Search Results (15)

The present study aimed to evaluate the impact of varying dietary concentrations of calcium oxide nanoparticles (CaO-NPs) on important health regulators in Zebra fish (Danio rerio) using integrative physiological, histopathological, and computational approaches. The co-precipitation method was used to synthesize NPs and characterization was performed through DLS, XRD, FESEM, EDX, and FTIR depicting spherical-shaped CaO-NPs with a hydrodynamic diameter of 91.2 nm. Adult Danio rerio were administered with three different feed regimes enriched with 2.4 (T1), 1.6 (T2), and 0.8 (T3) mg CaO-NPs/kg for 30 days. Growth, survival, NP accumulation, and histological assessments, and bioinformatic studies, were performed to understand interactions of NPs with fish metabolic proteins. The T3 group demonstrated the highest survival (75%) and weight gain (+39.31%), and exhibited the lowest accumulation of CaO-NPs in the brain (0.133 mg/L), liver (0.642 mg/L), and intestine (0.773 mg/L) with no evident histological alterations, whereas T1 group exhibited major liver and intestinal damage. Molecular docking targeting the NRF-2 oxidative stress pathway revealed strong binding affinities of NPs with catalase (−3.7), keap1a (−3.5), keap1b (−3.3), and mafk (−2.4), highlighting potential modulation of redox homeostasis. Hence, a 0.8mg CaO-NPs/kg feed dose is recommended to promote potential health benefits in Danio rerio, which can be further applicable to commercial aquaculture for enhanced fish health while minimizing toxicity. Full article

Among the new strategies for managing diseases in agricultural crops is the application of metallic nanoparticles due to their ability to inhibit the development of phytopathogenic microorganisms and to induce plant defense responses. Therefore, this research evaluated the effects of silver (AgNPs), zinc oxide (ZnONPs), and silicon dioxide (SiO₂NPs) nanoparticles on symptom progression and physiological parameters in two pathosystems: Pseudomonas syringae pv. tomato (Psto) in tomato (pathosystem one, culturable pathogen) and Candidatus Liberibacter solanacearum (CaLso) in pepper plants (pathosystem two, non-culturable pathogen). For in vitro pathosystem one assays, SiO₂NPs did not inhibit Psto growth. The minimum inhibitory concentration (MIC) was 31.67 ppm for AgNPs and 194.3 ppm for ZnONPs. Furthermore, the minimum lethal concentration (MLC) for AgNPs was 100 ppm, while for ZnONPs, it was 1000 ppm. For in planta assays, ZnONPs, AgNPs, and SiO₂NPs reduced the number of lesions per leaf, but only ZnONPs significantly decreased the severity. Regarding pathosystem two, AgNPs, ZnONPs, and SiO₂NPs application delayed symptom progression. However, only AgNPs significantly reduced severity percentage. Moreover, treatments with AgNPs and SiO₂NPs increased the plant height and dry weight compared to the results for the control. Full article

This study introduces a novel paper coating approach using modified zinc oxide (ZnO), providing a comparison with conventional materials used in the paper industry. The research focused on determining the concentration for effective microbial growth inhibition and evaluates the impact of different ZnO types on coated-paper properties, including antimicrobial activity, surface morphology, tensile strength, and water absorption. Specifically, ZnO microparticles (ZnO_ws), ZnO nanoparticles (ZnO_np), and modified ZnO_np (ZnO_np-CaCO₃, with a core–shell structure composed of calcium carbonate [CaCO₃] and nano-zinc oxide) were incorporated into coating formulations at varying concentrations (0 × MIC, 1 × MIC, 2 × MIC, and 3 × MIC, based on minimum inhibitory concentrations [MICs]). The results demonstrated that among all tested microorganisms, ZnO_np-CaCO₃ showed the lowest MIC values. ZnO_np-CaCO₃-coated paper exhibited superior antimicrobial activity against both Gram-positive and Gram-negative bacteria, as well as fungi, outperforming ZnO_ws and ZnO_np. At 1 × MIC, %inhibition for E. coli, S. aureus, and A. niger were 98.3%, 99.1%, and 90.8%, respectively. Additionally, ZnO_np-CaCO₃ coatings caused minimal color change in the paper compared to the other ZnO variants. The coating did not negatively impact the mechanical properties of the paper across all ZnO types and concentrations. Water absorption tests showed increased hydrophobicity with higher ZnO content, with ZnO_np and ZnO_np-CaCO₃ exhibiting greater reductions in water absorption than ZnO_ws. Overall, ZnO_np-CaCO₃ showed strong potential as an antimicrobial agent for paper surfaces, making it ideal for packaging and hygiene products. By partially replacing ZnO_np with inexpensive CaCO₃ core particles, ZnO_np-CaCO₃ delivers enhanced performance, reduced costs, and greater sustainability for large-scale applications. Full article

