Green synthesis of AgNPs from Syzygium aromaticum flower bud extract: arsenic induced stress mitigation with toxicological considerations

Aim: To examine the effect of gold nanoparticles on normal Vero cell lines as well as on three different cancer cell lines (HepG2, HeLa, and MCF7) to evaluate their safety and toxicity. The study aims to assess the biocompatibility and potential cytotoxicity of gold nanoparticles, considering the ongoing debate about their effects on human health. Study Design: Experimental in vitro study. Place and Duration of Study: This study was conducted at P.G. and Research Department of Biotechnology, Marudupandiyar college, Thanjavur Methodology: In this study, Ulva fasciata seaweed was collected from coastal regions of Kerala and Tamil Nadu, cleaned, shade-dried, and powdered for methanolic extraction using Soxhlet apparatus. The resulting extract was used for the phytosynthesis of gold nanoparticles (Au NPs) by reacting with 1 mMH AuCl₄ under dark, static conditions at room temperature. Phytochemical screening identified various bioactive compounds in the extract. Optimization of nanoparticle synthesis was carried out by varying pH, temperature, extract and metal salt concentrations, and incubation time, with stability assessed over 12 months. The Au NPs were characterized using techniques such as UV–vis spectroscopy, HRTEM, EDX, XRD, DLS, zeta potential, AFM, and ICP-OES. Cytotoxic effects of the Au NPs were evaluated via MTT assay against normal (Vero) and cancer (HepG2, HeLa, MCF7) cell lines to determine IC50 values, and apoptosis in HepG2 cells was confirmed using PI and AO/EB staining under fluorescence microscopy. Results: Phytosynthesized gold nanoparticles (Au NPs) using Ulva fasciata extract exhibited a characteristic UV-Vis absorbance peak at 545 nm, confirming their formation. Phytochemical analysis of the extract revealed the presence of various bioactive compounds such as alkaloids, phenolics, flavonoids, and terpenoids, which likely mediated the nanoparticle synthesis. Optimal synthesis conditions were determined as pH 7, 1.0 mM HAuCl₄, 1.0 mL extract, 37°C, and 24-hour incubation. Characterization revealed predominantly spherical, crystalline Au NPs with a size range of 25–35 nm by HR-TEM, a maximum hydrodynamic diameter of 50 nm (DLS), and a zeta potential of -16.0 mV, indicating good stability. XRD confirmed face-centered cubic structures, and EDX and SAED affirmed elemental purity and crystallinity. AFM showed smooth, spherical particles (~60–90 nm), and ICP-OES quantified Au NP concentration at 258.0 mg/L. In vitro cytotoxicity tests demonstrated higher biocompatibility of Au NPs (IC₅₀: 75µg/mL) compared to gold chloride (IC₅₀: 10µg/mL) in Vero cells. Au NPs showed dose-dependent anticancer activity, with IC₅₀ values of 30µg/mL (HepG2) and 50µg/mL (HeLa and MCF7). Fluorescent staining of HepG2 cells revealed apoptotic features, including chromatin condensation and nuclear fragmentation, confirming the pro-apoptotic effects of the Au NPs. Conclusion: Gold nanoparticles show promise as a non-toxic drug delivery vehicle in normal cells while exhibiting cytotoxic effects in cancer cell lines. These findings suggest potential for selective therapeutic applications, though further studies are needed to confirm long-term safety and efficacy.

