other aerial parts of plants were used for the phytochemical analysis and biological activities. The DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging assay was adopted to evaluate the antioxidant activity. Antibacterial activity was evaluated using the agar well diffusion method. The antidiabetic activity was studied by the α-amylase enzyme inhibition assay. The highest antioxidant activity was observed in extracts of Nyctanthes arbor-tristis followed by Mallotus philippensis (seed cover), Pogostemon benghalensis, Litsea monopetala, Phoenix humilis, and Neolamarckia cadamba with IC50 values of 27.38 ± 1.35, 32.08 ± 2.81, 32.75 ± 2.13, 33.82 ± 1.07, 40.14 ± 0.93, and 50.44 ± 3.75 µg/mL, respectively. The highest antidiabetic activity was observed in extracts of Phoenix humilis followed by Desmostachya bipinnata and Pogostemon benghalensis with IC50 values of 95.69 ± 6.97, 99.24 ± 12.6, and 106.3 ± 12.89 µg/mL, respectively. The mild α-amylase enzyme inhibition was found in extracts of Nyctanthes arbor-tristis, Spilanthes uliginosa Swartz, Litsea monopetala, and Equisetum debile showing IC50 values of 110.4 ± 7.78, 115.98 ± 10.24, 149.83 ± 8.3, and 196.45 ± 6.04 µg/mL, whereas Mallotus Philippensis (seed cover), Mallotus philippensis (seed), and Desmostachya bipinnata showed weak α-amylase inhibition with IC50 values of 208.87 ± 1.76, 215.41 ± 2.09, and 238.89 ± 9.27 µg/mL, respectively. The extract of Nyctanthes arbor-tristis showed high zones of inhibition against S. aureus (ATCC 25923) and E. coli (ATCC 25922) of ZOI 26 and 22 mm, respectively. The chemical constituents isolated from the active plant Nyctanthes arbor-tristis were subjected to GCMS analysis where the major chemical compounds were 11,14,17-eicosatrienoic acid and methyl ester. These results support the partial scientific validation for the traditional uses of these medicinal plants in the treatment of diabetes and infectious diseases by the people living in different communities of Chitwan, Nepal.

Blood proteins self-assembly, staphylococcal enterotoxins-interaction, antibacterial synergistic activities of biogenic carbon/FeSO4/Cu/CuO nanocomposites modified with three antibiotics

INTRODUCTION

Nanocomposites based on copper, iron, and carbon materials are novel nanomaterials with both antibacterial and biocompatibility properties considerable to fight against multidrug-resistant bacteria.

METHODS

In this study, phytogenic carbon/FeSO4/Cu/CuO nanocomposites modified by three antibiotics including tetracycline, amoxicillin, and penicillin were employed to hinder antibiotic resistant bacteria of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Interaction of albumin and hemoglobin as major blood proteins with these nanocomposites were evaluated by SEM, FTIR, and AFM techniques. As in silico study, molecular docking properties of staphylococcal enterotoxin toxin A and B with (Z)-α-Bisabolene epoxide, (E)-Nerolidol, α-Cyperone, daphnauranol C, nootkatin, and nootkatone as major secondary metabolites of Daphne mucronata were obtained by AutoDock Vina program.

RESULTS

Physicochemical characterization of nanocomposites showed (Zeta potential (- 5.09 mV), Z-average (460.2 d.nm), polydispersity index (0.293), and size range of 44.58 ± 6.78 nm). Results of both in vitro and in silico surveys disclosed significant antibacterial activity of antibiotic functionalized carbon/FeSO4/Cu/CuO nanocomposites compared to antibiotics alone towards Gram-negative and Gram-positive bacteria.

CONCLUSION

Synergistic activity of bio-fabricated carbon/FeSO4/Cu/CuO nanocomposites with antibiotics may be affected by main parameters of concentration and ratio of antibacterial agents, physicochemical properties of nanocomposites, bacterial type (Gram-negative or Gram-positive), antibacterial mechanisms, and chemical structure of antibiotics.

Phyto-assisted synthesis of CuO/industrial waste derived biochar composite for adsorptive removal of doxycycline hydrochloride and recycling of spent biochar as green energy storage device

The highest exposure of Endocrine disrupting compounds (EDC) into the water bodies as a result of extensive production and application of Covid-19 related drugs is a growing concern now a days. Herein, a novel nanocomposite material was developed by impregnating green synthesized copper oxide nanoparticles on the porous surface of fabric waste derived biochar to eliminate the concerned EDCs along with a sustainable disposal strategy for the spent adsorbent. Morphological characterizations by Field emission scanning electron microscopy confirmed the formation of hierarchical porous structured material. X-ray analysis revealed presence of both amorphous nature of biochar matrix as well as the crystalline nature attributed from monodispersion of copper oxide nanoparticles onto biochar surface. Batch sorption study showed removal of doxycycline hydrochloride (DOX) of >97% after 2 h at pH 7, 30 mg L-1 initial concentration of DOX and 2 g L-1 of adsorbent dose at room temperature after a two-step optimization process. Spectroscopic study and Raman shift suggested that pore filling, strong complexation and electrostatic interactions maximise the adsorption of DOX in the CuO/biochar composite as compared to the pristine biochar. However disposal of spent adsorbent is a crucial aspect for the environment and therefore, a sustainable recycling strategy for DOX loaded adsorbent as electrode material has been proposed for the first time in this study. Maximum specific capacitance value was observed in the range of 221.9-297.3 F g-1 for the DOX loaded nanocomposite at 1 mV s-1 comparable with other reported heteroatom-doped carbonaceous material as electrode. Therefore the excellent adsorption capacity of green synthesized CuO/biochar composite and its recycling after DOX adsorption can be recommended as a sustainable solution for mitigation of pharmaceuticals from wastewater. A detail study on degradation of DOX into eco-friendly products and its cost-effectiveness would be beneficial to suggest appropriate mitigation strategy for such compounds.

