Synthesis, characterization, and photocatalytic activities of green sol-gel ZnO nanoparticles using Abelmoschus esculentus and Salvia officinalis: A comparative study versus co-precipitation-synthesized nanoparticles

Antihyperglycemic activity of polyphenolic metabolites and biosynthesized silver nanoparticles from Pedalium murex: Characterization and application of antioxidant and uropathogenic antimicrobial activities

Pedalium murex commonly known as (large caltrops, bara gokhru) is a medicinal plant with potential therapeutic benefits. Hyperglycemia, a hallmark of diabetes, affects millions worldwide. Research on its leaf ethanol extract demonstrates potential for managing hyperglycemia in vitro and in vivo. Phytochemical analysis revealed secondary metabolites, including tannins, alkaloids, saponins, flavonoids, and polyphenols, with high levels of total flavonoids (287.5 ± 17.3 μg QEq./mg) and polyphenols (327.5 ± 17.2 μg QEq./mg). Scanning electron microscopy (SEM) confirmed the granular nature of synthesized silver nanoparticles (AgNPs) with a size range of 20-40 nm, while transmission electron microscopy (TEM) showed spherical AgNPs (20-50 nm). Energy-dispersive X-ray spectroscopy (EDX) identified silver (66.75 %), carbon (22.02 %), and oxygen (11.23 %) as the primary components. The extract effectively neutralized DPPH-free radicals (39.57 ± 4.77 %), while the AgNPs showed greater efficacy (68.23 ± 5.37 %). Superoxide radical (O2•-) reduction was significant for both the extract (59.33 ± 0.17 %) and AgNPs (38.73 ± 0.21 %), highlighting potent antioxidant properties. Hydroxyl radical (●OH) scavenging was higher for the extract (63.72 ± 0.17 %) than for AgNPs alone (36.71 ± 0.29 %). The AgNPs showed significant antimicrobial activity, with inhibition zones of 16.27 ± 0.18 mm against Staphylococcus aureus and 11.23 ± 0.17 mm against Candida albicans at 80 μg/mL. In toxicity studies, P. murex-AgNPs were well tolerated in mice. In hyperlipidemic mice, treatment with P. murex-AgNPs (350 mg/kg and 700 mg/kg) significantly reduced cholesterol, triglycerides, and LDL-c levels without affecting HDL-c. These findings provide valuable insights into the therapeutic potential of P. murex-AgNPs for the treatment of hyperlipidemia and diabetes.

Ovalbumin-Mediated Biogenic Synthesis of ZnO and MgO Nanostructures: A Path Toward Green Nanotechnology

Sustainable and eco-friendly synthesis methods for nanoparticles are crucial for advancing green nanotechnology. This study presents the biogenic synthesis of zinc oxide (ZnO) and magnesium oxide (MgO) nanoparticles using ovalbumin, an abundant and non-toxic protein from egg white. The synthesis process was optimized by varying metal ion concentrations to control particle size and morphology. Characterization using ATR-FTIR, XRD, SEM, and UV-VIS confirmed the successful formation of uniform, well-crystallized nanoparticles with sizes ranging from 7.9 to 13.5 nm. ZnO nanoparticles exhibited superior antimicrobial efficacy against Escherichia coli and Enterococcus faecalis, while MgO nanoparticles showed enhanced potential environmental remediation. These findings highlight ovalbumin as a versatile agent for the green synthesis of ZnO and MgO nanomaterials, with promising applications in the medical, environmental, and optoelectronic fields. The results indicate that this biogenic method can serve as a sustainable proposal to produce nanostructured materials with diverse applications in the medical and environmental fields, such as eliminating pathogenic bacteria and purifying contaminated environments. Overall, this study significantly contributes to the development of sustainable nanomaterials and opens up new perspectives on the use of ovalbumin protein in the synthesis of multifunctional nanostructured materials.

