1 Introduction

Nanotechnology represents use of a tiny molecule with a unique size ranged from 1 to 100 nm [1,2,3,4]. Nowadays, nanotechnology is interfered in several applications as biological, pharmaceutical, photocatalysts, information technology, electrocatalysts, chemical science, physics, wastewater treatment, infection control, and cotton textiles [5,6,7,8,9,10,11,12,13,14]. Additionally, biotechnological applications, particularly those related to antibacterial, anticancer, biocompatibility, and anti-inflammatory properties, are growing. Three methodologies are available for generating nanoparticles [15,16,17,18,19,20,21]. Chemical, physical, and biological however the most recommended is green synthesize due to a lot of reasons as good defined size, clean, ecofriendly, cost-effective, safe, and shape nanoparticles synthesized [22,23,24,25,26,27,28,29,30,31]. The biological production of nanoparticles involves several types of living creatures, including plants, fungi, algae, bacteria, and viruses [32, 33]. However, fungi have more advantages due to fungal metabolites contain large number of proteins and enzymes which are highly effective in fabrication of nanoparticles, easily in downstream handling and scaling up, tolerance to metallic materials, economic facility, and production of huge biomass by several species of fungi [34,35,36,37]. There are many fungi has affinity to synthesize AgNPs and AuNPs extracellularly such as Trichoderma saturnisporum, Phanerochaete chrysosporium, Fusarium oxysporum, Coriolus versicolor, and Pleurotus sajorcaju [38,39,40,41]. Helminthosporium tetramera, Penicillium fellutanum, Schizophyllum radiatum, and Fusarium keratoplasticum were rapidly produced silver nanoparticles [42,43,44,45,46]. Also, nano-sized gold particles produced by different species of Fusarium oxysporum and Penicillium aurantiogriseumm [47, 48]. In addition to, Aspergillus sydowii has ability to synthesize AuNPs from action of cell-free filtrate within a minute [49]. The most main problem that has a negative impact to the medical field is the infectious diseases that lead to the death of many people worldwide [50]. Nowadays, increasing resistance of microbes to traditional drugs is due to using antibiotics without lacking to the patients and generations of microorganisms with a development of virulence factors of pathogenic [51, 52]. Also, Au-NPs and Ag-NPs are highly displayed antibacterial properties for causative disease of Gram-negative bacteria as Shigella dysenteriae, Pseudomonas aeruginosa, Enterobacter aerogenes, Klebsiella pneumonia, Salmonella typhimurium, Proteus mirabilis, and, E. coli. Along with, Gram-positive pathogenic bacteria include Enterococcus faecalis, Staphylococcus epidermidis, Bacillus subtilis, Staphylococcus aureus, and Streptococcus pyogenes [53,54,55,56,57]. Moreover, bacteria have been developed additional strategies, including biofilm formation, to evade the actions of many inhibitors. Biofilms are abiotic or biotic substances which are a community of living microorganisms that establish a strong connection between them and the surface that are connected [58, 59]. This connection is mediated by substances secreted by microorganisms present in the biofilm [60, 61]. Additionally, the presence of biofilm matrix around the bacterial cells is the other reason to resistance of bacteria to well-known antimicrobial agents. So, non-traditional antibiotics have a great interest by many researchers to in resolve this challenge by production of novel nano antibiotics compound which can be overcoming resistant of pathogenic microorganisms [62, 63]. Furthermore, medical transplantation has a bad effect due to presence of bacterial, so sterilization and uses of materials have antibiofilm activity are some ways to limit formation of biofilm [64]. Furthermore, the common components interfere in the composition of biofilm are extracellular polymeric molecules as proteins, polysaccharides, and extracellular DNA [65]. Additionally, bacterial biofilms indicate a possible alteration in its structure and function when exposed to biomolecules [58]. Obviously, development of a novel compounds has ability to destroy and prevent bacterial biofilm through a recent mode of action is the resolving of these problems [66,67,68]. Cancer seems to be nowadays the second major incidence of dying in developed nations, giving it a severe health issue. It is a multi-step process that is defined by aberrant cell proliferation and is brought on by alterations in the genetic makeup and modified by environmental variables [69]. There are many different cancer medicines in use today, and significant improvements are continually being studied. Nanotechnology has just come to light as a reasonable alternative for a number of challenges, and it has been thought to bring about a fundamental alteration in the identification, management, and therapy of malignancy [70].

