Biogenic synthesis of zinc oxide nanoparticles using Ruta graveolens (L.) and their antibacterial and antioxidant activities

Synergistic Antifungal Activity of Green Synthesized Zinc Oxide Nanoparticles and Fungicide Against Rhizoctonia solani Causing Rice Sheath Blight Disease

The biosynthesis of metal oxide nanoparticles using leaf extract of medicinal plants is a promising substitute for the traditional chemical method. This work aimed to synthesize zinc oxide nanoparticles using a green approach from local "Dholkolmi" (Ipomoea carnea) leaf extract which is a medicinal plant growing outside the roads of different regions of Bangladesh. The biosynthesized zinc oxide nanoparticles (ZnONPs) were characterized using ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, particle size analyzer, zeta-potential, scanning electron microscopy-energy dispersive spectroscopy, field emission scanning electron microscopy, and transmission electron microscopy. The results of UV-visible spectrophotometers observed an absorption peak at 373 nm wavelength, which confirmed the synthesis of ZnONPs in the solution. ZnONP sizes determined by XRD, DLS, and TEM are approximately ~37 nm, 105.61 nm, and 19.66 nm, respectively. ZnONPs were present because of the strong oxygen and zinc signals in the EDX profile. Additionally, this research assessed the antifungal activity of the biosynthesized ZnONPs and as well as folicur-incorporated ZnONPs against Rhizoctonia solani by the poison bait technique. According to the result of this study, ZnONPs synthesized from Ipomoea carnea leaf extract showed no promising result against Rhizoctonia solani mycelial growth reduction. But folicur-incorporated ZnONPs revealed a significant finding with a maximum 100% inhibition of mycelial growth at 1:1 and 3:1 ratio of ZnONPs with folicur fungicide under in vitro conditions. In the net house experiment, folicur-incorporated ZnONPs at a 1:1 ratio of ZnONPs with folicur showed considerable disease inhibition (26.96% RLH) as compared to disease control (52.83% RLH). In the case of rainfed transplanted Aus (March-June), the highest percentage of RLH was recorded in disease control (64.61%), and the lowest RLH was found in folicur (24.79%) followed by a 1:1 ratio of ZnONPs with folicur (32.10%) in field condition. On the other hand, the highest percentage of RLH was recorded in disease control (65.31%) and the lowest RLH was found in folicur (18.14%) followed by a 1:1 ratio of ZnONPs with folicur (21.39%) in rainfed transplanted Aman (July-November) season. The findings of the in vitro and in vivo studies provided evidence that ZnONPs and folicur had a strong synergistic antifungal impact and may be employed as a possible rice sheath blight disease management agent.

Phytosynthesis of zinc oxide nanoparticles for enhanced antioxidant, antibacterial, and photocatalytic properties: A greener approach to environmental sustainability

Multifunctional nanoparticles (NPs) production from phytochemicals is a sustainable process and an eco-friendly method, and this technique has a variety of uses. To accomplish this, we developed zinc oxide nanoparticles (ZnONPs) using the medicinal plant Tinospora cordifolia (TC). Instruments such as UV-Vis, XRD, FTIR, FE-SEM with EDX, and high-resolution TEM were applied to characterize the biosynthesized TC-ZnONPs. According to the UV-vis spectra, the synthesized TC-ZnONPs absorb at a wavelength centered at 374 nm, which corresponds to a 3.2 eV band gap. HRTEM was used to observe the morphology of the particle surface and the actual size of the nanostructures. TC-ZnONPs mostly exhibit the shapes of rectangles and triangles with a median size of 21 nm. The XRD data of the synthesized ZnONPs exhibited a number of peaks in the 2θ range, implying their crystalline nature. TC-ZnONPs proved remarkable free radical scavenging capacity on DPPH (2,2-Diphenyl-1-picrylhydrazyl), ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid), and NO (Nitric Oxide). TC-ZnONPs exhibited dynamic anti-bacterial activity through the formation of inhibition zones against Pseudomonas aeruginosa (18 ± 1.5 mm), Escherichia coli (18 ± 1.0 mm), Bacillus cereus (19 ± 0.5 mm), and Staphylococcus aureus (13 ± 1.1 mm). Additionally, when exposed to sunlight, TC-ZnONPs show excellent photocatalytic ability towards the degradation of methylene blue (MB) dye. These findings suggest that TC-ZnONPs are potential antioxidant, antibacterial, and photocatalytic agents.

A new polyazomethine-based pyrazole moiety and its reinforced nanocomposites @ ZnO for antimicrobial applications

