Green Synthesis of Metallic Nanoparticles Using Some Selected Medicinal Plants from Southern Africa and Their Biological Applications

Potentials of roots, stems, leaves, flowers, fruits, and seeds extract for the synthesis of silver nanoparticles

Silver nanoparticles (AgNPs) have gained significant attention in various applications due to their unique properties that differ from bulk or macro-sized counterparts. In the advancement of nanotechnology, a reliable, non-toxic, and eco-friendly green synthesis has widely been developed as an alternative method for the production of AgNPs, overcoming limitations associated with the traditional physical and chemical methods. Green synthesis of AgNPs involves the utilization of biological sources including plant extracts with silver salt as the precursor. The potential of phytochemicals in plant extracts serves as a reducing/capping and stabilizing agent to aid in the bio-reduction of Ag+ ions into a stable nanoform, Ag0. This review provides insights into the potentials of various plant parts like root, stem, leaf, flower, fruit, and seed extracts that have been extensively reported for the synthesis of AgNPs.

Recent Trends in Biologically Synthesized Metal Nanoparticles and their Biomedical Applications: a Review

In recent years, biologically synthesized metal nanoparticles have emerged as a dynamic field of research with significant implications for biomedical applications. This review explores the latest trends in the synthesis of metal nanoparticles using biological methods, encompassing plant extracts and microorganisms such as bacteria, yeasts, and fungi. These innovative approaches offer a sustainable, cost-effective, and environmentally friendly alternative to conventional chemical synthesis methods. Moreover, this review delves into the multifaceted biomedical applications of biologically synthesized metal nanoparticles. These applications include drug delivery systems, diagnostics, therapeutics, and imaging technologies, showcasing the versatility and promise of these nanomaterials in addressing contemporary biomedical challenges. In addition, the review addresses the critical issue of cytotoxicity, offering insights into the safety and viability of these biologically derived NPs for medical use. The exploration of recent trends and advancements in this field underscores the transformative potential of biologically synthesized metal nanoparticles in revolutionizing biomedical research and healthcare.

Biogenic metallic nanoparticles: from green synthesis to clinical translation

Biogenic metallic nanoparticles (NPs) have garnered significant attention in recent years due to their unique properties and various applications in different fields. NPs, including gold, silver, zinc oxide, copper, titanium, and magnesium oxide NPs, have attracted considerable interest. Green synthesis approaches, utilizing natural products, offer advantages such as sustainability and environmental friendliness. The theranostics applications of these NPs hold immense significance in the fields of medicine and diagnostics. The review explores intricate cellular uptake pathways, internalization dynamics, reactive oxygen species generation, and ensuing inflammatory responses, shedding light on the intricate mechanisms governing their behaviour at a molecular level. Intriguingly, biogenic metallic NPs exhibit a wide array of applications in medicine, including but not limited to anti-inflammatory, anticancer, anti-diabetic, anti-plasmodial, antiviral properties and radical scavenging efficacy. Their potential in personalized medicine stands out, with a focus on tailoring treatments to individual patients based on these NPs' unique attributes and targeted delivery capabilities. The article culminates in emphasizing the role of biogenic metallic NPs in shaping the landscape of personalized medicine. Harnessing their unique properties for tailored therapeutics, diagnostics and targeted interventions, these NPs pave the way for a paradigm shift in healthcare, promising enhanced efficacy and reduced adverse effects.

Phytonanotherapy for the Treatment of Metabolic Dysfunction-Associated Steatotic Liver Disease

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as nonalcoholic fatty liver disease, is a steatotic liver disease associated with metabolic syndrome (MetS), especially obesity, hypertension, diabetes, hyperlipidemia, and hypertriglyceridemia. MASLD in 43-44% of patients can progress to metabolic dysfunction-associated steatohepatitis (MASH), and 7-30% of these cases will progress to liver scarring (cirrhosis). To date, the mechanism of MASLD and its progression is not completely understood and there were no therapeutic strategies specifically tailored for MASLD/MASH until March 2024. The conventional antiobesity and antidiabetic pharmacological approaches used to reduce the progression of MASLD demonstrated favorable peripheral outcomes but insignificant effects on liver histology. Alternatively, phyto-synthesized metal-based nanoparticles (MNPs) are now being explored in the treatment of various liver diseases due to their unique bioactivities and reduced bystander effects. Although phytonanotherapy has not been explored in the clinical treatment of MASLD/MASH, MNPs such as gold NPs (AuNPs) and silver NPs (AgNPs) have been reported to improve metabolic processes by reducing blood glucose levels, body fat, and inflammation. Therefore, these actions suggest that MNPs can potentially be used in the treatment of MASLD/MASH and related metabolic diseases. Further studies are warranted to investigate the feasibility and efficacy of phytonanomedicine before clinical application.

Green Synthesis, Characterization and Application of Silver Nanoparticles Using Bioflocculant: A Review

Nanotechnology has emerged as an effective means of removing contaminants from water. Traditional techniques for producing nanoparticles, such as physical methods (condensation and evaporation) and chemical methods (oxidation and reduction), have demonstrated high efficiency. However, these methods come with certain drawbacks, including the significant energy requirement and the use of costly and hazardous chemicals that may cause nanoparticles to adhere to surfaces. To address these limitations, researchers are actively developing alternative procedures that are cost-effective, environmentally safe, and user-friendly. One promising approach involves biological synthesis, which utilizes plants or microorganisms as reducing and capping agents. This review discusses various methods of nanoparticle synthesis, with a focus on biological synthesis using naturally occurring bioflocculants from microorganisms. Bioflocculants offer several advantages, including harmlessness, biodegradability, and minimal secondary pollution. Furthermore, the review covers the characterization of synthesized nanoparticles, their antimicrobial activity, and cytotoxicity. Additionally, it explores the utilization of these NPs in water purification and dye removal processes.

Sustainable synthesis of bionanomaterials using non-native plant extracts for maintaining ecological balance: A computational bibliography analysis

Biological approaches via biomolecular extracts of bacteria, fungi, or plants have recently been introduced as an alternative approach to synthesizing less or nontoxic nanomaterials, compared to conventional physical and chemical approaches. Among these biological methods, plant-mediated approaches (phytosynthesis) are reported to be highly beneficial for large-scale, nontoxic nanomaterial synthesis. However, plant-mediated synthesis of nanomaterials using native plant extract can lead to bioprospecting issues and deforestation challenges. On the other hand, non-native or invasive plants are non-indigenous to a particular geographic location that can grow and spread rapidly, ultimately disrupting the local and endogenous plant communities or ecosystems. Thus, controlling or eradicating these non-native plants before they damage the ecosystem is necessary. Even though mechanical, chemical, and biological approaches are available to control non-native plants, all these methods possess certain limitations, such as environmental toxicity, disturbance in the nutrient cycle, and loss of genetic integrity. Therefore, non-native plants were recently proposed as a novel sustainable source of phytochemicals for preparing nanomaterials via green chemistry, mainly metallic nanoparticles, as an alternative to native, agriculture-based, or medicinal plants. This work aims to cover a literature gap on plant-mediated bionanomaterial synthesis with an overview and bibliography analysis of non-native plants via novel data mining and advanced visualization tools. In addition, the potential of non-native plants as a sustainable, green chemistry-based alternative for bionanomaterial preparation for maintaining ecological balance, the mechanism of formation via phytochemicals, and their possible applications to promote their control and spread were also discussed. The bibliography analysis revealed that only an average of 4 articles have been published in the last 10 years (2013-2023) on non-native/invasive plants for nanomaterial synthesis, which shows the significance of this article.

Dietary microalgal-fabricated selenium nanoparticles improve Nile tilapia biochemical indices, immune-related gene expression, and intestinal immunity

BACKGROUND

Feed supplements, including essential trace elements are believed to play an important role in augmenting fish immune response. In this context, selenium nanoparticles (SeNPs) in fish diets via a green biosynthesis strategy have attracted considerable interest. In this investigation, selenium nanoparticles (SeNPs, 79.26 nm) synthesized from the green microalga Pediastrum boryanum were incorporated into Nile tilapia diets to explore its beneficial effects on the immune defense and intestinal integrity, in comparison with control basal diets containing inorganic Se source. Nile tilapia (No. 180, 54-57 g) were fed on three formulated diets at concentrations of 0, 0.75, and 1.5 mg/kg of SeNPs for 8 weeks. After the trial completion, tissue bioaccumulation, biochemical indices, antioxidant and pro-inflammatory cytokine-related genes, and intestinal histological examination were analyzed.