Introduction: The biosynthesis of gold nanoparticles (AuNPs) is a rapidly developing field that integrates biological systems with nanotechnology to produce nanoparticles with unique properties. This study aimed to biosynthesize gold nanoparticles using Asparagus Racemosus root extract (popularly known as Shatavari root aqueous extract) (AR-AuNPs), to characterize the AuNPs spectrally, and to explore their potential applications. Methods: AuNPs were synthesized using Shatavari extract, leveraging its polyphenolic content for the reduction of gold ions. The formation of nanoparticles was confirmed using UV-Vis spectroscopy, with a surface plasmon resonance peak at 550 nm. Further characterization was performed using electron microscopy to assess size and morphology, X-Ray Diffraction (XRD) to analyse the crystalline structure, Fourier-Transform Infrared Spectroscopy (FTIR) to identify functional groups, and Dynamic Light Scattering (DLS) to determine particle size and zeta potential. Results: The bio-synthesized gold nanoparticles are spectrally characterized; the size of the gold nanoparticles is below 50 nm, and they reveal very good biomedical applications. The biosynthesized AR-AuNPs exhibited strong antioxidant activity, with the nitric oxide (NO) scavenging method proving superior to the DPPH and H2O2 assays. While the antimicrobial activity of ARAuNPs was limited against both Gram-positive and Gram-negative bacteria, they showed effective DNA binding activity. Discussion: The synthesized gold nanoparticles exhibited a characteristic UV-Vis absorption peak at 550 nm, confirming their successful formation. Dynamic Light Scattering (DLS) analysis revealed an average particle size of 44.7 nm, and the zeta potential was measured at -14.3 mV, indicating moderate stability. The polyphenols present in the aqueous extract of Shatavari plant roots likely played a role in both the reduction and stabilization of the AuNPs. When tested on A549 cell lines, the AR-AuNPs demonstrated significant antiproliferative activity, with an IC50 value of 68.99 μM, compared to Cisplatin. However, they lacked anticancer activity against MCF-7 cell lines. The biosynthesized AR-AuNPs exhibited strong antioxidant activity, moderate antimicrobial activity, and effective DNA binding activity. Conclusion: Biosynthesizing AuNPs using Shatavari extract is a green, sustainable method that produces nanoparticles with desirable properties for various applications. The synthesized AuNPs exhibit promising capabilities in the fields of medicine and environmental science, positioning them as valuable tools for future research. Further studies are needed to explore their potential in real-world applications.

Green synthesis emerged as an effective approach for the eco-friendly synthesis of nanoparticles with improved biological applications. This study assesses the potential of root extract of Swertia cordata for the green synthesis of silver nanoparticles and examines their antimicrobial and antioxidant properties. Different analytical techniques such as UV-visible spectroscopy, Zeta potential, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM) analysis, were employed to characterize silver nanoparticles. The formation of silver nanoparticles was initially verified using UV-visible spectroscopy, which exhibited a characteristic absorption peak at 454 nm. XRD analysis revealed the face-centered cubic (FCC) crystalline structure. The zeta potential of −35 mV indicated the highest colloidal stability due to repulsion between the particles. The DLS confirms that the particle size distribution was between 80 and 120 nm. EDX analysis detected silver as the highest amount in the sample. The biosynthesized silver nanoparticles exhibit remarkable antibacterial activity against both Gram-negative bacteria and Gram-positive bacteria. The largest zone of inhibition was observed against Streptococcus pneumoniae (29 ± 1.5 mm) at a dose of 0.9 mg/mL. The synthesized silver nanoparticles also showed efficient and strong antifungal activity against two fungal strains, viz., Penicillium nutatum and Rhizopus stolonifera. The free radical scavenging activity of the synthesized silver nanoparticles was highest (69.5%) at 50 ppm of AgNPs concentration. The results confirm that silver nanoparticles synthesized from S. cordata root extract exhibited remarkable antimicrobial and antioxidant potential, making it therapeutic alternative for treating several diseases.

From time immemorial herbal preparations are been employed for the treatment of several ailments. In recent years due to poor bioavailability the conventional herbal preparations are replaced by phytoniosomes, an advanced novel drug delivery system in which the herbal extracts are incorporated into a non-ionic surfactant to yield higher absorption and remarkable desired pharmacological activity. The present study is aimed to prepare and characterize the ethanolic leaf extract of Tinospora cordifolia (nELETC) loaded phytoniosome and to compare its antioxidant properties with ethanolic leaf extract of Tinospora cordifolia (ELETC). The ethanolic leaf extract and ethanolic leaf extract of Tinospora cordifolia loaded phytoniosome (ELETC and nELETC) were prepared. The characterization of the prepared phytoniosomes were performed by UV-Visible spectroscopy, FTIR, XRD, SEM, TEM, DLS and zeta potential. The nontoxic nature of the prepared phytoniosomes was analyzed using MTT assay in vero cell line. The antioxidant potential of ELETC and nELETC were compared by the scavenging activity of DPPH, Hydrogen peroxide and Superoxide radicals. The formation of ethanolic leaf extract of Tinospora cordifolia loaded phytoniosome (nELETC) was confirmed with UV-Vis spectroscopy. The SEM and TEM images confirmed the spherical shape of the nELETC with average size ranging from 600 to 1800 nm. The zeta potential showed magnitude of -65.55 to -77.83 mV and its crystalline structure was confirmed by XRD analysis. Through the FTIR spectrum presence of alcohols, alkanes, phenols, esters, aliphatic and aromatic compounds as well as alkenes and carbolic acids were identified. MTT assay establishes the non-toxic nature of the synthesized nELETC and excellent antioxidant potential was observed for nELETC than ELETC. In conclusion, the ethanolic leaf extract of Tinospora cordifolia loaded phytoniosome (nELETC) will serve as a promising drug carrier in scavenging the free radicals and can be used in various biological applications.