In the current work, AgNPs and AuNPs were mycosynthiezed using Fusarium pseudonygamai, as well as their nanostructures were characterized by several analyses. Moreover, this study aimed to assess mycosynthesized AuNPs and AuNPs in various biomedical applications including antimicrobial, antibiofilm, anticancer, and antioxidant efficacies.

2 Materials and methods

2.1 Materials

Silver nitrate (AgNO3) and chloroauric acid (HAuCl4) were purchased from Sigma-Aldrich, USA, for chemicals and used as precursors for preparation Ag-NPs and Au-NPs. Other chemicals, culture media, and reagents used in this study were purchased from Modern Lab Co., India, in analytical grade without any purification required.

2.2 Isolation and identification of fungal isolates

From several agricultural soil sites in Qalyub, Egypt, 15 soil samples have been taken. After successive dilutions of the soil samples, the inoculum was plated on potato dextrose agar (PDA) and incubated at 28 ± 2 °C for 3–4 days to isolate the fungi. Chloramphenicol (10 µg/mL) added to the medium after autoclaving assisted in preventing bacterial contamination. Purity of the fungal growth was evaluated, and the isolated fungus was injected in the cultural slant for conservation at 4 °C for additional investigation. Molecular identification using genomic DNA as well as its region amplification, first most efficient fungal strain, was genetically identified. For the ITS-based sequencing, 0.1 g of fungal mycelium genomic DNA was extracted. The Gene Jet Plant genomic DNA purification Kit (Thermo) #k0791 procedure has been used to extract the DNA. ITS1 and ITS4 have been the primers employed. The Maxima Hot Start PCR Master Mix (Thermo) #k0221 by Sigma Scientific Services Company (Cairo, Egypt) was used in the following amplification (PCR) procedure: Thermo’s Maxima Hot Start PCR Master Mix, 0.5 µM from each primer, as well as 1 µL of isolated fungal genomic DNA, were all added to a 50 µL PCR mixture. In a DNA Engine Thermal Cycler, the PCR was carried out with a hot start at 94 °C for 3 min, followed by 30 cycles of 94 °C for 30 s, 55 °C for 30 s, and 72 °C for approximately 60 s, then a further 10 min at 74 °C of extension. Using forward and reverse primers and an ABI 3730 1 DNA sequencer, the specimens subsequently processed by GATC Company (Germany).

2.3 Screening of biosynthesis AgNPs and AuNPs using fungal isolates

On an orbital shaker, 1 mM of silver nitrate (AgNO3) was combined with cell-free filtrate and incubated at 28 ± 2 °C for 24 h (120 rpm). After the incubation period was through, the color change could be seen for up to 72 h. After that, the samples were separated and dried at 150 °C for 48 h. Eventually, the bio-transformed product was collected and submitted for more investigation. The same procedures for chloroauric acid (HAuCl4) were used to create gold nanoparticles instead of silver nitrate.

2.4 Biosynthesize of AgNPs and AuNPs by fungal isolate TB-13c

Fungal isolate TB-13c was cultivated for three days at pH 6.0, 28 ± 2 °C, and 140 rpm shaking inside a 250-mL flask that contain 100 mL of Czapek Dox (CD) broth medium. Then, fungal biomass subsequently was filtered and rinsed repeatedly by sterile D H2O water to eliminate any medium constituents. The resulting suspension of the fungal biomass in sterile distilled water (1:10) was then agitated for couple of days at 28 °C at 150 rpm, whilst also collecting the fungal biomass using filter paper. The synthesis of AgNPs and AuNPs utilized the cell-free filtrate in the manner described below. Before incubating with cell-free filtrate at 28 ± 2 °C for 72 h on an orbital shaker (150 rpm) in the dark, 1 mM of AgNO3 and HAuCl4 were combined, and the pH was then adjusted at 10 for AgNPs and 5 for AuNPs. Following the incubation time, AgNPs and AuNPs showed a brown and violet colors, respectively. The latter was separated and dried for 48 h at 150 °C. Eventually, the bio-transformed product was gathered and submitted for more research.