RESULTS

Our finding revealed that dietary SeNPs significantly decreased (P < 0.05) serum alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and cholesterol, while increasing (P < 0.05) high-density lipoproteins (HDL). The Se concentration in the muscle tissues showed a dose-dependent increase. SeNPs at a dose of 1.5 mg/kg significantly upregulated intestinal interleukin 8 (IL-8) and interleukin 1 beta (IL-1β) gene transcription compared with the control diet. Glutathione reductase (GSR) and glutathione synthetase (GSS) genes were significantly upregulated in both SeNPs-supplemented groups compared with the control. No apoptotic changes or cell damages were observed as indicated by proliferating cell nuclear antigen (PCNA) and caspase-3 gene expression and evidenced histopathologically. SeNPs supplementation positively affects mucin-producing goblet cells (GCs), particularly at dose of 1.5 mg/kg.

CONCLUSION

Therefore, these results suggest that Green synthesized SeNPs supplementation has promising effects on enhancing Nile tilapia immunity and maintaining their intestinal health.

Moringa oleifera leaves extract loaded gold nanoparticles offers a promising approach in protecting against experimental nephrotoxicity

Cisplatin is one of the most important antitumor drugs, however; it has numerous adverse effects like nephrotoxicity which is considered one of cisplatin uses . The study was planned to evaluate the nephroprotective effect of M. oleifera leaves extract loaded gold nanoparticles (Au-NPs) against cisplatin-induced nephrotoxicity in rats. Initially, total phenolic contents (TPC) and the antioxidant activity of the M. oleifera leaves extract were evaluated and recorded 8.50 mg/g and 39.89 % respectively. After that, the dry leaves of M. oleifera were grinded into fine powder and extracted using water extraction system. Then, different volumes (0.5, 1 and 2 mL) of M. Oleifera were blended with constant volume of Au-NPs (1 mL). Both Au-NPs and M. oleifera extract loaded Au-NPs were investigated using transmission electron microscope (TEM) that illustrated the deposition of M. Oleifera onto Au-NPs. The experimental study was performed on seventy male albino rats alienated into seven groups. Group I healthy rats, group II injected with one dose of cisplatin (CisPt), groups from III to VII treated groups received CisPt then received M. Oleifera leaves extract alone and /or Au-NPs with different ratios and concentrations. After the experiment' time, serum urea and creatinine, kidney injury molecule-1 (KIM-1), advanced oxidation protein products (AOPP), monocyte chemoattractant protein-1 (MCP-1), tumor necrotic factor-α (TNF-α), and interleukin-6 (IL-6) were evaluated as markers of renal nephrotoxicity. The kidneys of rats were excised for malondialdehyde (MDA), nitric oxide (NO), and superoxide dismutase (SOD) assessments. Induction of CisPt showed a highly significant disturbance in oxidant/anti-oxidant balance and inducing inflammatory cascades supporting nephrotoxicity, while treatment with M. Oleifera leaves extract, Au-NPs, and the different concentrations of the extract loaded on Au-NPs had a crucial role in attenuating oxidative stress, enhancing antioxidant systems, and reducing inflammatory biomarkers, although the most significant results showed a powerful scavenging activity against nephrotoxicity induced by CisPt was obtained with M. Oleifera leaves extract loaded on Au-NPs with a concentration of 2:1 respectively.

Assessment of multi-biomedical efficiency of Andrographis paniculata shoot extracts through in-vitro analysis and major compound identification

The present investigation looked into the various biomedical potentials of Andrographis paniculata shoot extracts. The results showed that the methanol extract (Met-E) of A. paniculata contains more phytochemicals than the acetone and petroleum ether extracts, including alkaloids, saponins, tannins, phenolics, flavonoids, glycosides, terpenoids, phytosterol, steroids, and protein. Accordingly, the Met-E alone showed considerable bactericidal activity (through agar well diffusion method) against the bacterial pathogens namely Shigella dysenteriae, Bacillus cereus, Salmonella typhi, Enterococcus faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphlococcus aureus, E. coli, and B. subtilis. This bactericidal activity was found as dose dependent manner, since at 1000 μg ml concentration, the Met-E showed better antibacterial activity. Similarly, at increased concentration (1000 μg ml) it showed notable antidiabetic (α-amylase inhibition: 74.31% and α-glucosidase inhibition: 72.34%), antioxidant (DPPH: 78.24%), and anti-inflammatory (albumin denaturation inhibition: 79.84% and lipoxigenase inhibition: 69.4%) activities. The phytochemical profiling of Met-E was characterized by UV-visible spectrophotometer (UV-vis), Gas Chromatography-Mass Spectrometry (GC/MS), Fourier transform infrared (FTIR), and High Performance Liquid Chromatography (HPLC) analyses. The results showed the Met-E contain bioactive compounds such as gallic acid, epicatechin, catechin, naringin, vitexin-2-rhamnoside, taxifolin, kaempferol, hesperidin, myricetin, rutin, quercetin, phloretin, and ursolic acid compounds. While most of these substances have been recognised for their pharmacological application perspective, the biological properties of particular substances must be studied in the future using in-vivo strategies.

Induction of Browning in White Adipocytes: Fucoidan Characterization and Gold Nanoparticle Synthesis from Undaria pinnatifida Sporophyll Extract

Seaweed extracts and their specific polysaccharides are widely known for their ability to act as reducing and capping agents during nanoparticle synthesis. Their application is highly favored in green synthesis methods, owing to their eco-friendliness, cost-effectiveness, and remarkable time and energy efficiency. In this study, fucoidan extracted from Undaria pinnatifida sporophyll (UPS) is introduced as a polysaccharide that effectively serves as a dual-function reducing and capping agent for the synthesis of gold nanoparticles (AuNPs). Results from various analyses indicate that AuNPs derived from UPS extract display a uniform spherical shape with an average size of 28.34 ± 1.15 nm and a zeta potential of -37.49 ± 2.13 mV, conclusively confirming the presence of Au. The FT-IR spectra distinctly revealed the characteristic fucoidan bands on the stabilized UPS-AuNPs surface. A 1H-NMR analysis provided additional confirmation by revealing the presence of specific fucoidan protons on the UPS-AuNPs surface. To comprehensively evaluate the impact of UPS extract, UPS-AuNPs, and fucoidan on the biological properties of adipocytes, a rigorous comparative analysis of lipid droplet formation and morphology was conducted. Our findings revealed that adipocytes treated with UPS extract, fucoidan, and UPS-AuNPs, in that order, exhibited a reduction in the total lipid droplet surface area, maximum Ferret diameter, and overall Nile red staining intensity when compared to mature white adipocytes. Furthermore, our analysis of the effects of UPS extracts, UPS-AuNPs, and fucoidan on the expression of key markers associated with white adipose tissue browning, such as UCP1, PGC1a, and PRDM16, demonstrated increased mRNA and protein expression levels in the following order: UPS-AuNPs > fucoidan > UPS extracts. Notably, the production of active mitochondria, which play a crucial role in enhancing energy expenditure in beige adipocytes, also increased in the following order: UPS-AuNPs > fucoidan > UPS extract. These findings underscore the pivotal role of UPS extract, fucoidan, and UPS-AuNPs in promoting adipocyte browning and subsequently enhancing energy expenditure.

Phytochemicals, therapeutic benefits and applications of chrysanthemum flower: A review

Chrysanthemum is a flowering plant belonging to a genus of the dicotyledonous herbaceous annual flowering plant of the Asteraceae (Compositae) family. It is a perpetual flowering plant, mostly cultivated for medicinal purposes; generally, used in popular drinks due to its aroma and flavor. It is primarily cultivated in China, Japan, Europe, and United States. These flowers were extensively used in various healthcare systems and for treating various diseases. Chrysanthemum flowers are rich in phenolic compounds and exhibit strong properties including antioxidant, antimicrobial, anti-inflammatory, anticancer, anti-allergic, anti-obesity, immune regulation, hepatoprotective, and nephroprotective activities. The main aim of the present review was to investigate the nutritional profile, phytochemistry, and biological activities of flowers of different Chrysanthemum species. Also, a critical discussion of the diverse metabolites or bioactive constituents of the Chrysanthemum flowers is highlighted in the present review. Moreover, the flower extracts of Chrysanthemum have been assessed to possess a rich phytochemical profile, including compounds such as cyanidin-3-O-(6″-O-malonyl) glucoside, delphinidin 3-O-(6" -O-malonyl) glucoside-3', rutin, quercetin, isorhamnetin, rutinoside, and others. These profiles exhibit potential health benefits, leading to their utilization in the production of supplementary food products and pharmaceutical drugs within the industry. However, more comprehensive research studies/investigations are still needed to further discover the potential benefits for human and animal utilization.

