Search Results (48)

The results of our recent research revealed that biologically synthesized silver nanoparticles (bio-AgNPs) applied to several-day-old pea (Pisum sativum L.) plants or used for seed nanopriming protected pea plants against selected fungal pathogens. However, the susceptibility of pea to bio-AgNPs during seed germination remains mostly unknown. Therefore, in this study, we investigated the cells’ viability, ROS generation, total antioxidant capacity, the activity of selected antioxidant enzymes, and changes in the polar metabolite profiles of 4-day-old pea seedlings developed in water (control) and water suspensions of bio-AgNPs (at 50 and 200 mg/L). The bio-AgNPs did not negatively affect pea seeds’ germination, early seedlings’ growth, and root tips cells’ viability (at both tested concentrations). In the root, the bio-AgNPs at a lower concentration (50 mg/L) stimulated ROS generation. Nanoparticles enhanced peroxidase activity in root and the total antioxidant capacity in epicotyl. Increased levels of malate, phosphoric acid, proline, GABA, and alanine were observed in root and epicotyl of pea seedlings developed at 50 mg/L of bio-AgNPs. A higher concentration affected the tricarboxylic acid cycle and nitrogen metabolism. Bio-AgNPs alerted oxidative homeostasis and primary metabolism of pea seedlings but did not exceed a certain threshold limit and thus did not injure pea at an early stage of seedling development. Full article

Breast cancer is a leading cancer diagnosis for women around the world, with a variable degree of curability. Conventional chemotherapeutic treatments often induce toxicity and damage to healthy tissues, as well as the development of drug resistance, which is why an increasing number of new therapeutic regimens focus on the use of natural products and various modifications of their delivery to target tissues. Silver nanoparticles possess unique physicochemical characteristics, notably their increased surface area, suggesting that they hold significant potential for biomedical applications. This research evaluates the capacity of silver nanoparticles green synthesized with aqueous extracts of Filipendula ulmaria (FUAgNPs) and Salvia verticillata (SVAgNPs) to alter migration and redox homeostasis in the human breast cancer cell line MDA-MB-231. To determine the values of redox homeostasis parameters, the cells were treated with five different concentrations (5, 10, 20, 50, and 100 μg/mL) for 24 h and 72 h, while to test the migratory potential and concentrations of matrix metalloproteinase-9 (MMP-9) and nuclear factor erythroid 2–related factor 2 (Nrf-2), the cells were treated at two concentrations (5 and 50 µg/mL) for 72 h. The obtained results indicate increased production of superoxide anion radicals, malondialdehyde (MDA), and nitrites after the investigated treatment on MDA-MB-231 cells. The treatments induced only a slight elevation in Nrf-2 levels, which correlates with weak de novo synthesis of reduced glutathione (GSH), suggesting that the tested nanoparticles weaken the inherent antioxidative systems of the tested cells. The migration potential of cells was significantly reduced, and MMP-9 concentration was significantly inhibited. Based on the demonstrated antitumor effect, confirmed by the reduced migratory potential of the examined cells and disrupted redox balance, these nanoparticles have potential for additional investigation with the aim of improving the efficacy of antitumor therapy. Also, FUAgNPs and SVAgNPs possess the capacity to be potentially promising novel chemotherapeutic agents against breast cancer progression and metastasis. Full article