Green synthesis and characterization of silver and copper nanoparticles and their use as an effective adsorbent for chromium removal and recovery from wastewater

Chromium (Cr) is one of the hazardous heavy metals that is naturally carcinogenic and causes various health problems. Metallic nanoparticles such as silver and copper nanoparticles (Ag NPs and Cu NPs) have gained great attention because of their unique chemical, physical, and biological attributes, serving diverse and significant role in various useful and sustainable applications. In the present study, both of these NPs were synthesized by green method in which Azadirachta indica plant extract was used. These nanoparticles were characterized by using advanced instrumental techniques such as Fourier transmission infrared (FTIR), X-ray diffraction (XRD), scanning electron microscope attached with energy-dispersive spectroscopy (SEM-EDS), and elemental mapping. These environmentally friendly nanoparticles were utilized for the batch removal of Cr from the wastewater. For analysis of adsorption behaviour, a range of kinetic isotherm models (Freundlich, Temkin, Dubinin, and Langmuir) and kinetic models (pseudo-first-order and pseudo-second-order) were used for the Cu-NPs and Ag-NPs. Cu NPs exhibited the highest Cr removal efficiency (96%) within a contact time of 10-15 min, closely followed by Ag NPs which achieved a removal efficiency of 94% under the similar conditions. These optimal outcomes were observed at a sorbent dose of 0.5 g/L for Ag NPs and 0.7 g/L for Cu NPs. After effectively capturing Cr using these nanoparticles, the sorbates were examined through SEM-EDX analysis to observe how much Cr metal was attached to the nanoparticles, potentially for future use. The analysis found that Ag-NPs captured 18% of Cr, while Cu-NPs captured 12% from the aqueous solution. More precise experimental conditions are needed for higher Cr removal from wastewater and determination of the best conditions for industrial-level Cr reuse. Although nanomaterial exhibit high efficiency and selectivity for Cr removal and recovery from wastewater, more research is necessary to optimize their synthesis and performance for industrial-scale applications and develop efficient methods for Cr removal and recovery.

Green synthesis of silver nanoparticles using Adhatoda vasica leaf extract and its application in photocatalytic degradation of dyes

The paper describes biogenic synthesis of silver nanoparticles (AgNPs) using Adhatoda vasica leaf extracts at room temperature. The prepared AgNPs were characterized by UV-visible spectroscopy, Fourier-transform infrared spectroscopy, powder X-ray diffraction, Energy dispersive X-ray (EDX), High Resolution Transmission Electron Microscope, Scanning Electron Microscopy and Thermogravimetric analyser. The bio reduction method is devoid of any toxic chemicals, organic solvents, and external reducing, capping and stabilizing agent. The synthesized AgNPs had spherical shape with particle size ranging between 3.88 and 23.97 nm and had face centered cubic structure. UV-visible spectral analysis confirmed the formation of AgNPs with a characteristic surface plasmon resonance band at 419 nm. The EDX pattern revealed the presence of elemental Ag in AgNPs. The prepared AgNPs were used for degradation of Amaranth, Allura red and Fast green in aqueous medium, with ≥ 92.6% efficiency within 15 min using 5 mg of AgNPs. The optical bandgap, Eg value of 2.26 eV for AgNPs was found to be effective for rapid photocatalytic degradation of all the three dyes. The degradation process was observed to follow pseudo first order kinetics.

Exploring nanocomposites for controlling infectious microorganisms: charting the path forward in antimicrobial strategies

Nanocomposites, formed by combining a matrix (commonly polymer or ceramic) with nanofillers (nano-sized inclusions like nanoparticles or nanofibers), possess distinct attributes attributed to their composition. Their unique physicochemical properties and interaction capabilities with microbial cells position them as a promising avenue for infectious disease treatment. The escalating prevalence of multi-drug resistant bacteria intensifies the need for alternative solutions. Traditional approaches involve antimicrobial agents like antibiotics, antivirals, and antifungals, targeting specific microbial aspects. This review presents a comprehensive overview of diverse nanocomposite types and highlights the potential of tailored matrix and antibacterial agent selection within nanocomposites to enhance treatment efficacy and decrease antibiotic resistance risks. Challenges such as toxicity, safety, and scalability in clinical applications are also acknowledged. Ultimately, the convergence of nanotechnology and infectious disease research offers the prospect of enhanced therapeutic strategies, envisioning a future wherein advanced materials revolutionize the landscape of medical treatment.

