Psidium guajav-mediated zinc oxide nanoparticles as a multifunctional, microbicidal, antioxidant and antiproliferative agent against destructive pathogens.

Antioxidant, antimicrobial, and photocatalytic activity of green synthesized ZnO-NPs from Myrica esculenta fruits extract

The rapid emergence of multidrug‐resistant (MDR) pathogens, particularly in hospital wastewater, poses a serious threat to public health and emphasizes the need for alternative antimicrobial strategies. In this study, Enterococcus hirae, an environmentally derived strain, was used for the first time in the extracellular green synthesis of zinc oxide nanoparticles (ZnO NPs) and copper oxide/zinc oxide nanoparticles (CuO/ZnO NPs). The nanoparticles were characterized using standard techniques. Ultraviolet–visible (UV‐Vis) spectra, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), and energy‐dispersive X‐ray spectroscopy (EDS) confirmed both nanoparticle formation, size, and morphology. Antimicrobial activity against Staphylococcus aureus (ATCC 6538), Morganella morganii, Kerstersia gyiorum, and Klebsiella pneumoniae was evaluated using minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays, showing a 62.5% greater efficacy of bimetallic NPs than ZnO alone. The 2,2‐diphenyl‐1‐picrylhydrazyl hydrate (DPPH) assay revealed that E‐CuO/ZnO NPs exhibited superior antioxidant activity with the lowest IC50 of 5.528 μg/mL, outperforming E‐ZnO NPs, which is attributed to the synergistic effect between ZnO and CuO NPs. The combination of E‐ZnO and E‐CuO/ZnO nanoparticles with ciprofloxacin (CIP) and ceftazidime (CAZ) was evaluated against MDR isolates. Synergistic interactions were observed particularly against K. pneumoniae. This study confirms effective E. hirae‐mediated synthesis and the enhanced antibacterial and antioxidant potential of CuO/ZnO NPs, supporting eco‐friendly strategies against MDR infections, with synergistic interactions observed with conventional antibiotics, particularly against K. pneumoniae, indicating that the nanoparticles can enhance antibiotic efficacy.

In recent years, there has been a significant focus on the green synthetization of metal oxide nanoparticles due to their environmentally friendly features and cost-effectiveness. The aim of this study is to biosynthesize zinc oxide nanoparticles (ZnO NPs) through a green method, utilizing crude banana peel extract as reducing and capping agents, to characterize the synthesized ZnO NPs and test their antibacterial activity. ZnO NPs were biosynthesized using the peel extract of banana with various concentrations of zinc acetate dihydrate salt, followed by annealing at 400 °C for 2 h. The synthesized ZnO NPs were characterized using UV–visible spectroscopy (UV-Vis), scanning electron microscopy (SEM), dynamic light scattering (DLS), attenuated total reflectance–Fourier-transform infrared (ATR-FTIR), and X-ray diffraction (XRD). Also, its antibacterial efficiency against different bacterial strains was tested. ZnO NPs were biosynthesized successfully using the extract of Musa Acumniata (cavendish) fruit peel with a UV-Vis wavelength range of 344 to 369 nm and an electrical band gap ranging from 3.36 to 3.61 eV. The size varied from 27 ± 4 nm to 89 ± 22, and the negative zeta potential (ζ) ranged from −14.72 ± 0.77 to −7.43 ± 0.35 mV. ATR-FTIR analysis showed that the extract phytochemical functional groups were present on ZnO NPs. XRD results confirm the formation of a highly pure wurtzite hexagonal structure of ZnO NPs. Moreover, the best obtained size of ZnO NPs was selected for the antibacterial tests, giving the highest inhibition growth rate against Staphylococcus epidermidis (98.6 ± 0.9%), while the lowest rate was against Pseudomonas aeruginosa (88.4 ± 4.4%). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were reported and compared to previous studies. The unique properties of greenly synthesized ZnO NPs and their antibacterial activity have potential for reducing environmental pollution and the use of antibiotics, which may contribute to solving the problem of bacterial resistance. Therefore, studies that aim to design an applicable dosage form loaded with biosynthesized ZnO NPs might be conducted in the future.