2.5 Characterization of AgNPs and AuNPs

AgNP and AuNP biosynthesis were detected using to detect an intense absorption peak associated with surface plasmon excitation, to acquire the optical UV–Vis absorption properties, use the JASCO 730 double beam spectrophotometer at wavelengths 200–700 nm. AgNPs and AuNPs that were synthesized from biological materials were measured using a transmission electronic microscope (TEM) (JEOL-2100). In order to achieve this, standard copper grids being given a drop of NP-containing solution to apply, which was followed by a full night of vacuum drying before the grids were put into a specimen container. Additionally, using Fourier transform infrared (FTIR) spectroscopy (JASCO, FT/IR- 6100), several functional groups found in biofabricated NPs molecules were examined. AgNP and AuNP samples were blended with KBr before being crushed firmly into discs. To get FTIR spectra, these discs were scanned between 400 and 4000 cm−1. The morphological properties and constituent structures of mycosynthesized AgNPs and AuNPs were examined using SEM coupled to a JEOL JSM-6510 LV energy-dispersive spectroscope (EDS) instrument. The crystal structures of silver and gold NPs were described by XRD analysis (XRD, X PERT PRO-PAN Analytical).

2.6 Antimicrobial activity

The MIC values of two different substances (AgNPs and AuNPs) were examined against a multidrug resistant strains (MRSA, MSSA, P. aeruginosa, and K. pneumonia) using the broth microdilution technique. AgNPs and AuNPs were prepared at various concentrations (1000, 500, 250, 125, 62.5, 31.25, and 15.75 μg/mL). Test samples (100 μL) of various concentrations were added to 100 μL of double-strength Mueller Hinton (MH) broth-filled sterile microtiter plate wells. In all wells save the negative control one, bacterial cell suspension (20 μL) corresponding to (OD comparable to 0.5 McFarland standard) was administered. To test whether MH broth could adequately support bacterial growth, bacterial solution was added to positive control wells. The MH broth and sterile distilled water used in the negative control wells were used to ensure sterility. The plates were incubated for 24 h at 37 °C. After that, the plate subsequently re-incubated again for 6 h with 30 µL of resazurin solution (0.02 percent wt/v) (HiMedia) added to each well to detect bacterial growth. Bacterial growth was indicated by a shift in color from blue to red. Growing the strains properly was shown by a change in the color of the growth control wells to red, and the absence of contamination was indicated by no change in the color of a sterile control well. The experiment is performed three times, and mean values were reported.

2.7 Biofilm inhibition in vitro

With minor modifications, the microtiter plate (MTP) approach was used to assess the capacity of AgNPs and AuNPs to prevent or lessen the aggregation of biofilms in clinical species S. aureus and Pseudomonas aeruginosa (recognized as a prolific biofilm-producing strain) [71]. In a nutshell, tryptic soy broth media (TSB) with 1% glucose was added on a flat-bottomed MTP along with gradient concentrations of AgNPs and AuNPs. Test organisms were cultured overnight using a 1:100 dilution to achieve an inoculum size of 1.5 108 CFU/mL, which was subsequently loaded onto MTP and incubated at 37 °C for 48 h. In order to evaluate growth density, spectrophotometry was used (O.D. 620 nm), and following that, planktonic cells were removed from all of the MTP wells without causing any damage to the biofilm that had already grown. Furthermore, to remove the residue cells of floated unbounded cells, these wells were washed by phosphate‐buffered saline (PBS) at pH 7.4, three times. For fixation of biofilm, methanol 95% was added in equal volume 200 μL to all wells. After that, 200 μL of 0.3% crystal violet (CV 0.3%) was added to the same wells, then incubation of the plates at 20–25 °C for 15 min. Additionally, the excess of CV stain was gently removed by sterile distilled H2O. Lastly, CV stain bounded with biofilm, at this point was examined then photographed using an inverted microscope (Olympus Ck40) × 150. Adding 200 μL of 30% acetic acid to each well allowed for the quantitative measurement of biofilm development, and the microplate reader (Tecan Elx800) was used to measure the color at 540 nm. Results from treated and untreated wells were contrasted.