Silver nanoparticle technology in orthopaedic infections

The irrational and prolonged use of antibiotics in orthopaedic infections poses a major threat to the development of antimicrobial resistance. To combat antimicrobial resistance, researchers have implemented various novel and innovative modalities to curb infections. Nanotechnology involves doping ions/metals onto the scaffolds to reach the target site to eradicate the infective foci. In this connotation, we reviewed silver nanoparticle technology in terms of mechanism of action, clinical applications, toxicity, and regulatory guidelines to treat orthopaedic infections.

Enhanced Antioxidant Activity and Reduced Cytotoxicity of Silver Nanoparticles Stabilized by Different Humic Materials

The current article describes the biological activity of new biomaterials combining the "green" properties of humic substances (HSs) and silver nanoparticles. The aim is to investigate the antioxidant activity (AOA) of HS matrices (macroligands) and AgNPs stabilized with humic macroligands (HS-AgNPs). The unique chemical feature of HSs makes them very promising ligands (matrices) for AgNP stabilization. HSs have previously been shown to exert many pharmacological effects mediated by their AOA. AgNPs stabilized with HS showed a pronounced ability to bind to reactive oxygen species (ROS) in the test with ABTS. Also, higher AOA was observed for HS-AgNPs as compared to the HS matrices. In vitro cytotoxicity studies have shown that the stabilization of AgNPs with the HS matrices reduces the cytotoxicity of AgNPs. As a result of in vitro experiments with the use of 2,7-dichlorodihydrofluorescein diacetate (DCFDA), it was found that all HS materials tested and the HS-AgNPs did not exhibit prooxidant effects. Moreover, more pronounced AOA was shown for HS-AgNP samples as compared to the original HS matrices. Two putative mechanisms of the pronounced AOA of the tested compositions are proposed: firstly, the pronounced ability of HSs to inactivate ROS and, secondly, the large surface area and surface-to-volume ratio of HS-AgNPs, which facilitate electron transfer and mitigate kinetic barriers to the reduction reaction. As a result, the antioxidant properties of the tested HS-AgNPs might be of particular interest for biomedical applications aimed at inhibiting the growth of bacteria and viruses and the healing of purulent wounds.

Eco-Friendly Green Synthesis and Characterization of Silver Nanoparticles by Scutellaria multicaulis Leaf Extract and Its Biological Activities

Scutellaria multicaulis is a medicinal plant indigenous to Iran, Afghanistan, and Pakistan. It has been widely used as a prominent herb in traditional medicine for thousands of years. This plant is reported to contain baicalein, wogonin, and chrysin flavonoids, which are a significant group of chemical ingredients which can cure different diseases, such as breast cancer. S. multicaulis leaf extract was used for the bioreduction of silver nanoparticles (SmL-Ag-NPs), and their phytochemical contents and antioxidant, antibacterial, anti-proliferative, and apoptotic activity were evaluated. Optimal physicochemical properties of SmL-Ag-NPs were obtained by mixing 5% of leaf extract and 2 mM of aqueous AgNO₃ solution and confirmed by characterization studies including UV-visible spectrophotometry, Field Emission Scanning Electron Microscope (FE-SEM), Energy Dispersive X-ray (EDX), Dynamic Light Scattering (DLS), zeta potential, Thermogravimetric analysis (TGA), Surface-enhanced Raman spectroscopy (SERS), X-ray crystallography (XRD), and Fourier transform infrared (FTIR) Spectroscopy. SmL-Ag-NPs exhibited a higher content of total phenol and total flavonoid and potential antioxidant activity. SmL-Ag-NPs also demonstrated dose-dependent cytotoxicity against MDA-MB231 cell multiplication with an IC₅₀ value of 37.62 μg/mL through inducing cell apoptosis. Results show that SmL-Ag-NPs is effective at inhibiting the proliferation of MDA-MB231 cells compared to tamoxifen. This demonstrates that SmL-Ag-NPs could be a bio-friendly and safe strategy to develop new cancer therapies with a reduction in the adverse effects of chemotherapy in the near future.

Eucalyptus globulus Mediated Green Synthesis of Environmentally Benign Metal Based Nanostructures: A Review

The progress in nanotechnology has effectively tackled and overcome numerous global issues, including climate change, environmental contamination, and various lethal diseases. The nanostructures being a vital part of nanotechnology have been synthesized employing different physicochemical methods. However, these methods are expensive, polluting, eco-unfriendly, and produce toxic byproducts. Green chemistry having exceptional attributes, such as cost-effectiveness, non-toxicity, higher stability, environment friendliness, ability to control size and shape, and superior performance, has emerged as a promising alternative to address the drawbacks of conventional approaches. Plant extracts are recognized as the best option for the biosynthesis of nanoparticles due to adherence to the environmentally benign route and sustainability agenda 2030 of the United Nations. In recent decades, phytosynthesized nanoparticles have gained much attention for different scientific applications. Eucalyptus globulus (blue gum) is an evergreen plant belonging to the family Myrtaceae, which is the targeted point of this review article. Herein, we mainly focus on the fabrication of nanoparticles, such as zinc oxide, copper oxide, iron oxide, lanthanum oxide, titanium dioxide, magnesium oxide, lead oxide, nickel oxide, gold, silver, and zirconium oxide, by utilizing Eucalyptus globulus extract and its essential oils. This review article aims to provide an overview of the synthesis, characterization results, and biomedical applications of nanoparticles synthesized using Eucalyptus globulus. The present study will be a better contribution to the readers and the students of environmental research.

Gold nanoparticles synthesis using Gymnosporia montana L. and its biological profile: a pioneer report

BACKGROUND

The forming, blending, and characterization of materials at a size of one billionth of a meter or less is referred to as nanotechnology. The objective of the current study was to synthesize ecologically friendly gold nanoparticles (AuNPs) from Gymnosporia montana L. (G. montana) leaf extract, characterize them, assess their interaction with different types of deoxyribonucleic acid (DNA), and investigate their antioxidant and toxic capabilities.

RESULTS

The biosynthesized AuNPs presence was validated by a color change from yellow to reddish pink as well as using UV-visible spectrophotometer. Fourier transform infrared (FTIR) spectroscopy analysis showed the presence of phytoconstituents like, alcohols, phenols, and nitro compounds responsible for the reduction of AuNPs. Zeta sizer and zeta potential of 559.6 d. nm and - 4.5 mV, respectively, demonstrated potential stability. With an average size between 10 and 50 nm, X-ray diffraction (XRD), and high-resolution transmission electron microscope (HR-TEM), revealed the crystalline formation of AuNPs. Surface topology with 3D characterization, irregular spherical shape, and size with 6.48 nm of AuNPs was determined with the help of an atomic force microscope (AFM). AuNPs with some irregular and spherical shapes, and sizes between 2 and 20 nm, were revealed by field emission scanning electron microscope (FESEM) investigation. Shifts in the spectrum were visible when the bioavailability of AuNPs with calf-thymus DNA (CT-DNA) and Herring sperm DNA (HS-DNA) was tested. Additionally, the DNA nicking assay's interaction with pBR322 DNA confirmed its physiochemical and antioxidant properties. The same was also found by using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, which showed a 70-80% inhibition rate. Finally, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay revealed that viability decreased with increasing dosage, going from 77.74 to 46.99% on MCF-7 cell line.

CONCLUSION

Synthesizing AuNPs through biogenic processes and adopting G. montana for the first time revealed potential DNA interaction, antioxidant, and cytotoxicity capabilities. Thus, opening new possibilities in the turf of therapeutics as well as in other areas.

