Phytoassisted synthesis of magnesium oxide nanoparticles with Swertia chirayaita

Synthesis of novel MgO-ZnO nanocomposite using Pluchea indica leaf extract and study of their biological activities

The biosynthesis of bimetallic nanoparticles using plant extracts has garnered significant attention due to their eco-friendly and cost-effective nature. This study aimed to biosynthesize magnesium oxide-zinc oxide nanocomposite (MgO-ZnO nanocomposite) using Pluchea indica leaf extract for the first time, with a focus on characterizing its physicochemical properties and evaluating its biological activities. The biosynthesized MgO-ZnO nanocomposite was fully characterized, revealing an absorbance peak at 300 nm using UV-vis spectroscopy. Transmission electron microscopy (TEM) confirmed particle stability within the size range of 5-35 nm. Cytotoxicity analysis on the Wi 38 normal cell line demonstrated an IC50 value of 179.13 µg/mL, indicating good biosafety. The nanocomposite exhibited potent anticancer activity, with IC50 values of 73.61 µg/mL and 31.25 µg/mL against Hep-G2 and MCF-7 cancer cell lines, respectively. Antibacterial assays revealed activity against Klebsiella pneumoniae, Escherichia coli, Bacillus cereus, Staphylococcus aureus, and Candida albicans, with minimum inhibitory concentrations (MICs) ranging from 31.25 to 250 µg/mL. Furthermore, the nanocomposite displayed antioxidant activity with an IC50 value of 175 µg/mL, as determined by the DPPH assay. In conclusion, the successful synthesis of the MgO-ZnO nanocomposite using P. indica leaf extract demonstrates its potential as a safe and effective agent for concentration-dependent antioxidants, antibacterial, and anticancer applications. This study highlights the versatility of plant-mediated biosynthesis in developing functional nanomaterials for biomedical use.

Biogenic Synthesis of Photosensitive Magnesium Oxide Nanoparticles Using Citron Waste Peel Extract and Evaluation of Their Antibacterial and Anticarcinogenic Potential

Background

Magnesium oxide nanoparticles (MgONPs) have been fabricated by several approaches, including green chemistry approach due to diverse application and versatile features.

Objectives

The current study aimed to prepare a convenient, biocompatible, and economically viable MgONPs using waste citron peel extract (CP-MgONPs) to evaluate their biological applications.

Methods

The CP-MgONPs were synthesized by a sustainable approach from extract of waste citron peel both as capping and reducing agents without use of any hazardous material. The physicochemical features of formed CP-MgONPs were determined by sophisticated analytical and microscopic techniques. The biogenic CP-MgONPs were examined for their antibacterial, anticarcinogenic, and photocatalytic attributes.

Results

A prominent absorption peak in the UV-Vis spectra at 284 nm was the distinguishing characteristic of the CP-MgONPs. The scanning electron microscopy (SEM) reveals polyhedral morphology of nanoparticles with slight agglomeration of CP-MgONPs. The CP-MgONPs exerted excellent antibacterial potencies against six bacterial strains. The CP-MgONPs displayed significant susceptibility towards E. coli (20.72 ± 0.33 mm) and S. aureus (19.52 ± 0.05 mm) with the highest inhibition zones. The anticancer effect of CP-MgONPs was evaluated against HepG2 (IC50 : 15.3 μg·mL-1) cancer cells and exhibited potential anticancer activity. A prompt inversion of cellular injury manifested as impairment of the integrity of the cell membrane, apoptosis, and oxidative stress was observed in treated cells with CP-MgONPs. The biosynthesized CP-MgONPs also conducted successful photocatalytic potential as much as MgO powder under the UV-light using acid orange 8 (AO-8) dye. The degradation performance of CP-MgONPs showed over 94% photocatalytic degradation efficiency of acid orange 8 (AO-8) dyes within a short time.

Conclusions

Outcomes of this research signify that biogenic CP-MgONPs may be advantageous at low concentrations, with positive environmental impacts.

The utility of Hibiscus sabdariffa L. to prepare metal oxides NPs for clinical application on osteoporosis supported by theoretical study

Green synthesis of metal oxides as a treatment for bone diseases is still exploring. Herein, MgO and Fe2O3 NPs were prepared from the extract of Hibiscus sabdariffa L. to study their effect on vit D3, Ca+2, and alkaline phosphatase enzyme ALP associated with osteoporosis. Computational chemistry was utilized to gain insight into the possible interactions. These oxides were characterized by X-ray diffraction, SEM, FTIR, and AFM. Results revealed that green synthesis of MgO and Fe2O3 NPs was successful with abundant. MgO NPs were in vitro applied on osteoporosis patients (n = 35) and showed a significant elevation of vit D3 and Ca+2 (0.0001 > p < 0.001) levels, compared to healthy volunteers (n = 25). Thus, Hibiscus sabdariffa L. is a good candidate to prepare MgO NPs, with a promising enhancing effect on vit D3 and Ca+2 in osteoporosis. In addition, interactions of Fe2O3 and MgO NPs with ALP were determined by molecular docking study.

Magnesium Oxide (MgO) Nanoparticles: Synthetic Strategies and Biomedical Applications

In recent times, there has been considerable interest among researchers in magnesium oxide (MgO) nanoparticles, due to their excellent biocompatibility, stability, and diverse biomedical uses, such as antimicrobial, antioxidant, anticancer, and antidiabetic properties, as well as tissue engineering, bioimaging, and drug delivery applications. Consequently, the escalating utilization of magnesium oxide nanoparticles in medical contexts necessitates the in-depth exploration of these nanoparticles. Notably, existing literature lacks a comprehensive review of magnesium oxide nanoparticles’ synthesis methods, detailed biomedical applications with mechanisms, and toxicity assessments. Thus, this review aims to bridge this gap by furnishing a comprehensive insight into various synthetic approaches for the development of MgO nanoparticles. Additionally, it elucidates their noteworthy biomedical applications as well as their potential mechanisms of action, alongside summarizing their toxicity profiles. This article also highlights challenges and future prospects for further exploring MgO nanoparticles in the biomedical field. Existing literature indicates that synthesized magnesium oxide nanoparticles demonstrate substantial biocompatibility and display significant antibacterial, antifungal, anticancer, and antioxidant properties. Consequently, this review intends to enhance readers’ comprehension regarding recent advancements in synthesizing MgO nanoparticles through diverse approaches and their promising applications in biomedicine.