2.8 Anti-oxidant activity

2.8.1 DPPH screening

The DPPH (2, 2-diphenyl-1-picrylhydrazyl) technique was used to test the antioxidant capacity of AgNPs as well as AuNPs [72]. The amounts of DPPH radicals that were scavenged at various nanoparticle concentrations (1000 µg/mL, 500 µg/mL, 250 µg/mL, 125 µg/mL, 62.5 µg/mL, 31.25 µg/mL, and 15.62 µg/mL) were measured. Antioxidant activity of standard and NPs was determined as DPPH scavenging activity (%): [((control absorbance − extract absorbance)/ (control absorbance)) × 100].

2.9 Cytotoxicity and anticancer potential

2.9.1 Cell culture

The human mammary gland, breast, produced from a metastatic location, normal Vero cells (kidney of an African green monkey), and cancer cells (Mcf7-HTB-222) were purchased from ATCC.

2.9.2 MTT assay

A full monolayer sheet formed after 24 h of incubation at 37 °C with 1 × 105 cells/ml (100 μL) in the 96-well tissue culture plate. After a confluent sheet of cells had grown, the 96-well microtiter plates’ growth material was decanted, and the cell monolayer had been twice rinsed with washing media. In RPMI medium containing % serum, two-fold serial dilution of the sample was created (maintenance medium). Three wells served as the control wells and received just maintenance medium, while 0.1 ml of each dilution was tested in various wells. The plate was tested after 37 °C of incubation. The physical characteristics of cytotoxicity, such as problems such as loss of the monolayer, rounded, shrinking, or cellular granulation, were examined in the cells (5 mg/mL in PBS) of MTT solution has been created (BIO BASIC CANADA INC). To every well, 20 μL of the MTT solution was then added. To completely blend the MTT through into medium, put on a shaker and shake for five minutes at 150 rpm. Permit the MTT to metabolize for four hours in an incubator (37 ºC, 5% CO2). Get rid of the media (if required, dry plate on paper towels to get rid of any leftovers. In 200 μL of DMSO, resuspension of formazan (MTT metabolic product). For 5 min, shake at 150 rpm to properly combine the formazan and solvent. At 620 nm, remove background when reading optical density. Cell number and optical density ought to be closely connected [73].

3 Results and discussion

3.1 Screening of various soil fungi for biosynthesis of AgNPs and AuNPs

The most potent microorganism in the soil is fungi, which have a good potential for biofabriacted of metallic nanoparticles. The aim of our study is the isolation of different soil fungi species for mycosynthesize of silver and gold nanoparticles. In addition, this study aimed to evaluate both AgNPs and AuNPs in various biological activities including antimicrobial, antibiofilm, anticancer, and antioxidant efficacies. Among which, 15 soil samples were collected from various site in Qalyub governorate, Egypt. All the samples of soil were cultivated on Potatoes Dextrose Agar (PDA) medium, 30 individual fungal strains were isolated. Furthermore, screening for the capability of 30 isolates for synthesize of AgNPs and AuNPs were applied. Of them, 11 isolates showed positive synthesize for both nanoparticles; 5 of these species did so in less than eight hours. In addition, only 11 isolates produced AgNPs and only one species produced AuNPs. Out of the 14 species of Aspergillus that were continuously studied, 5 species continuously generated extracellular AgNPs and AuNPs, 5 isolates only produced AgNPs, and 1 species created gold NPs. Followed by Fusarium species, out of 6 strains tested, 4 have a better response for the mycosynthesis of AuNPs and/ or AgNPs, and alone one strain mycosynthesized AgNPs. Of the 4 species screened, 2 species of Penicillium have synthesized AgNPs and one biofabriacted the two nanoparticles. Three Trichoderma species was the two strains had been synthesized AgNPs and one with strong synthesize both of AgNPs and AuNPs. AgNPs did synthesize by one Mucor isolates from two isolated. Finally, the only species of Rhizopus was isolated not give any response to both metal nanoparticles. In current study, only one fungal isolate (TB-13c) showed high potency to produce AgNPs and AuNPs. During this whole study, Fusarium spp. (TB-13c) was identified as suitable strains for the extracellular fabrication of metallic nanoparticles depending on the particles durability and quicker rate of production (Fig. 1). Similar to this, several studies have used Fusarium spp. as prospective candidates for the formation of either silver or gold nanoparticles [41, 47, 74].