Green peppers (Capsicum annuum L.) are a fruit vegetable with great culinary versatility and present important nutritional properties for human health. Water deficit negatively affects the nutritional quality of green peppers’ fruits. This study aimed to investigate the influence of zinc oxide nanoparticles (ZnONPs), associated with plant growth-promoting bacteria (PGPB), on the post-harvest nutritional quality of green peppers subjected to water deficit. In an open-field experiment, two irrigation levels (50 and 100% of crop evapotranspiration (Etc)), four treatments composed of a combination of ZnONPs, zinc sulfate (ZnSO₄), and PGPB (T1 = ZnSO₄ via leaves, T2 = ZnONPs via leaves, T3 = ZnONPs via leaves + PGPB via soil, T4 = ZnSO₄ via soil + PGPB via soil), and a control treatment (Control) were tested. Water deficit or water deficit mitigation treatments did not interfere with the physical–chemical parameters (except vitamin C content) and physical color parameters (except the lightness) of green peppers. On average, the water deficit reduced the levels of Ca (−13.2%), Mg (−8.5%), P (−8.5%), K (−8.6%), Mn (−10.5%), Fe (−12.2%), B (−12.0%), and Zn (−11.5%) in the fruits. Under the water deficit condition, ZnONPs or ZnSO₄ via foliar, associated or not with PGPB, increased the levels of Ca (+57% in the T2 and +69.0% in the T2), P, Mg, and Fe in the fruits. At 50% Etc, the foliar application of ZnONPs in association with PGPB increases vitamin C and mineral nutrients’ contents and nutritional quality index (+12.0%) of green peppers. Applying Zn via foliar as ZnONPs or ZnSO₄ mitigated the negative effects of water deficit on the quality of pepper fruits that were enhanced by the Bacillus subtilis and B. amyloliquefaciens inoculation. The ZnONPs source was more efficient than the ZnSO₄ source. The water deficit alleviating effect of both zinc sources was enhanced by the PGPB. Full article