Differential responses of Brassica napus cultivars to dual effects of magnesium oxide nanoparticles

Magnesium oxide nanoparticles (MgO NPs) have great potential to enhance the crop productivity and sustainability of agriculture. Still, a thorough understanding is lacking about its essentiality or toxicity and precise dose for the safe cultivation of oilseed crops. Thus, we assessed the dual effects of MgO NPs (control, 5, 10, 20, 40, 80, and 200 mg/L) on the seed germination, growth performance, photosynthesis, total soluble protein, total carbohydrates, oxidative stress markers (hydrogen peroxide as H2O2 and superoxide anion as O2•‒), lipid peroxidation as MDA, and antioxidant defence machinery (SOD, CAT, APX, and GR activities, and GSH levels) of seven different oilseeds (Brassica napus L.) cultivars (ZY 758, ZD 649, ZD 635, ZD 619, GY 605, ZD 622, and ZD 630). Our findings revealed that low doses of MgO NPs (mainly at 10 mg/L) markedly boosted the seed germination, plant growth (shoot and root lengths) (15‒22%), and biomass (fresh and dry) (11‒19%) by improving the levels of photosynthetic pigments (14‒27%), net photosynthetic rate, stomatal conductance, photosynthetic efficiency (Fv/Fm), total soluble protein and total carbohydrates (16‒36%), antioxidant defence, and reducing the oxidative stress in B. napus tissues. Among all B. napus cultivars, these beneficial effects of MgO NPs were pronounced in ZD 635. ile, elevated levels of MgO NPs (particularly at 200 mg/L) induced oxidative stress, impaired antioxidant scavenging potential, photosynthetic inhibition, protein oxidation, and carbohydrate degradation and lead to inhibit the plant growth attributes. These inhibitory effects were more pronounced in ZD 622. Collectively, low-dose MgO NPs reinforced the Mg contents, protected the plant growth, photosynthesis, total soluble carbohydrates, enzyme activities, and minimized the oxidative stress. While, the excessive MgO NP levels impaired the above-reported traits. Overall, ZD 622 was highly susceptible to MgO NP toxicity and ZD 635 was found most tolerant to MgO NP toxicity.

Biosynthesis of MgO Nanoparticles and Their Impact on the Properties of the PVA/Gelatin Nanocomposites for Smart Food Packaging Applications

Fabricating active and intelligent packaging materials has become the highest demand for catering to market needs, especially after the COVID-19 pandemic, for ensuring food safety. Thus, the wider objective of this article was to promote active and smart packaging biofilms possessing antibacterial and humidity-sensing properties for sustainable poly(vinyl alcohol) (PVA)/gelatin (Ge) reinforced with biosynthesized magnesium nanoparticles (MgO NPs) by a solvent-casting route. The UV-visible spectrum has been utilized to determine the optimized biosynthesized MgO NPs and then the nanostructure of optimized MgO NPs investigated by varying techniques such as XRD, SEM-EDX, TEM, FT-IR, and thermogravimetric analysis. Four MgO NPs proportions (i.e., 1, 3, 5, and 10 wt %) were used to fabricate PVA/Ge biofilms. In the biofilms system, the tensile results showcased that the nanocomposite film containing 5 wt % of MgO NPs had the highest tensile strength value (i.e., 22.10 MPs) compared to the other biofilms or the unfilled blank (i.e., 6.30 MPs). Correspondingly, the humidity-sensing data revealed that the PVA/Ge-1% MgO NPs sensor had higher sensitivity over a broad range of relative humidity from (7-97% RH) and at 100 Hz. Additionally, the hydrophobicity of biofilms, measured by water contact angle, UV-stability, and antioxidant and antibacterial properties was also analyzed to possibly use these biofilms in active food packaging with extended shelf life of foodstuffs. However, the PVA/Ge-1% MgO NPs biofilm was predominately found to possess attractive sensing properties and could be considered as a sensor for intelligent food packaging.

In Vitro Culture Studies for the Mitigation of Heavy Metal Stress in Plants

Heavy metals are among the most common and dangerous contaminants; their action on plants, as well as the possibility for plants to effectively absorb and translocate them, have been studied for several years, mainly for exploitation in phytoremediation, an environmentally friendly and potentially effective technology proposed and studied for the recovery of contaminated soils and waters. In this work, the analysis has focused on the studies developed using in vitro techniques on the possibilities of mitigating, in plants, the stress due to the presence of heavy metals and/or improving their absorption. These objectives can be pursued with the use of different substances and organisms, which have been examined in detail. The following are therefore presented in this review: an analysis of the role of metals and metalloids; the use of several plant growth regulators, with their mechanisms of action in different physiological phases of the plant; the activity of bacteria and fungi; and the role of other effective compounds, such as ascorbic acid and glutathione.

Evaluation of Nanomagnesium Oxide in Combination with Garlic Extract as an Endodontic Irrigant: An In Vitro Study

AIM

The aim of this in vitro study was to evaluate the effectiveness of the combination of garlic extract in combination with magnesium oxide (MgO) for use as an endodontic irrigant at various contact times.