A new class of biologically active polyazomethine/pyrazole and their related nanocomposites, polyazomethine/pyrazole/zinc oxide nanoparticles, have been successfully synthesized through the polycondensation technique in the form of polyazomethine pyrazole (PAZm/Py4-6) and polyazomethine/pyrazole/zinc oxide nanoparticles (PAZm/Py/ZnOa-c). The polymeric nanocomposites were prepared with a 5% loading of zinc oxide nanofiller using the same preparation technique, in addition to the help of ultrasonic radiation. The characteristics of the new polymers, such as solubility, viscometry, and molecular weight, were examined. All the polymers were completely soluble in the following solvents: concentrated sulfuric acid, formic acid, dimethylformamide, dimethyl sulfoxide, and tetrahydrofuran. Furthermore, the weight loss of the polyazomethine pyrazole (4, 5, and 6) at 800 °C was 67%, 95%, and 86%, respectively, which indicates the thermal stability of these polymers. At 800 °C, the polyazomethine/pyrazole/zinc oxide nanoparticles (a, b, and c) lost 74%, 68%, and 75% of their weight, respectively. This shows that adding zinc oxide nanoparticles made these compounds more stable at high temperatures. The X-Ray diffraction pattern of the polyazomethine pyrazole (PAZm/Py4-6) shows a number of sharp peaks with varying intensities. The polymers that were studied had straight crystal structures. Furthermore, the measurements of polyazomethine/pyrazole/zinc oxide nanoparticles (PAZm/Py/ZnOa-c) indicate a good merging of zinc oxide nanoparticles into the matrix of polymers. The antimicrobial activity of polymers and polymer nanocomposites was tested against some selected bacteria and fungi. The synthesized polymer (c) shows the highest activity against the two types of gram-negative bacteria selected. Most tested compounds were found to be effective against gram-positive bacteria except polyazomethine pyrazole (PAZm/Py5) and polyazomethine pyrazole (PAZm/Py6), which do not exhibit any activity. The synthesized polymers and their related nanocomposites were tested for their ability to kill the chosen fungi. All of them were effective against Aspergillus flavus, but only polyazomethine pyrazole (PAZm/Py4) and polyazomethine/pyrazole/zinc oxide (PAZm/Py/ZnOc) were effective against Candida albicans.

Comparative Effect of Chemical and Green Zinc Nanoparticles on the Growth, Hematology, Serum Biochemical, Antioxidant Parameters, and Immunity in Serum and Mucus of Goldfish, Carassius auratus (Linnaeus, 1758)

Recently, nano feed supplement research has great attention to improving healthy aquatic production and improving the aquatic environment. With the aims of the present study, chemical and green synthesized nanoparticles are characterized by various instrumentation analyses, namely UV-Vis spectrophotometry (UV-Vis), X-ray diffraction (XRD), Fourier transform infra-red (FTIR) spectroscopy, and scanning electron microscope (SEM). After characterization analysis of these nanoparticles utilized in aquatic animals, the composition ratio is as follows: controls (without ZnO-NPs (0 mg/L)), T1 (0.9 mg/L ZnO-NPs), T2 (1.9 mg/L ZnO-NPs), T3 (0.9 mg/L GZnO-NPs), T4 (1.9 mg/L GZnO-NPs). SEM investigation report demonstrates that the structure of the surface of green synthesized zinc oxide nanoparticles (GZnO-NPs) was conical shape and the size ranging was from 60 to 70 nm. Concerning hematological parameters, the quantity of hemoglobin increased in different doses of green zinc nanoparticles, but the values of MCV and MCH decreased somewhat. However, this decrease was the highest in the T2 group. Total protein and albumin decreased in T2 and triglyceride, cholesterol, glucose, cortisol, creatinine, and urea increased, while in T3 and T4 groups, changes in biochemical parameters were evaluated as positive. Mucosal and serum immunological parameters in the T2 group showed a significant decrease compared to other groups. In zinc nanoparticles, with increasing dose, oxidative damage is aggravated, so in the T2 group, a decrease in antioxidant enzymes and an increase in MDA were seen compared to other groups. In this regard, the concentration of liver enzymes AST and ALT increased in the T2 group compared with control and other groups. This can confirm liver damage in this dose compared with control and other groups. This research work suggests that green synthesized form of zinc nanoparticles in higher doses have less toxic effects in comparison to the chemical form of zinc nanoparticles and can act as suitable nutrient supplements in aquatic animals.

Green synthesis of zinc oxide nano particles using Allium cepa L. waste peel extracts and its antioxidant and antibacterial activities

Synthesis of nanoparticles through the green approach using plant and vegetable extracts has gained popularity since they are thought to be efficient and cost-effective materials. This study is designed to synthesize zinc oxide nanoparticles (ZnO-NPs) from onion waste peel extract (Allium cepa L.) via the green synthesis approach. The synthesized ZnO-NPs were characterized by utilizing the UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), Energy Dispersive X-ray (EDX), Field Emission Scanning Electron Microscopy (FE-SEM) and X-ray Powder Diffraction (XRD)techniques. The nanoparticles formation was confirmed by the UV-Vis sharp absorption spectra at 318 and 322 nm. The synthesized ZnO-NPs size and shape was revealed by the XRD and SEM respectively. Smallest nanoparticle average crystallite size was found 57.38 nm with hexagonal shape. The bioactive functional groups that are in charge of capping and stabilizing the ZnO-NPs was assured by the FTIR data. Further, prepared ZnO-NPs were used to assess their possible antioxidant and antibacterial properties. DPPH test for free radical scavenging showed potential antioxidant properties of the synthesized ZnO-NPs. The antibacterial activity were studied against three clinical strains: P. aeruginosa, E. coli, and S. aureus with the maximum zone of inhibition 13.17 mm, 22.00 mm and 12.35 mm respectively at 100 μg/mL subsequently minimum inhibitory concentration was found 50 μg/mL for P. aeruginosa, and S. aureus whereas 100 μg/mL for E. coli. Antioxidant and antibacterial activity tests appear bio-resource based ZnO-NPs from Allium cepa L. extract have effects on free radical and growth of microorganisms.Therefore, it could be a promising candidates for agricultural and food safety applications as an effective antimicrobial agent against pathogenic microorganisms and also can address future biomedical applications after complete in vivo study.