Potential Uses of Adhatoda Vasica in Orthodontics

Plaque control, pain control, and modulation of inflammatory mediators to accelerate or stabilize tooth movements are hot issues in orthodontics. The recent advent of phytochemicals as biological mediators has opened new vistas in the aforementioned areas of orthodontics. Adhatoda vasica has caught the attention of investigators due to multiple properties related to orthodontics. This study addresses the potential areas of use of A. vasica in orthodontics, which provide ideas for further investigations. A. vasica possesses antibacterial activity, antifungal activity, anti-oxidant effect, anti-inflammatory activity, analgesic effect, osteogenic, and osteoclastic activities. A. vasica has huge potential in orthodontics, whereas all these vistas need careful and methodical testing before use in clinical orthodontics. In the future, investigators can focus on these aspects of the use of A. vasica to develop products.

Photocatalytic degradation of imidacloprid using Ag2O/CuO composites

Imidacloprid is one of the most commonly used neonicotinoid pesticides that has been identified as a neurotoxin for various non-target organisms. It binds to the central nervous system of organisms, causing paralysis and eventually death. Thus, it is imperative to treat waterwaters contaminated with imidacloprid using an efficient and cost effective method. The present study presents Ag₂O/CuO composites as excellent catalysts for the photocatalytic degradation of imidacloprid. The Ag₂O/CuO composites were prepared in different compositions by adopting the co-precipitation method and used as a catalyst for the degradation of imidacloprid. The degradation process was monitored using UV-vis spectroscopy. The composition, structure, and morphologies of the composites were determined by FT-IR, XRD, TGA, and SEM analyses. The effect of different parameters i.e time, concentration of pesticide, concentration of catalyst, pH, and temperature on the degradation was studied under UV irradiation and dark conditions. The results of the study evidenced the 92.3% degradation of imidacloprid in only 180 minutes, which was 19.25 hours under natural conditions. The degradation followed first-order kinetics, with the half life of the pesticide being 3.7 hours. Thus, the Ag₂O/CuO composite was an excellent cost-effective catalyst. The non-toxic nature of the material adds further benefits to its use. The stability of the catalyst and its reusability for consecutive cycles make it more cost effective. The use of this material may help to ensure an immidacloprid free environment with minimal use of resources. Moreover, the potential of this material to degrade other environmental pollutants may also be explored.

Green Synthesis of Fluorescent Carbon Dots from Annona squamosa Leaves: Optical and Structural Properties with Bactericidal, Anti-inflammatory, Anti-angiogenesis Applications

A hydrothermal method was employed for green synthesis of fluorescent carbon dots (GCDs) from Annona squamosa leaves. The synthesized GCDs were confirmed by microscopic and spectroscopic techniques such as: High Resolution Transmission Electron Microscopy (HR-TEM), Atomic Force Microscopy (AFM), UV-Vis spectrometry, Fluorescence spectrometry, X-Photoelectron Spectroscopy (XPS), X-ray Diffraction spectroscopy (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). The produced GCDs had shown multiple properties, including massive antibacterial activity at concentration 200 μg/ml. The stabilization of human red blood cells served as a method to assess the anti-inflammatory activity. We also looked at how GCDs affected the angiogenesis process. The density of blood vessels was significantly decreased after treatment with GCDs, according to the results of the Chorio-Allantoic Membrane assay (p < 0.05). As per the study prepared GCDs from fallen leaves of Annona squamosa have multifunctional applications.

Green synthesis of spermine coated iron nanoparticles and its effect on biochemical properties of Rosmarinus officinalis

In this study, aqueous spinach extract was used for the green synthesis of iron nanoparticles. The surface of iron oxide nanoparticles was coated with spermine. The physicochemical properties of nanoparticles were investigated using UV-Vis, TGA, FTIR, VSM, TEM, and DLS. The results showed that the nanoparticles had a spherical structure. The surface charge of the Fe₃O₄-NPs increased from -3.2 to 18.42 (mV) after Fe₃O₄ coating by spermine. In order to investigate the effect of nanoparticles on physicochemical properties of rosemary under drought stress conditions, an experiment was carried out in a completely randomized design. The results showed that the amount of antioxidant enzymes and secondary metabolites increased significantly under drought stress. Moreover, the use of spermine-coated iron nanoparticles can be useful in increasing resistance to drought stress in plants by increasing the activity of some antioxidant enzymes and secondary metabolites. The biocompatibility of Nanoparticles in cell suspension was investigated. the ability of Fe₃O₄-SM NPs to interact with DNA and protect it against DNaseI and ultrasonic waves using agarose gel electrophoresis was studied. The ability of Fe₃O₄-SM to neutralize the negative charge of DNA and protect it against DNaseΙ and ultrasonic waves was confirmed using an agarose gel electrophoresis assay.