MATERIALS AND METHODS

All 48 teeth were divided into 6 groups according to irrigation used after inoculation with Enterococcus faecalis and incubation. The control groups consisted of saline and sodium hypochlorite (NaOCl) used as irrigants and the test groups employed garlic extract combined with nano-magnesium oxide (nano-MgO) used as irrigant with two contact times, namely, 2 and 5 minutes, and garlic extract and nano-MgO used solely for 5 minutes each. Colony-forming units (CFUs) were counted after plating and incubation.

RESULTS

In NaOCl, and in both combination groups, there was a significant reduction in CFU counts. The saline group showed no decrease. Statistical analysis showed no difference in efficacy between NaOCl and the two combination groups. There was a statistical difference between the combination group and garlic/nano-MgO alone at both 2 and 5 minutes.

CONCLUSIONS

Under the conditions of this study, a novel irrigant, a combination of nanoparticles of MgO and garlic extract was as effective as NaOCl against E. faecalis in an in vitro model at two tested contact times.

CLINICAL SIGNIFICANCE

Combination of MgO nanoparticles and garlic extract achieves disinfection comparable to gold standard NaOCl without harmful caustic effects of hypochlorite.

Nanoparticle Synthesis and Their Integration into Polymer-Based Fibers for Biomedical Applications

The potential of nanoparticles as effective drug delivery systems combined with the versatility of fibers has led to the development of new and improved strategies to help in the diagnosis and treatment of diseases. Nanoparticles have extraordinary characteristics that are helpful in several applications, including wound dressings, microbial balance approaches, tissue regeneration, and cancer treatment. Owing to their large surface area, tailor-ability, and persistent diameter, fibers are also used for wound dressings, tissue engineering, controlled drug delivery, and protective clothing. The combination of nanoparticles with fibers has the power to generate delivery systems that have enhanced performance over the individual architectures. This review aims at illustrating the main possibilities and trends of fibers functionalized with nanoparticles, focusing on inorganic and organic nanoparticles and polymer-based fibers. Emphasis on the recent progress in the fabrication procedures of several types of nanoparticles and in the description of the most used polymers to produce fibers has been undertaken, along with the bioactivity of such alliances in several biomedical applications. To finish, future perspectives of nanoparticles incorporated within polymer-based fibers for clinical use are presented and discussed, thus showcasing relevant paths to follow for enhanced success in the field.

Moringa oleifera gum capped MgO nanoparticles: Synthesis, characterization, cyto- and ecotoxicity assessment

Nano-based drug delivery research is increasing due to the therapeutic applications for human health care. However, traditional chemical capping-based synthesis methods lead to unwanted toxicity effects. Hence, there is an urgent need for green synthesis-based and biocompatible synthesis methods. The current work describes for the first time the green synthesis of Moringa gum-capped MgO nanoparticles (Mgm-MgO NPs). Their antioxidant activity, hemolysis potential, cytotoxicity, phytotoxicity, toxicity by chorioallantoic membrane (CAM) chick embryo assay and in vivo toxicity in zebrafish embryos were described. The Mgm-MgO NPs exhibited significant antioxidant activity. The Mgm-MgO NPs at 500 μg/ml produced significant hemolysis (72.54 %), while lower concentrations did not. Besides, the cytotoxicity assessment of the Mgm-MgO NPs was conducted in PA-1 cells from human ovarian teratocarcinoma by MTT assay. The Mgm-MgO NPs (0.1-500 μg/ml) considerably reduced the viability of PA-1 cells. Furthermore, Mgm-MgO NPs had no significant effect on seed germination but had a significant effect on root and shoot length of mungbean (Vigna radiata). Additionally, the CAM assay was used to analyze the antiangiogenic potential of Mgm-MgO NPs, exhibiting no significant alterations after 72 h. Finally, the zebrafish embryotoxicity assay revealed that the Mgm-MgO NPs (0.1-500 μg/ml) did not affect morphology, mortality or survival rate.

Biopolymer Chitosan Surface Engineering with Magnesium Oxide-Pluronic-F127-Escin Nanoparticles on Human Breast Carcinoma Cell Line and Microbial Strains

Nanotechnology has been recognized as a highly interdisciplinary field of the twenty-first century, with diverse applications in biotechnology, healthcare, and material science. One of the most commonly employed non-toxic nanoparticles, magnesium oxide nanoparticles (MgO NPs), is simple, inexpensive, biocompatible, and biodegradable. Several researchers are interested in the biosynthesis process of MgO NPs through chemical and physical approaches. This is because of their simplicity, affordability, and environmental safety. In the current study, green MgO-Chitosan-Pluronic F127-Escin (MCsPFE) NPs have been synthesized and characterized via various techniques like UV-visible, Fourier-transform infrared spectroscopy, Energy dispersive X-ray composition analysis, Transmission electron microscopy, field emission scanning electron microscopy, X-ray Diffraction, Photoluminescence, and Dynamic light scattering analyses. The average crystallite size of MCsPFE NPs was 46 nm, and a face-centered cubic crystalline structure was observed. Further, the antimicrobial effectiveness of NPs against diverse pathogens has been assessed. The cytotoxic potential of the nanoparticles against MDA-MB-231 cell lines was evaluated using the MTT test, dual AO/EB, JC-1, DCFH-DA, and DAPI staining procedures. High antimicrobial efficacy of MCsPFE NPs against Gram-positive and Gram-negative bacterial strains as well as Candida albicans was observed. The findings concluded that the NPs augmented the ROS levels in the cells and altered the Δψm, leading to the initiation of the intrinsic apoptotic cell death pathway. Thus, green MCsPFE NPs possess immense potential to be employed as an effective antimicrobial and anticancer treatment option.