Silver nanoparticles belong to a highly versatile group of nanomaterials with an appealing range of potential applications. In the realm of antimicrobial and antioxidant application, silver nanoparticles (AgNPs) exhibit auspicious capabilities. This research, for the very first time, endeavors to carry out biosynthesis of AgNPs coupled with fermentation using Medusomyces gisevii and Origanum vulgare L. (O. vulgare) plant species. Fermentation (F) via Medusomyces gisevii is responsible for chemical, physical, biological, and electrochemical processes. During in vitro study of antioxidant activity, fermented O. vulgare herb extract showed strong reductive activity as evaluated by the cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) assay, with a value of 1.45 ± 0.048 mmol TE/g, 0.95 ± 0.04 mmol TE/g, and 0.59 ± 0.023 mmol TE/g, respectively. The highest antimicrobial activity was shown by Staphylococcus aureus in the inhibition zone, with values of 1.40 ± 0.12 mm of OrV and of 10.30 ± 0.04 mm and 11.54 ± 0.10 mm for OrV-AgNPs and OrV-F-AgNPs, respectively. Analysis of phenolic compounds revealed that the highest total amount of the apigenin, 87.78 µg/g, was detected in OrV-F-AgNPs and the lowest amount, 16.56 µg/g, in OrV-AgNPs. Moreover, in OrV-F-AgNPs, the collective amount of proanthocyanidins, hydroxycinnamic, and flavonoids was prominently high in all cases, i.e., 145.00 ± 0.02 mg EE/g DW, 2.86 ± 0.01 mg CAE/g DW, and 0.55 ± 0.01 mg RE/g DW, respectively, as compared to the original extract (102.1 ± 0.03 mg EE/g DW, 2.78 ± 0.02 mg CAE/g DW, and 0.47 ± 0.01 mg RE/g DW, respectively). During the characterization of biosynthesized nanoparticles by scanning electron microscopy (SEM), AgNPs demonstrated a uniform spherical shape with even distribution. The sample’s elemental composition was confirmed with a signal of 3.2 keV using energy-dispersive X-ray spectroscopy (EDS) analysis. Transmission electron microscopy (TEM) analysis showed silver nanoparticles that were round and spherical in shape in both stacked and congested form, with a size range of less than 30 nm. Thus, this green and sustainable synthesis of AgNPs, a blend of Medusomyces gisevii and O. vulgare herbal extract, has adequate potential for increased antimicrobial and antioxidant activity. Full article

Silver nanoparticles (AgNPs), synthesised using Chlorella vulgaris algal extract and silver nitrate, are studied in medicine for their antibacterial properties in poultry. This study assessed the effect of AgNPs on bacterial inhibition and early development and blood parameters in Ross 308 chicken embryos. AgNPs were characterised using transmission electron microscopy, scanning electron microscopy with a focused ion beam, UV–Vis spectroscopy, and a zetasizer. The antibacterial properties of the AgNP colloid against S. enterica were assessed using minimal inhibitory concentration, minimal bacterial concentration, and PrestoBlue assays. AgNP colloid (2 mg/L) was injected into egg albumen on day 0. Chicken embryos were incubated for 3 and 16 d. The effect of AgNPs on 3 d old embryos was evaluated based on mortality and somite count using the Hamburger–Hamilton classification. For older embryos, mortality, dimensions, anatomical changes, organ mass, plasma liver enzymes and antioxidants, and red blood cell morphology were determined. Blood samples from the control group embryos were assessed for the impact of AgNPs on hemolysis. AgNPs inhibited S. enterica growth at concentrations >6.75 mg/L. A 3 d exposure to AgNPs caused an insignificant decrease in the number of somites without affecting embryo mortality. However, a 16 d exposure to AgNPs reduced live embryos and plasma antioxidants, changed the levels of ALT, AST, and GGT, altered red blood cell morphology, and caused hemolysis. Toxicity of AgNPs was model-dependent, whereby the chicken embryo was more sensitive to AgNPs than the bacterium. Full article