Fig. 1
figure 1

Morphological identification of Fusarium pseudonygamai TB-13c: A growth area on PDA; B colony opposite color; C and D conidiophore and conidia under optical microscope, respectively

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Molecular techniques were used to identify the fungal isolate Fusarium pseudonygamai TB-13c. Using PCR as well as sequential methods, the ITS segment of a filamentous fungi was discovered. We created a phylogenetic tree utilizing something such as a greatest probability approach to compare our ITS sequence to earlier identified sequences. According to Fig. 2, the outcomes demonstrated a 100% agreement between the sequenced ITS segment and the structure of Fusarium pseudonygamai TB-13c.

Fig. 2
figure 2

Phylogenetic tree incorporating the fungal strain TB-13c ITS sequences matching NCBI sequences, identified as Fusarium pseudonygamai

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3.2 Characterization of AgNPs and AuNPs

As NPs develop, their colors change, becoming brown for AgNPs and pinkish violet for AuNPs, respectively. UV–vis range significantly supports its manufacturing. Absorbance spectroscopy mostly in UV–vis spectrum, from 300 to nm wavelength, is referred to as UV–vis spectroscopy. This method is important when figuring out how NPs develop, aggregate, and remain stable. Noble nanoparticle such gold and silver have higher absorption wavelengths (max) that are between 500–550 nm and 400–450 nm, respectively. Consequently, we could verify that perhaps the correct NPs have indeed been generated whenever we notice the highest value in particular wavelength areas. There is a chance that NP will aggregate over time, which would also cause max to adjust more towards the relatively long wavelength range. The production of these AgNPs and AuNPs were primarily verified by UV–vis spectroscopy, with maximal assimilation occurring at 420 and 540 nm, respectively (Fig. 3).

Fig. 3
figure 3

UV–vis spectrophotometer of the mycosynthesized AgNPs and AuNPs

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TEM examination is the most efficient method for determining the morphological characteristics of mycosynthesized NPs, such as their shape and size. In Fig. 4A TEM image displayed well-distributed, almost spherical AgNPs, and in the center right corner displayed the SAED structure. AgNPs exhibited a particle size range of 5–20 nm, as seen in Fig. 4B. In contrast, AuNPs were spherical and 8–60 nm in size (Fig. 4C). Interestingly, the SAED pattern of AuNPs was also seen in Fig. 4D. The myco-fabricated NPs matched those from earlier research in regards to size and form [38, 40].

Fig. 4
figure 4

A TEM image of AgNPs, B SAED patterns of AgNPs, C TEM image of AuNPs, and D SAED patterns of AuNPs

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Figure 5 shows the XRD patterns of AgNPs and AuNPs. Four different diffraction peaks may be seen in each spectrum. Peaks are seen in the case of AgNPs at four values: 38.42°, 44.56°, 64.66°, and 77.75°. Peaks throughout AuNPs were shown at 2θ values: 38.56°, 44.74°, 64.87°, and 77.85°. These 4 peaks correspond to reflections from of the planes (111), (200), (220), and (311) of a face-centered cubic phase of AgNPs and AuNPs. The peak matching to the (111) plane is much stronger in both situations than the peaks belonging to the (200), (220), and (311) planes. This suggests that the nanoparticles may be predominantly oriented all along (111) planes. Consequently, the XRD investigation obviously demonstrates that the produced AgNPs and AuNPs are crystalline. These findings are consistent with previous research [75, 76].