Antioxidant Activities of Photoinduced Phycogenic Silver Nanoparticles and Their Potential Applications

While various methods exist for synthesizing silver nanoparticles (AgNPs), green synthesis has emerged as a promising approach due to its affordability, sustainability, and suitability for biomedical purposes. However, green synthesis is time-consuming, necessitating the development of efficient and cost-effective techniques to minimize reaction time. Consequently, researchers have turned their attention to photo-driven processes. In this study, we present the photoinduced bioreduction of silver nitrate (AgNO₃) to AgNPs using an aqueous extract of Ulva lactuca, an edible green seaweed. The phytochemicals found in the seaweed functioned as both reducing and capping agents, while light served as a catalyst for biosynthesis. We explored the effects of different light intensities and wavelengths, the initial pH of the reaction mixture, and the exposure time on the biosynthesis of AgNPs. Confirmation of AgNP formation was achieved through the observation of a surface plasmon resonance band at 428 nm using an ultraviolet-visible (UV-vis) spectrophotometer. Fourier transform infrared spectroscopy (FTIR) revealed the presence of algae-derived phytochemicals bound to the outer surface of the synthesized AgNPs. Additionally, high-resolution transmission electron microscopy (HRTEM) and atomic force microscopy (AFM) images demonstrated that the NPs possessed a nearly spherical shape, ranging in size from 5 nm to 40 nm. The crystalline nature of the NPs was confirmed by selected area electron diffraction (SAED) and X-ray diffraction (XRD), with Bragg's diffraction pattern revealing peaks at 2θ = 38°, 44°, 64°, and 77°, corresponding to the planes of silver 111, 200, 220, and 311 in the face-centered cubic crystal lattice of metallic silver. Energy-dispersive X-ray spectroscopy (EDX) results exhibited a prominent peak at 3 keV, indicating an Ag elemental configuration. The highly negative zeta potential values provided further confirmation of the stability of AgNPs. Moreover, the reduction kinetics observed via UV-vis spectrophotometry demonstrated superior photocatalytic activity in the degradation of hazardous pollutant dyes, such as rhodamine B, methylene orange, Congo red, acridine orange, and Coomassie brilliant blue G-250. Consequently, our biosynthesized AgNPs hold great potential for various biomedical redox reaction applications.

Field emission scanning electron microscopic, X-ray diffraction and ultraviolet spectroscopic analysis of Terminalia bellerica based silver nanoparticles and evaluation of their antioxidant, catalytic and antibacterial activity

In recent years, scientists have come up with ways to make nanoparticles that are inexpensive and good for the environment. Terminalia bellerica-based silver nanoparticles (TBAgNPs) were made in this study using methanol extract from T. bellerica fruits. This method was quick, economical, and good for the environment. The biosynthesized TBAgNPs were used as antioxidants, antibacterial agents, and anti-catalytic agents. Analytical techniques like XRD, FESEM, and UV-Vis were used to find out more about the spherical TBAgNPs that were made. Also, Cefotaxime-resistant bacteria found in hospitals were used to test how well the TBAgNPs killed bacteria. With the Bauer-agar Kirby's gel diffusion and Mueller-Hinton broth methods, the ability of the synthesized TBAgNPs to stop bacterial growth was tested. After the TBAgNPs were studied, it was found that the average size of their crystals was between 10 and 25 nm. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) reducing tests showed that these AgNPs could act as antioxidants, and TBAgNPs (%inhibition = 20.90% to 94.94%) were better antioxidant than ascorbic acid (%inhibition = 13.80% to 86.10%) and extract (%inhibition = 16.90% to 80.50%). The reduction of methylene blue (MB) to leucomethylene blue (LMB) with sodium borohydride (NaBH₄) was used as a model to test the catalytic potential of TBAgNPs. On UV spectroscopic analysis at room temperature, TBAgNPs at different concentrations were able to reduce methylene blue effectively. For Escherichia coli and Klebsiella pneumoniae, the minimum inhibitory concentration (MIC) for TBAgNPs was 0.625 μg/mL and 1.25 μg/mL, respectively. Based on these results, silver nanoparticles made with Terminalia bellerica extract may have much biological importance and could be used in making useful therapeutic applications.

Phytogenically Synthesized Zinc Oxide Nanoparticles (ZnO-NPs) Potentially Inhibit the Bacterial Pathogens: In Vitro Studies

The usefulness of nanoparticles (NPs) in biological applications, such as nanomedicine, is becoming more widely acknowledged. Zinc oxide nanoparticles (ZnO-NPs) are a type of metal oxide nanoparticle with an extensive use in biomedicine. Here, ZnO-NPs were synthesized using Cassia siamea (L.) leaf extract and characterized using state-of-the-art techniques; UV-vis spectroscopy, XRD, FTIR, and SEM. At sub-minimum inhibitory concentration (MIC) levels, the ability of ZnO@Cs-NPs to suppress quorum-mediated virulence factors and biofilm formation against clinical MDR isolates (Pseudomonas aeruginosa PAO1 and Chromobacterium violaceum MCC-2290) was tested. The ½MIC of ZnO@Cs-NPs reduced violacein production by C. violaceum. Furthermore, ZnO@Cs-NPs sub-MIC significantly inhibited virulence factors such aspyoverdin, pyocyanin, elastase, exoprotease, rhamnolipid, and the swimming motility of P. aeruginosa PAO1 by 76.9, 49.0, 71.1, 53.3, 89.5, and 60%, respectively. Moreover, ZnO@Cs-NPs also showed wide anti-biofilm efficacy, inhibiting a maximum of 67 and 56% biofilms in P. aeruginosa and C. violaceum, respectively. In addition, ZnO@Cs-NPs suppressed extra polymeric substances (EPS) produced by isolates. Additionally, under confocal microscopy, propidium iodide-stained cells of P. aeruginosa and C. violaceum show ZnO@Cs-NP-induced impairment in membrane permeability, revealing strong anti-bacterial efficacy. This research demonstrates that newly synthesized ZnO@Cs-NPs demonstrate a strong efficacy against clinical isolates. In a nutshell, ZnO@Cs-NPs can be used as an alternative therapeutic agent for managing pathogenic infections.

Reports of Plant-Derived Nanoparticles for Prostate Cancer Therapy

Plants have demonstrated potential in providing various types of phytomedicines with chemopreventive properties that can combat prostate cancer. However, despite their promising in vitro activity, the incorporation of these phytochemicals into the market as anticancer agents has been hindered by their poor bioavailability, mainly due to their inadequate aqueous solubility, chemical instability, and unsatisfactory circulation time. To overcome these drawbacks, it has been suggested that the incorporation of phytochemicals as nanoparticles can offer a solution. The use of plant-based chemicals can also improve the biocompatibility of the formulated nanoparticles by avoiding the use of certain hazardous chemicals in the synthesis, leading to decreased toxicity in vivo. Moreover, in some cases, phytochemicals can act as targeting agents to tumour sites. This review will focus on and summarize the following points: the different types of nanoparticles that contain individual phytochemicals or plant extracts in their design with the aim of improving the bioavailability of the phytochemicals; the therapeutic evaluation of these nanoparticles against prostate cancer both in vitro and in vivo and the reported mode of action and the different types of anticancer experiments used; how the phytochemicals can also improve the targeting effects of these nanoparticles in some instances; and the potential toxicity of these nanoparticles.

Nutritional and pharmacological potentials of orphan legumes: Subfamily faboideae

Legumes are a major food crop in many developing nations. However, orphan or underutilized legumes are domesticated legumes that have valuable properties but are less significant than main legumes due to use and supply restrictions. Compared to other major legumes, they are better suited to harsh soil and climate conditions, and their great tolerance to abiotic environmental circumstances like drought can help to lessen the strains brought on by climate change. Despite this, their economic significance in international markets is relatively minimal. This article is aimed at carrying out a comprehensive review of the nutritional and pharmacological benefits of orphan legumes from eight genera in the sub-family Faboidea, namely Psophocarpus Neck. ex DC., Tylosema (Schweinf.) Torre Hillc., Vigna Savi., Vicia L., Baphia Afzel. ex G. Lodd., Mucuna Adans, Indigofera L. and Macrotyloma (Wight & Arn.) Verdc, and the phytoconstituents that have been isolated and characterized from these plants. A literature search was conducted using PubMed, Google Scholar, and Science Direct for articles that have previously reported the relevance of underutilized legumes. The International Union for Conservation of Nature (IUCN) red list of threatened species was also conducted for the status of the species. References were scrutinized and citation searches were performed on the study. The review showed that many underutilized legumes have a lot of untapped potential in terms of their nutritional and pharmacological activities. The phytoconstituents from plants in the subfamily Faboideae could serve as lead compounds for drug discovery for the treatment of a variety of disorders, indicating the need to explore these plant species.

El-Tohamy M, A. Alhwaiti S. Advanced polymeric metal/metal oxide bionanocomposite using seaweed Laurencia dendroidea extract for antiprotozoal, anticancer, and photocatalytic applications

Background

Biosynthesized nanoparticles are gaining popularity due to their distinctive biological applications as well as bioactive secondary metabolites from natural products that contribute in green synthesis.

Methodology

This study reports a facile, ecofriendly, reliable, and cost-effective synthesis of silver nanoparticles (AgNPs), copper oxide nanoparticles (CuONPs), and polymeric PVP-silver-copper oxide nanocomposite using ethanol extract of seaweed Laurencia dendroidea and were evaluated for antiprotozoal, anticancer and photocatalytic potential. The nanostructures of the AgNPs, CuONPs, and polymeric PVP-Ag-CuO nanocomposite were confirmed by different spectroscopic and microscopic procedures.