Anti-inflammatory effect of simvastatin by impeding TNF-α and interleukin-1ß pathways: antiangiogenic activity of simvastatin and simvastatin-loaded silver nanoparticles

PURPOSE

The present study was carried out to evaluate anti-inflammatory and antiangiogenic attributes of simvastatin and its nanofilms containing silver nanoparticles.

METHODS

Silver nanoparticles and simvastatin-loaded nanocomposite (SNSN) films were formulated by using polymeric solution (pectin + sericin) through casting solution method. Different in vitro and in vivo anti-inflammatory assays were performed. In addition, chick chorioallantoic membrane assay (CAM) was also employed for angiogenesis activity.

RESULTS

FTIR spectra of the film depicted the presence of intact simvastatin. Differential scanning calorimetry exhibited no endothermic expression in F9 film thermogram. The simvastatin release from all films exhibited a burst effect. Cotton-pellet induced granuloma model study showed that high dose of simvastatin and indomethacin produced comparable (p < 0.05) anti-inflammatory effect. Noteworthy, RT-PCR showed dose-dependent, anti-oedematous effect of simvastatin through downregulation of serum TNF-α and interleukin-1ß levels. While results of CAM assay exhibited remarkable anti-angiogenic potential of SNSN films showing dissolved blood vessels network macroscopically.

CONCLUSION

To reiterate, simvastatin and its SNSN films can add significant contribution to the field of biomedicines due to their promising anti-inflammatory and antiangiogenic properties, however, clinical studies are required to validate their commercial use.

Recent progress in bio-mediated synthesis and applications of engineered nanomaterials for sustainable agriculture

The ever-increasing demand for agricultural food products, medicine, and other commercial sectors requires new technologies for agricultural practices and promoting the optimum utilization of natural resources. The application of engineered nanomaterials (ENMs) enhance the biomass production and yield of food crop while resisting harmful environmental stresses. Bio-mediated synthesis of ENMs are time-efficient, low-cost, environmentally friendly, green technology. The precedence of using a bio-mediated route over conventional precursors for ENM synthesis is non-toxic and readily available. It possesses many active agents that can facilitate the reduction and stabilization processes during nanoparticle formation. This review presents recent developments in bio-mediated ENMs and green synthesis techniques using plants, algae, fungi, and bacteria, including significant contributions to identifying major ENM applications in agriculture with potential impacts on sustainability, such as the role of different ENMs in agriculture and their impact on different plant species. The review also covers the advantages and disadvantages of different ENMs and potential future research in this field.

Anti-Inflammatory and Anti-Angiogenic Aattributes of Moringa olifera Lam. and its Nanoclay-Based Pectin-Sericin films

Background: Inflammation is a strong reaction of the non-specific natural immune system that helps to start protective responses against encroaching pathogens and develop typical immunity against intruding factors. However, prolonged inflammation may lead to chronic autoimmune diseases. For thousands of years, medicinal plants have served as an excellent source of treatment for chronic pathologies such as metabolic diseases.

Purpose: The present study aims to evaluate the anti-inflammatory and anti-angiogenic potential of Moringa olifera Lam. extract (MO) and Moringa-loaded nanoclay films.

Methods: The extract preparation was done through the maceration technique using absolute methanol (99.7%) and labelled as Mo. Me. Mo. Me-loaded nanoclay-based films were prepared by using pectin and sericin (Table 1). The in vitro studies characterized the film thickness, moisture, and phytochemical contents. The in vivo anti-inflammatory tests involved using a cotton pellet-induced granuloma model assay. In addition, the chick chorioallantoic membrane (CAM) assay was employed for angiogenesis activity.

Results: The phytochemical analysis of the extract confirmed the presence of alkaloids, glycosides, flavonoids and phytosterol. This extract contained quercetin in a large quantity. Cotton-pellet induced granuloma model study revealed a comparable (p > 0.05) effect of a high dose of Mo. Me (500 mg/kg) as compared with standard drug. Noteworthy, data obtained through the RT-PCR technique manifested the dose-dependent anti-oedematous effect of Moringa olifera via downregulation of TNF-α and interleukin-1ß. The findings of the CAM assay exhibited a remarkable anti-angiogenic activity of Mo. Me loaded nanoclay films, showing diffused vasculature network in the macroscopic snapshot.

Conclusion:Moringa olifera and its nanocomposite films have therapeutic potential against inflammation.

Green synthesis of copper oxide nanoparticles using Abutilon indicum leaves extract and their evaluation of antibacterial, anticancer in human A549 lung and MDA-MB-231 breast cancer cells