Fig. 5
figure 5

XRD pattern of AgNPs and AuNPs biosynthesized by Fusarium pseudonygamai

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In the research lab, substances can be examined using FT-IR. The absorbance peaks in an infrared spectrum, primarily reflect on the vibrational frequencies between both the atomic bonds of the specimen undergoing examination, serve as the sample’s fingerprint. Due to the unique atomic bonds that each substance has, no two compounds with the same infrared spectrum are exactly comparable. As a result, infrared spectroscopy can be useful for qualitative investigation and improved identification of various materials. The peak sizes also fall within the range that reveals the quantity of substance present. Advanced software algorithms make this spectroscopy a great tool for quantitative analysis [77]. The metal–oxygen resonance is responsible for the peaks inside the area between 400 and 700 cm−1 of the FT-IR spectrum seen in Fig. 6. In this study, the formation of silver nanoparticles can be confirmed by the presence of a peaks at 510, 620 and 832 cm−1 belong to bending vibration of Ag–O. The occurrence of those same peaks with a little variance in the wavenumber has previously been described [78,79,80]. FT-IR analysis has been used to investigate the existence of secondary metabolites that cap and reduce silver nitrate precursor to AgNPs. The occurrence of several functional groups in Fusarium pseudonygamai extract was correlated with the presence of various IR bands. In this study, the IR spectra investigated for the silver nanoparticles revealed the absorption peaks at (I) 2851 and 2198 cm−1 (OH group of alcohols and phenols); (II) 1596 cm−1 and 1351 cm−1 (C = O stretching of carboxylic acid group); (IV) 1025 cm−1 (C–OH vibrations of the protein/polysaccharide). Additionally, Ag–O was assigned the characteristic bands at 832,620, and 510 cm−1. The above peaks were confirmed in the previous studies [81, 82]. Additionally, the O–H stretching vibration of the hydroxyl groups in alcohol and phenol is seen in the FTIR spectra of AuNPs with what appears to be a unique band at wavenumber 3073 cm−1. The band at 1630 cm−1 is due to asymmetric CH2 stretching. The band at 1534 cm−1 display aromatic rings. The aromatic ring and OH assignments do certainly imply the polyphenolic attachment towards the gold surface. Furthermore, the distinctive band for Au-O was designated at 1022 cm−1. It follows that the various metabolites present in the filtrate of the fungal strain play a major part in the production and size reduction of Ag and Au into a well-stabilized nano-form.

Fig. 6
figure 6

FTIR spectra of fungal filtrate, AgNPs and AuNPs biosynthesized by Fusarium pseudonygamai

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SEM image confirmed the existence of nanoparticles ranging in size from 10 to 61 nm for AgNPs as shown in Fig. 7A. The existence of metal Ag and Au was substantiated by EDX spectrum analysis, which exhibited peaks within their typical energy levels. The identification lines presented for the principal emission energies for Ag correlate to the peaks observed in the spectrum, providing confidence that Ag was accurately characterized wherein the peak situated approximately 3 and 4 keV (Fig. 7B). The nanoparticles revealed that spherical AuNPs with sizes ranging from 15 to 70 nm (Fig. 7C). Those maxima are directly related to the Ag characteristic. Similarly, an absorption peak obtained at ∼2 keV which is specifically related to characteristic of AuNPs obtained in the spectrum (Fig. 7D). The mass of Ag was 23.76% with atom of 6.18%, whereas for gold, it is 61.97% with atom of 10.17%. The Au-NPs and Ag-NPs were discovered to really be crystalline exhibiting oval as well as spherical shapes, correspondingly. SEM examination normally provides an in-depth picture resolution of something like the particles by assigning a focused beam of electrons over the surface and finding secondary or back-scattered electron signal. In comparison, EDX also was utilized to offer atomic identification and concentration profiles information. SEM–EDX was used to investigate the surface analysis, topology, structural organization, and energy dissemination of biologically synthesized nanoparticles in our work. Previous research found polydisperse AgNPs acquired with high-resolution pictures, indicating excellent crystallinity of the nanoparticles and a strong signal in the Ag area, verifying the production of AgNPs [83]. These study have established that metallic Ag nanocrystals have a characteristic optical maximum absorption about 3 keV cause considerable plasmon resonance.

Fig. 7
figure 7

SEM–EDX spectrum of mycosynthesize AgNPs (A and B) and SEM–EDX spectrum of mycosynthesize AuNPs (C and D)

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3.3 Minimum inhibitory concentration of AgNPs and AuNPs

