Tabebuia rosea seed extract mediated synthesis of silver nanoparticles with antibacterial, antioxidant, and antiproliferative activities

The green synthesis of silver nanoparticles (AgNPs) using plants has grown in significance recently. The present investigation involved the synthesis of AgNPs utilizing Tabebuia rosea (TR) seeds as a reducing agent. The bioactive potential of the synthesized AgNP was evaluated through antibacterial, antioxidant, and cytotoxicity assays. The confirmation of the formation of AgNPs was achieved through the utilization of UV–vis spectroscopy. The spectroscopic analysis revealed the presence of absorption maxima at 450 nm, which is a distinctive feature of AgNPs. The optimization process for the synthesis of nanoparticles was conducted by varying the pH levels, metal ion (AgNO3), and substrate (Seed extract). The size range of the synthesized nanoparticles was found to be less than 100 nm through the use of scanning electron microscopy (SEM). The profile obtained through energy dispersive x-ray spectroscopy (EDX) analysis of AgNPs exhibited a characteristic optical absorption peak at approximately 3 keV. Further investigation using Fourier transform infrared (FTIR) spectroscopy revealed the involvement of O–H stretching in phenolic compounds and O–H and C=O stretching in carboxylic acids forming AgNPs. The results of the antimicrobial activity assay indicate that the bacteria K. pneumonia exhibited the maximum inhibition zone of 20 ± 0.48 mm, followed by E. faecalis, P. aeruginosa, P. mirabilis, and S. aureus at the highest concentration of 100 mg ml−1, respectively. The DPPH assay findings suggest that the maximum concentration of 500 μg ml−1 of AgNPs exhibited a unique scavenging ability, with a value of 80.98%. Additionally, the application of biologically synthesized AgNPs to treated cells resulted in a cytotoxic effect. The inhibitory concentration (IC50) value of 45  μg ml−1 was determined following a 24 h treatment with human fibroblast cells (L929). Using T. rosea seed to produce AgNPs holds promise for their potential application as nano drugs.


Introduction
Nanotechnology is one of the imperative disciplines of research in the current scenario.Plants and their derivatives are mainly employed in the synthesis of nanoparticles [1].They have excellent mechanical, chemical, and biological properties due to their high surface-to-volume ratio.AgNPs have become significant among the numerous metal nanoparticles created, including platinum, copper, gold, and cadmium, due to their wide applications [2].Various techniques are available to generate AgNPs, including radiation, electrochemistry, photochemistry, and biological processes [3].In the past, scientists have become interested in advanced nanomaterials made of noble metals like silver because of their physicochemical characteristics, including size, dispersion, shape, catalytic activity, and electrical, bioactive, and magnetic properties [4].Drug management has long been a hopeful impression for adopting biological synthesis of nanoparticles in an environmentally responsible way due to the accessibility, large surface area, extensive exposure to the circulatory and lymphatic networks, and the non-invasive nature of the treatment.Researchers are becoming increasingly interested in discovering how secondary metabolites from medicinal plants might be used to cure ailments.However, the time-consuming procedure of isolating the therapeutic component and researching its biological properties is now shorter due to nanotechnology advancements [5].Compared with expensive medications, the green synthesis process of generating metal nanoparticles is simple, environmentally benign, and inexpensive.To create AgNPs, the therapeutic properties of plants are therefore investigated [6].Due to the presence of the chemical lapachol and its derivatives derived from the tree's bark, Tabebuia sp. has a long history of usage as a traditional medicine for cancer treatment [7].Earlier studies on the phytochemical components of Tabebuia rosea leaves found that they contained alkaloids, tannins, phenolic acids, flavonoids, and saponins.The active ingredients in Tabebuia rose's ethanolic leaf extract included 2-furan, carboxaldehyde, and 5-hydroxymethyl [8,9].The leaf extract has been reported to have several effects, including antimicrobial [10,11], cytotoxicity, brine shrimp toxicity, and phytotoxicity on radish seeds [12].TR flowers' cytotoxicity, phytotoxicity, and antioxidant activity have also been documented.The synthesis of AgNPs has thus been investigated as a result of several therapeutic studies on TR leaves [13].Due to its antibacterial quality, silver has historically been used to treat several ailments.Recently, silver has become more widely used in formulations, dressings, gadgets, biosensors, and cancer treatments [14].The goal was to describe and research the anticancer medication created from TR leaf extract.