An Overview of Metallic Nanoparticles: Classification, Synthesis, Applications, and their Patents

BACKGROUND

Nanotechnology has gained enormous attention in pharmaceutical research. Nanotechnology is used in the development of nanoparticles with sizes ranging from 1-100 nm, with several extraordinary features. Metallic nanoparticles (MNPs) are used in various areas, such as molecular biology, biosensors, bio imaging, biomedical devices, diagnosis, pharmaceuticals, etc., for their specific applications.

METHODOLOGY

For this study, we have performed a systematic search and screening of the literature and identified the articles and patents focusing on various physical, chemical, and biological methods for the synthesis of metal nanoparticles and their pharmaceutical applications.

RESULTS

A total of 174 references have been included in this present review, of which 23 references for recent patents were included. Then, 29 papers were shortlisted to describe the advantages, disadvantages, and physical and chemical methods for their synthesis, and 28 articles were selected to provide the data for biological methods for the formulation of metal NPs from bacteria, algae, fungi, and plants with their extensive synthetic procedures. Moreover, 27 articles outlined various clinical applications of metal NPs due to their antimicrobial and anticancer activities and their use in drug delivery.

CONCLUSION

Several reviews are available on the synthesis of metal nanoparticles and their pharmaceutical applications. However, this review provides updated research data along with the various methods employed for their development. It also summarizes their various advantages and clinical applications (anticancer, antimicrobial drug delivery, and many others) for various phytoconstituents. The overview of earlier patents by several scientists in the arena of metallic nanoparticle preparation and formulation is also presented. This review will be helpful in increasing the current knowledge and will also inspire to innovation of nanoparticles for the precise and targeted delivery of phytoconstituents for the treatment of several diseases.

Biogenic synthesis of novel nanomaterials and their applications

Despite the many benefits derived from the unique features and practicality of nanoparticles, the release of their toxic by-products or products from the synthesis stage into the environment could negatively impact natural resources and organisms. The physical and chemical methods for nanoparticle synthesis involve high energy consumption and the use of hazardous chemicals, respectively, going against the principles of green chemistry. Biological methods of synthesis that rely on extracts from a broad range of natural plants, and microorganisms, such as fungi, bacteria, algae, and yeast, have emerged as viable alternatives to the physical and chemical methods. Nanoparticles synthesized through biogenic pathways are particularly useful for biological applications that have high concerns about contamination. Herein, we review the physical and chemical methods of nanoparticle synthesis and present a detailed overview of the biogenic methods used for the synthesis of different nanoparticles. The major points discussed in this study are the following: (1) the fundamentals of the physical and chemical methods of nanoparticle syntheses, (2) the use of different biological precursors (microorganisms and plant extracts) to synthesize gold, silver, selenium, iron, and other metal nanoparticles, and (3) the applications of biogenic nanoparticles in diverse fields of study, including the environment, health, material science, and analytical chemistry.

Plant-derived nanomaterials (PDNM): a review on pharmacological potentials against pathogenic microbes, antimicrobial resistance (AMR) and some metabolic diseases

Plant-derived nanomaterials (PDNM) have gained significant attention recently due to their potential pharmacological applications against pathogenic microbes, antimicrobial resistance (AMR), and certain metabolic diseases. This review introduces the concept of PDNMs and their unique properties, including their small size, high surface area, and ability to penetrate biological barriers. Besides various methods for synthesizing PDNMs, such as green synthesis techniques that utilize plant extracts and natural compounds, the advantages of using plant-derived materials, such as their biocompatibility, biodegradability, and low toxicity, were elucidated. In addition, it examines the recent and emerging trends in nanomaterials derived from plant approaches to combat antimicrobial resistance and metabolic diseases. The sizes of nanomaterials and their surface areas are vital as they play essential roles in the interactions and relationships between these materials and the biological components or organization. We critically analyze the biomedical applications of nanoparticles which include antibacterial composites for implantable devices and nanosystems to combat antimicrobial resistance, enhance antibiotic delivery, and improve microbial diagnostic/detection systemsIn addition, plant extracts can potentially interfere with metabolic syndrome pathways; hence most nano-formulations can reduce chronic inflammation, insulin resistance, oxidative stress, lipid profile, and antimicrobial resistance. As a result, these innovative plant-based nanosystems may be a promising contender for various pharmacological applications.

Recent development of metal oxides and chalcogenides as antimicrobial agents

Pathogenic microbes are a major concern in hospitals and other healthcare facilities because they affect the proper performance of medical devices, surgical devices, etc. Due to the antimicrobial resistance or multidrug resistance, combatting these microbial infections has grown to be a significant research area in science and medicine as well as a critical health concern. Antibiotic resistance is where microbes acquire and innately exhibit resistance to antimicrobial agents. Therefore, the development of materials with promising antimicrobial strategy is a necessity. Amongst other available antimicrobial agents, metal oxide and chalcogenide-based materials have shown to be promising antimicrobial agents due to their inherent antimicrobial activity as well as their ability to kill and inhibit the growth of microbes effectively. Moreover, other features including the superior efficacy, low toxicity, tunable structure, and band gap energy has makes metal oxides (i.e. TiO₂, ZnO, SnO₂ and CeO₂ in particular) and chalcogenides (Ag₂S, MoS₂, and CuS) promising candidates for antimicrobial applications as illustrated by examples discussed in this review.