In currently, biosynthesis of copper oxide nanoparticles (CuO NPs) are most widely used numerous in biological applications such as biosensor, energy, medicine, agriculture, environmental and industrial wastewater treatment. The hierarchical CuO NPs was synthesized via green chemistry method by using of Abutilon indicum (A. indicum) leaf extract, its nontoxic, facile and low-cost approaches. Biogenic synthesized CuO NPs was characterized by using a UV-visible absorption spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Field mission scanning electron microscopy (FE-SEM) with Energy-dispersive X-ray spectroscopy (EDX) analysis. The synthesized CuO NPs was performed antibacterial activity against human pathogenic organisms of both Gram negative (Escherichia coli and Salmonella typhi) and Gram positive (Bacillus subtilis and Staphylococcus aureus) bacteria by using agar well diffusion method. Biological synthesized CuO NPs was showed potential bactericidal activity against Gram positive bacteria of B. subtilis than compared to Gram negative bacteria of E. coli. The cytotoxic effect of A. indicum mediated synthesized CuO NPs was evaluated against to human lung A549 and breast MDA-MB-231cancer cell lines by determined using of MTT assay. In furthermore, photocatalytic dye degradation was performed that synthesized CuO NPs have effectively removed 78% of malachite green dye molecule. Our investigation results suggested that the green synthesized CuO NPs potential biological activity of antibacterial activity against Gram positive bacterial, anticancer activity was effectively against MDA-MB-231cancer cell line and good dye degradation was exhibited in malachite green. The A. indicum aqueous leaf extract mediated synthesized CuO NPs has strongly suggested promising nano-biomaterials for fabrication of biomedical applications.

DAT and PRX1 gene expression modulates vincristine production in Catharanthus roseus L. propagates using Cu, Fe and Zn nano structures

Underlying mechanism of nanostructures upon monoterpene induction in Catharanthus roseus has not been explored yet. In the current study, Copper, Iron and Zinc nanoparticles were biosynthesized by Eriobotrya japonica seed extract and capped with reduced glutathione. Biosynthesized nanoparticles and their capped analogues were characterized by UV-visible spectrophotometer, FTIR, XRD and SEM. Selected concentration of nanostructures were used in plant tissue culture media which instigated the production of alkaloids, tannins and flavonoids without significantly affecting the growth index of propagated calli and shoots cultures of C. roseus. Accelerated vincristine production was noticed in propagated calli and shoots under copper and zinc nanostress (1645-1865 μg/ml respectively) with the least effect by iron nanostructure. Highest concentration of calcium was recorded in in vitro shoots under capped (3.42 mg/ml ± 7.16) and uncapped (4.41 mg/ml ± 20.44) Zn nanoparticles compared to control (2.82 mg/ml ± 13.41). Real time PCR depicts nano-zinc mediated increased expression of DAT and PRX1 genes of TIA pathway. Significant correlation among PRX1/DAT gene expression with vincristine production and calcium accumulation in the presence of nanostress validate by PCA. This study paved way the opportunities of metal biogenic nanomaterials as an ideal drug modulator in plant tissue culture studies.

Ecofriendly Synthesis of Biosynthesized Copper Nanoparticles with Starch-Based Nanocomposite: Antimicrobial, Antioxidant, and Anticancer Activities

In recent years, polysaccharides-based nanocomposites have been used for biomedical applications. In the current study, a nanocomposite based on myco-synthesized copper nanoparticles (CuNPs) and starch was prepared. The prepared nanocomposite was fully characterized using UV-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), mapping, transmission electron microscope (TEM), and dynamic light scattering (DLS). Results revealed that this nanocomposite is characterized by nano spherical shape ranged around 200 nm as well as doped with CuNPs with size about 9 nm. Antimicrobial, antioxidant, and anticancer activities of the prepared nanocomposite were evaluated. Results revealed that CuNPs-based nanocomposite exhibited outstanding antibacterial and antifungal activity toward Escherichia coli ATCC25922, Bacillus subtilis ATCC605, Candida albicans ATCC90028, Cryptococcus neoformance ATCC 14,116, Aspergillus niger RCMB 02,724, A. terreus RCMB 02,574, and A. fumigatus RCMB 02,568. Moreover, CuNPs-based nanocomposite has a strong antioxidant activity as compared to ascorbic acid, where IC₅₀ was 18 µg/mL. Cytotoxicity test of CuNPs-based nanocomposite revealed that this nanocomposite is safe in use, where IC₅₀ was 185.1 µg/mL. Furthermore, CuNPs-based nanocomposite exhibited potential anticancer activity against MCF7 cancerous cell line where IC₅₀ was 62.8 µg/mL which was better than CuNPs alone. In conclusion, the prepared CuNPs with starch-based nanocomposite is promising for different biomedical applications as antimicrobial, antioxidant, and anticancer activities.

Synthesis, Characterization, and In Vivo Toxicological Evaluation of Copper (II) Oxide Containing Herbometallic Siddha Nanocomplex “Thamira Parpam”

“Thamira parpam” (TP), a copper-based herbometallic oxide (copper (II) oxide) nanodrug has been used in Siddha medicine for centuries because of its anti-ulcerogenic property. However, the physicochemical properties and in vivo toxicity of TP still remain elusive. Rigorous clinical translation requires deciphering these vital properties. We have synthesized TP following a gold standard protocol in the traditional Siddha methodology. We assessed the size, phase, elemental constituents, and thermal stability of TP by SEM and TEM, XRD, EPR, and EDAX analyses, respectively. The results depicted the conversion of metallic copper into copper (II) oxide in the final stages of TP preparation and exhibited nanodimensions ranging between 10 and 50 nm. The XPS spectra revealed the presence of oxygen-deficient state and a carbonaceous coating was found on the surface of TP using TEM analysis. In vivo safety was studied in rat toxicity models by adopting OECD guidelines. Body weight changes, feed, and water intake were unaltered upon TP administration. Hematological, biochemical profiling, and histopathological findings also suggested its nontoxic nature with no abnormalities in major organs and its functions. Interestingly, we found that the metal toxicity could have been subdued because of the carbonaceous coating around the nanoparticle copper (II) oxide, confirming that the drug is safe at a low dose. Overall, our study has enlightened the safety of TP supporting the use of Siddha formulations.