Collection and preparation of samples
The Tabebuia rosea seed was newly harvested from Bharath Institute of Higher Education and Research, Selaiyur Tambaram, Chennai, Tamil Nādu, India, which is located at latitude 12.8964°north and longitude 80.1435°e ast.Using sterilized scissors, the T. rosea plant seed was cut into small pieces, and then the seed surface was cleaned with sterile distilled water.A 500 ml beaker was used to boil about 50 g of the seed in 300 ml of distilled water for 30 min at 100 °C.After cooling, the extract was filtered using a muslin cloth and Whatman No. 1 filter paper.For later usage, the extract was kept at 4 °C [15].

Biosynthesis of AgNPs
A silver nitrate solution of 0.1 mM was used for the biosynthesis of AgNPs. 1 ml of aqueous seed extract was added to 9 ml of 0.1 mM silver nitrate solution and mixed well under room temperature.The change in colour of the brown solution indicated the reduction of silver ions in the solution.It was monitored periodically by measuring in UV-visible spectroscopy (300 nm to 800 nm) [16].
2.3.Optimization of green synthesis of AgNPs 2.3.1.Different pH 1.0 ml of T. rosea seed aqueous extract and 9.0 ml of 0.1 mM silver nitrate were added, and the mixture was observed for changes in brown color at various pH levels (3, 4, 5, 6, 7, 8, 9,10 and 11) maintained at room temperature.The absorbance of the resulting solutions was determined between 300 and 800 nm using a UV-vis spectrophotometer.

Different concentrations of silver nitrate
To 1.0 ml of T. rosea seed aqueous extract, 9.0 ml of silver nitrate (pH 8.0) at different concentrations 100 mM, 200 mM, 300 mM, 400 mM, and 500 mM was added and incubated at room temperature.The absorbance of the resultant solutions was evaluated using a UV-vis spectrophotometer.

Different concentrations of substrate (Seed extract)
To enhance the production of AgNPs at room temperature., varying quantities of T. rosea seed aqueous extract (0.5 ml, 1 ml, 1.5 ml, 2 ml, and 2.5 ml) were utilized and adjusted to a final volume of 10 ml with 0.1 mM silver nitrate (pH 8.0).The absorbance of the resultant solutions was tested using a UV-vis spectrophotometer within the wavelength range of 300-800 nm.

Synthesis of AgNPs
Using pH, substrate, and silver nitrate concentrations that were all tuned, AgNPs synthesis was accomplished.The solution containing the AgNPs was exposed to several cycles of centrifugation at 12,000 rpm for 30 min after mass manufacturing.The pellet was subjected to the characterisation analysis following Freeze-Drying [17,18].

Characterization of AgNPs
The evaluation of silver ion reduction and the synthesis of AgNPs was conducted by measuring the UV-visible absorbance of the reaction mixture using a UV-vis spectrophotometer, without any dilution.The solution's absorbance and spectra were regularly recorded using a UV spectrophotometer (UV-1800, Genesys 180, Thermo Fisher Scientific, USA) with a resolution between 300 and 800 nm.FTIR spectroscopy was used to determine the functional groups of the synthesised AgNPs.The FTIR spectrum was recognized from 4000-500 cm −1 with a resolution of 16 cm-1 using a Nicolet Summit LITE FTIR spectrometer from Thermo Fisher Scientific, USA, in the attenuated total reflectance sampling (ATR) mode to identify the biomolecules found in the AgNPs made using T. rosea seed extract.SEM images of lyophilized AgNPs applied on copper stubs were studied.XRD (x-ray diffraction) analysis was used to determine the size, structure, and composition of synthesized AgNPs.The determination of size was conducted by measuring the width of the XRD peaks, under the assumption that they exhibit negligible non-uniform stresses using the Scherr formula D 0.94 Cos where D is the average crystallite domain size perpendicular to the reflecting planes, λ is the x-ray wavelength, β is the full width at half maximum (FWHM), and θ is the diffraction angle.The EDX study used secondary electron detectors operating at a 30 kV voltage.The Malvern Zetasizer Nano series, specifically the Nano-ZS90 model, was used to conduct an examination of dynamic light scattering (DLS), zeta potential, and particle size [19].