Photo and electrochemical applications of green synthesized ZnO/Ag2O nanocomposites materials under visible light using P. macrosolen L. leaf

This study investigates the photo-catalytic and super-capacitive properties of green-synthesized ZnO/Ag2O nanocomposites using P. macrosolen L. leaf extract. The synthesis was performed in a single step at low temperature with a short reaction time. The synthesized materials were characterized using XRD, SEM, TEM, FTIR, UV-VIS and XPS. The ZnO/Ag2O nanocomposites exhibited exceptional photo-catalytic efficiency and stability under visible light for the degradation of carbon-based dyes. The degradation rate constants of the optimized ZnO/Ag2O nanocomposites were 0.054351 min⁻¹ for Methylene Orange (MO) and 0.048751 min⁻¹ for Toluidine Blue (TB), achieving degradation efficiencies of 99.69% and 98.50%, respectively, compared to ZnO (0.0075 min⁻¹). This remarkable improvement in visible-light photo-catalytic performance is attributed to the hetero-junction formation, which enhances charge separation and transfer through the matched crystal lattices and energy bands of Ag2O and ZnO. The Ag2O nanoparticles efficiently generate and transfer excited electrons to the ZnO conduction band under visible-light irradiation. Electrochemical studies revealed a significant improvement in specific capacitance, with the ZnO/Ag2O composite containing 50 wt% AgNO3 achieving a maximum specific capacitance of 655.0 F/g at a scan rate of 10 mV/s. This superior performance highlights the synergistic effect of ZnO and Ag2O in improving photo-catalytic and electrochemical properties. These findings demonstrate the potential of ZnO/Ag2O nanocomposites for industrial dye degradation and super-capacitor applications.

Eco-benevolent synthesis of ZnO-NPs and ZnO-MFs from Inula oculus-christi L. (Asteraceae) with effective antioxidant, antimicrobial, DNA cleavage, and decolorization efficiencies

As a result of the changes occurring globally in recent years, millions of people are facing challenging and even life-threatening diseases such as cancer and the COVID-19 pandemic, among others. This phenomenon has spurred researchers towards developing and implementing innovative and environmentally friendly scientific methods, merging disciplines with significant technological potential, such as nanotechnology with medicinal plants. Therefore, the focus of this research is to synthesize zinc nanoparticles (ZnO-NPs) and microflowers (ZnO-MFs) using extracts of the medicinal plant I. oculus christi prepared in n-hexane and methanol as new bioreduction and capping agents through a simple and environmentally friendly chemical approach. Optical, thermal, and morphological structural analyses of ZnO-NPs and ZnO-MFs were conducted using Ultraviolet-Visible (UV-Vis) spectroscopy, Fourier Transform Infrared (FT-IR) spectroscopy, Thermogravimetric Analysis (TGA), and Field Emission Scanning Electron Microscopy (FE-SEM). Metabolic profiles of extracts from different plant parts were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) and supported by visualization of contents through Principal Component Analysis (PCA), hierarchical cluster analysis heatmaps, and Pearson correlation graphs. Interestingly, ZnO-NPs and ZnO-MFs exhibited strong antioxidant properties and demonstrated particularly potent antimicrobial activity against Micrococcus luteus NRRL B-4375, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231 strains compared to standard antibiotics. Furthermore, ZnO-NPs and ZnO-MFs showed excellent plasmid DNA-cleavage activity of pBR322 with increasing doses. The photocatalytic performance of the synthesized ZnO-NPs and ZnO-MFs was evaluated for methylene blue (MB), congo red (CR), and safranin-O (SO) dyes, demonstrating remarkable color removal efficiency. Overall, the results provide a promising avenue for the green synthesis of ZnO-NPs and ZnO-MFs using I. oculus-christi L. inflorescence and pappus extracts, potentially revolutionizing biopharmaceutical and catalytic applications in these fields.