Green Synthesis of Hydroxyapatite Nanoparticles Using Monoon longifolium Leaf Extract for Removal of Fluoride from Aqueous Solution

Hydroxyapatite (Ca10(PO4)6(OH)2) calcium phosphate is a robust and viable magnetic material for the treatment of polluted air, water, and soil. Because of its unique structure and appealing properties such as high adsorption capabilities, acid-base adaptability, ion-exchange capability, and thermal stability, hydroxyapatite (HAp) has a lot of potential in the field of environmental management. An aqueous extract of Monoon longifolium leaves was used for the preparation of hydroxyapatite nonparticles as the adsorbent for fluoride ion removal from aqueous solution in this work, resulting in bio-based hydroxyapatite nanoparticles. The prepared adsorbent was characterized by using instrumental techniques such as TGA/DTA, XRD, AAS, FT-IR, and UV-Vis spectroscopy as well as SEM. The batch adsorption approach was used to determine the optimum adsorption efficiency of HAp NPs under various experimental conditions. As a result, the best removal efficiency corresponds to 0.75 g HAp NPs, 15 mg/L, and pH 7 at 50 minutes (96%). The equilibrium adsorption data were better fitted into the Freundlich isotherms (R2 = 0.99), and the pseudo-second-order kinetic model was found to be suitable (R2 = 0.99) for the kinetic model. Fluoride ion adsorption on HAp NPs is spontaneous, endothermic, and possible at temperatures over 318 K, according to thermodynamic calculations. The results hint at a conclusion that the synthesized HAp NPs were an efficient adsorbent for the removal of fluoride ions and the overall process can be an economical choice for scaled-up water treatment processes.

Synthesis of nanosize zinc oxide through aqueous sol-gel route in polyol medium

BACKGROUND

This study is aimed to synthesize nanosize zinc oxide by acid catalyzed sol-gel process using zinc nitrate hexahydrate as precursor, aqueous isopropanol as solvent and glycerin for making polyol system. The polyol mediated procedure was employed in combination with calcination induced synthesis of nanoparticles of numerous sizes obtained with the variation in calcination temperature from 500 to 900 ℃. The crystal structure of the prepared samples was characterized by X-ray diffraction analysis (XRD). Infrared spectroscopy (IR) was used to identify the surface hydroxyl groups. Thermal stability was confirmed by differential scanning calorimetry-thermogravimetric analysis (DSC-TGA) whereas field emission scanning electron microscopy (FESEM) was used to study the surface morphology of nanoparticles.

RESULTS

Results revealed the formation of hexagonal wurtzite structure of irregular shaped nanoparticles having size ranging from 50-100 nm. However, the particles combined to form agglomerates of 200-400 nm with the rise in calcination temperature.

CONCLUSIONS

These results indicate that nanosize zinc oxide can be synthesized successfully by a simple process comprising of glycerin as a low-cost, non-toxic and eco-friendly polyol followed by calcination at ambient temperatures.

MgO Heterostructures: From Synthesis to Applications

The energy storage capacity of batteries and supercapacitors has seen rising demand and problems as large-scale energy storage systems and electric gadgets have become more widely adopted. With the development of nano-scale materials, the electrodes of these devices have changed dramatically. Heterostructure materials have gained increased interest as next-generation materials due to their unique interfaces, resilient structures and synergistic effects, providing the capacity to improve energy/power outputs and battery longevity. This review focuses on the role of MgO in heterostructured magnetic and energy storage devices and their applications and synthetic strategies. The role of metal oxides in manufacturing heterostructures has received much attention, especially MgO. Heterostructures have stronger interactions between tightly packed interfaces and perform better than single structures. Due to their typical physical and chemical properties, MgO heterostructures have made a breakthrough in energy storage. In perpendicularly magnetized heterostructures, the MgO's thickness significantly affects the magnetic properties, which is good news for the next generation of high-speed magnetic storage devices.

Methods for Green Synthesis of Metallic Nanoparticles Using Plant Extracts and their Biological Applications - A Review

Nanotechnology, a fast-developing branch of science, is gaining extensive popularity among researchers simply because of the multitude of applications it can offer. In recent years, biological synthesis has been widely used instead of physical and chemical synthesis methods, which often produce toxic products. These synthesis methods are now being commonly adapted to discover new applications of nanoparticles synthesized using plant extracts. In this review, we elucidate the various ways by which nanoparticles can be biologically synthesized. We further discuss the applications of these nanoparticles.

Synthesis, Properties, and Selected Technical Applications of Magnesium Oxide Nanoparticles: A Review

In the last few decades, there has been a trend involving the use of nanoscale fillers in a variety of applications. Significant improvements have been achieved in the areas of their preparation and further applications (e.g., in industry, agriculture, and medicine). One of these promising materials is magnesium oxide (MgO), the unique properties of which make it a suitable candidate for use in a wide range of applications. Generally, MgO is a white, hygroscopic solid mineral, and its lattice consists of Mg2+ ions and O2− ions. Nanostructured MgO can be prepared through different chemical (bottom-up approach) or physical (top-down approach) routes. The required resultant properties (e.g., bandgap, crystallite size, and shape) can be achieved depending on the reaction conditions, basic starting materials, or their concentrations. In addition to its unique material properties, MgO is also potentially of interest due to its nontoxicity and environmental friendliness, which allow it to be widely used in medicine and biotechnological applications.