The demand for lithium is constantly increasing due to its wide range of uses in an excessive number of industrial applications. Typically, expensive lithium-based chemicals (LiOH, LiCl, LiNO₃, etc.) have been used to fabricate adsorbents (i.e., lithium manganese oxide) for lithium ion (Li⁺) adsorption from aqueous sources. This type of lithium-based adsorbent does not seem to be very effective in recovering Li⁺ from water from an economic point of view. In this study, an innovative nanocomposite for Li⁺ adsorption was investigated for the first time, which eliminates the use of lithium-based chemicals for preparation. Here, calcium oxide nanoparticles (CaO-NPs), silver-doped CaO nanoparticles (Ag-CaO-NPs), and surfactant (polyvinylpyrrolidone (PVP) and sodium dodecyl sulfate (SDS))-modified Ag-CaO (PVP@Ag-CaO and SDS@Ag-CaO) nanocomposites were designed by the chemical co-precipitation method. The PVP and SDS surfactants acted as stabilizing and capping agents to enhance the Li⁺ adsorption and recovery performance. The physicochemical properties of the designed samples (morphology, size, surface functionality, and crystallinity) were also investigated. Under optimized pH (10), contact time (8 h), and initial Li⁺ concentration (2 mg L⁻¹), the highest Li⁺ adsorption efficiencies recorded by SDS@Ag-CaO and PVP@Ag-CaO were 3.28 mg/g and 2.99 mg/g, respectively. The nature of the Li⁺ adsorption process was examined by non-linear kinetic and isothermal studies, which revealed that the experimental data were best fit by the pseudo-first-order and Langmuir models. Furthermore, it was observed that the SDS@Ag-CaO nanocomposite exhibited the highest Li⁺ recovery potential (91%) compared to PVP@Ag-CaO (85%), Ag-CaO NPs (61%), and CaO NPs (43%), which demonstrates their regeneration potential. Therefore, this type of innovative adsorbents can provide new insights for the development of surfactant-capped nanocomposites for enhanced Li⁺ metal recovery from wastewater. Full article

The significance of nanomaterials in biomedicines served as the inspiration for the design of this study. In this particular investigation, we carried out the biosynthesis of calcium oxide nanoparticles (CaONPs) by employing a green-chemistry strategy and making use of an extract of Ficus carica (an edible fruit) as a capping and reducing agent. There is a dire need for new antimicrobial agents due to the alarming rise in antibiotic resistance. Nanoparticles’ diverse antibacterial properties suggest that they might be standard alternatives to antimicrobial drugs in the future. We describe herein the use of a Ficus carica extract as a capping and reducing agent in the phyto-mediated synthesis of CaONPs for the evaluation of their antimicrobial properties. The phyto-mediated synthesis of NPs is considered a reliable approach due to its high yield, stability, non-toxicity, cost-effectiveness and eco-friendliness. The CaONPs were physiochemically characterized by UV-visible spectroscopy, energy-dispersive X-ray (EDX), scanning-electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). The biological synthesis of the calcium oxide nanoparticles revealed a characteristic surface plasmon resonance peak (SPR) at 360 nm in UV-Vis spectroscopy, which clearly revealed the successful reduction of the Ca²⁺ ions to Ca⁰ nanoparticles. The characteristic FTIR peak seen at 767 cm⁻¹ corresponded to Ca-O bond stretching and, thus, confirmed the biosynthesis of the CaONPs, while the scanning-electron micrographs revealed near-CaO aggregates with an average diameter of 84.87 ± 2.0 nm. The antibacterial and anti-biofilm analysis of the CaONPs showed inhibition of bacteria in the following order: P. aeruginosa (28 ± 1.0) > S. aureus (23 ± 0.3) > K. pneumoniae (18 ± 0.9) > P. vulgaris (13 ± 1.6) > E. coli (11 ± 0.5) mm. The CaONPs were shown to considerably inhibit biofilm formation, providing strong evidence for their major antibacterial activity. It is concluded that this straightforward environmentally friendly method is capable of synthesizing stable and effective CaONPs. The therapeutic value of CaONPs is indicated by their potential as a antibacterial and antibiofilm agents in future medications. Full article