This research focuses on the plant-mediated green synthesis process to produce gold nanoparticles (Au NPs) using upland cress (Barbarea verna), as various biomolecules within the upland cress act as both reducing and capping agents. The synthesized gold nanoparticles were thoroughly characterized using UV-vis spectroscopy, surface charge (zeta potential) analysis, scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX), atomic force microscopy (AFM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray diffraction (XRD). The results indicated the synthesized Au NPs are spherical and well-dispersed with an average diameter ~11 nm and a characteristic absorbance peak at ~529 nm. EDX results showed an 11.13% gold content. Colloidal Au NP stability was confirmed with a zeta potential (ζ) value of −36.8 mV. X-ray diffraction analysis verified the production of crystalline face-centered cubic gold. Moreover, the antimicrobial activity of the Au NPs was evaluated using Gram-negative Escherichia coli and Gram-positive Bacillus megaterium. Results demonstrated concentration-dependent antimicrobial properties. Lastly, applications of the Au NPs in catalysis and biomedicine were evaluated. The catalytic activity of Au NPs was demonstrated through the conversion of 4-nitrophenol to 4-aminophenol which followed first-order kinetics. Cellular uptake and cytotoxicity were evaluated using both BMSCs (stem) and HeLa (cancer) cells and the results were cell type dependent. The synthesized Au NPs show great potential for various applications such as catalysis, pharmaceutics, and biomedicine.

Conventional agriculture on chemical fertilizers and pesticides has serious environmental and health implications. This necessitates the development of more sustainable and eco-friendly alternatives. This study aimed to synthesize zinc oxide nanoparticles (ZnONPs) using Cassia absus leaf extract via a green synthesis approach and evaluate their dual role as biofertilizers and biopesticides in sustainable agriculture. The biosynthesized ZnONPs were characterized using UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), dynamic light scattering (DLS), and zeta potential analysis. A characteristic absorption peak at 355nm confirmed nanoparticle (NP) formation, whereas XRD analysis revealed a hexagonal wurtzite structure with a crystallite size of 45-55nm. SEM analysis showed spherical to quasi-spherical NPs with an average size of 75nm, whereas DLS indicated a hydrodynamic diameter of 83.5nm and a zeta potential of + 48.7 mV, confirming excellent colloidal stability. The in vitro antibacterial activity of ZnONPs was evaluated against the phytopathogens Ralstonia solanacearum, Xanthomonas euvesicatoria, and Clavibacter michiganensis subsp. michiganensis. Significant inhibition zones of 20mm, 18mm, and 27.5mm, respectively, were observed, with minimum inhibitory concentrations (MICs) of 30, 40, and 20µg/mL. In pot experiments using Capsicum annuum, ZnONPs significantly enhanced plant growth parameters, including plant height, leaf length, and leaf width, with up to a 37% improvement observed at moderate concentrations (5µg/10 mL). These results demonstrate that ZnONPs offer an effective dual strategy for enhancing plant growth and controlling bacterial pathogens, making them promising candidates for sustainable agricultural applications.