Green magnesium oxide nanoparticles-based modulation of cellular oxidative repair mechanisms to reduce arsenic uptake and translocation in rice (Oryza sativa L.) plants

Arsenic (As) accumulation catastrophically disturbs the stability of agricultural systems and human health. Rice easily accumulates a high amount of As from agriculture fields as compare with other cereal crops. Hence, innovative soil remediation methods are needed to deal with the detrimental effects of As on human health causing food security challenges. Here, we report the green synthesis and characterization of magnesium oxide nanoparticles (MgO-NPs) from a native Enterobacter sp. strain RTN2, which was genetically identified through 16S rRNA gene sequence analysis. The biosynthesis of MgO-NPs in reaction mixture was confirmed by UV-vis spectral analysis. X-ray diffraction (XRD) and fourier transform-infrared spectroscopy (FTIR) analysis showed the crystalline nature and surface properties of MgO-NPs, respectively. Moreover, electron microscopy (SEM-EDS, and TEM) imaging confirmed the synthesis of spherical shape of MgO-NPs with variable NPs sizes ranging from 38 to 57 nm. The results revealed that application of MgO-NPs (200 mg kg^-1) in As contaminated soil significantly increased the plant biomass, antioxidant enzymatic contents, and decreased reactive oxygen species and acropetal As translocation as compared with control treatment. The study concluded that biogenic MgO-NPs could be used to formulate a potent nanofertilizer for sustainable rice production in metal contaminated soils.

Moringa oleifera Leaf Extract-Mediated Green Synthesis of Nanostructured Alkaline Earth Oxide (MgO) and Its Physicochemical Properties

The magnesium oxide nanoparticles (MgO NPs) were prepared from Moringa oleifera leaf extract. Phytochemicals are derived from plant extract which are served as stabilizing and capping agents. This green route has been attracted owing to speed, reliable, and eco-friendly and cost-effective one. The synthesized magnesium oxide nanoparticles were taken into three different calcination temperatures (500, 600, and 700°C). The powder X-ray diffraction (PXRD) study shows a pure phase of face-centered cubic structure. Periclase MgO nanoparticles were prepared. The optical band gap of MgO nanoparticles is 4.5 eV, and its absorption in the UV region was observed by UV-visible spectroscopy (UV-Vis). Photoluminescence spectra have exhibited multicolor emissions were being at UV and visible region due to defect centers (F centers) of MgO nanoparticles. EDX (energy dispersive X-ray spectrum) has given the stoichiometric ratio of Mg and O. The functional groups have been studied by Fourier transformed infrared spectroscopy (FTIR), surface morphology transformation has been identified by scanning electron microscopy (SEM) studies, and VSM measurements have given the information of diamagnetic nature of MgO nanoparticles. H-R TEM micrographs have confirmed that particles were in nanorange matched with XRD report. Polycrystalline nature has been observed pattern information. TG-DSC characterization revealed phase transition and weight loss information. D-band and G-band of MgO nanoparticles are studied by micro-Raman analysis. Dielectric analysis has proven that MgO nanoparticles will be a promising candidate for linear dielectric ceramics, thermistor. The present resent studies have revealed that MgO powder will be an economical and promising candidate in superconductor, optoelectronic device, and energy storage applications.

Nanoparticles as therapeutic options for treating multidrug-resistant bacteria: research progress, challenges, and prospects

Resistance to antimicrobial agents has been alarming in recent years and poses a huge public health threat globally according to the WHO. The increase in morbidity and mortality resulting from microbial infections has been attributed to the emergence of multidrug-resistant microbes. Associated with the increase in multidrug resistance is the lack of new and effective antimicrobials. This has led to global initiatives to identify novel and more effective antimicrobial agents in addition to discovering novel and effective drug delivery and targeting methods. The use of nanoparticles as novel biomaterials to fully achieve this feat is currently gaining global attention. Nanoparticles could become an indispensable viable therapeutic option for treating drug-resistant infections. Of all the nanoparticles, the metals and metal oxide nanoparticles appear to offer the most promise and have attracted tremendous interest from many researchers. Moreover, the use of nanomaterials in photothermal therapy has received considerable attention over the years. This review provides current insight on antimicrobial resistance as well as the mechanisms of nanoparticle antibacterial activity. It offers an in-depth review of all the recent findings in the use of nanomaterials as agents against multi-resistant pathogenic bacteria. Also, nanomaterials that can respond to light stimuli (photothermal therapy) to kill microbes and facilitate enhanced drug delivery and release are discussed. Moreover, the synergistic interactions of nanoparticles with antibiotics and other nanomaterials, microbial adaptation strategies to nanoparticles, current challenges, and future prospects were extensively discussed.

Inorganic Nanoparticles and Composite Films for Antimicrobial Therapies

The development of drug-resistant microorganisms has become a critical issue for modern medicine and drug discovery and development with severe socio-economic and ecological implications. Since standard and conventional treatment options are generally inefficient, leading to infection persistence and spreading, novel strategies are fundamentally necessary in order to avoid serious global health problems. In this regard, both metal and metal oxide nanoparticles (NPs) demonstrated increased effectiveness as nanobiocides due to intrinsic antimicrobial properties and as nanocarriers for antimicrobial drugs. Among them, gold, silver, copper, zinc oxide, titanium oxide, magnesium oxide, and iron oxide NPs are the most preferred, owing to their proven antimicrobial mechanisms and bio/cytocompatibility. Furthermore, inorganic NPs can be incorporated or attached to organic/inorganic films, thus broadening their application within implant or catheter coatings and wound dressings. In this context, this paper aims to provide an up-to-date overview of the most recent studies investigating inorganic NPs and their integration into composite films designed for antimicrobial therapies.

Pickering emulsions stabilized by some inorganic materials

The paper presents studies of various solid stabilizers of emulsions based on inorganic materials. Inorganic colloidal particles have an advantage for obtaining of stable emulsions due to their safety for use in food, cosmetics, pharmaceutical industry and medicine. Pickering emulsions have a higher biodegradability compared to classical emulsions stabilized with surfactants. An overview of inorganic substances such as silicon dioxide, clay materials, metal and metal oxide nanoparticles, calcium compounds and carbon particles used for stabilizing of Pickering emulsions is considered. A variety of solid inorganic particles as well as modification of their surfaces by surfactants allows to obtain the stable Pickering emulsions of different types for a wide range of applications. It should be noted that despite a large number of studies, this class of disperse systems is still not studied fully; various methods of their preparation and influence of solid particle size on stability and size of emulsions droplets are shown.