Biogenic Zinc Oxide Nanoparticles and Their Biomedical Applications: A Review

Nanotechnology has inscribed novel perception into the material science and one of the most extensively used nanomaterials is Zinc oxide nanoparticles (ZnO NPs) with healthcare and biomedical applications. Because of its outstanding biocompatibility, low toxicity, and low cost, ZnO NPs have become one of the most prominent metal oxide NPs in biological applications. This review highlights the different aspects of ZnO NPs, like their green synthesis as a substitute of conventional route due to avoidance of threat of hazardous, costly precursors and subsequent mostly therapeutic applications. Due to their wide bandwidth and high excitation binding energy, ZnO NPs have undergone extensive research. In addition to their potential applications as antibiotics, antioxidants, anti-diabetics, and cytotoxic agents, ZnO NPs also hold a promising future as an antiviral treatment for SARS-CoV-2. Zn has antiviral properties and may be effective against a variety of respiratory virus species, particularly SARS-CoV-2. This review includes a variety of topics, including the virus's structural properties, an overview of infection mechanism, and current COVID-19 treatments. Nanotechnology-based techniques for the prevention, diagnosis, and treatment of COVID-19 are also discussed in this review.

Cytotoxic, Antidiabetic, and Antioxidant Study of Biogenically Improvised Elsholtzia blanda and Chitosan-Assisted Zinc Oxide Nanoparticles

In the present study, we have improvised a biogenic method to fabricate zinc oxide nanoparticles (ZnO NPs) using chitosan and an aqueous extract of the leaves of Elsholtzia blanda. Characterization of the fabricated products was carried out with the help of ultraviolet-visible, Fourier transform infrared, X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction, and energy-dispersive X-ray analyses. The size of the improvised ZnO NP measured between 20 and 70 nm and had a spherical and hexagonal shape. The ZnO NPs proved to be highly effective in the antidiabetic test as the sample showed the highest percentage of enzyme inhibition at 74% ± 3.7, while in the antioxidant test, 78% was the maximum percentage of 2,2-diphenyl-1-picrylhydrazyl hydrate scavenging activity. The cytotoxic effect was investigated against the human osteosarcoma (MG-63) cell line, and the IC₅₀ value was 62.61 μg/mL. Photocatalytic efficiency was studied by the degradation of Congo red where 91% of dye degradation was observed. From the various analyses, it can be concluded that the as-synthesized NPs may be suitable for various biomedical applications as well as for environmental remediation.

Recent Advances in the Investigation of Poly(lactic acid) (PLA) Nanocomposites: Incorporation of Various Nanofillers and their Properties and Applications

Poly(lactic acid) (PLA) is considered the most promising biobased substitute for fossil-derived polymers due to its compostability, biocompatibility, renewability, and good thermomechanical properties. However, PLA suffers from several shortcomings, such as low heat distortion temperature, thermal resistance, and rate of crystallization, whereas some other specific properties, i.e., flame retardancy, anti-UV, antibacterial or barrier properties, antistatic to conductive electrical characteristics, etc., are required by different end-use sectors. The addition of different nanofillers represents an attractive way to develop and enhance the properties of neat PLA. Numerous nanofillers with different architectures and properties have been investigated, with satisfactory achievements, in the design of PLA nanocomposites. This review paper overviews the current advances in the synthetic routes of PLA nanocomposites, the imparted properties of each nano-additive, as well as the numerous applications of PLA nanocomposites in various industrial fields.

Plant and Microbial Approaches as Green Methods for the Synthesis of Nanomaterials: Synthesis, Applications, and Future Perspectives

The unique biological and physicochemical characteristics of biogenic (green-synthesized) nanomaterials (NMs) have attracted significant interest in different fields, with applications in the agrochemical, food, medication delivery, cosmetics, cellular imaging, and biomedical industries. To synthesize biogenic nanomaterials, green synthesis techniques use microorganisms, plant extracts, or proteins as bio-capping and bio-reducing agents and their role as bio-nanofactories for material synthesis at the nanoscale size. Green chemistry is environmentally benign, biocompatible, nontoxic, and economically effective. By taking into account the findings from recent investigations, we shed light on the most recent developments in the green synthesis of nanomaterials using different types of microbes and plants. Additionally, we cover different applications of green-synthesized nanomaterials in the food and textile industries, water treatment, and biomedical applications. Furthermore, we discuss the future perspectives of the green synthesis of nanomaterials to advance their production and applications.