The actions of AgNPs and AuNPs against harmful microorganisms are among their major benefits. As a result, the antibacterial effectiveness of mycosynthesized both AuNPs and AgNPs against pathogenic Gram-positive (MRSA and MSSA) and Gram-negative (P. aeruginosa and K. pneumonia) bacteria was initially examined. Inhibitory effects of various doses of AgNPs and AuNPs (15.62–1000 μg/ mL) were studied (Fig. 8). The results indicated that the MIC for AgNPs was 62.5 μg/ mL against MSSA, K. pneumoniae, and P. aeruginosa and 125 g/ mL against MRSA, whereas the MIC for AuNPs was 1000 μg/mL versus MRSA, MSSA, and K. pneumoniae and 500 μg/mL for P. aeruginosa. Additionally, AgNPs outperformed AuNPs in their ability to combat both Gram-positive as well as Gram-negative harmful microorganisms. According to another study, nanoparticles inhibit bacterial growth by binding with phosphorous moieties in DNA. This inhibits DNA replication, which lowers enzyme activity [84]. Additionally, it can prevent the generation of ATP, which results in cell death, and block the respiratory enzymes of bacterial cells. Additional alterations included membrane detachment, cytoplasmic shrinkage, and finally membrane of cell rupture [85, 86].

Fig. 8
figure 8

Antibacterial activity of AgNPs and AuNPs against different pathogenic bacteria

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3.4 Anti-biofilm of AgNPs and AuNPs

The antibiofilm efficacy of nanoparticles in this study shown variable effects against various bacteria. Accordingly, when used at concentrations below the MIC value, AuNPs showed the greatest efficacy against the development of biofilms caused by S. aureus and P. aeruginosa. Against P. aeruginosa, AuNPs at 250, 125, 62.5, 31.25, and 15.62 μg/mL decreased the production of biofilm by 89.24, 87.28, 86.3, 78.97, and 78.48%, respectively. Additionally, at concentrations below the lethal dosage without impairing bacterial growth, Au-NPs demonstrated significant biofilm prevention agent against S. aureus, with proportions of 92.9, 75.6, 75.1, 67.3, and 63.8%, respectively. Through inverted microscopy techniques, the impact of nanoparticles on the surface structure of the biofilm matrix was investigated. The results showed that the positive control sample had a biofilm matrix, while Au-NPs-treated wells showed less surface colonization and biofilm matrix in S. aureus. By dissolving the micro-colonies inside the specimen that was permitted to be treated in the range of 3000 to 0.02 µg/mL, the light microscopic images showed that the AuNPs had completely dispersed the biofilm Fig. 9. According to their respective quantitative and qualitative analyses, AuNPs reduced the growth of both S. aureus as well as P. aeruginosa biofilms during the initial stage. In contrast, AgNPs had a little inhibited effect against P. aeruginosa and S. aureus which inhibited up to 43.7% at 15.6 µg/mL, and 41.3% at 7.8 µg/mL for P. aeruginosa and no inhibition against S. aureus under MIC value. Another study found that AuNPs produced also with fungal strain Laccaria fraterna reduced biofilm growth in almost the same way. Our results were likewise phenotypically like that of Rajkumari et al. [87]. Utilizing Baicalin conjugated nanoparticles, they contributed to a reduction biofilm forming capability. The results of our crystal violet technique for biofilm inhibition corresponded to those of Khan et al. [88]. Past study by Estevez et al. showed that AgNPs can diffuse into the matrix and damaged cells in the biofilm’s intern al layer [89].

Fig. 9
figure 9

Light inverted microscopic images of S. aureus biofilm grown with various concentrations of AuNPs: a 0.0 mg/mL represents the positive control; b negative control; c, d, and e 3.0 and 2.0 µg/mL above the MIC value; e 0.5 µg/mL; f 0.125 µg/mL; 0. 062 µg/mL; h 0. 031; i 0.04 µg/mL; and j 0.02 µg/mL. At concentrations from 0.04 and 0.02 µg/mL, (i and j) bacteria have manifested as dispersed cells and are unable to assemble to form a typical biofilm

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3.5 Cytotoxicity of AgNPs and AuNPs

The shape of cells the first and most noticeable finding arising from exposure to nanoparticles or other toxic compounds is a change in cell shape and otherwise morphology of the cell in culture. As a result, the light inverted microscope may be developed to monitor damage to cellular shape and morphology as a result of AgNPs and AuNPs exposed dosage (Figs. 10 and 11). The normal cell line expanded continuously across the plates and displayed epithelial shape. Cells after treatment to various concentration of AgNPs or AuNPs eventually lost unique phenotypic characteristics. Additionally, at high concentrations of AgNPs and AuNPs, the cells exhibit full or partial breakdown of monolayer, cell granulation, rounding, or shrinkage as compared to control sample. The light inverted microscope picture demonstrated unequivocally that the damage induced in cell morphology is dosage dependent for AgNPs and AuNPs.