Toxoplasma gondii is a zoonotic intracellular protozoan with worldwide distribution. Acute and severe toxoplasmosis are commonly reported in patients who suffer from acquired/congenital immune deficiency. This study aimed to synthesize mannosylated paromomycin-loaded solid lipid nanoparticles (PM-SLN-M) and to evaluate them on acute toxoplasmosis. SLN was synthesized and then loaded by 7 mg/mL paromomycin sodium. Mannose coating was performed, and after washing, the size, zeta potential, and loading percentage were calculated. To evaluate the cell toxicity, an MTT assay was performed on Vero cells by different concentrations (log 10−1) of SLN, PM-SLN-M, and PM-SLN. In addition, the anti-Toxoplasma effects were also evaluated using trypan-blue staining and scanning electron microscopy (SEM). An MTT assay was also employed to evaluate the effects of PM and PM-SLN-M on intracellular Toxoplasma. A 6-month stability test of PM-SLN and PM-SLN-M represented that the characteristics all remained constant. The cell viability assay demonstrated that PM-SLN-M had lower cell toxicity (<20%) compared to PM-SLN (<30%) and PM (<40%). Statistical analysis showed that PM-SLN-M significantly killed ~97.555 ± 0.629 (95% CI: 91.901 to 103.209; P < 0.05) of T. gondii tachyzoites. More than 50% of Toxoplasma-infected Vero cells remained viable in concentrations more than 0.07 μg/mL and 7 μg/mL of PM and PM-SLN-M, respectively. SEM analysis showed that T. gondii tachyzoites were changed in both size and morphology facing with PM-SLN-M. Our findings indicated that synthesized PM-SLN-M had anti-Toxoplasma activity without significant host cell toxicity at the highest concentration. Our study demonstrated that PM was able to kill intracellular Toxoplasma in lower concentration in comparison to PM-SLN-M, although PM-SLN-M showed lower cytotoxic effects on Vero cells.

The increase in antimicrobial resistance necessitates the development of new therapeutics. In this context, silver nanoparticles (AgNPs) show considerable promise due to their multiple antimicrobial mechanisms, including cell wall disruption, oxidative stress, and DNA damage, as well as their relatively low toxicity. The effectiveness of AgNPs depends on their size, shape, and surface modifications; their combination with ligands can also produce synergistic effects. In this study, cloxacillin sodium (a β-lactam antibiotic) was employed as a ligand to synthesize Clox@AgNPs under UV (311 nm) irradiation using a photo-reduction method. The characteristic absorbance peak, morphology, surface charge, and diameter of the Clox@AgNPs were analyzed using UV–visible spectroscopy, scanning transmission electron microscopy, fourier-transform infrared spectroscopy, dynamic light scattering and zeta potential analyses. The antibacterial activity of the Clox@AgNPs against methicillin-resistant Staphylococcus aureus (MRSA) was then evaluated to enhance the efficacy of existing antibiotics. This approach may provide a valuable contribution to future antimicrobial strategies.

Bacterial leaf blight (BLB) of rice is caused by the bacterium Xanthomonas oryzae pv. oryzae (Xoo) and leads to significant yield loss. The overuse of antibacterial chemicals casuse environmental toxicity, high cost, and low biosafety generating interest in eco-friendly alternatives.This study evaluated the antibacterial efficacy of biosynthesized zinc-chitosan nanoparticles (ZnChNPs) against Xanthomonas oryzae pv. oryzae (Xoo). Successful synthesis was confirmed by UV-visible spectroscopy with a characteristic absorption peak at 356 nm. Comprehensive physicochemical characterization using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FESEM) revealed ZnChNPs with diverse polymorphic morphologies, while energy dispersive spectroscopy (EDS) confirmed zinc, oxygen, and carbon as the major elemental components. Fourier transform infrared spectroscopy (FTIR) analysis identified key functional groups associated with nanoparticle formation and stabilization, and X-ray diffraction (XRD) patterns verified a crystalline hexagonal wurtzite structure. Dynamic light scattering (DLS) measurements showed a mean hydrodynamic diameter of 256.2 nm, and a zeta potential of -25.1 mV indicated good colloidal stability of the formulation. In vitro, ZnChNPs:dH₂O at 8:2 and 10:0 ratios showed inhibition zones of 22.75 mm and 24.84 mm, respectively. In net house conditions, treatments reduced BLB lesion lengths by 36%-73.54% at 14 days and 34.98%-63.66% at 21 days. The Bismerthiazol (0.15%) + ZnChNP:dH₂O (8:2) treatment reduced lesions by 68.28% and 55.48% at 14 and 21 days, respectively. Field trial results showed 66.14% and 61.27% reductions at 14 and 21 days. These findings suggest ZnChNPs can be used as a sustainable strategy for controlling BLB in rice in an effective manner.