A Critical Review of the Antimicrobial and Antibiofilm Activities of Green-Synthesized Plant-Based Metallic Nanoparticles

Metallic nanoparticles (MNPs) produced by green synthesis using plant extracts have attracted huge interest in the scientific community due to their excellent antibacterial, antifungal and antibiofilm activities. To evaluate these pharmacological properties, several methods or protocols have been successfully developed and implemented. Although these protocols were mostly inspired by the guidelines from national and international regulatory bodies, they suffer from a glaring absence of standardization of the experimental conditions. This situation leads to a lack of reproducibility and comparability of data from different study settings. To minimize these problems, guidelines for the antimicrobial and antibiofilm evaluation of MNPs should be developed by specialists in the field. Being aware of the immensity of the workload and the efforts required to achieve this, we set out to undertake a meticulous literature review of different experimental protocols and laboratory conditions used for the antimicrobial and antibiofilm evaluation of MNPs that could be used as a basis for future guidelines. This review also brings together all the discrepancies resulting from the different experimental designs and emphasizes their impact on the biological activities as well as their interpretation. Finally, the paper proposes a general overview that requires extensive experimental investigations to set the stage for the future development of effective antimicrobial MNPs using green synthesis.

Facile Green Synthesis of Zinc Oxide Nanoparticles with Potential Synergistic Activity with Common Antifungal Agents against Multidrug-Resistant Candidal Strains

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 (100µg/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.

Exploring the Journey of Zinc Oxide Nanoparticles (ZnO-NPs) toward Biomedical Applications

The field of nanotechnology is concerned with the creation and application of materials having a nanoscale spatial dimensioning. Having a considerable surface area to volume ratio, nanoparticles have particularly unique properties. Several chemical and physical strategies have been used to prepare zinc oxide nanoparticles (ZnO-NPs). Still, biological methods using green or natural routes in various underlying substances (e.g., plant extracts, enzymes, and microorganisms) can be more environmentally friendly and cost-effective than chemical and/or physical methods in the long run. ZnO-NPs are now being studied as antibacterial agents in nanoscale and microscale formulations. The purpose of this study is to analyze the prevalent traditional method of generating ZnO-NPs, as well as its harmful side effects, and how it might be addressed utilizing an eco-friendly green approach. The study's primary focus is on the potential biomedical applications of green synthesized ZnO-NPs. Biocompatibility and biomedical qualities have been improved in green-synthesized ZnO-NPs over their traditionally produced counterparts, making them excellent antibacterial and cancer-fighting drugs. Additionally, these ZnO-NPs are beneficial when combined with the healing processes of wounds and biosensing components to trace small portions of biomarkers linked with various disorders. It has also been discovered that ZnO-NPs can distribute and sense drugs. Green-synthesized ZnO-NPs are compared to traditionally synthesized ones in this review, which shows that they have outstanding potential as a potent biological agent, as well as related hazardous properties.

Recent progress of phytogenic synthesis of ZnO, SnO2, and CeO2 nanomaterials

A critical investigation on the fabrication of metal oxide nanoparticles (NPs) such as ZnO, SnO₂, and CeO₂ NPs synthesized from green and phytogenic method using plants and various plant parts have been compiled. In this review, different plant extraction methods, synthesis methods, characterization techniques, effects of plant extract on the physical, chemical, and optical properties of green synthesized ZnO, SnO₂, and CeO₂ NPs also have been compiled and discussed. Effect of several parameters on the size, morphology, and optical band gap energy of metal oxide have been explored. Moreover, the role of solvents has been found important and discussed. Extract composition i.e. phytochemicals also found to affect the morphology and size of the synthesized ZnO, SnO₂, and CeO₂ NPs. It was found that, there is no universal extraction method that is ideal and extraction techniques is unique to the plant type, plant parts, and solvent used.

Green approaches in synthesising nanomaterials for environmental nanobioremediation: Technological advancements, applications, benefits and challenges

Green synthesis approaches of nanomaterials (NMs) have received considerable attention in recent years as it addresses the sustainability issues posed by conventional synthesis methods. However, recent works of literature do not present the complete picture of biogenic NMs. This paper addresses the previous gaps by providing insights into the stability and toxicity of NMs, critically reviewing the various biological agents and solvents required for synthesis, sheds light on the factors that affect biosynthesis, and outlines the applications of NMs across various sectors. Despite the advantages of green synthesis, current methods face challenges with safe and appropriate solvent selection, process parameters that affect the synthesis process, nanomaterial cytotoxicity, bulk production and NM morphology control, tedious maintenance, and knowledge deficiencies. Consequently, the green synthesis of NMs is largely trapped in the laboratory phase. Nevertheless, the environmental friendliness, biocompatibility, and sensitivities of the resulting NMs have wider applications in biomedical science, environmental remediation, and consumer industries. To the scale-up application of biogenic NMs, future research should be focused on understanding the mechanisms of the synthesis processes, identifying more biological and chemical agents that can be used in synthesis, and developing the practicality of green synthesis at the industrial scale, and optimizing the factors affecting the synthesis process.