Fig. 10
figure 10

Effect of AgNPs (a) and AuNPs (b) on normal Vero cells at different concentration imaged by light inverted microscope

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Fig. 11
figure 11

Effect of AgNPs (a) and AuNPs (b) on cancer cells (Mcf7) at different concentration imaged by light inverted microscope

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3.6 MTT assay

The fundamental step in toxicology which explains the cellular reaction to a toxin is called a viability test. They often provide details on cell metabolism, cell growth, and induce apoptosis [90]. The MTT test is really a sensitive colorimetric technique measuring determining the total number of viabilities in cell multiplication and cytotoxic activity experiments. Moreover, Fig. 12 shows cell death including both healthy and malignant cells significantly dose-dependent also when subjected to various quantities of either AgNPs or AuNPs. In specifically, our IC50 of Vero cell was 695.34 μg/mL for AgNPs and 631.66 μg/mL for AuNPs. AgNPs’ IC50 for cancer cell (Mcf7) was 204.07 μg/mL, whereas AuNPs’ IC50 was 206.95 μg/mL. In particular to maintain the protection of humans, it is thus strongly advised that the therapy with AgNPs and AuNPs be carried out at concentrations lower than 695.34 μg/mL and 631.66 μg/mL, respectively. Employing unique and diverse malignant cells, different studies have thoroughly investigated the cytotoxic effects of AgNPs as well as AuNPs [91, 92]. A parallel recent study showed that AgNPs and AuNPs had an antitumor impact on carcinoma cell lines. AgNPs and AuNPs were reported to have IC50 values of 100 and 200 μg/mL, respectively [92]. As a result, our investigation demonstrated more toxicity on carcinoma cell lines compared to the earlier findings [91, 92]. Applying AuNPs for medical purposes, Hamed as well as some co-workers showed anticancer properties versus carcinoma cell lines [93].

Fig. 12
figure 12

Cytotoxicity (A) and antitumor activity (B) of AgNPs and AuNPs

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3.7 Antioxidant activity

Antioxidants are effective against reactive oxygen species (ROS), byproducts of biological activities [94]. Free radicals, which cause a range of diseases, may also be reduced by antioxidants [95]. Antioxidants were already considered as bioactive molecules provided; they show anticancer, antibacterial, anti-inflammatory, anti-mutagenic, anti-tumor, and anti-carcinogenic and properties. As shown in Fig. 13, the antioxidant activity of AgNPs and AuNPs was evaluated in this study using DPPH methods at a range of doses (1000–15.62 μg/mL). Results revealed that AgNPs had the strongest antioxidant activity comparing to AuNPs. AgNPs had an IC50 of 38.2 μg/mL as opposed to 180 μg/mL AuNPs. According to Pu et al., spherical AuNPs have stronger antioxidant potential than irregularly or polygonal ones [96]. In previous research, AgNPs showed strong DPPH efficacy with just an IC50 value of 30.04 μg/mL [97]. Our results confirm the outstanding antioxidant properties of AgNPs and AuNPs that have been previously described [98, 99].

Fig. 13
figure 13

Antioxidant activity of AgNPs and AuNPs by DPPH method

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4 Conclusion

The novel fungus Fusarium pseudonygamai is used in the present discovery to synthesize AgNPs and AuNPs, which is a very effective and environmentally beneficial process. The generation of AgNPs and AuNPs with sizes between 5–20 nm for AgNPs and 8–60 nm for AuNPs was mediated by Fusarium pseudonygamai filtrate. Different analytical methods were used to analyze the produced AgNPs and AuNPs, and they were discovered that the particles were extremely stable. Effective antibacterial, antibiofilm, antioxidant, and anticancer properties have been demonstrated by the biosynthesized AgNPs and AuNPs. On Mcf7 cells, these AgNPs and AuNPs had strong cytotoxic properties. In the world of medical biotechnology, this alternative biosynthesis process for AgNPs and AuNPs would compete with the widely used chemical approaches.