Advancements in nanoparticle-modified zeolites for sustainable water treatment: An interdisciplinary review

The contamination of water sources with heavy metals, dyes, and other pollutants poses significant challenges to environmental sustainability and public health. Traditional water treatment methods often exhibit limitations in effectively addressing these complex contaminants. In response, recent developments in nanotechnology have catalyzed the exploration of novel materials for water remediation, with nanoparticle-doped zeolites emerging as a promising solution. This comprehensive review synthesizes current literature on the integration of nanoparticles into zeolite frameworks for enhanced contaminant removal in water treatment applications. We delve into synthesis methodologies, elucidate mechanistic insights, and evaluate the efficacy of nanoparticle-doped zeolites in targeting specific pollutants, while also assessing considerations of material stability and environmental impact. The review underscores the superior adsorptive and catalytic properties of nanoparticle-doped zeolites, owing to their high surface area, tailored porosity, and enhanced ion-exchange capabilities. Furthermore, we highlight recent advancements in heavy metal and organic pollutant uptake facilitated by these materials. Additionally, we explore the catalytic degradation of contaminants through advanced oxidation processes, demonstrating the multifunctionality of nanoparticle-doped zeolites in water treatment. By providing a comprehensive analysis of existing research, this review aims to guide future developments in the field, promoting the sustainable utilization of nanoparticle-doped zeolites as efficient and versatile materials for water remediation endeavors.

Synergistic efficacy of ZnO quantum dots, Ag NPs, and nitazoxanide composite against multidrug-resistant human pathogens as new trend of revolutionizing antimicrobial treatment

Antibiotic resistance is currently becoming a more serious threat to global health, especially in severe nosocomial infections treatment by multidrug-resistant bacteria. This research provides a new way of synergizing green-synthesis for zinc oxide quantum dots (ZnO-QDs with hexagonal crystals) that are 7 nm in diameter and zero-valent Ag cubic crystals that are 67 nm in size embedded with nitazoxanide substrate (NAZ). Instrumental characterization like SEM, TEM, EDAX, and FT-IR and comprehensive antimicrobial studies were conducted to study the incorporation behavior of composites based on Ag NPs/ZnO QDs/NAZ. This combination has not been hitherto addressed anywhere else in the published literature, as well as commercial viability. In this context, we have precisely tuned nanoparticle to nitazoxanide ratio for designing the formulation demonstrating potent activity against MDR infections. By employing nitazoxanide as a scaffold and careful decoration thereof antimicrobial potency has been unlocked overriding conventional therapies. In addition, Ag NPs/ZnO-QDs/nitazoxanide (G6) formula exhibited a therapeutic efficacy span of 96.15 ± 1.68% to 99.57 ± 0.20% against MDR human infections post 48 h incubation; a breakthrough in therapeutic efficacy levels has been achieved by our method. Accordingly, ZnO QDs/Ag NPs/NAZ composite offered potential multidrug resistant human pathogens as a new trend of revolutionizing antimicrobial treatment.

Biosynthesis of ZnO nanoparticles using aqueous extracts of Eclipta prostrata and Piper longum: characterization and assessment of their antioxidant, antibacterial, and photocatalytic properties

Chemical syntheses of nanoparticles that release toxic substances into the environment rarely meet the strict requirements of green chemistry principles. Instead, green synthesis of nanoparticles using plant extracts brings a safe, rapid, and effective process, contributing to solving environmental pollution problems. Here, we report the green synthesis of multifunctional ZnO nanoparticles (ZnONPs) using aqueous extracts of E. prostrata leaves and P. longum fruits. The XRD results affirmed the existence of hexagonal crystalline ZnONPs with particle sizes of 17-30 nm. The optical analysis revealed bandgap energies of 3.10 eV and 3.16 eV for ZnONPs biosynthesized using E. prostrata and P. longum extracts, respectively. The synthesized ZnONPs showed potential antioxidant activity through DPPH and ABTS methods. Among the antibacterial outcomes against pathogenic bacterial strains (S. aureus, B. cereus, E. coli, and S. typhimurium), ZnONPs exhibited the highest zone of inhibition (18.5 mm) for S. aureus. Moreover, both ZnONPs biosynthesized using E. prostrata and P. longum extracts served as strong photocatalysts in the degradation of crystal violet with degradation efficiencies of 95.64% and 99.90%, respectively. Therefore, biosynthesized ZnONPs hold significant promise as antioxidants, antibacterial agents, and photocatalysts.