Green synthesis of zinc oxide nanoparticles using Catharanthus pusillus: Characterization, antibacterial, cytotoxicity of A549 cells, and photocatalytic degradation of Eosin (E) dye

Green synthesis, characterization and antimicrobial activities of zinc oxide nanoparticles from the leaf extract of Azadirachta indica (L.)

In this study, green synthesis methods were employed to fabricate zinc oxide nanoparticles (ZnONPs) using Newbouldia laevis leaves plant extract. Several analytical methods, including Fourier-Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Transmission Electron Microscopy (TEM), and UV-Vis spectrophotometer, were used to characterise the green synthesised ZnONPs. The synthesis of ZnONPs with distinct properties was successfully demonstrated by the structural and morphological investigations. The existence of functional groups involved in the stabilisation and reduction of the nanoparticles was established by FTIR. The shape of the nanoparticles was revealed by TEM. It produced non-spherical particles with a well-defined size distribution, a crystalline structure with a hexagonal shape morphology, and an average nanoparticle size of 34.8 nm. The ZnONPs that were green-synthesised demonstrated unique antioxidant characteristics. The findings showed that the ZnONPs’ capacity to scavenge radicals increased in a concentration-dependent manner. Excellent antifungal activities against Trichophyton rubrum, Aspergilus fumigatus, and Candida albicans were also demonstrated by the synthesised ZnONPs. This suggests that at 100, 200, and 400 mg/mL, the environmentally friendly ZnONPs show inhibitory zones that range from 9 to 18 mm. The use green synthesized ZnO NPs have shown excellent antifungal, antioxidant and photocatalytic reduction of 4-nitrophenol under sunlight. Green synthesis, zinc oxide nanoparticles, 4-ntrophenol, Trichophyton rubrum.

The present research focused on the green, non-toxic, low-cost synthesis of zinc oxide nanoparticles (ZnO NPs) using aqueous extract of Hibiscus tiliaceus leaves as a reducing and stabilizing agent. Thus, synthesized ZnO NPs were characterized by nanotechnological applications, i.e., ultraviolet-visible spectroscopy (UV-vis), dynamic light scattering (DLS), zeta potential, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and high-resolution transmission electron microscopy (HR-TEM). The nanotechnological applications showed that as-synthesized ZnO NPs have bandgap energy of 2.97 eV, zeta potential of −1.2 mV, crystalline in nature (JCPDS data card no-89-1397), and an average size of 30 to 60 nm. The FTIR showed that ZnO NPs have coated with plant secondary metabolites and assisted in the process of green synthesis. The ZnO NPs exhibited broad-spectrum antibacterial activity on Gram-positive and Gram-negative bacteria. The ZnO NPs showed potential anticancer activity against human breast cancer cells MCF-7 and determined the IC50 value as 65.83 ± 2.57 µg/mL by MTT assay. Furthermore, ZnO NPs were used as nano-catalyst for dye degradation of methylene blue, methyl orange, and malachite green with NABH4 as a reducing agent. The ZnO NPs exhibited potent dye degradation capability and followed pseudo-first order kinetics. The study concluded that ZnO NPs could be highly useful as anticancer and antibacterial agents in the biomedical field, and as an environmental cleaning agent for dye degradation in textile industries.