The challenges in the production of metabolites of medicinal potential from wild plants include low yields, slow growth rates, seasonal variations, genetic variability and regulatory as well as ethical constraints. Overcoming these challenges is of paramount significance and interdisciplinary approaches and innovative strategies are prevalently applied to optimize phytoconstituents’ production, enhance yield, biomass, ensure sustainable consistency and scalability. In this study, we investigated the effects of elicitation with yeast extract and calcium oxide nanoparticles (CaONPs) on in vitro cultures of Swertia chirata (Roxb. ex Fleming) Karsten. Specifically, we examined the effects of different concentrations of CaONPs in combination with different concentrations of yeast extract on various parameters related to callus growth, antioxidant activity, biomass and phytochemical contents. Our results showed that elicitation with yeast extract and CaONPs had significant effects on the growth and characteristics of callus cultures of S. chirata. The treatments involving yeast extract and CaONPs were found to be the most effective in increasing the contents of total flavonoid contents (TFC), total phenolic contents (TPC), amarogentin and mangiferin. These treatments also led to an improvement in the contents of total anthocyanin and alpha tocopherols. Additionally, the DPPH scavenging activity was significantly increased in the treated samples. Furthermore, the treatments involving elicitation with yeast extract and CaONPs also led to significant improvements in callus growth and characteristics. These treatments promoted callus response from an average to an excellent level and improved the color and nature of the callus from yellow to yellow-brown and greenish and from fragile to compact, respectively. The best response was observed in treatments involving 0.20 g/L yeast extract and 90 ug/L CaONPs. Overall, our findings suggest that elicitation with yeast extract and CaONPs can be a useful strategy for promoting the growth, biomass, phytochemical contents and antioxidant activity of callus cultures of S. chirata in comparison to wild plant herbal drug samples. Full article

This research analyzed the dispersion and impact of magnesium oxide nanoparticles (MgONPs) varnish on inhibiting enamel demineralization. A novel MgONPs varnish was prepared in absolute ethanol with rosin in 10%, 5%, 2.5%, and 1.25% concentrations. The samples were classified into six groups, including four tested with MgONPs varnish, one commercial 5% NaF varnish, and control groups of non-protected and sound dental enamel groups. Each group included five enamel samples and three broths of 20 mL per sample. The examinations were started by applying different concentrations of varnishes on the enamel surfaces, which were then exposed to Streptococcus mutans (S. mutans) in three sequences of time for 144 h. A scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to examine the MgONPs’ dispersion. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to quantify the calcium (Ca) released from the enamel. The SEM and EDX evaluations of the enamel samples showed a significantly increased dispersion for the 5% MgONPs varnish, with the highest median. The ICP-OES test showed significant inhibition levels of the Ca release capacity in the 2.5% and 1.25% MgONPs varnishes, similar to the 5% NaF varnish. The MgONPs varnish revealed increasing dispersion of MgONPs, from 1.25% to 5%, and the maximum protection capacity was associated with the 1.25% and 2.5% varnishes, which was similar to the 5% NaF varnish in inhibiting the demineralization effect on enamel. Full article

This paper explores the potential of nano seed priming with calcium oxide nanoparticles in maintaining the redox status in carom (Trachyspermum ammi L.) plants by modulating non-enzymatic antioxidants and enzymatic antioxidants. Calcium oxide nanoparticles were prepared in four testing regimes comprising 25, 50, 75, and 100 ppm along with the control treatment of 0 ppm (distilled water). Priming was performed by soaking the carom seeds in the aerated water, and plants were grown under split plots corresponding to drought and water. Seed priming with 75 ppm CaONPs reduced hydrogen peroxide, malondialdehyde contents and electrolyte leakage by 23.3%, 35.9% and 31.6%, respectively, in the water-stressed carom plants. The glutathione s-transferase, superoxide dismutase and peroxidase functions improved under water stress by 42.3%, 24.1% and 44.8%, respectively, in the carom plants raised through 100 ppm primed seeds with CaO_NPs. Priming induced better Ca²⁺ signaling, which affected the enzymes of the ascorbate glutathione cycle, enabling them to maintain redox status in the carom plants exposed to drought stress. The morpho-agronomic traits of carom plants in terms of number of umbels, hundred seeds weights, shoot and root length and biomass improved significantly upon seed priming treatments. Seed priming with CaO_NPs is a viable strategy to combat reactive oxygen species-mediated damages in the carom plants. Full article