Comparative study between Phragmites australis root and rhizome extracts for mediating gold nanoparticles synthesis and their medical and environmental applications

This study adopted a green synthesis method to produce silver nanoparticles (Ag NPs) using arabinoxylan mucilage from Plantago major seeds, which naturally functions as a reducing and stabilizing agent. Different characterization techniques like UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy dispersive X-rays (EDX), and X-ray diffraction (XRD) were used to determine the morphology, composition, and surface functionality of the synthesized nanoparticles. The formation of Ag NPs was indicated by a color change from light brown to dark brown and a characteristic absorption peak at 420 nm, with increased absorption over time due to the enhanced production of NPs. FTIR analysis confirmed Ag NP formation with characteristic bands in the 400–600 cm⁻¹ range. SEM analysis revealed flower-shaped Ag NPs, while XRD confirmed the face-centered cubic crystalline structure. Dynamic light scattering (DLS) analysis showed stable Ag NPs with a slightly negative surface charge (-0.1 mV). The synthesized Ag NPs exhibited effective antimicrobial activity against Escherichia coli, Enterobacter aerogenes, and Bacillus cereus, demonstrating superior inhibition zones, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) values compared with the positive control, rifampicin. Additionally, Ag NPs demonstrated significant photocatalytic potential in water purification, degrading crystal violet (87.12%) and safranin dye (83.87%) following pseudo-first-order kinetics. The findings highlight the potential of Ag NPs as eco-friendly alternatives to synthetic wastewater treatment agents and antibiotics.

This contribution reports on the comparative synthesis and the main physical properties of ZnO NPs using green and chemical methods. A green approach was applied for synthesis of zinc oxide NPs for the first time using Nerium oleander flower extract as capping and reducing agent (ZnO–G). The chemical method was applied using sodium borohydride as reducing agent (ZnO–C). The green chemistry plant-based ZnO NPs are safer, energy efficient, eco-friendly, and less toxic than chemically synthesized counterparts. The characterization of ZnO–G and ZnO–C NPs was ascertained through Fourier Transform-Infrared (FT-IR), UV–Vis spectroscopy, X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), Thermal gravimetric and differential thermal analysis (TG–DTA). From the FT-IR spectra of ZnO NPs, the characteristic absorption peak of Zn–O bond was observed at 478 and 466 cm−1 for ZnO–G and ZnO–C respectively. The shifted of Zn–O band due to the difference of bio-functional groups of N. oleander extract. Formation of nanoparticles was monitored using UV–Vis spectroscopy and a characteristic absorption peak for ZnO–G and ZnO–C was observed at 271 and 323 nm respectively. The XRD result for the ZnO shows the tendency of the three most intense diffraction peaks with crystalline structure of ZnO–C more than ZnO–G. The average crystallite size of ZnO–G and ZnO–C at scattering angle (2θ) 23.96 and 33.10 was 37.10 and 27.03 nm respectively. The EDX gave strong signals for zinc and oxygen indicating the occurrence of the nanoparticles in their oxide form rather than the pure zinc form. The SEM image shows the surface morphology of ZnO–G and ZnO–C displays a drastic modification of the surface morphology with the change of the synthesis method. Kinetic analyses of the ZnO thermal decomposition was calculated using Broido equation. This new eco-friendly synthesis of ZnONPs is a convenient technique for large scale commercial manufacture of ZnO NPs.