Results

The UV-vis spectrum displayed distinct absorption peaks at 440, 350, and 470 nm for AgNPs, CuONPs, and polymeric Ag-CuO nanocomposite, respectively. The average particles size of the formed AgNPs, CuONPs, and Ag-CuO nanocomposite was 25, 28, and 30 nm, respectively with zeta potential values -31.7 ± 0.6 mV, -17.6 ± 4.2 mV, and -22.9 ± 4.45 mV. The microscopic investigation of biosynthesized nanomaterials revealed a spherical morphological shape with average crystallite sizes of 17.56 nm (AgNPs), 18.21 nm (CuONPs), and 25.46 nm (PVP-Ag-CuO nanocomposite). The antiprotozoal potential of green synthesized nanomaterials was examined against Leishmania amazonensis and Trypanosoma cruzi parasites. The polymeric PVP-Ag-CuO nanocomposite exerted the highest antiprotozoal effect with IC₅₀ values of 17.32 ± 1.5 and 17.48 ± 4.2 µM, in contrast to AgNPs and CuONPs. The anticancer potential of AgNPs, CuONPs, and polymeric PVP-Ag-CuO nanocomposite against HepG2 cancer cell lines revealed that all the nanomaterials were effective and the highest anticancer potential was displayed by PVP-Ag-CuO nanocomposite with IC₅₀ values 91.34 µg mL^-1 at 200 µg mL^-1 concentration. Additionally, PVP-Ag-CuO nanocomposite showed strong photocatalytic effect.

Conclusion

Overall, this study suggested that the biogenic synthesized nanomaterials AgNPs, CuONPs, and polymeric PVP-Ag-CuO nanocomposite using ethanol extract of seaweed L. dendroidea possesses promising antiprotozoal anticancer and photocatalytic effect and could be further exploited for the development of antiprotozoal and anticancer therapeutics agents.

A critical review on the bio-mediated green synthesis and multiple applications of magnesium oxide nanoparticles

Nowadays, advancements in nanotechnology have efficiently solved many global problems, such as environmental pollution, climate change, and infectious diseases. Nano-scaled materials have played a central role in this evolution. Chemical synthesis of nanomaterials, however, required hazardous chemicals, unsafe, eco-unfriendly, and cost-ineffective, calling for green synthesis methods. Here, we review the green synthesis of MgO nanoparticles and their applications in biochemical, environmental remediation, catalysis, and energy production. Green MgO nanoparticles can be safely produced using biomolecules extracted from plants, fungus, bacteria, algae, and lichens. They exhibited fascinating and unique properties in morphology, surface area, particle size, and stabilization. Green MgO nanoparticles served as excellent antimicrobial agents, adsorbents, colorimetric sensors, and had enormous potential in biomedical therapies against cancers, oxidants, diseases, and the sensing detection of dopamine. In addition, green MgO nanoparticles are of great interests in plant pathogens, phytoremediation, plant cell and organ culture, and seed germination in the agricultural sector. This review also highlighted recent advances in using green MgO nanoparticles as nanocatalysts, nano-fertilizers, and nano-pesticides. Thanks to many emerging applications, green MgO nanoparticles can become a promising platform for future studies.

Green Synthesis of Antibacterial Silver Nanocolloids with Agroindustrial Waste Extracts, Assisted by LED Light

Herein, the green synthesis of silver nanoparticles (AgNPs), assisted by LED light, using the aqueous extracts of agroindustrial waste products, such as avocado seeds (ASs), cocoa pod husks (CPHs), and orange peels (OPs), is presented. Surface plasmon resonance analysis showed faster and complete NP formation when irradiated with blue LED light. Green and red light irradiation showed non- and limited nanoparticle formation. TEM analyses confirmed the semispherical morphology of the synthesized AgNPs, with the exception of OP–AgNPs, which showed agglomeration during the light irradiation. For AS–AgNPs and CPH–AgNPs, the average particle diameter was about 15 nm. Interestingly, the CPH extract demonstrated faster nanoparticle formation as compared to the AS extract (100 min vs. 250 min irradiation time, respectively). FTIR spectroscopy assessed the involvement of diverse functional groups of the bioactive phytochemicals present in the plant extracts during nanoparticle photobiosynthesis. The antioxidant activity, as determined by ferric reducing antioxidant power (FRAP) assay, varied from 1323.72 µmol TE/mL in the AS aqueous extract to 836.50 µmol TE/mL in the CPH aqueous extract. The total polyphenol content was determined according to the Folin–Ciocalteu procedure; the AS aqueous extract exhibited a higher polyphenol content (1.54 mg GAE/g) than did the CPH aqueous extract (0.948 mg GAE/g). In vitro antibacterial assays revealed that the AS–AgNPs exhibited promising antibacterial properties against pathogenic bacteria (E. Coli), whereas the CPH–AgNPs showed antibacterial activity against S. aureus and E. coli. The green synthesis of AgNPs using AS, CPH, and OP aqueous extracts reported in this work is environmentally friendly and cost-effective, and it paves the way for future studies related to agroindustrial waste valorization for the production of advanced nanomaterials, such as antibacterial AgNPs, for potential biomedical, industrial, and environmental applications.

Mycosynthesis of Metal-Containing Nanoparticles-Fungal Metal Resistance and Mechanisms of Synthesis

In the 21st century, nanomaterials play an increasingly important role in our lives with applications in many sectors, including agriculture, biomedicine, and biosensors. Over the last two decades, extensive research has been conducted to find ways to synthesise nanoparticles (NPs) via mediation with fungi or fungal extracts. Mycosynthesis can potentially be an energy-efficient, highly adjustable, environmentally benign alternative to conventional physico-chemical procedures. This review investigates the role of metal toxicity in fungi on cell growth and biochemical levels, and how their strategies of resistance, i.e., metal chelation, biomineral formation, biosorption, bioaccumulation, compartmentalisation, and efflux of metals from cells, contribute to the synthesis of metal-containing NPs used in different applications, e.g., biomedical, antimicrobial, catalytic, biosensing, and precision agriculture. The role of different synthesis conditions, including that of fungal biomolecules serving as nucleation centres or templates for NP synthesis, reducing agents, or capping agents in the synthesis process, is also discussed. The authors believe that future studies need to focus on the mechanism of NP synthesis, as well as on the influence of such conditions as pH, temperature, biomass, the concentration of the precursors, and volume of the fungal extracts on the efficiency of the mycosynthesis of NPs.

The Use of Medicinal Plant-Derived Metallic Nanoparticles in Theranostics

In the quest to effectively diagnose and treat the diseases that afflict mankind, the development of a tool capable of simultaneous detection and treatment would provide a significant cornerstone for the survival and control of these diseases. Theranostics denotes a portmanteau of therapeutics and diagnostics which simultaneously detect and treat ailments. Research advances have initiated the advent of theranostics in modern medicine. Overall, theranostics are drug delivery systems with molecular or targeted imaging agents integrated into their structure. The application of theranostics is rising exponentially due to the urgent need for treatments that can be utilized for diagnostic imaging as an aid in precision and personalised medicine. Subsequently, the emergence of nanobiotechnology and the green synthesis of metallic nanoparticles (MNPs) has provided one such avenue for nanoscale development and research. Of interest is the drastic rise in the use of medicinal plants in the synthesis of MNPs which have been reported to be potentially effective in the diagnosis and treatment of diseases. At present, medicinal plant-derived MNPs have been cited to have broad pharmacological applications and have been studied for their potential use in the treatment and management of cancer, malaria, microbial and cardiovascular diseases. The subject of this article regards the role of medicinal plants in the synthesis of MNPs and the potential role of MNPs in the field of theranostics.

Biomedical Applications of Plant Extract-Synthesized Silver Nanoparticles

Silver nanoparticles (AgNPs) have attracted a lot of interest directed towards biomedical applications due in part to their outstanding anti-microbial activities. However, there have been many health-impacting concerns about their traditional synthesis methods, i.e., the chemical and physical methods. Chemical methods are commonly used and contribute to the overall toxicity of the AgNPs, while the main disadvantages of physical synthesis include high production costs and high energy consumption. The biological methods provide an economical and biocompatible option as they use microorganisms and natural products in the synthesis of AgNPs with exceptional biological properties. Plant extract-based synthesis has received a lot of attention and has been shown to resolve the limitations associated with chemical and physical methods. AgNPs synthesized using plant extracts provide a safe, cost-effective, and environment-friendly approach that produces biocompatible AgNPs with enhanced properties for use in a wide range of applications. The review focused on the use of plant-synthesized AgNPs in various biomedical applications as anti-microbial, anti-cancer, anti-inflammatory, and drug-delivery agents. The versatility and potential use of green AgNPs in the bio-medicinal sector provides an innovative alternative that can overcome the limitations of traditional systems. Thus proving green nanotechnology to be the future for medicine with continuous progress towards a healthier and safer environment by forming nanomaterials that are low- or non-toxic using a sustainable approach.