Biomedical applications 2.6.1. Well Diffusion method
The antibacterial activity of the synthesized AgNPs has been examined using the agar diffusion method.The bacteria (Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumonia, Proteus mirabilis, and Pseudomonas aeruginosa) were subcultured in Muller -Hinton broth medium and subsequently incubated at a temperature of 37 °C for 24 h.The obtained overnight cultures were spread onto Muller -Hinton agar plates to facilitate the growth of a uniform microbial colony.Using sterile cork borer, four evenly spaced wells were produced in the agar plate, each with a 6 mm diameter.Two wells were filled with AgNPs solutions, one containing 50 μl at a concentration of 5 mg ml −1 , and the other containing 100 μl at a concentration of 10 mg ml −1 .The remaining two wells were subjected to filled with 50 μl of Dimethyl sulfoxide (DMSO) as a negative control, while the other was filled with 5 μl of the reference drug tetracycline.Subsequently, the Petri dishes were incubated for 24 h at a temperature of 37 °C.and the zone of inhibition was measured after incubation [19].

Determination of minimum inhibition concentration (MIC)
To determine the MICs, 1 ml of consistent inoculum spores of 1 × 10 7 CFU/ml was mixed with Muller -Hinton Broth (MHB) and consequently added different concentrations of Seed extract from 1.56, 3.125, 6.25, 12.5, 25, 50, 100 μg ml −1 and tetracycline as standard drugs.Then all broths were incubated in aseptic conditions for 12 to 24 h.After 24 h, 0.1 ml of inoculums was withdrawn from each broth concentration and inoculated on Muller -Hinton Broth agar (MHA) to observe MIC.Plates were incubated for 24 h.MIC was the lowest drug concentration that showed less than three colonies or no visible growth on the plates and is considered an inhibition activity of 99% or 100%, respectively [20,21].

Antioxidant activity assay
The antioxidant activity of the aqueous seed extracts of T. rosea and its AgNPs was assessed using the DPPH free radical assay.The evaluation of the DPPH radical scavenging activity was performed following the methodology outlined by Giriwono et al 2020 [22], with some modifications.The aqueous extract of T. rosea and its AgNPs were used in a reaction with the stable DPPH radical in an ethanol-based solution.The experimental solution was generated using different concentrations (25, 50, 100, 200, 300, 400, 500 μ g ml −1 ), 3 ml of 100% ethanol, and 0.3 ml of a 0.5 mM DPPH radical solution dissolved in ethanol.The process of DPPH reduction ensues upon its interaction with an antioxidant compound with the ability to donate hydrogen.The measurement of absorbance (Abs) was conducted at a wavelength of 517 nm after 30 min.Ascorbic acid was used as positive controls.The calculation of scavenging % was performed using the below formula:

MTT assay
The cytotoxicity assessment for AgNPs was conducted through the MTT [3-(4,5-dimethylthiazole-2-yl)−2,5diphenyltetrazolium] assay.The cytotoxic effect of the biosynthesized AgNPs was assessed using the human fibroblast cell line L929.The MTT assay reduces tetrazolium components by viable cells, forming purplecolored formazan crystals.The stock solution of the samples was prepared freshly at 1 mg/1 ml and diluted with cell culture medium to achieve the desired concentrations of 5, 10, 25, 50, and 100 μg ml −1 .The compound was introduced at varying concentrations and subsequently incubated with cells resuspended in phosphate buffer saline (PBS) upon reaching 90% confluency.The negative control in this experiment consisted of cells cultured in a compound-free medium, while the positive control involved treating the cells with Triton X-100 for 48 h.A solution of MTT was prepared by dissolving 5 mg of the substance in 1 ml of PBS and subjecting it to filter sterilization.10 microliters of the MTT solution underwent additional dilution with 90 microliters of serum and phenol red-free medium, resulting in a final volume of 100 microliters.Each well was treated with 100 μl of a solubilisation solution consisting of 10% Triton X-100, 0.1 N HCl, and isopropanol.The mixture was then incubated at room temperature for one h to facilitate the dissolution of formazan crystals.The solution's absorbance was quantified at a wavelength of 570 nm utilizing a Robonik Elisa plate reader Read TOUCH model.Each experiment was subjected to the analysis of three replicate samples.