A review on biosynthesis of metal nanoparticles and its environmental applications

Nanotechnology has become one of the emerging multi-disciplinary fields receiving universal attention and playing a substantial role in agriculture, environment and pharmacology. In spite of various techniques employed for nanoparticle synthesis such as laser ablation, mechanical milling, spinning and chemical deposition, usage of hazardous chemicals and expensiveness of the process makes it unsuitable for the continuous production. Hence the necessity of sustainable, economic and environment friendly approach development have increased in recent years. Microbial synthesis of nanoparticles connecting microbiology and nanotechnology is one of the green techniques employed for sustainable production. Gold, silver and other metal nanoparticles like platinum, palladium, molybdenum nanoparticles biosynthesis by bacteria, fungi, yeast and algae have been reported in the present review. On account of microbial rich community, several microbes have been explored for the production of nanoparticles. Nanoparticles are also employed for environmental remediation processes such as pollutant removal and detection of contaminants. Lack of monodispersity and prolonged duration of synthesis are the limitations of bio-synthesis process which can be overcome by optimization of methods of microbial cultivation and its extraction techniques. The current review describes the different microbes involved in the synthesis of nanoparticles and its environmental applications.

Phytoassisted synthesis of magnesium oxide nanoparticles from Pterocarpus marsupium rox.b heartwood extract and its biomedical applications

BACKGROUND

Unlike chemical techniques, the combination of metal oxide nanoparticles utilizing plant concentrate is a promising choice. The purpose of this work was to synthesize magnesium oxide nanoparticles (MgO-NPs) utilizing heartwood aqueous extract of Pterocarpus marsupium. The heartwood extract of Pterocarpus marsupium is rich in polyphenolic compounds and flavonoids that can be used as a green source for large-scale, simple, and eco-friendly production of MgO-NPs. The phytoassisted synthesis of MgO is characterized by UV-Visible spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) with EDS (energy dispersive X-ray spectroscopy), and transmission electron microscopy (TEM).

RESULTS

The formation of MgO-NPs is confirmed by a visual color change from colorless to dark brown and they displayed a wavelength of 310 nm in UV-Spectrophotometry analysis. The crystalline nature of the obtained biosynthesized nanoparticles are revealed by X-ray diffraction analysis. SEM results revealed the synthesized magnesium oxide nanoparticles formed by this cost-effective method are spherically shaped with an average size of < 20 nm. The presence of magnesium and oxygen were confirmed by the EDS data. TEM analysis proved the spherical shape of the nanoparticles with average particle size of 13.28 nm and SAED analysis confirms the crystalline nature of MgO-NPs. FT-IR investigation confirms the existence of the active compounds required to stabilize the magnesium oxide nanoparticles with hydroxyl and carboxyl and phenolic groups that act as reducing, stabilizing, and capping agent. All the nanoparticles vary in particle sizes between 15 and 25 nm and obtained a polydispersity index value of 0.248. The zeta-potential was measured and found to be - 2.9 mV. Further, MgO-NPs were tested for antibacterial action against Staphylococcus aureus (Gram-positive bacteria) and Escherichia coli (Gram-negative bacteria) by minimum inhibitory concentration technique were found to be potent against both the bacteria. The blended nanoparticles showed good antioxidant activity examined by the DPPH radical scavenging method, showed good anti-diabetic activity determined by alpha-amylase inhibitory activity, and displayed strong anti-inflammatory activity evaluated by the albumin denaturation method.

CONCLUSIONS

The investigation reports the eco-friendly, cost-effective method for synthesizing magnesium oxide nanoparticles from Pterocarpus marsupium Rox.b heartwood extract with biomedical applications.

The Bio-Synthesis of Three Metal Oxide Nanoparticles (ZnO, MnO2, and MgO) and Their Antibacterial Activity Against the Bacterial Leaf Blight Pathogen

Xanthomonas oryzae pv. oryzae (Xoo) is the most infectious pathogen of rice, which causes bacterial leaf blight (BLB) disease. However, the accumulation of chemical or antibiotic resistance of Xoo necessitate the development of its alternative control. In this study, we biologically synthesize three metal oxide nanoparticles (ZnO, MnO2, and MgO) using rhizophytic bacteria Paenibacillus polymyxa strain Sx3 as reducing agent. The biosynthesis of nanoparticles was confirmed and characterized by using UV-vis spectroscopy, XRD, FTIR, EDS, SEM, and TEM analysis. The UV Vis reflectance of the nanoparticle had peaks at 385, 230, and 230 nm with an average crystallite particle size 62.8, 18.8, and 10.9 nm for ZnO, MnO2, and MgO, respectively. Biogenic ZnO, MnO2, and MgO nanoparticles showed substantial significant inhibition effects against Xoo strain GZ 0006 at a concentration of 16.0 μg/ml, for which the antagonized area was 17, 13, and 13 mm and the biofilm formation was decreased by 74.5, 74.4, and 80.2%, respectively. Moreover, the underlining mechanism of nanoparticles was inferred to be in relation to the reactive oxygen species based on their antibacterial efficiency and the deformity in the cell wall phenomenon. Overall, an attractive and eco-friendly biogenic ZnO, MnO2, and MgO nanoparticles were successfully produced. Altogether, the results suggest that the nanoparticles had an excellent antibacterial efficacy against BLB disease in rice plants, together with the increase in growth parameter and rice biomass. In conclusion, the synthesized nanoparticles could serve as an alternative safe measure in combatting the antibiotic-resistant of Xoo.