Marine Algae Extract (Grateloupia Sparsa) for the Green Synthesis of Co3O4NPs: Antioxidant, Antibacterial, Anticancer, and Hemolytic Activities

The aqueous extract of red algae was used for bio-inspired manufacturing of cobalt oxide nanoparticles (Co3O4NPs) and for antioxidant, antibacterial, hemolytic potency, and anticancer activity. Typical, characterization techniques include UV-Vis, SEM, EDAX, TEM, FTIR, XRD, and TGA. Using an X-ray diffraction assay, the size of the Co3O4NPs crystal was determined to range from 23.2 to 11.8 nm. Based on TEM and SEM pictures, biosynthesized Co3O4NPs' had a homogeneous spherical morphology with a 28.8 to 7.6 nm average diameter. Furthermore, Co3O4NPs biological properties were investigated, including determining the antibacterial potency using the zone of inhibition (ZOI) method and determining the minimal inhibitory concentration (MIC). The antibacterial activity of Co3O4NPs was higher than that of the ciprofloxacin standard. Alternatively, scavenging of DPPH free radical investigation was carried out to test the antioxidant capacitance of Co3O4NPs, revealing significant antioxidant ability. The biosynthesized Co3O4NPs have a dose-dependent effect on erythrocyte viability, indicating that this technique is harmless. Furthermore, bioinspired Co3O4NPs effectively against HepG2 cancer cells (IC50: 201.3 μg/ml). Co3O4NPs would be a therapeutic aid due to their antioxidant, antibacterial, and anticancer properties.

A Review of the Green Synthesis of ZnO Nanoparticles Utilising Southern African Indigenous Medicinal Plants

Metal oxide nanoparticles (NPs), such as zinc oxide (ZnO), have been researched extensively for applications in biotechnology, photovoltaics, photocatalysis, sensors, cosmetics, and pharmaceuticals due to their unique properties at the nanoscale. ZnO NPs have been fabricated using conventional physical and chemical processes, but these techniques are limited due to the use of hazardous chemicals that are bad for the environment and high energy consumption. Plant-mediated synthesis of ZnO NPs has piqued the interest of researchers owing to secondary metabolites found in plants that can reduce Zn precursors and stabilise ZnO NPs. Thus, plant-mediated synthesis of ZnO NPs has become one of the alternative green synthesis routes for the fabrication of ZnO NPs. This is attributable to its environmental friendliness, simplicity, and the potential for industrial-scale expansion. Southern Africa is home to a large and diverse indigenous medicinal plant population. However, the use of these indigenous medicinal plants for the preparation of ZnO NPs is understudied. This review looks at the indigenous medicinal plants of southern Africa that have been used to synthesise ZnO NPs for a variety of applications. In conclusion, there is a need for more exploration of southern African indigenous plants for green synthesis of ZnO NPs.

Recent Advances in Silver Nanoparticles Containing Nanofibers for Chronic Wound Management

Infections are the primary cause of death from burns and diabetic wounds. The clinical difficulty of treating wound infections with conventional antibiotics has progressively increased and reached a critical level, necessitating a paradigm change for enhanced chronic wound care. The most prevalent bacterium linked with these infections is Staphylococcus aureus, and the advent of community-associated methicillin-resistant Staphylococcus aureus has posed a substantial therapeutic challenge. Most existing wound dressings are ineffective and suffer from constraints such as insufficient antibacterial activity, toxicity, failure to supply enough moisture to the wound, and poor mechanical performance. Using ineffective wound dressings might prolong the healing process of a wound. To meet this requirement, nanoscale scaffolds with their desirable qualities, which include the potential to distribute bioactive agents, a large surface area, enhanced mechanical capabilities, the ability to imitate the extracellular matrix (ECM), and high porosity, have attracted considerable interest. The incorporation of nanoparticles into nanofiber scaffolds constitutes a novel approach to “nanoparticle dressing” that has acquired significant popularity for wound healing. Due to their remarkable antibacterial capabilities, silver nanoparticles are attractive materials for wound healing. This review focuses on the therapeutic applications of nanofiber wound dressings containing Ag-NPs and their potential to revolutionize wound healing.

Green Synthesis of Hexagonal Silver Nanoparticles Using a Novel Microalgae Coelastrella aeroterrestrica Strain BA_Chlo4 and Resulting Anticancer, Antibacterial, and Antioxidant Activities

Microalgae-mediated synthesis of nanoparticles (NPs) is an emerging nanobiotechnology that utilizes the biomolecular corona of microalgae as reducing and capping agents for NP fabrication. This study screened a novel microalgal strain for its potential to synthesize silver (Ag)-NPs and then assayed the biological activities of the NPs. Coelastrella aeroterrestrica strain BA_Chlo4 was isolated, purified, and morphologically and molecularly identified. Chemical composition of the algal extract was determined by GC-MS analysis. Ag-NPs were biosynthesized by C. aeroterrestrica BA_Chlo4 (C@Ag-NPs) and characterized using various techniques. Antiproliferative activity and the biocidal effect of C@Ag-NPs, C. aeroterrestrica algal extract, and chemically synthesized Ag-NPs (Ch@Ag-NPs) were explored, and the scavenging activity of C@Ag-NPs against free radicals was investigated. C@Ag-NPs were hexagonal, with a nanosize diameter of 14.5 ± 0.5 nm and a maximum wavelength at 404.5 nm. FTIR and GC-MS analysis demonstrated that proteins and polysaccharide acted as capping and reducing agents for C@Ag-NPs. X-ray diffraction, energy diffraction X-ray, and mapping confirmed the crystallinity and natural structure of C@Ag-NPs. The hydrodynamic diameter and charge of C@Ag-NPs was 28.5 nm and −33 mV, respectively. C@Ag-NPs showed significant anticancer activity towards malignant cells, with low toxicity against non-cancerous cells. In addition, C@Ag-NPs exhibited greater antioxidant activity and inhibitory effects against Gram-positive and -negative bacteria compared with the other tested treatments. These findings demonstrate, for first time, the potential of a novel strain of C. aeroterrestrica to synthesize Ag-NPs and the potent antioxidant, anticancer, and biocidal activities of these NPs.

Comparative evaluation of biomedical and phytochemical applications of zinc nanoparticles by using Fagonia cretica extracts

The use of the green approach for nanoparticle synthesis yielded noticeable concern due to its eco-friendliness, cost-effectiveness, and reduced production of toxic chemicals. The current study was designed to formulate Zinc oxide nanoparticles (ZnO NPs) by using Fagonia cretica extracts, evaluating its phytochemical content, and different biological activities. Four different solvents; methanol (MeOH), n-Hexane (n–H), aqueous (Aq), and ethyl acetate (EA), had been utilized in the extracting method. ZnO NPs were successfully synthesized and characterized by UV–vis spectroscopy and scanning electron microscopy (SEM). The UV–vis spectra showed absorbance peaks between 350–400 nm range and SEM analysis revealed spherical morphology with particle sizes ranging from 65–80 nm. In phytochemical analysis, crude extracts exhibited the highest phytochemical content as they contain enriched secondary metabolites. n-hexane extract showed the highest phenolic contents while aqueous extracts showed the highest flavonoid content. Maximum free radicle scavenging activity was observed in NPs synthesized from ethyl-acetate extract with an IC₅₀ value of 35.10 µg/ml. Significant antibacterial activity was exhibited by NPs polar solvents against K. pneumonae, E. coli, and B. subtilis. Polar solvents showed considerable antifungal potential against A. flavus and F. solani. NPs synthesized from nH extract showed potential cytotoxic activity with an LC₅₀ value of 42.41 µg/ml against brine shrimps. A noteworthy antidiabetic activity was exhibited by nanoparticles synthesized from methanol extract i.e., 52.61 ± 0.36%. Significant bald zones were observed in nanoparticles synthesized from methanol extract rendering protein kinase inhibition. The present study highlights the significance of F. indica as a natural source for synthesizing functional nanoparticles with substantial antioxidant, antimicrobial, cytotoxic, protein kinase inhibitory, and antidiabetic properties.