Green Nanotechnology: Plant-Mediated Nanoparticle Synthesis and Application

The key pathways for synthesizing nanoparticles are physical and chemical, usually expensive and possibly hazardous to the environment. In the recent past, the evaluation of green chemistry or biological techniques for synthesizing metal nanoparticles from plant extracts has drawn the attention of many researchers. The literature on the green production of nanoparticles using various metals (i.e., gold, silver, zinc, titanium and palladium) and plant extracts is discussed in this study. The generalized mechanism of nanoparticle synthesis involves reduction, stabilization, nucleation, aggregation and capping, followed by characterization. During biosynthesis, major difficulties often faced in maintaining the structure, size and yield of particles can be solved by monitoring the development parameters such as temperature, pH and reaction period. To establish a widely accepted approach, researchers must first explore the actual process underlying the plant-assisted synthesis of a metal nanoparticle and its action on others. The green synthesis of NPs is gaining attention owing to its facilitation of the development of alternative, sustainable, safer, less toxic and environment-friendly approaches. Thus, green nanotechnology using plant extract opens up new possibilities for the synthesis of novel nanoparticles with the desirable characteristics required for developing biosensors, biomedicine, cosmetics and nano-biotechnology, and in electrochemical, catalytic, antibacterial, electronics, sensing and other applications.

Trichoderma harzianum-Mediated ZnO Nanoparticles: A Green Tool for Controlling Soil-Borne Pathogens in Cotton

ZnO-based nanomaterials have high antifungal effects, such as inhibition of growth and reproduction of some pathogenic fungi, such as Fusarium sp., Rhizoctonia solani and Macrophomina phaseolina. Therefore, we report the extracellular synthesis of ZnONPs using a potential fungal antagonist (Trichoderma harzianum). ZnONPs were then characterized for their size, shape, charge and composition by visual analysis, UV–visible spectrometry, X-ray diffraction (XRD), Zeta potential, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). The TEM test confirmed that the size of the produced ZnONPs was 8–23 nm. The green synthesized ZnONPs were characterized by Fourier transform infrared spectroscopy (FTIR) studies to reveal the functional group attributed to the formation of ZnONPs. For the first time, trichogenic ZnONPs were shown to have fungicidal action against three soil–cotton pathogenic fungi in the laboratory and greenhouse. An antifungal examination was used to evaluate the bioactivity of the mycogenic ZnONPs in addition to two chemical fungicides (Moncut and Maxim XL) against three soil-borne pathogens, including Fusarium sp., Rhizoctonia solani and Macrophomina phaseolina. The findings of this study show a novel fungicidal activity in in vitro assay for complete inhibition of fungal growth of tested plant pathogenic fungi, as well as a considerable reduction in cotton seedling disease symptoms under greenhouse conditions. The formulation of a trichogenic ZnONPs form was found to increase its antifungal effect significantly. Finally, the utilization of biocontrol agents, such as T. harzianum, could be a safe strategy for the synthesis of a medium-scale of ZnONPs and employ it for fungal disease control in cotton.

Nanotechnology as a Processing and Packaging Tool to Improve Meat Quality and Safety

Nanoparticles are gaining momentum as a smart tool towards a safer, more cost-effective and sustainable food chain. This study aimed to provide an overview of the potential uses, preparation, properties, and applications of nanoparticles to process and preserve fresh meat and processed meat products. Nanoparticles can be used to reinforce the packaging material resulting in the improvement of sensory, functional, and nutritional aspects of meat and processed meat products. Further, these particles can be used in smart packaging as biosensors to extend the shelf-life of fresh and processed meat products and also to monitor the final quality of these products during the storage period. Nanoparticles are included in product formulation as carriers of health-beneficial and/or functional ingredients. They showed great efficiency in encapsulating bioactive ingredients and preserving their properties to ensure their functionality (e.g., antioxidant and antimicrobial) in meat products. As a result, nanoparticles can efficiently contribute to ensuring product safety and quality whilst reducing wastage and costs. Nevertheless, a wider implementation of nanotechnology in meat industry is highly related to its economic value, consumers' acceptance, and the regulatory framework. Being a novel technology, concerns over the toxicity of nanoparticles are still controversial and therefore efficient analytical tools are deemed crucial for the identification and quantification of nanocomponents in meat products. Thus, migration studies about nanoparticles from the packaging into meat and meat products are still a concern as it has implications for human health associated with their toxicity. Moreover, focused economic evaluations for implementing nanoparticles in meat packaging are crucial since the current literature is still scarce and targeted studies are needed before further industrial applications.

Engineering the Multi-Enzymatic Activity of Cerium Oxide Nanoparticle Coatings for the Antioxidant Protection of Implants

Imbalance of oxidants is a universal contributor to the failure of implanted devices and tissues. A sustained oxidative environment leads to cytotoxicity, prolonged inflammation, and ultimately host rejection of implanted devices/grafts. The incorporation of antioxidant materials can inhibit this redox/inflammatory cycle and enhance implant efficacy. Cerium oxide nanoparticles (CONP) is a highly promising agent that exhibits potent, ubiquitous, and self-renewable antioxidant properties. Integrating CONP as surface coatings provides ease in translating antioxidant properties to various implants/grafts. Herein, we describe the formation of CONP coatings, generated via the sequential deposition of CONP and alginate, and the impact of coating properties, pH, and polymer molecular weight, on their resulting redox profile. Investigation of CONP deposition, layer formation, and coating uniformity/thickness on their resulting oxidant scavenging activity identified key parameters for customizing global antioxidant properties. Results found lower molecular weight alginates and physiological pH shift CONP activity to a higher H2O2 to O2 --scavenging capability. The antioxidant properties measured for these various coatings translated to distinct antioxidant protection to the underlying encapsulated cells. Information gained from this work can be leveraged to tailor coatings towards specific oxidant-scavenging applications and prolong the function of medical devices and cellular implants.