Modern nanotechnology encompasses every field of life. Nowadays, phytochemically fabricated nanoparticles are being widely studied for their bioactivities and biosafety. The present research studied the synthesis, characterization, stability, biocompatibility, and in vitro bioactivities of calcium oxide nanoparticles (CaONPs). The CaONPs were synthesized using Citrullus colocynthis ethanolic fruit extracts. Greenly synthesized nanoparticles had an average size of 35.93 ± 2.54 nm and showed an absorbance peak at 325 nm. An absorbance peak in this range depicts the coating of phenolic acids, flavones, flavonols, and flavonoids on the surface of CaONPs. The XRD pattern showed sharp peaks that illustrated the preferred cubic crystalline nature of triturate. A great hindrance to the use of nanoparticles in the field of medicine is their extremely reactive nature. The FTIR analysis of the CaONPs showed a coating of phytochemicals on their surface, due to which they showed great stability. The vibrations present at 3639 cm⁻¹ for alcohols or phenols, 2860 cm⁻¹ for alkanes, 2487 cm⁻¹ for alkynes, 1625 cm⁻¹ for amines, and 1434 cm⁻¹ for carboxylic acids and aldehydes show adsorption of phytochemicals on the surface of CaONPs. The CaONPs were highly stable over time; however, their stability was slightly disturbed by varying salinity and pH. The dialysis membrane in vitro release analysis revealed consistent nanoparticle release over a 10-h period. The bioactivities of CaONPs, C. colocynthis fruit extracts, and their synergistic solution were assessed. Synergistic solutions of both CaONPs and C. colocynthis fruit extracts showed great bioactivity and biosafety. The synergistic solution reduced cell viability by only 14.68% and caused only 16% hemolysis. The synergistic solution inhibited Micrococcus luteus slightly more effectively than streptomycin, with an activity index of 1.02. It also caused an 83.87% reduction in free radicals. Full article

The aim of this study is the preparation of nanostructured copper(II) oxide-based materials (CuONPs) through a facile additive-free polyol procedure that consists of the hydrolysis of copper(II) acetate in 1,4-butane diol and its application in hydrogen peroxide sensing. The nonenzymatic electrochemical sensor for hydrogen peroxide determination was constructed by drop casting the CuONP sensing material on top of a glassy carbon electrode (GCE) modified by a layer of poly(3,4-ethylenedioxythiophene) conducting polymer (PEDOT). The PEDOT layer was prepared on GCE using the sinusoidal voltage method. The XRD pattern of the CuONPs reveals the formation of the monoclinic tenorite phase, CuO, with average crystallite sizes of 8.7 nm, while the estimated band gap from UV–vis spectroscopy is of 1.2 eV. The SEM, STEM, and BET analyses show the formation of quasi-prismatic microaggregates of nanoparticles, with dimensions ranging from 1 µm up to ca. 200 µm, with a mesoporous structure. The developed electrochemical sensor exhibited a linear response toward H₂O₂ in the concentration range from 0.04 to 10 mM, with a low detection limit of 8.5 μM of H₂O₂. Furthermore, the obtained sensor possessed an excellent anti-interference capability in H₂O₂ determination in the presence of interfering compounds such as KNO₃ and KNO₂. Full article

Melatonin (MEL), an indolamine with diverse functions in the brain, has been shown to produce antidepressant-like effects, presumably through stimulating neurogenesis. We recently showed that the combination of MEL with ketamine (KET), an NMDA receptor antagonist, has robust antidepressant-like effects in mice, at doses that, by themselves, are non-effective and have no adverse effects. Here, we show that the KET/MEL combination increases neurogenesis in a clone derived from human olfactory neuronal precursors, a translational pre-clinical model for effects in the human CNS. Neurogenesis was assessed by the formation of cell clusters > 50 µm in diameter, positively stained for nestin, doublecortin, BrdU and Ki67, markers of progenitor cells, neurogenesis, and proliferation. FGF, EGF and BDNF growth factors increased the number of cell clusters in cultured, cloned ONPs. Similarly, KET or MEL increased the number of clusters in a dose-dependent manner. The KET/MEL combination further increased the formation of clusters, with a maximal effect obtained after a triple administration schedule. Our results show that the combination of KET/MEL, at subeffective doses that do not produce adverse effects, stimulate neurogenesis in human neuronal precursors. Moreover, the mechanism by which the combination elicits neurogenesis is meditated by melatonin receptors, CaM Kinase II and CaM antagonism. This could have clinical advantages for the fast treatment of depression. Full article