Comparative Evaluation of Biomedical Applications of Zinc Nanoparticles Synthesized by Using Withania somnifera Plant Extracts

Green synthesis of metal nanoparticles is of great importance in the modern health care system. In this study, zinc nanoparticles (ZnONPs) were synthesized using leaf and root extracts of Withania somnifera using four different solvents. ZnONPs were characterized by UV-vis spectrophotometer with a range between 350–400 nm. Scanning electron microscope revealed spherical morphology with an overall size of 70–90 nm and XRD pattern confirmed the crystalline structure. The total flavonoids, phenolic, and alkaloid contents were significantly greater in the crude extracts as compared to ZnONPs. The highest scavenging activity was observed in ZnONPs from n-hexane and ethyl-acetate extracts of roots with IC₅₀ values of 27.36 µg/mL and 39.44 µg/mL, respectively. ZnONPs from methanol and aqueous extracts showed significant antibacterial activity against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis while none of the extracts were found to have significant antifungal activity. Maximum cytotoxic activity was observed in ZnONPs synthesized from aqueous and n-hexane root extracts with LC₅₀ values of 9.36 µg/mL and 18.84 µg/mL, respectively. The highest antidiabetic potential was exhibited by ZnONPs from n-hexane leaf extracts, i.e., 47.67 ± 0.25%. Maximum protein kinase inhibitory potential was observed in ZnONPs of ethyl-acetate extract of roots with a bald zone of 12 mm. These results indicated that Withania somnifera-based ZnONPs showed significant biological activities compared to crude extracts. These findings can further be utilized for in-vivo analysis of nano-directed drug delivery systems.

Fabrication of anti-bacterial cotton bandage using biologically synthesized nanoparticles for medical applications

Recently the use of plant-derived extracts for the green synthesis of nanoparticles has drawn considerable attention. In the present study silver and copper nanoparticles were synthesized using extracts of Andrographis paniculata which is found to possess various pharmacological properties. The synthesized nanoparticles were characterized using UV spectroscopy, SEM with EDS, XRD, TEM and DLS. Furthermore, an attempt is made to impregnate these nanoparticles onto cotton bandages. The structure and morphology of silver nanoparticles impregnated onto the cotton bandages were confirmed by SEM. The anti-bacterial activity of cotton bandages loaded with silver and copper nanoparticles was tested against Escherichia coli, Bacillus cereus, and Staphylococcus aureus using a modified disc diffusion assay. The results indicate that the cotton bandages biofabricated with nanoparticles exhibited anti-bacterial activity in terms of zone of inhibition of growth of tested bacteria suggesting their usage as medical textiles in various biomedical applications for the prevention of infections. Hence, the nanoparticles impregnated cotton fibers can be applied for the development of masks, aprons, etc. to protect against bacterial penetration and as well to counteract the present situation of the world.

Nano-Drug Delivery Systems Entrapping Natural Bioactive Compounds for Cancer: Recent Progress and Future Challenges

Cancer is a prominent cause of mortality globally, and it becomes fatal and incurable if it is delayed in diagnosis. Chemotherapy is a type of treatment that is used to eliminate, diminish, or restrict tumor progression. Chemotherapeutic medicines are available in various formulations. Some tumors require just one type of chemotherapy medication, while others may require a combination of surgery and/or radiotherapy. Treatments might last from a few minutes to many hours to several days. Each medication has potential adverse effects associated with it. Researchers have recently become interested in the use of natural bioactive compounds in anticancer therapy. Some phytochemicals have effects on cellular processes and signaling pathways with potential antitumor properties. Beneficial anticancer effects of phytochemicals were observed in both in vivo and in vitro investigations. Encapsulating natural bioactive compounds in different drug delivery methods may improve their anticancer efficacy. Greater in vivo stability and bioavailability, as well as a reduction in undesirable effects and an enhancement in target-specific activity, will increase the effectiveness of bioactive compounds. This review work focuses on a novel drug delivery system that entraps natural bioactive substances. It also provides an idea of the bioavailability of phytochemicals, challenges and limitations of standard cancer therapy. It also encompasses recent patents on nanoparticle formulations containing a natural anti-cancer molecule.

Recent Developments in Metallic Nanomaterials for Cancer Therapy, Diagnosing and Imaging Applications

Cancer continues to represent a global health concern, imposing an ongoing need to research for better treatment alternatives. In this context, nanomedicine seems to be the solution to existing problems, bringing unprecedented results in various biomedical applications, including cancer therapy, diagnosing, and imaging. As numerous studies have uncovered the advantageous properties of various nanoscale metals, this review aims to present metal-based nanoparticles that are most frequently employed for cancer applications. This paper follows the description of relevant nanoparticles made of metals, metal derivatives, hybrids, and alloys, further discussing in more detail their potential applications in cancer management, ranging from the delivery of chemotherapeutics, vaccines, and genes to ablative hyperthermia therapies and theranostic platforms.

Phytochemicals Mediated Synthesis of AuNPs from Citrullus colocynthis and Their Characterization

Engineered nanoparticles that have distinctive targeted characteristics with high potency are modernistic technological innovations. In the modern era of research, nanotechnology has assumed critical importance due to its vast applications in all fields of science. Biologically synthesized nanoparticles using plants are an alternative to conventional methods. In the present study, Citrullus colocynthis (bitter apple) was used for the synthesis of gold nanoparticles (AuNPs). UV-Vis's spectroscopy, XRD, SEM and FTIR were performed to confirm the formation of AuNPs. UV-Vis's spectra showed a characteristic peak at the range of 531.5-541.5 nm. XRD peaks at 2 θ = 38°, 44°, 64° and 77°, corresponding to 111, 200, 220 and 311 planes, confirmed the crystalline nature of AuNPs. Spherical AuNPs ranged mostly between 7 and 33 nm, and were measured using SEM. The FTIR analysis confirmed the presence of phytochemicals on the surface of AuNPs. Successful synthesis of AuNPs by seed extract of Citrullus colocynthis (bitter apple) as a capping and reducing agent represents the novelty of the present study.

In Vivo Analgesic, Anti-Inflammatory, and Anti-Diabetic Screening of Bacopa monnieri-Synthesized Copper Oxide Nanoparticles

In this work, an ecofriendly approach for biogenic production of copper oxide nanoparticles (CuO-NPs) was proposed by utilizing the Bacopa monnieri leaf extract as a reducing and stabilizing agent. The synthesis of CuO-NPs was instantly confirmed by a shift in the color of the copper solution from blue to dark gray. The use of UV-visible spectroscopy revealed a strong narrow peak at 535 nm, confirming the existence of monoclinic-shaped nanoparticles. The average size of CuO-NPs was 34.4 nm, according to scanning electron microscopy and transmission electron microscopy studies. The pristine crystalline nature of CuO-NPs was confirmed by X-ray diffraction. The monoclinic form of CuO-NPs with a crystallite size of 22 nm was determined by the sharp narrow peaks corresponding to 273, 541, 698, 684, and 366 Bragg's planes at different 2θ values. The presence of different reducing metabolites on the surface of CuO was shown by Fourier transform infrared analysis. The biological efficacy of CuO-NPs was tested against Helicobacter felis, Helicobacter suis, Helicobacter salomonis. and Helicobacter bizzozeronii. H. suis was the most susceptible strain with an inhibition zone of 15.84 ± 0.89 mm at 5 mg/mL of NPs, while the most tolerant strain was H. bizzozeronii with a 13.11 ± 0.83 mm of inhibition zone. In in vivo analgesic activity, CuO-NPs showed superior efficiency compared to controls. The maximum latency time observed was 7.14 ± 0.12 s at a dose level of 400 mg/kg after 90 min, followed by 5.21 ± 0.29 s at 400 mg/kg after 60 min, demonstrating 65 and 61% of analgesia, respectively. Diclofenac sodium was used as a standard with a latency time of 8.6 ± 0.23 s. The results observed in the rat paw edema assays showed a significant inhibitory activity of the plant-mediated CuO-NPs. The percentage inhibition of edema was 74% after 48 h for the group treated with CuO-NPs compared to the control group treated with diclofenac (100 mg/kg) with 24% edema inhibition. The solution of CuO-NPs produced 82% inhibition of edema after 21 days when compared with that of the standard drug diclofenac (73%). CuO-NPs vividly lowered glucose levels in STZ-induced diabetic mice, according to our findings. Blood glucose levels were reduced by about 33.66 and 32.19% in CuO-NP and (CuO-NP + insulin) groups of mice, respectively. From the abovementioned calculations, we can easily conclude that B. monnieri-synthesized CuO-NPs will be a potential antibacterial, anti-diabetic, and anti-inflammatory agent on in vivo and in vitro basis.