Green synthesis of zinc oxide nanoparticles using Rhus coriaria extract and their anticancer activity against triple-negative breast cancer cells

The growing interest in using plant extracts for the biogenic synthesis of zinc oxide nanoparticles (ZnO NPs) stems from their facile, eco-friendly, and biologically safe approach instead of chemical routes. For the first time, ZnO NPs were successfully biosynthesized using Rhus coriaria fruit aqueous extract as a reducing and capping agent. Characterization revealed that the biosynthesized ZnO NPs possessed a maximum absorbance of approximately 359 nm and closely resembled the hexagonal ZnO wurtzite crystalline structure, with an average crystalline size of 16.69 nm. The transmission electron microscope (TEM) showed the presence of spherical and hexagonal morphologies, with an average grain size of 20.51 ± 3.90 nm. Moreover, the elemental composition of the synthesized ZnO NPs was assessed via energy-dispersive X-ray spectrometry (EDX), and the presence of phytocompounds on their surface was subsequently verified through FT-IR analysis. The ζ-potential of ZnO NPs was recorded at - 19.9 ± 0.1663 mV. Regarding anti-cancer properties, ZnO NPs were found to possess potent anti-tumor effects on MCF-7 and MDA-MB-231 breast cancer cells. Their efficacy was dose-dependent, with IC50 values ranging from 35.04-44.86 μg/mL for MCF-7 and 55.54-63.71 µg/mL for MDA-MB-231 cells. Mechanistic studies in MDA-MB-231 cells revealed apoptosis induction, validated by DAPI staining, confocal microscopy, and Annexin V/PI staining, showing apoptosis by 12.59% and 81.57% at ½ IC50 and IC50 values, respectively. Additionally, ZnO NPs were observed to provoke S-phase arrest and inhibit colony-forming and metastatic potential by modulating apoptosis and metastasis-related genes. This study unravels new insights into how ZnO NPs provoke cancer cell death and inhibit metastasis, revealing new prospects in cancer nanotechnology.

Surface modification of jute-cotton union fabric using TiO2 and ZnO nanoparticles for multifunctional properties

In this study TiO2 and ZnO nanoparticles were employed as a protective coating to impart multifunctional properties, i.e. self-cleaning, water repellency, UV protection and antimicrobial activity onto jute-cotton union fabric. Through the sol-gel method, using titanium (IV) isopropoxide (TTIP) and zinc acetate as precursors, TiO2 and ZnO nanoparticles have been synthesized. Following the dip-pad-dry-cure method along with a 2 wt% of acrylic binder, the synthesized particles were applied on the jute-cotton union fabric. Subsequently, antibacterial activity, self-cleaning properties and physical properties like water absorbency, crease recovery, water vapor permeability, tensile strength, and tear strength of the treated fabric were tested and evaluated. The structural properties of the nano-particles were distinguished by Fourier Transform Infrared Spectroscopy (FTIR) and SEM. Upon comparing the test results of the coated fabric with the uncoated fabric, the results were found to be extremely satisfactory. This study provided valuable insights into the potential of TiO2 and ZnO coating in enhancing properties of jute-cotton union fabric.

Coconut husk-lignin derived carbon dots incorporated carrageenan based functional film for intelligent food packaging

Carbon dots (CDs) derived from sustainable natural feed-stocks like lignin have gained wide acceptance by virtue of their renewability and promising potential in intelligent sensing applications. The precursor lignin is isolated from agro-biomass waste, coconut husk through sodium hydroxide based extraction process. CDs are synthesised from amine functionalized lignin through solvothermal process and integrated into carrageenan biopolymer matrix (1, 2 and 3 wt%). The composite film with 2 wt% CDs (CARR2CD) showed optimum fluorescent emission intensity, excellent pH dependent fluorescent color change in the food pH range, reasonable tensile strength (46.50 ± 1.32 MPa) and 27 % increase in elongation at break. CDs imparted UV-light blocking properties (70 % UV-light) and enhanced hydrophobicity of the carrageenan matrix. CARR2CD film showed 84 % visible light transparency, 79 % reduction in oxygen transmittance rate (OTR), 81 % reduction in CO2 gas permeability and excellent antioxidant and antibacterial properties (against E. coli and S. aureus). As a practical application, the developed responsive packaging material is used to track pH change associated with milk spoilage via noticeable color change in fluorescent emission of the composite film. Thus, the developed responsive composite film paves a way for use as green and sustainable transparent intelligent food packaging material.