Structural and physicochemical properties of Rheum emodi mediated Mg(OH)2 nanoparticles and their antibacterial and cytotoxic potential

In the present investigation, Rheum emodi roots extract mediated magnesium hydroxide nanoparticles [Mg(OH)2 NPs] through the bio-inspired experimental technique were synthesised. Mg(OH)2 NPs were characterised by using various characterisation techniques such as field emission scanning electron microscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet-visible spectroscopy. The formation of Mg(OH)2 NPs was confirmed by X-ray diffraction. The structural analysis confirmed the hexagonal crystal symmetry of Mg(OH)2 NPs with space group P-3m1 and space group no. 164 using the Rietveld refinement technique. TEM micrographs illustrated the nano-size formation of Mg(OH)2 NPs of spherical shape and size ∼14.86 nm. With the aid of FTIR data, plant metabolites such as anthraquinones have been identified as a stabilising and reducing agent for the synthesis of biogenic Mg(OH)2 NPs. The synthesised Mg(OH)2 NPs showed antimicrobial and cytotoxic potential against Gram-negative and Gram-positive bacteria such as Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) and MDA-MB-231 human breast cancer cell lines.

Bioengineered chitosan-magnesium nanocomposite: A novel agricultural antimicrobial agent against Acidovorax oryzae and Rhizoctonia solani for sustainable rice production

Chitosan is a potent biopolymer having promising antimicrobial properties against phytopathogens. Recently, engineered nanomaterials (ENMs) have gained much attention due to their potential application in the plant disease management. In this study, we reported the green synthesis of chitosan-magnesium (CS-Mg) nanocomposite and its antimicrobial activity against two rice pathogens namely Acidovorax oryzae and Rhizoctonia solani for the first time. The green MgO nanoparticles synthesized by using a native Bacillus sp. strain RNT3, were used to fabricate CS-Mg nanocomposite utilizing one-pot synthesis method. The synthesis of CS-Mg nanocomposite was further confirmed by using UV-vis spectroscopy, whereas, FTIR and XRD analysis showed the capping of CS-Mg nanocomposites by different functional groups together with their crystalline structure, respectively. Besides, SEM and TEM images revealed the spherical shape along with the particles size ranging from 29 to 60 nm. Moreover, EDS analysis confirmed the elemental purity of nanocomposite. The CS-Mg nanocomposite showed remarkable antimicrobial activity against A. oryzae and R. solani and significantly inhibited the growth as compared to non-treated control. The ultrastructure studies showed damaged structure of cell wall and internal cellular organelles after treatment with 100 μg mL^-1 CS-Mg nanocomposite. The results of this study indicated that CS-Mg nanocomposite-based antimicrobial agents could be considered as promising nanopesticides against phytopathogens in plant disease management.

Biogenic green synthesis of MgO nanoparticles using Saussurea costus biomasses for a comprehensive detection of their antimicrobial, cytotoxicity against MCF-7 breast cancer cells and photocatalysis potentials

Distinct morphological MgO nanoparticles (MgONPs) were synthesized using biomasses of Saussurea costus roots. The biomass of two varieties of Saussurea costus (Qustal hindi and Qustal bahri) were used in the green synthesis of MgONPs. The physical and chemical features of nanoparticles were confirmed by spectroscopic and microscopic techniques. The surface morphology of the obtained nanoparticles was detected at different magnifications by SEM and TEM microscopy and the size of nanoparticles were found to be 30 and 34 nm for Qustal hindi and Qustal bahri, respectively. The antimicrobial activity of the prepared MgONPs was screened against six pathogenic strains. The synthesized nanoparticles by Qustal bahri biomass exerted significant inhibition zones 15, 16, 18, 17, 14, and 10 mm against E. coli, P. aeruginosa, C. tropicalis and C. glabrata, S. aureus and B. subtilis as compared to those from Qustal hindi 12, 8 and 17 mm against B. subtilis, E. coli and C. tropicalis, respectively. MgONPs showed a potential cytotoxicity effect against MCF-7 breast cancer cell lines. Cellular investigations of MgONPs revealed that the prepared nanoparticles by Qustal bahri exhibited high cytotoxicity against MCF-7 cancer cell lines. IC50 values in MCF-7 cells were found to be 67.3% and 52.1% for MgONPs of Saussurea costus biomasses, respectively. Also, the photocatalytic activity of MgONPs of each Saussurea costus variety was comparatively studied. They exhibited an enhanced photocatalytic degradation of methylene blue after UV irradiation for 1 h as 92% and 59% for those prepared by Qustal bahri and Qustal hindi, respectively. Outcome of results revealed that the biosynthesized MgONPs showed promising biomedical potentials.

pH-Sensing Strips Based on Biologically Synthesized Ly-MgO Nanoparticles

MgO nanoparticles (NPs) are widely used in diverse areas ranging from catalysis to sensing. Besides this, there is a lack of information regarding their toxicity on fauna and flora. The venture of this work is to evaluate the toxicity behavior and pH-sensing performance of l-lysine-modified MgO (Ly-MgO) NPs synthesized by the green approach using the clove (Syzygium aromaticum) bud extract. The detailed investigations revealed that concentration plays an important role toward in vitro toxicity of Ly-MgO NPs. The Ly-MgO NPs showed 105% biocompatibility toward Vigna radiata (green gram) seeds at 100 ppm concentration. Zero inhibition on microbial growth was observed toward two bacterial strains. Further, pH-sensing strips based on these Ly-MgO nanostructures were developed to test pH-sensing performance at pH values ranging from 2.0 to 13.0. The repeatability as well as recyclability of the prepared pH strips was also analyzed. Nanobased pH paper strips based on Ly-MgO NPs provide a simple, reliable, nontoxic, and affordable method for pH measurements.