Precursor effects on the physical, biological, and catalytic properties of Fagonia indica Burm.f. mediated zinc oxide nanoparticles

We report a facile, green and precursor-based comparative study on the biosynthesis of zinc oxide (ZnO) nanoparticles (NPs) using anticancerous Fagonia indica as effective chelating agent. Biosynthesis was carried out using zinc sulfate and zinc acetate as precursor salts to make ZnO_S and ZnO_A NPs under similar experimental conditions which were characterized extensively for physical and biological properties. Scherrer equation deduced a mean crystallite size of ~23.4 nm for ZnO_A NPs and ~41 nm for ZnO_S NPs. The nature of the NPs was compared using UV, diffuse reflectance spectra, Fourier transform infrared spectroscopy, thermogravimetric analysis-DTA, selected area electron diffraction, EDS, zeta potential, high resolution (HR)-SEM, and HR-TEM. Detailed in vitro pharmacognostic activities revealed a significant therapeutic potential for ZnO_A and ZnO_S . Potential antimicrobial activities for the NPs and their nanocosmeceutical formulations are reported. ZnO_A NPs were more cytotoxic to Leishmania tropica as compared to ZnO_S . Significant antioxidant and protein kinase inhibition was obtained. The hemolytic assay indicated a hemocompatible nature of both ZnO_A and ZnO_S NPs. Catalytic degradation of crystal violet dye (CVD) by NPs was examined under different parameters (light, dark, UV). Furthermore, sonophotocatalytic degradation of CVD was also studied. Our results suggested that precursor can have a significant effect on the physical, biological, and catalytic properties of the NPs. In future, we recommend different other in vitro, in vivo biological activities, and mechanistic studies of these as-synthesized NPs.

Do Iron Oxide Nanoparticles Have Significant Antibacterial Properties?

The use of metal oxide nanoparticles is one of the promising ways for overcoming antibiotic resistance in bacteria. Iron oxide nanoparticles (IONPs) have found wide applications in different fields of biomedicine. Several studies have suggested using the antimicrobial potential of IONPs. Iron is one of the key microelements and plays an important role in the function of living systems of different hierarchies. Iron abundance and its physiological functions bring into question the ability of iron compounds at the same concentrations, on the one hand, to inhibit the microbial growth and, on the other hand, to positively affect mammalian cells. At present, multiple studies have been published that show the antimicrobial effect of IONPs against Gram-negative and Gram-positive bacteria and fungi. Several studies have established that IONPs have a low toxicity to eukaryotic cells. It gives hope that IONPs can be considered potential antimicrobial agents of the new generation that combine antimicrobial action and high biocompatibility with the human body. This review is intended to inform readers about the available data on the antimicrobial properties of IONPs, a range of susceptible bacteria, mechanisms of the antibacterial action, dependence of the antibacterial action of IONPs on the method for synthesis, and the biocompatibility of IONPs with eukaryotic cells and tissues.

Green Synthesis, Structural Characterization and Photocatalytic Applications of ZnO Nanoconjugates Using Heliotropium indicum

In recent years, biosynthesized zinc oxide nanoparticles (ZnO NPs) have been gaining importance due to their unique properties and tremendous applications. This study aimed to fabricate ZnO NPs by using extracts from various parts of the traditional medicinal plant Heliotropium indicum (H. indicum) and evaluate their photocatalytic activity. Further, their potential in photoluminescence and fluorescence resonance energy transfer (FRET) was assessed. The Ultraviolet-Visible spectrum exhibited a hypsochromic shifted absorption band between 350–380 nm. Transmission electron microscopy (TEM) analysis revealed spherical NPs, while X-ray diffraction (XRD) data revealed wurtzite, hexagonal and crystalline nature. The TEM and XRD consistently determined an average particle size range from 19 to 53 nm. The photocatalytic degradation reaches a maximum of 95% for biogenic ZnO NPs by monitoring spectrophotometrically the degradation of methylene blue dye (λmax = 662.8 nm) under solar irradiation. Photoluminescence analysis revealed differentiated spectra with high-intensity emission peaks for biogenic ZnO NPs compared with chemically synthesized ZnO NPs. Eventually, the highest efficiency of FRET (80%) was found in ZnO NPs synthesized from the leaves. This remains the first report highlighting the multifunctional ZnO NPs capabilities mediated by using H. indicum, which could lead to important potential environmental and biomedical applications.

Nanoparticles as Novel Emerging Therapeutic Antibacterial Agents in the Antibiotics Resistant Era

Microorganisms are highly resistant to the antibiotics that are commonly used and thus are becoming serious public health problem. There is an urgent need for new approaches to monitor microbial behavior, and hence, nanomaterial can be a very promising solution. Nanotechnology has led to generation of novel antimicrobial agents such as gold, silver, zinc, copper, poly-£-lysine, iron, and chitosan which have shown remarkable potential, demonstrating their applicability as proficient antibiotic agents against various pathogenic bacterial species. The antimicrobial nanoproduct physically kills the organism's cell membranes that prevent the production of drug-resistant microorganisms. These nanosized particles can also be used as diagnostic agents, targeted drug delivery vehicle, noninvasive imaging technologies, and in vivo visual monitoring of tumors angiogenesis. These nanomaterials provide a promising platform for diagnostics, prognostic, drug delivery, and treatment of diseases by means of nanoengineered products/devices. This owes to their small size, prolonged antimicrobial efficacy with insignificant toxicity creating less environmental hazard or toxicity. Scientists address several problems such as health, bioethical problems, toxicity risks, physiological, and pharmaceutical concerns related with the usage of NPs as antimicrobial agents as current research lack adequate data and information on the safe use of certain tools and materials.