(1) Background: Over 90% of hop crops are currently used in beer production, with a small part used in the cosmetics and pharmaceutical industries. Spent hops as a waste product contain one of the strongest antioxidants, xanthohumol. The aim of the study was to purify spent hop extracts by magnetic dispersive extraction using iron oxide nanoparticles (IONP) to obtain pure xanthohumol; (2) Methods: The extract from the waste product obtained after supercritical carbon dioxide extraction of hops was prepared by ultrasound-assisted extraction utilizing different solvents, i.e., ethyl acetate, propanol, acetone, 80% methanol, ethyl acetate-methanol (1:1, v/v), and propanol-methanol (1:1, v/v). The hydrodynamic diameters and zeta potential of IONPs before and after incubation were measured by dynamic light scattering (DLS). The extracts were analyzed by reversed-phase high-performance liquid chromatography (HPLC). Isolated xanthohumol was identified based on the DAD spectrum in the range of 200–600 nm and by Fourier transform infrared spectroscopy/attenuated total reflectance (FT-IR/ATR); The antioxidant activity of extracts before and after incubation with IONPs was assessed using SNPAC (Silver Nanoparticle Antioxidant Capacity), DPPH (2,2-diphenyl-1-picrylhydrazyl radical), and FRAP (Ferric Reducing Antioxidant Power) assays, as well as total phenolic content (TPC) and total flavonoid content (TFC). (3) Results: The amount of added IONPs, the kind of solvent, and the contact time of the extract with nanoparticles were optimized. We found that 80% MeOH extract after incubation with IONPs (865 µg IONPs/g of spent hops) at room temperature for 48 h contains 74.61% of initial xanthohumol content, providing a final xanthohumol concentration of 43 µg mL⁻¹. (4) Conclusions: The proposed method of magnetic dispersive extraction using IONPs allows for the purification of spent hops extract and obtaining a pure product, namely xanthohumol, with a wide potential for practical applications in medicine, pharmacy, cosmetics, and agriculture. This is clear evidence of the usefulness of IONP as an effective sorbent. The method allows the use of residues from the brewing industry, i.e., the biomass of used hop cones to obtain a valuable substance. Full article

The incorporation of silver nanoparticles (AgNPs) into alginate–gelatin (Alg-Gel) hydrogels can enhance the properties of these materials for bone regeneration applications, due to the antimicrobial properties of AgNPs and non-cytotoxic concentrations, osteoinductive properties, and regulation of stem cell proliferation and differentiation. Here, the hydrogel formulation included 2% (w/v) sodium alginate, 4 µg/mL AgNPs, and 2.5% (w/v) gelatin. AgNPs were synthesized using a 2% (w/v) aqueous extract of roasted green tea with silver nitrate. The aqueous extract of roasted green tea for AgNP synthesis was characterized using HPLC and UHPLC-ESI-QTOF-MS/MS, and antioxidant capacity was measured in Trolox equivalents (TE) from 4 to 20 nmol/well concentrations. Stem cells from human exfoliated deciduous tooth cells were used for differentiation assays including positive (SHEDs/hydrogel with AgNPs) and negative controls (hydrogel without AgNPs). FTIR was used for hydrogel chemical characterization. Statistical analysis (p < 0.05, ANOVA) confirmed significant findings. Roasted green tea extract contained caffeine (most abundant), (−)-Gallocatechin, gallic acid, and various catechins. XRD analysis revealed FCC structure, TEM showed quasispheroidal AgNPs (19.85 ± 3 nm), and UV–Vis indicated a plasmon surface of 418 nm. This integration of nanotechnology and biomaterials shows promise for addressing bone tissue loss in clinical and surgical settings. Full article

Antioxidants of plant extract play an important role in the phytosynthesis of silver nanoparticles (phyto-AgNPs), providing the reduction of silver ions and capping and stabilization of nanoparticles. Despite the current progress in the studies of phytosynthesis, there is no approach to the selection of plant extract for obtaining phyto-AgNPs with desired properties. This work shows that antioxidant activity (AOA) of plant extracts is a key parameter for targeted phytosynthesis. In support of this fact, the synthesis of phyto-AgNPs was carried out using extracts of four plants with different AOA, increasing in the order Ribes uva-crispa < Lonicera caerulea < Fragaria vesca < Hippophae rhamnoides. Phyto-AgNPs have been characterized using Fourier-transform infrared spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, selected area electron diffraction technique, ultraviolet–visible spectroscopy, electrochemical impedance spectroscopy and cyclic voltammetry. It was established that the change in the AOA of the plant extract is accompanied by a size-dependent change in the optical and electrochemical properties of phyto-AgNPs. In particular, an increase in the extract AOA leads to the formation of smaller phyto-AgNPs with higher electrochemical activity and low charge transfer resistance. A “blue shift” and an increase in the plasmon resonance band of silver sols are observed with an increase in the extract AOA. The obtained regularities prove the existence of the “AOA–size–properties” triad, which can be used for controlled phytosynthesis and prediction of phyto-AgNPs’ properties. Full article