The fabrication of zinc oxide nanoparticles is a concept since zinc oxide nanoparticles can effectively cling onto things that it reacts to light and zinc oxide nanoparticles do not pose any threat to the environment. This paper prepared zinc oxide nanoparticles through a technique known as controlled precipitation and ultimately we monitored the appearance of zinc oxide nanoparticles as well as the process through which zinc oxide nanoparticles were prepared. We then cleaned the water with the use of these zinc oxide nanoparticles with a particular aim of eliminating metals, such as lead, cadmium and chromium. ZnO is very reactive and it has a surface area. This implies that ZnO is able to capture the metals and degrade them thereby decreasing the metal ions in the water. This informs us that ZnO nanoparticles may be a viable approach towards cleaning heavy metals in factory wastewater. This will ensure that it is safer to the environment. Some of the resources can be recovered. ZnO nanoparticles are a water cleaning material and heavy metal recovery material. ZnO nanoparticles are able to clean the water and render it safer. At this, ZnO nanoparticles are truly good. In this paper, the researcher examines how Zinc Oxide Nanoparticles can be prepared e.g. through chemical precipitation, sol-gel and green synthesis. It identifies the good and bad things regarding each of these approaches to the production of Zinc Oxide Nanoparticles. Another aspect that the paper discusses is the application of Zinc Oxide Nanoparticles in water treatment. As an example, Zinc Oxide Nanoparticles have the ability to pick pollutants. It is possible to disperse them with light and filter them. We also talk of getting metals back using Zinc Oxide Nanoparticles. Some techniques such as adsorption-desorption and electrochemical recovery can be applied to the Zinc Oxide Nanoparticles to retrieve the metals back. ZnO NPs are a good method of treating water and recovering heavy metals. ZnO NPs are quite effective in the treatment of water. Removing the heavy metals since they possess some good qualities. The paper discusses the latest development of ZnO NPs such as how to make them easily, eco-friendly, and how ZnO NPs are used to trap harmful compounds in the water using sunshine to dissipate them and using ZnO NPs to filter the water by using ZnO NPs. ZnO NPs prove to be great in the elimination of metals. We can also apply such techniques as adsorption-desorption or electrochemical recovery to recover metals using ZnO NPs. ZnO NPs is a cheap method of purifying water and recover heavy metals. The most pleasant thing is the fact that the ZnO NPs can be utilized on a scale without damaging the environment. ZnO NPs are a cleaning and retrieving heavy metals back solution to water using ZnO NPs. KEY WORDS: Cardamom, Aloe vera, Zinc nitrate hexahydrate, wastewater treatment, lead, UV visible spectroscopy, FTIR, XRD, SEM / TEM.

Zinc oxide nanoparticles (ZnO NPs) were synthesized by Carica papaya leaf extract. The nanoparticles were characterized by UV–Vis spectrum, Fourier Transform Infrared spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic light scattering (DLS) analyser and Energy-dispersive X-ray spectroscopy analysis with a scanning electron microscope (SEM–EDX). The ZnO NPs were assessed using 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay with varying ZnO NP concentration, showed scavenging activity with the half maximal inhibitory concentration (IC50) = 130.1 and 104.9 µg/mL−1 respectively. Antifungal studies were conducted for ZnO NPs against S. sclerotiorum, R. necatrix and Fusarium species, which demonstrated a higher inhibition rate for S. sclerotiorum (59.7%). Seeds of chickpea were separately treated with various concentrations of ZnO NPs. An exposure to ZnO NPs (25%, 50%, 75% and 100%) and control caused significant changes in seed germination, root length, shoot length and antioxidant enzyme were studied. Compared with control the maximum seed germination, root and plant growth was observed with the treatment of ZnO NPs. Superoxide dismutase and catalase activity increased due to ZnO NPs treatment. This suggest that ZnO NPs may significantly alter antioxidant metabolism during seed germination.

The green synthesis of zinc oxide nanoparticles (ZnO-NPs) using plant extracts is an eco-friendly and economical process compared with existing methods. The present investigation utilized the leaf and seed extracts of Croton macrostachyus Hochst. ex Delile to biosynthesize ZnO-NPs using a green technique with zinc acetate as the precursor at 80 °C for 60 minutes. XRD analysis proved the hexagonal structure of the Wurtzite ZnO-NPs, with average crystallite dimensions of approximately 40 nm. The estimated band gaps using UV-Visible spectroscopy were in the range of 3.17–3.19 eV, and FTIR, SEM, XPS, and EDS studies proved the functional groups and element contents of ZnO-NPs, in which trace levels of Ca and Mg were present in the extracts. The ZnO-NPs derived from the green synthesis method displayed high antibacterial efficacy against Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa and Klebsiella pneumoniae, which surpassed the antibacterial efficacy of the crude extracts. The green synthesis of ZnO NPs using Croton macrostachyus extracts thus presents promising results in relation to their possible antibacterial applications in the biomedical field and green nanotechnology.