Copper Oxide Nanoparticle-Decorated Carbon Nanoparticle Composite Colloidal Preparation through Laser Ablation for Antimicrobial and Antiproliferative Actions against Breast Cancer Cell Line, MCF-7

Copper oxide (CuO) nanoparticle- (NP-) decorated carbon NPs (CNPs) were produced as colloidal suspension through pulsed laser ablation technique in liquid (PLAL) medium. The antimicrobial activity of the produced NPs was tested against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), and anticancer activity was tested against breast cancer cell line, MCF-7, together with the biocompatibility assessment of these NPs. The X-ray diffraction (XRD) patterns of the obtained CNPs showed peaks at 26.58° and 43.78° (2θ) identical to (002) and (111) planes, respectively, of the carbon phases. It also displayed new peaks at 38.5° and 48.64° (2θ) after doping with CuO NPs. Transmission electron microscope (TEM) images revealed the crystalline nature with the spherical shape of the prepared CNPs with 5-40 nm diameter ranges. In addition, the NP effects on the bacterial cell walls and nucleic acid were confirmed using a scanning electron microscope (SEM) and microscopic fluorescence analysis. The NPs showed antibacterial activity through SEM examinations against the pathogenic microbial species, S. aureus and E. coli. In the cellular material release assay, the optical density of the bacterial cells, treated with NPs, displayed a significant increase with the time of exposure to NPs, and the cytotoxicity reached more than 80% of the level for the CNPs decorated with CuO NPs. The morphology of the MCF-7 cells treated with NPs decreased numbers, and the loss of contact with the surrounding cells was observed. These results confirmed that the CNPs decorated with CuO NPs have no observable side effects and can be safely used for therapeutic applications. It is also noteworthy that it is the first report of preparation of CuO NPs decorated with CNPs (CuO NPs-CNPs) by PLAL, and the produced NPs showed antimicrobial antiproliferative activities against breast cancer cell lines, MCF-7. The main advantage of the PLAL technique of synthesizing CuO NPs-CNPs provided a two-step, cost-effective, and eco-friendly method.

Green approaches for the synthesis of metal and metal oxide nanoparticles using microbial and plant extracts

Green synthesis approaches are gaining significance as promising routes for the sustainable preparation of nanoparticles, offering reduced toxicity towards living organisms and the environment. Nanomaterials produced by green synthesis approaches can offer additional benefits, including reduced energy inputs and lower production costs than traditional synthesis, which bodes well for commercial-scale production. The biomolecules and phytochemicals extracted from microbes and plants, respectively, are active compounds that function as reducing and stabilizing agents for the green synthesis of nanoparticles. Microorganisms, such as bacteria, yeasts, fungi, and algae, have been used in nanomaterials' biological synthesis for some time. Furthermore, the use of plants or plant extracts for metal and metal-based hybrid nanoparticle synthesis represents a novel green synthesis approach that has attracted significant research interest. This review discusses various biosynthesis approaches via microbes and plants for the green preparation of metal and metal oxide nanoparticles and provides insights into the molecular aspects of the synthesis mechanisms and biomedical applications. The use of agriculture waste as a potential bioresource for nanoparticle synthesis and biomedical applications of biosynthesized nanoparticles is also discussed.

One-pot synthesis of a highly disperse core–shell CuO–alginate nanocomposite and the investigation of its antibacterial and catalytic properties

Sodium alginate extracted from native algae of the Persian Gulf for use in the synthesis of a highly disperse CuO–alginate nanocomposite, which is used as an antibacterial agent as well as a catalyst in the synthesis of amides.

Green approaches for the synthesis of metal and metal oxide nanoparticles using microbial and plant extracts

Green synthesis approaches are gaining significance as promising routes for the sustainable preparation of nanoparticles, offering reduced toxicity towards living organisms and the environment.

Wet chemical development of CuO/GO nanocomposites: its augmented antimicrobial, antioxidant, and anticancerous activity