Background: Heracleum sphondylium, a medicinal plant used in Romanian ethnopharmacology, has been proven to have remarkable biological activity. The escalating concerns surrounding antimicrobial resistance led to a special attention being paid to new efficient antimicrobial agents based on medicinal plants and nanotechnology. We report the preparation of a novel, simple phytocarrier that harnesses the bioactive properties of H. sphondylium and silver nanoparticles (HS-Ag system). Methods: H. sphondylium’s low metabolic profile was determined through gas chromatography–mass spectrometry and electrospray ionization–quadrupole time-of-flight–mass spectrometry. The morphostructural properties of the innovative phytocarrier were analyzed by X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, dynamic light scattering, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The antioxidant activity was evaluated using total phenolic content, ferric reducing antioxidant power, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) in vitro assays. The antimicrobial activity screening against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli was conducted using the agar well diffusion method. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay estimated the in vitro potential cytotoxicity on normal human dermal fibroblasts (NHDF) and cervical cancer (HeLa) cells. Results: A total of 88 biomolecules were detected, such as terpenoids, flavonoids, phenolic acids, coumarins, phenylpropanoids, iridoids, amino acids, phytosterols, fatty acids. The HS-Ag phytocarrier heightened efficacy in suppressing the growth of all tested bacterial strains compared to H. sphondylium and exhibited a significant inhibition of HeLa cell viability. Conclusions: The new HS-Ag phytocarrier system holds promise for a wide range of medical applications. The data confirm the capacity to augment the pertinent theoretical understanding in the innovative field of antimicrobial agents. Full article

Quercus species are utilized for their durable wood, providing sustenance for wildlife, conserving biodiversity, and contributing ecological, medicinal, and esthetic benefits to ecosystems and landscapes. In this study, we aimed to use the bark of three Quercus species (Q. dalechampi, Q. fraineto, and Q. petraea) for the synthesis of silver and gold nanoparticles (AgNPs and AuNPs). The aqueous extracts from the bark of Quercus sp. acted both as reducing and stabilizing agent, facilitating the rapid synthesis of AuNPs (AuQD, AuQF, and AuQP) and AgNPs (AgQD, AgQF, and AgQP). The obtained nanoparticles were characterized using UV-vis spectroscopy, TEM, DLS, and FTIR. Characterizations revealed that the nanoparticles exhibited a variety of shapes, such as polygonal, triangular, and spherical forms, with sizes ranging between 14 and 24 nm for AuNPs and 45–70 nm for AgNPs. The total phenolic content was assessed through spectroscopic methods, while several individual phenolic compounds were identified and quantified using UPLC-PDA. Furthermore, we assessed the antioxidant, antibacterial, and antifungal capacities of AuNPs, AgNPs, and raw extracts. The highest antioxidant activity was observed for raw extracts, followed by AgNPs and AuNPs, while the most potent antibacterial and antifungal activity was observed in AgQP. Moreover, cytotoxicity was examined in a human keratinocyte cell line (HaCaT). The results indicated no cytotoxic effects for AuNPs, while AgNPs and the raw extracts exhibited cytotoxic effects after 48 h of incubation. This research underscores the multifaceted utility of Quercus bark extracts in the green synthesis of metallic nanoparticles and their subsequent bioactivity assessment, suggesting promising perspectives for their application in various fields while urging cautious consideration of their cytotoxic implications. Full article