Controlled synthesis of zinc oxide nanoparticles through flame spray pyrolysis and evaluation of their anticancer effects against gastric cancer cell

Facile green synthesis of zinc oxide nanoparticles by Eucalyptus globulus and their photocatalytic and antioxidant activity

The high incidence of fungal resistance to antifungal drugs represents a global concern, contributing to high levels of morbidity and mortality, especially among immunocompromised patients. Moreover, conventional antifungal medications have poor therapeutic outcomes, as well as possible toxicities resulting from long-term administration. Accordingly, the aim of the present study was to investigate the antifungal effectiveness of biogenic zinc oxide nanoparticles (ZnO NPs) against multidrug-resistant candidal strains. Biogenic ZnO NPs were characterized using physicochemical methods, such as UV-vis spectroscopy, transmission electron microscopy (TEM), energy-dispersive X ray (EDX) spectroscopy, FTIR (Fourier transform infrared) spectroscopy and X-ray powder diffraction (XRD) analysis. UV spectral analysis revealed the formation of two absorption peaks at 367 and 506 nm, which preliminarily indicated the successful synthesis of ZnO NPs, whereas TEM analysis showed that ZnO NPs exhibited an average particle size of 22.84 nm. The EDX spectrum confirmed the successful synthesis of ZnO nanoparticles free of impurities. The FTIR spectrum of the biosynthesized ZnO NPs showed different absorption peaks at 3427.99, 1707.86, 1621.50, 1424.16, 1325.22, 1224.67, 1178.22, 1067.69, 861.22, 752.97 and 574.11 cm−1, corresponding to various functional groups. The average zeta potential value of the ZnO NPs was −7.45 mV. XRD analysis revealed the presence of six diffraction peaks at 2θ = 31.94, 34.66, 36.42, 56.42, 69.54 and 76.94°. The biogenic ZnO NPs (100 µg/disk) exhibited potent antifungal activity against C. albicans, C. glabrata and C. tropicalis strains, with suppressive zone diameters of 24.18 ± 0.32, 20.17 ± 0.56 and 26.35 ± 0.16 mm, respectively. The minimal inhibitory concentration (MIC) of ZnO NPs against C. tropicalis strain was found to be 10 μg/mL, whereas the minimal fungicidal concentration (MFC) was found to be 20 μg/mL. Moreover, ZnO NPs revealed a potential synergistic efficiency with fluconazole, nystatin and clotrimazole antifungal drugs against C. albicans strain, whereas terbinafine, nystatin and itraconazole antifungal drugs showed a potential synergism with ZnO NPs against C. glabrata as a multidrug-resistant strain. In conclusion, pomegranate peel extract mediated green synthesis of ZnO NPs with potential physicochemical features and antimicrobial activity. The biosynthesized ZnO NPs could be utilized for formulation of novel drug combinations to boost the antifungal efficiency of commonly used antifungal agents.

Green synthesis of zinc oxide nanoparticles using novel bacterium strain (Bacillus subtilis NH1-8) and their in vitro antibacterial and antibiofilm activities against Salmonellatyphimurium

Green synthesis of metal oxide nanoparticles using plant extracts offers an eco-friendly and sustainable approach for developing effective photocatalysts for environmental remediation. The present study reports the green synthesis of zinc oxide nanoparticles (ZnO NPs) using aqueous fruit extract of Manilkara zapota as a reducing and stabilising agent, with zinc nitrate as the precursor salt. The synthesised nanoparticles were characterised using Fourier Transform Infrared Spectroscopy (FT-IR), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Analysis (EDX), and X-ray Diffraction (XRD). FT-IR analysis revealed the presence of hydroxyl, amine, carbonyl, and alkyl functional groups involved in nanoparticle formation and stabilisation. FESEM micrographs showed predominantly spherical nanoparticles with slight agglomeration and an average particle size of approximately 35 nm. EDX analysis confirmed the elemental composition of zinc and oxygen, while XRD patterns verified the crystalline wurtzite structure of ZnO with an average crystallite size of 26.99 nm. The antioxidant potential of the nanoparticles was evaluated using the DPPH free radical scavenging assay and demonstrated appreciable antioxidant activity. Furthermore, the photocatalytic performance of the ZnO nanoparticles was assessed using methylene blue dye as a model pollutant under xenon lamp irradiation. The nanoparticles exhibited significant dye degradation efficiency, with degradation increasing progressively with irradiation time. The enhanced photocatalytic activity was attributed to the nanoscale size, high surface area, and abundance of active catalytic sites. The study demonstrates that Manilkara zapota-mediated ZnO nanoparticles are environmentally friendly, cost-effective, and promising materials for wastewater treatment and environmental remediation applications.