Biosynthesis and characterization of magnesium oxide and manganese dioxide nanoparticles using Matricaria chamomilla L. extract and its inhibitory effect on Acidovorax oryzae strain RS-2

Bacterial brown stripe (BBS) is one of the most economically important diseases of rice caused by Acidovorax oryzae (Ao). In order to ensure food security and safe consumption, the use of non-chemical approach is necessary. In this study, MgO and MnO₂ were synthesized using chamomile flower extract. The synthesized MgO and MnO₂ nanoparticles were characterized by UV-Visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, transmission/scanning electron microscopy. The sizes were 18.2 and 16.5 nm for MgO and MnO₂ nanoparticles, respectively. The MgO and MnO₂ nanoparticles reduced the growth of Ao strain RS-2 by 62.9 and 71.3%, respectively. Also, the biofilm formation and swimming motility were significantly reduced compared to the control. The antibacterial mechanisms of MgO and MnO₂ nanoparticles against RS-2 reveals that MgO and MnO₂ nanoparticles penetrated the cells and destroyed the cell membrane leading to leakage of cytoplasmic content. Also, the flow cytometry observation reveals that the apoptotic cell ratio of RS-2 increased from 0.97% to 99.52 and 99.94% when treated with MgO and MnO₂ nanoparticles, respectively. Altogether, the results suggest that the synthesized MgO and MnO₂ nanoparticles could serve as an alternative approach method for the management of BBS.

Magnesium oxide nanoparticles and thidiazuron enhance lead phytoaccumulation and antioxidative response in Raphanus sativus L

An in vitro study was conducted to evaluate the effects of thidiazuron (TDZ) growth regulator and magnesium oxide (MgO) nanoparticles on radish (Raphanus sativus L.) under lead (Pb) stress. Effects of TDZ and MgO on seed germination, growth, biomass, total phenolics and flavonoids, antioxidant potential, and Pb phytoaccumulation in different plant parts were assessed. Nanoparticles of MgO were synthesized with leaf extract of Sageretia thea (Osbeck) plant. Thidiazuron and MgO nanoparticles were added to growth media in individual and in combinations. Lead (50 mg L^-1) was added to growth media. Thidiazuron and MgO nanoparticles increased plant growth, phenolic and flavonoid contents, free radical scavenging activity, and lead phytoaccumulation. The increase was highly significant in TDZ and MgO nanoparticle combination treatments (T5, T6). Treatment (T6) showed a sixfold increase in Pb accumulation (1721.73 ± 17.4 μg g^-1 dry biomass) as compared to control (274.29 ± 4.23 μg^-1g^-1). Total phenolic and dry biomass showed significantly positive correlation in leaves (R² = 0.73), stem (R² = 0.58), and roots (R² = 0.72). The correlation of Pb accumulation and phenolic contents was significantly positive in root (R² = 0.80), stem (R² = 0.92), and leaves (R² = 0.69). Flavonoid showed a positive correlation with dry biomass and Pb accumulation. Antioxidant activity was highly increased in leaves followed by stem and root. Findings show that TDZ in combination with MgO nanoparticles can play a significant role in secondary metabolite production and Pb phytoaccumulation.

Anticancer, antimicrobial and photocatalytic activities of green synthesized magnesium oxide nanoparticles (MgONPs) using aqueous extract of Sargassum wightii

A rapid and ecofriendly fabrication of metal oxide nanoparticles using biogenic sources is the current trend being used to replace the toxic chemical method. The present study was carried out to synthesize magnesium oxide nanoparticles (MgONPs) using the marine brown algae Sargassum wighitii as the reducing and capping agent. The as-prepared MgONPs were characterized by spectroscopic and microscopic analyses. UV-visible spectrum of the MgONPs showed a sharp absorption peak at 322 nm. X- ray diffraction analysis illustrated that the MgONPs were crystalline in nature with a face-centered cubic structure. Presence of magnesium and oxygen were further confirmed by EDX profile. FTIR analysis showed the presence of functional groups specific for sulfated polysaccharides, which might be responsible for the synthesis of MgONPs. Zeta potential and dynamic light scattering analysis illustrated that the MgONPs were highly stable at 19.8 mV with an average size of 68.06 nm. MgONPs showed potent antibacterial activity and antifungal activities against human pathogens. Photocatalytic activity of MgONPs was witnessed by the quick degradation of the organic dye methylene blue on exposure to both sunlight and UV irradiation. MgONPs showed significant cytotoxicity against the lung cancer cell lines A549 in a dose dependent manner with the IC50 value of 37.5 ± 0.34 μg/ml. Safety evaluation using peripheral blood mononuclear cells (PBMCs) illustrated the MgONPs to be non-toxic in nature. Overall, the results concluded that the MgONPs generated using marine algae have exhibited scope for multifaceted biological applications.

Biosynthesis of Ultrasonically Modified Ag-MgO Nanocomposite and Its Potential for Antimicrobial Activity

This study reports a green synthesis route for a bilayered Ag-MgO nanocomposite using aqueous peel extract of Citrus paradisi (grapefruit red) under an accelerated uniform heating technique and its antibacterial potency against Escherichia coli. Surface modifications and composition of the nanocomposite were examined using a UV-visible spectrophotometer, transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) equipped with an energy dispersive X-ray (EDX) analyzer. The efficiencies of the as-synthesized Ag-MgO nanocomposite against Escherichia coli were examined. The synthesized Ag-MgO nanocomposite showed characteristic synergetic bands at 290 nm for MgO nanoparticle and at around 440 nm for Ag nanoparticle which blue-shifted to 380 nm in the composite. A spherically dispersed nanocomposite with cubical crystal lattice network with a diameter of about 20–100 nm comprising Ag nanoparticle embedded within MgO nanoparticles was obtained. The nanocomposite produced stronger antibacterial activity against Escherichia coli as compared to MgO nanoparticle, indicating a higher interaction between Ag and MgO ions. The nanocomposite was successfully synthesized via an efficient modified method by bioreductive agents with an improved synergistic antibacterial property towards water purification.