Recent focus has been given to nanoparticles as an alternative fungicidal compound instead of chemical ones. More environmentally friendly ways of synthesis are the highest priority regarding the antifungal agents in the agriculture sector. Therefore, in this research, hyssop (H. officinalis) and sage (S. officinalis) aqueous extracts were prepared and used as a reducing source in the green synthesis of silver nanoparticles (AgNPs). Aqueous extracts and green synthesized AgNPs were examined for phytochemical composition and antioxidant capacity. Hyssop and sage extracts based AgNPs were analyzed using UV-vis spectrometry, SEM-EDS, and TEM-EDS. Antifungal activity against Fusarium spp. isolates collected from different infected crops was determined. Fusarium spp. isolates from strawberry, asparagus, pea, carrot, wheat, and rapeseed samples identified at the molecular level by translation elongation factor 1-alpha (TEF1α) gene amplification and sequencing. Green synthesized AgNPs had lower phytochemical content, however higher antioxidant activity compared to pure extracts. Both hyssop and sage extracts are suitable reducing agents for AgNPs formation, and sage extract results in larger particle size. Aqueous hyssop extract had higher antifungal activity than aqueous sage extract. However, a 10% concentration of whole sage extract based AgNPs solution, added to the PDA medium, and a 5% concentration of hyssop extract based AgNPs inhibited Fusarium spp. the most. F. proliferatum was the most sensitive to all treatments among the other fungi. Full article

Lignin-poly(ethylene)glycol diglycidyl ether hydrogels were synthesized from lignin fractions readily extracted during the hot-water treatment of angiosperms: hardwoods, sugar maple and energy-crop willow, monocotyledons, grasses, miscanthus and agriculture residues, and wheat straw. These lignins represent a broad range of chemical structures and properties as a comparative analysis of their suitability to produce the hydrogels as a novel carrier of chaga–silver nanoparticles. The formation of hydrogels was assessed via attenuated total reflectance Fourier-transformed infrared spectroscopy. Then, the hydrogels were observed via scanning electron microscopy and evaluated for their free-absorbency capacity and moduli of compression. Furthermore, a hydrogel produced from kraft lignin and two commercial hydrogels was evaluated to benchmark the effectiveness of our hydrogels. Chaga extracts were prepared via the hot-water extraction of chaga mushroom, a method selected for its relatively higher yields and preserved antioxidizing activities. Hydrogels synthesized with lignins of monocotyledons, wheat straw, and miscanthus were found to be suitable carriers for chaga–silver nanoparticles due to their favorable absorption and release behaviors. Full article

Iron oxide nanoparticles (IONPs) have many practical applications, ranging from environmental protection to biomedicine. IONPs are being investigated due to their high potential for antimicrobial activity and lack of toxicity to humans. However, the biological activity of IONPs is not uniform and depends on the synthesis conditions, which affect the shape, size and surface modification. The aim of this work is to synthesise IONPs using a mixed method, i.e., chemical co-precipitation combined with biogenic surface modification, using extracts from spent hops (Humulus lupulus L.) obtained as waste product from supercritical carbon dioxide hop extraction. Different extracts (water, dimethyl sulfoxide (DMSO), 80% ethanol, acetone, water) were further evaluated for antioxidant activity based on the silver nanoparticle antioxidant capacity (SNPAC), total phenolic content (TPC) and total flavonoid content (TFC). The IONPs were characterised via UV-vis spectroscopy, scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS) and Fourier-transform infrared (FT-IR) spectroscopy. Spent hop extracts showed a high number of flavonoid compounds. The efficiency of the solvents used for the extraction can be classified as follows: DMSO > 80% ethanol > acetone > water. FT-IR/ATR spectra revealed the involvement of flavonoids such as xanthohumol and/or isoxanthohumol, bitter acids (i.e., humulones, lupulones) and proteins in the surface modification of the IONPs. SEM images showed a granular, spherical structure of the IONPs with diameters ranging from 81.16 to 142.5 nm. Surface modification with extracts generally weakened the activity of the IONPs against the tested Gram-positive and Gram-negative bacteria and yeasts by half. Only the modification of IONPs with DMSO extract improved their antibacterial properties against Gram-positive bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Micrococcus luteus, Enterococcus faecalis, Bacillus cereus) from a MIC value of 2.5–10 mg/mL to 0.313–1.25 mg/mL. Full article