Plant Extract-Synthesized Silver Nanoparticles for Application in Dental Therapy

Oral diseases are the most common non-communicable diseases in the world, with dental caries and periodontitis causing major health and social problems. These diseases can progress to systematic diseases and cause disfigurement when left untreated. However, treatment of oral diseases is among the most expensive treatments and often focus on restoration of form and function. Caries prevention has traditionally relied on oral hygiene and diet control, among other preventive measures. In this paper, these measures are not disqualified but are brought into a new context through the use of nanotechnology-based materials to improve these conventional therapeutic and preventive measures. Among inorganic nanomaterials, silver nanoparticles (AgNPs) have shown promising outcomes in dental therapy, due to their unique physicochemical properties and enhanced anti-bacterial activities. As such, AgNPs may provide newer strategies for treatment and prevention of dental infections. However, numerous concerns around the chemical synthesis of nanomaterials, which are not limited to cost and use of toxic reducing agents, have been raised. This has inspired the green synthesis route, which uses natural products as reducing agents. The biogenic AgNPs were reported to be biocompatible and environmentally friendly when compared to the chemically-synthesized AgNPs. As such, plant-synthesized AgNPs can be used as antimicrobial, antifouling, and remineralizing agents for management and treatment of dental infections and diseases.

Broad Spectrum Anti-Bacterial Activity and Non-Selective Toxicity of Gum Arabic Silver Nanoparticles

Silver nanoparticles (AgNPs) are the most commercialized nanomaterials and presumed to be biocompatible based on the biological effects of the bulk material. However, their physico-chemical properties differ significantly to the bulk materials and are associated with unique biological properties. The study investigated the antimicrobial and cytotoxicity effects of AgNPs synthesized using gum arabic (GA), sodium borohydride (NaBH₄), and their combination as reducing agents. The AgNPs were characterized using ultraviolet-visible spectrophotometry (UV-Vis), dynamic light scattering (DLS), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR). The anti-bacterial activity was assessed using agar well diffusion and microdilution assays, and the cytotoxicity effects on Caco-2, HT-29 and KMST-6 cells using MTT assay. The GA-synthesized AgNPs (GA-AgNPs) demonstrated higher bactericidal activity against all bacteria, and non-selective cytotoxicity towards normal and cancer cells. AgNPs reduced by NaBH₄ (C-AgNPs) and the combination of GA and NaBH₄ (GAC-AgNPs) had insignificant anti-bacterial activity and cytotoxicity at ≥50 µg/mL. The study showed that despite the notion that AgNPs are safe and biocompatible, their toxicity cannot be overruled and that their toxicity can be channeled by using biocompatible polymers, thereby providing a therapeutic window at concentrations that are least harmful to mammalian cells but toxic to bacteria.

Biogenic proficient synthesis of (Au-NPs) via aqueous extract of Red Dragon Pulp and seed oil: Characterization, antioxidant, cytotoxic properties, anti-diabetic anti-inflammatory, anti-Alzheimer and their anti-proliferative potential against cancer cell lines

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Novel Green synthesis of Au-NPs using Dragon fruit pulp and seed oil extract for the first time.

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Use of green and safer protocol for synthesis of Au-NPs further demonstrate that we can apply green chemistry protocols to reduce environmental pollution and disposal of waste toxicants.

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FTIR analysis confirmed the capping of therapeutically potent phytochemicals which are of great use in applied field especially medical.

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Significant Anti-diabetic, Anti-inflammatory, Anti-Alzheimer and Cytotoxic potential of biosynthesized Au-NPs create a new idea and shifting experts to treat cancerous cell lines.

Gold nanoparticles with tiny sizes and biostability are particularly essential and are employed in a variety of biomedical applications. Using a reducing agent and a stabilising agent to make gold nanoparticles has been reported in a number of studies. Gold nanoparticles with a particle size of 25.31 nm were synthesized in this study utilising Hylocereus polyrhizus (Red Pitaya) extract, which functions as a reducing and stabilising agent. The extract of Red Pitaya is said to be a powerful antioxidant and anti-cancer agent. Because of its substantial blood biocompatibility and physiological stability, green production of gold nanoparticles with H. polyrhizus fruit extract is an alternative to chemical synthesis and useful for biological and medical applications. The formation and size distribution of gold nanoparticles were confirmed by HPLC, UV-Vis spectrophotometer, X-ray diffraction (XRD), Dynamic light scattering (DLS), Zeta potential, Transmission electron microscopy (TEM), Fourier transformed infrared spectroscopy (FTIR), Energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS). The well-analysed NPs were used in various biological assays, including anti-diabetic, anti-inflammatory, anti-Alzheimer, and antioxidant (DPPH), and cytotoxic investigations. The NPs also showed a dose-dependent cytotoxic activity against HCT-116, HepG2 and MCF-7 cell lines, with IC₅₀ of 100 µg/mL for HCT-116 cells, 155 µg/mL for HepG2, and for MCF-7 cells the value was 165 µg/mL respectively. Finally, the outstanding biocompatibility of Au-NPs has led to the conclusion that they are a promising choice for various biological applications.

Rowan Berries: A Potential Source for Green Synthesis of Extremely Monodisperse Gold and Silver Nanoparticles and Their Antimicrobial Property

Rowanberries (Sorbus aucuparia) are omnipresent in Europe. The medicinal importance of rowanberries is widely known and corresponds to the active ingredients present in the fruits, mainly polyphenols, carotenoids, and organic acids. In the current study, we explored rowanberries for the reduction of gold and silver salts into nanoparticles. Rowanberries-mediated gold nanoparticles (RB-AuNPs) formed within 5 s at room temperature, and silver nanoparticles (RB-AgNPs) formed in 20 min at 90 °C. The produced nanoparticles were thoroughly characterized by UV-Vis spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray (EDX), transmission electron microscopy (TEM), dynamic light scattering (DLS), single-particle inductively coupled plasma–mass spectrometry (sp-ICP-MS), thermogravimetric analysis (TGA), Fourier transform-infrared spectroscopy (FT-IR) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF). The characterization confirmed that the nanoparticles are highly monodisperse, spherical, stable over long periods, and exhibit a high negative zeta potential values. The produced RB-AuNPs and RB-AgNPs were 90–100 nm and 20–30 nm in size with a thick biological corona layer surrounding them, providing extreme stability but lowering the antimicrobial activity. The antimicrobials study of RB-AgNPs revealed that the nanoparticles have antimicrobial potential with an MBC value of 100 µg/mL against P. aeruginosa and 200 µg/mL against E. coli.

Nanotechnology-Based Delivery Systems for Antimicrobial Peptides

Antimicrobial resistance (AMR) is a significant threat to global health. The conventional antibiotic pool has been depleted, forcing the investigation of novel and alternative antimicrobial strategies. Antimicrobial peptides (AMPs) have shown potential as alternative diagnostic and therapeutic agents in biomedical applications. To date, over 3000 AMPs have been identified, but only a fraction of these have been approved for clinical trials. Their clinical applications are limited to topical application due to their systemic toxicity, susceptibility to protease degradation, short half-life, and rapid renal clearance. To circumvent these challenges and improve AMP’s efficacy, different approaches such as peptide chemical modifications and the development of AMP delivery systems have been employed. Nanomaterials have been shown to improve the activity of antimicrobial drugs by providing support and synergistic effect against pathogenic microbes. This paper describes the role of nanotechnology in the targeted delivery of AMPs, and some of the nano-based delivery strategies for AMPs are discussed with a clear focus on metallic nanoparticle (MNP) formulations.

Advances in Nanotechnology towards Development of Silver Nanoparticle-Based Wound-Healing Agents

Since antiquity, silver-based therapies have been used in wound healing, wound care and management of infections to provide adequate healing. These therapies are associated with certain limitations, such as toxicity, skin discolouration and bacterial resistance, which have limited their use. As a result, new and innovative wound therapies, or strategies to improve the existing therapies, are sought after. Silver nanoparticles (AgNPs) have shown the potential to circumvent the limitations associated with conventional silver-based therapies as described above. AgNPs are effective against a broad spectrum of microorganisms and are less toxic, effective at lower concentrations and produce no skin discolouration. Furthermore, AgNPs can be decorated or coupled with other healing-promoting materials to provide optimum healing. This review details the history and impact of silver-based therapies leading up to AgNPs and AgNP-based nanoformulations in wound healing. It also highlights the properties of AgNPs that aid in wound healing and that make them superior to conventional silver-based wound treatment therapies.