This study employed a bottom-up technique to synthesize copper oxide (CuO) nanoparticles over hydrophilic graphene oxide (GO) nanosheets. The CuO/GO nanocomposite has been prepared using two selected precursors of copper nitrate and citric acid with an intermittent mixing of GO solutions. The synthesized Nanocomposites were characterized using different biophysical techniques like FT-IR, NMR, FE-SEM, and HR-TEM analyses. FT-IR analyses confirm the nanocomposites' successful formation, which is evident from the functional groups of C=C, C-O, and Cu-C stretching vibrations. Morphological analyses reveal the depositions of CuO nanoparticles over the planar rough GO sheets, which has been elucidated from the FE-SEM and HR-TEM analyses supported by respective EDAX analyses. The antimicrobial activities have been evident from the surface roughness and damages seen from the FE-SEM analyses. The CuO/GO sheets were tested against Gram-positive (e.g., Staphylococcus aureus) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa). It is evident that the intrinsic antibacterial activity of CuO/GO sheets, when combined in equal proportions, elicited a robust antibacterial activity when tested over Gram -ve representative bacteria Escherichia coli. The antioxidant behaviour of synthesized CuO/GO nanocomposite was evaluated by scavenging the free radicals of DPPH and ABTS. Moreover, the cytotoxic activity was also studied against epidermoid carcinoma cell line A-431. A brief mathematical formulation has been proposed in this study to uncover the possibilities of using the nanocomposites as potential drug candidates in theranostic applications in disease treatment and diagnosis. This study would help uncover the electronic properties that play in the nano-scaled system at the material-bio interface, which would aid in designing a sensitive nano-electromechanical device bearing both the therapeutic and diagnostic attributes heralding a new horizon in the health care systems.

N,Cl-Codoped Carbon Dots from Impatiens balsamina L. Stems and a Deep Eutectic Solvent and Their Applications for Gram-Positive Bacteria Identification, Antibacterial Activity, Cell Imaging, and ClO- Sensing

In this study, we first synthesized metal-free N,Cl-doped carbon dots (N,Cl-CDs) using Impatiens balsamina L. stems as green precursors in a deep eutectic solvent (DES). The obtained N,Cl-CDs were characterized through transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, fluorescence (FL) spectroscopy, and ultraviolet (UV) spectroscopy. In addition to the common features of carbon dots (CDs), such as high light stability, small size, low toxicity, good aqueous solubility, and favorable biocompatibility, these N,Cl-CDs exhibited excellent recognition and selectivity for Gram-positive bacteria by doping with N and Cl elements using DES. The N,Cl-CDs with positive charge cannot only differentiate Gram-positive bacteria by selective fluorescence imaging but also have antibacterial effects on Gram-positive bacteria. Through potential, ROS, and morphological analyses of bacteria before and after treatment with N,Cl-CDs, the antibacterial mechanisms of bacteriostasis, Enterococcus faecium, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Salmonella were explored. In addition, N,Cl-CDs demonstrated low cytotoxicity and good cell imaging ability in cancer and normal cells. Moreover, they can be used as a fluorescence sensor for the detection of ClO^- with a detection range from 100 nM to 40 μM and a limit of detection (LOD) of 30 nM. In summary, the prepared N,Cl-CDs could be applied as environmentally friendly Gram-positive bacterial identification and antibacterial agents. Additionally, their cell imaging and ClO^- detection abilities were outstanding.

Prospective Application of Nanoparticles Green Synthesized Using Medicinal Plant Extracts as Novel Nanomedicines

The use of medicinal plants in green synthesis of metal nanoparticles is increasing day by day. A simple search for the keywords "green synthesis" and "nanoparticles" yields more than 33,000 articles in Scopus. As of August 10, 2021, more than 4000 articles have been published in 2021 alone. Besides demonstrating the ease and environmental-friendly route of synthesizing nanomaterials, many studies report the superior pharmacological properties of green synthesized nanoparticles compared to those synthesized by other methods. This is probably due to the fact that bioactive molecules are entrapped on the surface of these nanoparticles. On the other hand, recent studies have confirmed the nano-dimension and biocompatibility of metal ash (Bhasma) preparations, which are commonly macerated with biological products and administered for the treatment of various diseases in Indian medicine since ancient times. This perspective article argues for the prospective medical application of green nanoparticles in the light of Bhasma.

Bacteriostatic impact of nanoscale zero-valent iron against pathogenic bacteria in the municipal wastewater

Nanoscale zero-valent iron particles were investigated as an antibacterial agent against two Gram-positive bacteria; Staphylococcus aureus NRRL B-313 (S. aureus), Bacillus subtilus NRC (B. subtilus), and two Gram-negative bacteria; Escherichia coli NRC B-3703 (E. coli), Pseudomonas aeruginosa NRC B-32 (Ps. aeruginosa). The characterization of synthesized nZVI particles was obtained by XRD, SEM, EDX, and TG analyses. The results demonstrated that the nZVI particles have a spherical shape, mean crystalline size of 44.43 nm, and exhibited a good chemical and thermal stability performance under different physical conditions. The bacterial suspensions were subjected to the treatment using nZVI particle suspensions with a concentration of 10 mg/mL. The minimum inhibitory concentration of nZVI particles was determined using the well diffusion assay method and found to be 15, 10, 10, and 5 mg for the following four strains; S. aureus, B. subtilus, E. coli, and Ps. aeruginosa, respectively. The biological treatment results of municipal wastewater using nZVI particles revealed that the counts of total bacteria, total coliform, fecal coliform, S. aureus, fecal Streptococcus, and E. coli were decreased to 44.29%, 51.76%, 90.95%, 46.67%, 33.33%, and 93.89%, respectively, while the Ps. aeruginosa not detected in the wastewater sample. The enhanced inactivation performance of nZVI nanoparticles was mainly attributed to the reactive oxygen species (ROS) production, releasing of iron corrosion products like Fe²⁺/Fe³⁺ ions, and direct friction of nZVI particles with bacterial cells membranes. In addition, the nZVI particles presented a striking disinfection behavior in comparison with other widespread disinfection technologies such as chlorination. Accordingly, the obtained results introduce the nZVI particles as a promising disinfection technology.