Zinc oxide and zinc oxide-based nanostructures: biogenic and phytogenic synthesis, properties and applications

Zinc oxide nanoparticles (ZnO NPs) are considered as very significant and essential material due to its multifunctional properties, stability, low cost and wide usage. Many green and biogenic approaches for ZnO NPs synthesis have been reported using various sources such as plants and microorganisms. Plants contain biomolecules that can act as capping, oxidizing and reducing agents that increase the rate of reaction and stabilizes the NPs. This review emphasizes and compiles different types of plants and parts of plant used for the synthesis of ZnO and its potential applications at one place. The influence of biogenic and phytogenic synthesized ZnO on its properties and possible mechanisms for its fabrication has been discussed. This review also highlights the potential applications and future prospects of phytogenic synthesized ZnO in the field of energy production and storage, sun light harvesting, environmental remediation, and biological applications.

Effect of Mg doping on ZnO fabricated using aqueous leaf extract of Ziziphus mauritiana Lam. for antioxidant and antibacterial studies

Aqueous leaf extract of Ziziphus mauritiana Lam. was successfully used to synthesize zinc oxide (ZnO) and magnesium-doped ZnO (Mg-doped ZnO) particles and acted as capping and stabilizing agent. UV-Vis diffuse reflectance spectra showed that optical band gap energy of ZnO has narrowed from 3.11 to 3.08 eV and 3.03 eV when doped with 1% Mg and 5% Mg, respectively. Powder X-ray diffraction and X-ray photoelectron spectroscopy studies confirmed the purity and crystalline nature of the synthesized materials. FT-IR spectroscopy revealed the presence of phytochemicals coated on the surface of synthesized materials. The synthesized materials were found to effectively scavenge DPPH radicals in the presence of visible light in comparison to the dark. The antibacterial properties of the synthesized materials were evaluated against Staphylococcus aureus and Escherichia coli. The obtained results revealed that Staphylococcus aureus seemed to be more sensitive to the green synthesized ZnO and Mg-doped ZnO than Escherichia coli.

Crotalaria verrucosa Leaf Extract Mediated Synthesis of Zinc Oxide Nanoparticles: Assessment of Antimicrobial and Anticancer Activity

In this work, we present an ecofriendly, non-hazardous, green synthesis of zinc oxide nanoparticles (ZnO NPs) by leaf extract of Crotalaria verrucosa (C. verrucosa). Total phenolic content, total flavonoid and total protein contents of C. verrucosa were determined. Further, synthesized ZnO NPs was characterized by UV-visible spectroscopy (UV-vis), X-ray diffractometer (XRD), Fourier transform infra-red (FTIR) Spectra, transmission electron microscope (TEM), and Dynamic light scattering (DLS) analysis. UV-vis shows peak at 375 nm which is unique to ZnO NPs. XRD analysis demonstrates the hexagonal phase structures of ZnO NPs. FTIR spectra demonstrates the molecules and bondings associated with the synthesized ZnO NPs and assures the role of phytochemical compounds of C. verrucosa in reduction and capping of ZnO NPs. TEM image exhibits that the prepared ZnO NPs is hexagonal shaped and in size ranged between 16 to 38 nm which is confirmed by DLS. Thermo-gravimetric analysis (TGA) was performed to determine the thermal stability of biosynthesized nanoparticles during calcination. The prepared ZnO NPs showed significant antibacterial potentiality against Gram-positive (S. aureus) and Gram-negative (Proteus vulgaris, Klebsiella pneumoniae, and Escherichia coli) pathogenic bacteria and SEM image shows the generalized mechanism of action in bacterial cell after NPs internalization. In addition, NPs are also found to be effective against the studied cancer cell lines for which cytotoxicity was assessed using MTT assay and results demonstrate highest growth of inhibition at the concentration of 100 µg/mL with IC50 value at 7.07 µg/mL for HeLa and 6.30 µg/mL for DU145 cell lines, in contrast to positive control (C. verrucosa leaf extract) with IC50 of 22.30 µg/mL on HeLa cells and 15.72 µg/mL on DU145 cells. Also, DAPI staining was performed in order to determine the effect on nuclear material due to ZnO NPs treatment in the studied cell lines taking leaf extract as positive control and untreated negative control for comparison. Cell migration assay was evaluated to determine the direct influence of NPs on metastasis that is potential suppression capacity of NPs to tumor cell migration. Outcome of the synthesized ZnO NPs using C. verrucosa shows antimicrobial activity against studied microbes, also cytotoxicity, apoptotic mediated DNA damage and antiproliferative potentiality in the studied carcinoma cells and hence, can be further used in biomedical, pharmaceutical and food processing industries as an effective antimicrobial and anti-cancerous agent.