Statistical analysis
All experiments were performed in triplicate.The data were recorded as mean ± standard deviation from three separate trials

Results and discussion
The synthesis of AgNPs is achieved by reducing silver nitrate to silver ions, facilitated by reducing agents found in the seed extract.This process is evidenced by the change in color from light green to dark brown after 24 h, as depicted in figure 1(a).
The dimensions and morphology of the nanoparticles were analyzed via UV-vis spectroscopy within the wavelength range of 200-800 nm.Uniform-sized AgNPs were optimised using a mixture of 6:4 (S6) silver nitrate and seed extract.This combination was the most effective among the varieties studied, as evidenced by the absorption spectrum of 420 nm, characteristic of surface plasmon resonance for AgNPs.These findings are illustrated in figure 1(a).The reduction of silver nitrate to silver has been attributed to the bioactive molecules found in the seed extract of T. rosea.This can be attributed to various compounds such as saponins, tannins, phenolic acids, flavonoids, and alkaloids [8].Additionally, the functional groups present in the tannins and phenolic compounds of the extract may also contribute to this reduction process.
The standardization and optimization of AgNPs synthesis involved the modification of various pH, metal ion concentrations, and substrate concentrations, which were found to influence the regulation of AgNP shape and size significantly.The particle size is expected to be more prominent in acidic media than in essential media [23].The synthesis of AgNPs at pH 8 resulted in a monodispersed distribution without agglomeration.UV-vis spectroscopy can be used to measure the optical absorption of the nanoparticles.The optical absorption spectrum of a nanoparticle is dependent on its size and shape.A monodispersed distribution of nanoparticles had been confirmed by sharp peak in the optical absorption spectrum.The absorbance peaks confirmed this observed at 420 nm, further supported by the UV-Vis spectrum readings as shown in figure 1(b).Colours ranging from colorless to yellow reflect this pH influence on the size effect [24].Optimal production was observed at a 400 mM metal ion concentration, as indicated by figure 1(c).This statement implies that a significant rise in the concentration of metal ions encourages increased synthesis.Absorption spectra revealed that the optimal substrate concentration of T. rosea seed extract in silver nitrate solution for optimum production of AgNPs was 2.5 ml (figure 1(d)); an increase in the substrate concentration yielded a maximum synthesis.Scanning electron microscopy images of the lyophilized AgNPs showed spherical primary particles of a size below 100 nm, as shown in figure 2(a).The elemental analysis of AgNPs was verified through the use of EDX, as depicted in figure 2(b).
A prominent peak at 3 KeV was detected, a characteristic indication of the absorption of metallic AgNPs.In EDX analysis, the optical absorption peak is reflected by an abrupt increase in the intensity of x-rays emitted by the T. rosea seed extract at the corresponding energy.This is due to the fact that the optical absorption peak corresponds to the light energy that is absorbed most intensely by the sample.When x-rays with this energy strike the sample, they are more likely to discharge electrons from the atoms, resulting in a greater x-ray emission intensity.For instance, AgNPs display a significant optical absorption peak at about 3 keV.This indicates that they absorb light most efficiently at this wavelength.A significant increase in the intensity of the x-rays emitted at 3 keV will be observed when EDX analysis is performed on a sample containing AgNPs.This indicates that AgNPs are present in the sample.The lack of presence of additional constituents serves as a confirmation of the prepared nanoparticles purity.The crystalline nature of AgNPs was confirmed by the XRD pattern depicted in figure 2(c).The diffraction pattern obtained from the sample exhibits four well-defined peaks located at 2θ values of 38.05 θ, 46.23 θ, 62.41 θ, and 72.66 θ.These peaks can be attributed to the reflection planes of the facecentred cubic structure of silver.Supplementary to the Bragg peaks that are indicative of silver nanocrystals, additional peaks were detected at 32.11 θ, 44.98 θ, 56.16 θ, and 61.72 θ and contrasted with the Joint Committee on Powder Diffraction Standards (JCPDS) standard powder diffraction card, silver file No. 04-0783.The emergence of the peaks mentioned above can be attributed to the presence of organic compounds in the seed extract, which facilitated the reduction of silver ions and the stabilization of the resulting nanoparticles [25].The AgNPs are tiny and consistent in size, as shown by their mean hydrodynamic diameter of 12 nm (table 1).The monodisperse grain size distribution supports the well-defined nature of the AgNPs and the absence of substantial aggregates.The AgNPs are stable in solution and won't flocculate or precipitate, owing to the negative zeta potential of −12 mV.These findings show that the synthesized AgNPs are stable in solution and may be kept for extended periods of time without suffering serious deterioration.They are thus a potential material for a range of uses, including imaging, catalysis, and biosensing (table 1).