Evaluation of Antimicrobial and Antibiofilm Activities of Copper Oxide Nanoparticles within Soft Denture Liners against Oral Pathogens

OBJECTIVES

Soft denture liners provide a favorable environment for adhesion and colonization of microorganisms. This in vitro study aimed to examine the efficacy of different concentrations of copper oxide nanoparticles (CuO NPs) incorporation into soft denture liner on the biofilm formation of the microbial species.

METHODS

Field Emission Scanning Electron Microscopy (FESEM) images from NPs were recorded. Antifungal susceptibility testing of CuO NPs against five standard strains of Candida albicans (CBS 10261, 1905, 1912, 1949, 2730), Streptococcus mutans (ATCC35668), Streptococcus sobrinus (ATCC27607), and Streptococcus salivarius (ATCC9222) was performed by the broth microdilution method with the Clinical and Laboratory Standards Institute reference method. The biofilm inhibition percentages of CuO NPs on the soft denture liners were determined by XTT assay.

RESULTS

The characterization of CuO NPs by scanning electron microscope (SEM) analyses confirmed the synthesis of NPs with appropriate structure and size with a mean diameter of 18.3 ± 9.1 nm. The CuO NPs successfully inhibited the growth of the tested standard strains of C. albicans and Streptococcus spp. at concentrations ranging from 64 to 128 µg mL-1. Indeed, incorporation of CuO NPs at a concentration of 500 µg mL-1 into the soft denture liners exhibited a significant activity (75%) in inhibition of C. albicans. biofilm formation in a dose-dependent manner. The biofilm formation of C. albicans in the presence of CuO NPs was lower than Streptococcus spp. in comparison with the control group (p < 0.05).

CONCLUSION

Incorporation of CuO NPs significantly decreased the colonization and plaque formation of the oral pathogens, especially C. albicans accumulation. These NPs may be useful as a promising agent for the antimicrobial management of soft denture liner materials.

R, P. R, Kalia A, Bhardwaj K, Bhardwaj P, Abd-Elsalam KA, Valis M, Kuca K. Nanohybrid Antifungals for Control of Plant Diseases: Current Status and Future Perspectives

The changing climatic conditions have led to the concurrent emergence of virulent microbial pathogens that attack crop plants and exhibit yield and quality deterring impacts on the affected crop. To counteract, the widespread infections of fungal pathogens and post-harvest diseases it is highly warranted to develop sustainable techniques and tools bypassing traditional agriculture practices. Nanotechnology offers a solution to the problems in disease management in a simple lucid way. These technologies are revolutionizing the scientific/industrial sectors. Likewise, in agriculture, the nano-based tools are of great promise particularly for the development of potent formulations ensuring proper delivery of agrochemicals, nutrients, pesticides/insecticides, and even growth regulators for enhanced use efficiency. The development of novel nanocomposites for improved management of fungal diseases can mitigate the emergence of resilient and persistent fungal pathogens and the loss of crop produce due to diseases they cause. Therefore, in this review, we collectively manifest the role of nanocomposites for the management of fungal diseases.

Compositions and antimicrobial properties of binary ZnO-CuO nanocomposites encapsulated calcium and carbon from Calotropis gigantea targeted for skin pathogens

Calotropis gigantea (C. gigantea) extract with an ecofriendly nanotechnology approach could provide promising antimicrobial activity against skin pathogens. This study investigates the antimicrobial capability of green synthesized binary ZnO-CuO nanocomposites from C. gigantea against non-MDR (Staphylococcus aureus and Escherichia coli) and MDR (Klebsiella pneumoniae, Pseudomonas aeruginosa and methicillin-resistant S. aureus) skin pathogens. Scanning electron microscopy and transmission electron microscopy revealed the size and shape of B3Z1C sample. Results of X-ray powder diffraction, energy-dispersive spectroscopy, FTIR and UV-Vis spectroscopy analyses confirmed the presence of mixed nanoparticles (i.e., zinc oxide, copper oxide, carbon and calcium) and the stabilising phytochemical agents of plant (i.e., phenol and carbonyl). Antimicrobial results showed that carbon and calcium decorated binary ZnO-CuO nanocomposites with compositions of 75 wt% of ZnO and 25 wt% CuO (B3Z1C) was a strong bactericidal agent with the MBC/MIC ratio of ≤ 4 and ≤ 2 for non-MDR and MDR pathogens, respectively. A significant non-MDR zone of inhibitions were observed for BZC by Kirby-Bauer disc-diffusion test. Further time-kill observation revealed significant fourfold reduction in non-MDR pathogen viable count after 12 h study period. Further molecular studies are needed to explain the biocidal mechanism underlying B3Z1C potential.