Over the past few years, the concern for green chemistry and sustainable development has risen dramatically. Researchers make an effort to find solutions to difficult challenges using green chemical processes. In this study, we use oyster shells as a green chemical source to prepare calcium oxide nanoparticles (CaO-NPs). Transmission electron microscopy (TEM) results showed the CaO-NPs morphology, which was spherical in shape, 40 ± 5 nm in diameter, with uniform dispersion. We further prepared silver/polydopamine/calcium-oxide (Ag/PDA/CaO) nanocomposites as the surface-enhanced Raman scattering (SERS) substrates and evaluated their enhancement effect using the methyl parathion pesticide. The effective SERS detection limit of this method is 0.9 nM methyl parathion, which is much lower than the safety limits set by the Collaborative International Pesticides Analytical Council for insecticide in fruits. This novel green material is an excellent SERS substrate for future applications and meets the goal of green chemistry and sustainable development. Full article

The use of nano-fertilizers and antioxidants for specific crops to minimize the negative effect of abiotic stresses is imperative. Two field experiments were fulfilled during two summer seasons (2019 and 2020) to study the response of sweet potato (Beauregard cv.) plants grown in calcareous soil (CaCO₃ = 10.8–11.3%) to foliar nourishment with zinc oxide nanoparticles (ZnONPs) and ascorbic acid (ASA) applied individually or in a mixture. Both ZnONPs and ASA were applied in three doses: 0, 1000, or 1500 mg L⁻¹ for ZnONPs, and 0, 250 and 500 mg L⁻¹ for ASA. The highest values of iron (Fe) and manganese (Mn) contents were recorded in both seasons, while those of phosphorus (P) and copper (Cu) were recorded in the 2020 season with ZnONPs applied at 1500 mg L⁻¹. Furthermore, in both seasons, the maximum values of nutrient contents, excluding Mn content, were obtained with ASA applied at 500 mg L⁻¹. However, applying both ZnONPs and ASA in a mixture bypassed each applied alone, with the highest overall nutrient contents being recorded, with few exceptions, with the highest dose of the mixture. The trend of the tuber root nutrient contents was correlated with the corresponding values in the leaves. Maximum tuber root yield was obtained with foliar feeding with 1000 mg ZnONP and 250 mg ASA L⁻¹ in both seasons. The resulting data recommend the use of foliar nourishment with fertilizer nanoparticles and antioxidants to enable stressed plants to collect appropriate nutrient contents from the defective soils. Full article

The utility of calcium oxide nanoparticles in the biomedical and physical fields has instigated their biocompatible synthesis and production. Moreover, it is important to investigate their biocompatibility at the molecular level for biomedical and ecotoxicological concern. This study explores the green synthesis of calcium oxide nanoparticles (CaONP) using Crescentia cujete leaf extract. The synthesized CaONP were found to have a size of 62 ± 06 nm and a hydrodynamic diameter of 246 ± 12 nm, as determined by FE-SEM and dynamic light scattering (DLS). CaONP was stable in fish medium with a zeta potential of −23 ± 11 mV. The biocompatibility of the CaONP was investigated with adult zebrafish bearing an LC50 of 86.32 µg/mL. Cellular and molecular investigation revealed the mechanism of biocompatibility as a consequence of elicited reactive oxygen species leading to apoptosis, due to accumulation and internalization of CaONP in exposed zebrafish. The study provided detailed information about the mechanistic biocompatibility and a defined horizon of green synthesis of CaONP for biomedical and ecological purposes. Full article