The functional groups of the synthesised nanoparticles using seed extract of T. rosea were determined with Fourier Transform Infrared (FTIR) spectroscopy.The spectral recordings covered a range of 4000 to 500 cm −1 .After analyzing the spectra, several distinct absorption bands were found, each corresponding to a different functional group.The FTIR spectra of the dye extracted using water (figure 2(d)) showed the O-H stretching alcohol group at 3262 cm −1 followed by N-H stretching amine salt at 2937 cm −1 and 2884 cm −1 .The band at 1709 cm −1 , 1646 cm −1 , and 1516 cm −1 indicate the presence of C=C stretching of cyclic alkanes, and the peak value of 1440 cm −1 , 1399 cm −1 , 1332 cm −1 and 1232 cm −1 reveals strong C-F stretching of fluoro compound.S=O stretching sulfate at 1186 cm −1 , strong C=F stretching at 1146 cm −1 , 1050 cm −1 , 1027 cm −1 and 919 cm −1 followed by unknown compounds at 868 cm −1 , 816 cm −1 and 775 cm −1 consistently.The antimicrobial activity of the synthesized AgNPs was assessed through the diffusion method.The results indicate a noticeable reduction in growth after a 24 h incubation period on plates containing 5 and 10 mg ml −1 of AgNPs, as illustrated in figure 3. The inhibition of bacterial growth near the well can be attributed to the diffusion of inhibitory compounds, specifically AgNPs.A higher zone of inhibition was exhibited by K. pneumonia (20 ± 0.48 mm) followed by E. faecalis (20 ± 0.43 mm), P. aeruginosa (19 ± 0.62 mm), P. mirabilis (18 ± 0.89 mm) S. aureus (16± 0.67 mm) at the maximum concentration (100 mg ml −1 ) (figure 4).The efficacy of AgNPs and leaf extract against the tested pathogens was determined by measuring the minimal inhibitory concentration (MIC).The results indicated that these substances were effective against various microorganisms (table 2).
The ability of AgNPs to traverse the bacterial cell membrane and access the cytoplasm has been shown.Upon entering the cytoplasm, these entities have the capacity to engage with many cellular components, including DNA, proteins, and enzymes, therefore causing disturbances in their normal functionality [26,27].The variability in the constitution of the cellular membrane of microorganisms could potentially elucidate the dissimilarity to those mentioned above.Consequently, a heightened level of structural rigidity ensues, resulting in amplified challenges regarding the infiltration of AgNPs [28][29][30][31].The interaction between AgNPs and the bacterial cell membrane occurs via the binding of AgNPs to the phospholipids, which are negatively charged constituents of the membrane.This binding process leads to the disruption of the bacterial cell membrane.This phenomenon may result in the permeabilization of the bacterial membrane, leading to the extrusion of vital components and subsequent bacterial death [32].The synthesized AgNPs utilize plant phytochemicals, such as terpenoids, flavonoids, phenols, and other phytoconstituents, as a capping agent, significantly contributing to the scavenging of DPPH radicals.The DPPH solution changed from purple to yellow upon exposure to nanoparticles, which is attributed to the acceptance of hydrogen [33].The scavenging ability of the synthesized AgNPs and T. rosea seed extract towards DPPH is comparable to that of the standard ascorbic acid.The results indicate that AgNPs demonstrated the most significant scavenging ability at their maximum concentration of 500 μg ml −1 , with a value of 80.98%.The plant extract and ascorbic acid exhibited scavenging potentials of 73.43% and 92.86%, respectively, at the same concentration (figure 5).
The IC 50 values for the AgNPs and plant extract were determined to be 227.82μg ml −1 and 439.23 μg ml −1 , respectively.The IC 50 value for quercetin was found to be 118 μg ml −1 .AgNPs have the ability to effectively scavenge free radicals, including superoxide anions and hydroxyl radicals.Unstable chemicals known as free radicals have the potential to cause harm to cells and tissues.AgNPs have the potential to mitigate cellular damage by scavenging free radicals [34].The findings of our study align with the previous outcomes on the green synthesis of AgNPs utilizing Lippia nodiflora aerial extract.They observed that the DPPH scavenging capacity increased proportionally to the concentration of the sample.The use of AgNPs has been shown to augment the efficacy of antioxidant enzymes, including superoxide dismutase and catalase.The activity of AgNPs may be enhanced to augment the breakdown of free radicals by enzymes, so providing more cellular protection against harm [35].The study reported that AgNPs demonstrated the most significant scavenging activity of 67% at a concentration of 500 μg ml −1 , while the standard exhibited 83% scavenging activity at the same concentration [36].
Therefore, the cytotoxic effect elicited by AgNPs that were synthesized biologically in the treated cells led to the determination of the inhibitory concentration (IC 50 ) value of 45 μg ml −1 following a 24 h treatment (figure 7).
The study reveals that AgNPs possess the ability to directly impede the activity of mitochondrial dehydrogenase, an enzyme responsible for the reduction of MTT.The inhibition of formazan formation may result in an underestimate of cellular viability [37].In contrast, the AgNPs treated cells exhibited retraction, rounding, detachment from the surface, and suspended cells accumulated.AgNPs have the capability to emit reactive oxygen species (ROS), including superoxide anions and hydrogen peroxide.The impact of ROS on mitochondria, which are responsible for cellular respiration, might result in detrimental effects.Additionally, this phenomenon may impede the generation of formazan, perhaps resulting in an underestimated assessment of cellular viability.The denaturing of proteins, particularly those responsible for the reduction of MTT, may be seen upon exposure to AgNPs.Additionally, this may impede the synthesis of formazan, perhaps resulting in an underestimated assessment of cell viability [38].The findings of this study indicate that the use of AgNPs can lead to the induction of cell death in human fibroblast cells (L929), which is consistent with previous reports [39].