Objective To investigate the effects of sodium arsenite (NaAsO2) on cell survival circumstance, reactive oxygen species (ROS) and cell apoptosis in human normal hepatic cells (L-02). Methods L-02 cells were exposed to different doses of NaAsO2 (0, 50, 100, 150 μmol/L) for 24 h. MTT assay was used to detect the survival of L-02 cells, and flow cytometry (FCM) was used to detect the ROS levels and the early (Q4), late (Q2) apoptosis of L-02 cells. Results Cell survival rate: cell survival rate was compared between groups, the difference was statistically significant (F= 350.51, P < 0.05), the cell survival rates of 50, 100 and 150 μmol/L NaAsO2 groups [(87.30 ± 3.74)%, (49.03 ± 4.72)%, (13.44 ± 4.01)%] were significantly lower than that of the control group [(100.00 ± 0.00)%, all P < 0.05]; compared with 50 μmol/L NaAsO2 group, the cell survival rates of 100 and 150 μmol/L NaAsO2 groups were significantly decreased (all P < 0.05); compared with 100 μmol/L NaAsO2 group, the cell survival rate of 150 μmol/L NaAsO2 group was significantly decreased (P < 0.05). The ROS levels: ROS levels were compared between groups, the difference was statistically significant (F= 407.78, P < 0.05), the ROS levels of 100 and 150 μmol/L NaAsO2 groups (3 212.00 ± 221.93, 5 521.33 ± 179.63) were significantly higher than that of the control group (1 691.67 ± 73.98, all P < 0.05); compared with 50 μmol/L NaAsO2 group (1 927.67 ± 62.45), the ROS levels of 100 and 150 μmol/L NaAsO2 groups were significantly increased (all P < 0.05); compared with 100 μmol/L NaAsO2 group, the ROS level of 150 μmol/L NaAsO2 group was significantly increased (P < 0.05). Cell apoptosis: cell apoptosis rates of Q2, Q4 and Q2+ Q4 were compared between groups, the differences were statistically significant (F= 256.84, 26.53, 63.89, all P < 0.05); excecpt the cell apoptosis rate of Q4 in 50 μmol/L NaAsO2 group [(5.43 ± 0.57)%], the cell apoptosis rates of Q2 [(5.67 ± 0.21)%] and Q2+ Q4 [(11.10 ± 0.40)%] in 50 μmol/L NaAsO2 group, the cell apoptosis rates of Q2 [(13.60 ± 0.79)%], Q4 [(7.37 ± 2.01)%] and Q2+ Q4 [(20.97 ± 2.38)%] in 100 μmol/L NaAsO2 group, the cell apoptosis rate of Q2 [(13.47 ± 0.78)%], Q4 [(16.97 ± 3.45)%] and Q2+ Q4 [(30.43 ± 3.84)%] in 150 μmol/L NaAsO2 group were significantly higher than those of the control group [Q2: (3.47 ± 0.12)%, Q4: (2.90 ± 0.90)%, Q2+ Q4: (6.37 ± 1.00)%, all P < 0.05]; compared with 50 μmol/L NaAsO2 group, the cell apoptosis rates of Q2, Q4 and Q2+ Q4 in 100 and 150 μmol/L NaAsO2 groups were increased, except the cell apoptosis rate of Q4 in 100 μmol/L NaAsO2 group, the differences were statistically significant (all P < 0.05); the cell apoptosis rates of Q4 and Q2+ Q4 in 150 μmol/L NaAsO2 group compared with 100 μmol/L NaAsO2 group were significantly increased (all P < 0.05). Conclusions NaAsO2 can induce L-02 cells to increase ROS levels, and inhibit L-02 cell proliferation. In addition, NaAsO2 can induce early apoptosis and late apoptosis in L-02 cells. Key words: Arsenites; L-02 cells; Reactive oxygen species; Cell apoptosis

Effects of biogenic synthesis of chitosan entrapped silver nanoparticle from Aegle marmelos on human cervical cancer cells (HeLa)

Green nanoparticle synthesis has emerged as a sustainable and environmentally benign approach for the production of metal and metal oxide nanoparticles. Unlike conventional physical and chemical methods that involve toxic reagents, high energy consumption, and hazardous byproducts, green synthesis utilizes biological resources such as plant extracts, microorganisms, and biomolecules as reducing and stabilizing agents. Plant-mediated synthesis is particularly advantageous due to its simplicity, cost-effectiveness, scalability, and rapid reaction kinetics. Phytochemicals including flavonoids, phenolics, alkaloids, proteins, and carbohydrates play a crucial role in the reduction of metal ions and stabilization of the formed nanoparticles through functional groups such as hydroxyl, carbonyl, and amine groups. The integration of green chemistry principles with nanotechnology not only minimizes environmental impact but also promotes the development of sustainable materials for industrial applications. The present study reports the green synthesis and biological applications of zinc nanoparticles (ZnNPs) using Terminalia arjuna leaf extract. The synthesized ZnNPs were characterized using UV–Visible spectroscopy and FTIR analyses to confirm their formation, functional groups involvement, crystalline nature, and surface morphology. The UV–Vis spectra showed a characteristic absorption peak confirming nanoparticle formation, while FTIR analysis indicated the participation of bioactive functional groups in reduction and stabilization. Antioxidant assay of the synthesized zinc nanoparticle showed 65% of inhibition at 10 μL concentration. Antibacterial activity of the green nanoparticle showed greater zone of inhibition against both Gram –- positive and Gram-negative bacterial strains. The synthesized green zinc oxide nanoparticles offer safer and sustainable alternatives for biomedical applications. Keywords: Green nanoparticle, Metal oxide, Phytochemicals, Sustainable materials