The beneficial application of silver nanoparticles and biostimulants to increase crop yield and quality is a long-term strategy to achieve desired agricultural productions that are resilient to various biotic and abiotic challenges. This project aimed to evaluate the individual effects of silver nanoparticles (AgNPs), Ascophyllum nodosum (SEW), and Spirulina platensis (SP) on the growth and physiological responses of Santolina chamaecyparissus. S. chamaecyparissus plants were exposed to AgNPs (20, 40, and 60 mg L⁻¹), SWE (0.5% and 1%), and SP (1%, 2%, and 3%). The finding indicates that the light-harvesting efficiency and plant photochemical capacity are not affected by most treatments except for 60 mg L⁻¹ AgNPs. Furthermore, the pattern of H₂O₂ levels in leaves was significantly higher after AgNP, SP, and SEW treatments. In parallel, total phenolic production was at least accompanied by a burst in H₂O₂ levels. However, higher antioxidant activity compared to the control, is shown by the higher free-DPPH-radical inhibition that goes completely smoothly with lower H₂O₂ levels. Thus, the results of the present study showed that biostimulants overall improved the antioxidant activity of S. chamaecyparissus and induced variable detectable amounts of phenolic compounds in response to the concentrations of each biostimulant. Full article

Cymbopogon citratus is commonly used in folk medicine for the treatment of nervous and gastrointestinal disturbances and other medical issues because of its potent antioxidant capacity. The current study evaluated the anti-candida effects of silver nanoparticles (AgNPs) synthesized from an aqueous extract of C. citratus against different Candida spp. The aqueous extract was prepared from the fresh leaves of C. citratus. The silver nanoparticles (AgNPs) were prepared and validated by UV spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscope (TEM), and zeta size analysis. C. albicans, C. krusei, C. parapsilosis, C. tropicalis, C. famata, C. rhodotorula, and C. glabrata were used in the antifungal assay. Microscopical imaging were used to investigate the different morphological changes induced by treatment. FTIR spectrum confirmed the existence of various functional groups of biomolecules capping the nanoparticles. The average particle size of synthesized AgNPs was 100.6 nm by zeta-sizer and 0.012 to 0.059 mm by TEM. In the antifungal assay, AgNPs aggregates induced significant inhibition of the growth of all species (p < 0.05) compared to the control and the biofilm maturation in C. famata and C. albicans. These considerable antifungal activities might lead to the development of appropriate alternative remedy for the treatment of fungal infections. Full article

Harmful algal blooms impact human welfare and are a global concern. Sargassum spp., a type of algae or seaweed that can potentially bloom in certain regions of the sea around Thailand, exhibits a noteworthy electron capacity as the sole reducing and stabilizing agent, which suggests its potential for mediating nanoparticle composites. This study proposes an eco-friendly microwave-assisted biosynthesis (MAS) method to fabricate silver nanoparticles coated with Sargassum aqueous extract (Ag/AgCl-NPs-ME). Ag/AgCl-NPs-ME were successfully synthesized in 1 min using a 20 mM AgNO₃ solution without additional hazardous chemicals. UV–visible spectroscopy confirmed their formation through a surface plasmon resonance band at 400–500 nm. XRD and FTIR analyses verified their crystalline nature and involvement of organic molecules. TEM and SEM characterization showed well-dispersed Ag/AgCl-NPs-ME with an average size of 36.43 nm. The EDS results confirmed the presence of metallic Ag⁺ and Cl⁻ ions. Ag/AgCl-NPs-ME exhibited significant antioxidant activity against free radicals (DPPH, ABTS, and FRAP), suggesting their effectiveness. They also inhibited enzymes (tyrosinase and ACE) linked to diseases, indicating therapeutic potential. Importantly, the Ag/AgCl-NPs-ME displayed remarkable cytotoxicity against cancer cells (A375, A549, and Caco-2) while remaining non-toxic to normal cells. DNA ladder and TUNEL assays confirmed the activation of apoptosis mechanisms in cancer cells after a 48 h treatment. These findings highlight the versatile applications of Ag/AgCl-NPs-ME in food, cosmetics, pharmaceuticals, and nutraceuticals. Full article