Conclusions
The process of synthesizing AgNPs using T. rosea seed extract was carried out.The change of color in the reaction mixture indicates the synthesis of AgNPs.The AgNPs produced underwent additional characterization through various techniques such as UV-visible spectroscopy, FTIR analysis, SEM, and XRD.The UV-visible spectroscopy analysis of the synthesized AgNPs reveals that their surface plasmon resonance occurs at approximately 450 nm, a distinctive feature of these nanoparticles.The utilization of FTIR spectral studies revealed the existence of diverse functional groups of secondary metabolites that functioned as both reducing and capping agents in synthesizing AgNPs.The utilization of SEM in conjunction with EDX analysis has revealed that the mean diameter of the produced nanoparticles exhibits a consistent spherical morphology with minimal agglomeration.The x-ray diffraction (XRD) analysis validates that the nanoparticles produced possess a crystalline structure of face-centred cubic nature compared to the standard powder diffraction card.The antibacterial activity exhibited a higher zone of inhibition exhibited by K. pneumonia (20 ± 0.48 mm) followed by E. faecalis (20 ± 0.43 mm), P. aeruginosa (19 ± 0.62 mm), P. mirabilis (18 ± 0.89 mm) S. aureus (16± 0.67 mm) at the maximum concentration (100 mg ml −1 ).In addition, an assessment was conducted on the efficacy of green-synthesized AgNPs in scavenging free radicals through various methods, including the DPPH Radical Scavenging Assay; the results were compared to those of the established antioxidant ascorbic acid.The scavenging potential of the AgNPs, seed extract, and the standard was found to be dependent on the dose administered.The AgNPs produced using T. rosea seed extract exhibited a cytotoxicity of up to 95.22% when administered at lower 5 μg ml −1 concentrations.Furthermore, in vivo studies are required to establish the efficacy of this nano drug for use in cancer therapy.

Figure 1 .
Figure 1.UV-vis absorption spectra for the synthesis of AgNPs using the T. rosea seed extract.(a) AgNPs synthesis and colour change, (b) Effect of pH on AgNPs synthesis, (c) Effect of metal ion (AgNO 3 ) on AgNPs synthesis, (d) Effect of the substrate (seed extract) on AgNPs synthesis.

Figure 3 .
Figure 3. Antibacterial activity of the T. rosea seed extract and synthesized AgNPs.

Figure 5 .
Figure 5. Antioxidant activity of the T. rosea seed extract and synthesized AgNPs.

Figure 6 .
Figure 6.Invitro cytotoxicity of the T. rosea seed extract and synthesized AgNPs.

Figure 7 .
Figure 7. MTT assay of the synthesized AgNPs on human fibroblast cell line L929.

Table 1 .
DLS and ELS measurements on the synthesized AgNPs.

Table 2 .
MIC of the T. rosea seed extract and synthesized AgNPs against bacterial pathogens.