Green Fabrication of Bioactive Silver Nanoparticles Using Mentha pulegium Extract under Alkaline: An Enhanced Anticancer Activity

Rhus vulgaris Meikle fruit-mediated silver nanoparticles: Synthesis, characterization, and potential for sun protection, antioxidant and antibacterial applications

This study investigates the synthesis of silver nanoparticles (AgNPs) using Rhus vulgaris fruit extract (RVFE) and evaluates their antioxidant, antibacterial, and UV protection properties. R. vulgaris, a member of the Anacardiaceae family, is known for its rich phytochemical profile, including phenols, glycosides, alkaloids, saponins, tannins, and terpenoids, which contribute to its medicinal properties. The AgNPs were synthesized by mixing RVFE with silver nitrate (AgNO₃) under optimized conditions: a temperature of 80 °C, a pH of 9, a reaction time of 40 minutes, and a 9:1 AgNO₃-to-RVFE ratio. Characterization of the synthesized AgNPs was performed using UV-Vis spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), and zeta potential analysis. The results confirmed the successful synthesis, with AgNPs exhibiting an average size of approximately 14.64 ± 0.4 nm and a zeta potential of -26.0 mV, indicating good stability. The antioxidant activity was assessed using the DPPH radical scavenging assay, revealing a maximum inhibition of 53.7% ± 0.12% with an IC₅₀ value of 81.2 μg/mL. Antibacterial tests demonstrated significant activity against various bacterial strains, with inhibition zones ranging from 23.88 ± 1.10 mm to 30.21 ± 1.21 mm, indicating a stronger effect against Gram-negative bacteria. Additionally, the synthesized AgNPs exhibited a high Sun Protection Factor (SPF) of 234.5, suggesting their potential as effective UV blockers.This study highlights the promising applications of AgNPs-RVFE in biotechnology, medicine, and healthcare, emphasizing their eco-friendly synthesis and significant biological activities.

Phytosynthesis of anisotropic silver and gold nanoparticles: characterization and anticancer activity towards HIO180 and HeyA8 cells

Nature-inspired synthesis of metal nanoparticles (MNP) has long been a topic of interest among the researcher community. Herein, we report the synthesis of anisotropic Silver nanoparticles (AgNPs) and Gold nanoparticles (AuNPs) by Bombax Ceiba (B.C.) leaf extract. The crystal structure of the synthesized MNPs were thoroughly analyzed by various characterization techniques as UV-Vis, XRD, TEM, DLS, and Zeta potential. The chemical composition of the B.C. leaf extract was analysed by HR-LCMS and IR spectroscopy. The biogenic synthesized anisotropic AgNPs and AuNPs shows good anticancer activity against HIO180 and HeyA8 cells. The IC50 values of AgNPs for HIO180 and HeyA8 cells were 45.8 ± 6.4 and 29.03 ± 4.1 μg·mL-1 respectively. In case of AuNPs, the IC50 values for HIO180 and HeyA8 cells were >60 and 54.6 ± 9.1 μg·mL-1 respectively. According to the findings, the now presented biogenic technique offers a high promise for the simple and quick production of novel multifunctional nanoparticles for cancer cell tracking.

Calcium-ion-driving assembly of polysaccharide deriving from Zizyphus jujuba to hemostatic hydrogel for treating diabetic wound

Due to good biocompatibility and biodegradable, natural polysaccharide-based hydrogels have received worldwide attentions, where polysaccharide polymers were usually chemically modified to meet the specific elastic requirements. However, it remained highly challenging to develop polysaccharide-based hydrogels with desired mechanical properties and biological functions devoid of any structural modifications. Herein, with the coordination of Ca2+ (15.0 mM), the jujuba polysaccharide (JPS, 1 %) was facilely fabricated to a hydrogel (JPS-gel) within 1 min at pH 10, where the residual proteins also played crucial roles on the assembly. The JPS-gel showed outstanding stability and mechanical properties, which were tunable by adjusting the content of Ca2+/JPS. The JPS-gel also revealed excellent biocompatibility, and could expedite the migration and proliferation of healing-related cells, angiogenesis and alleviate inflammation response. More interestingly, the JPS-gel had hemostatic capacity, where the hemostatic time and blood loss in liver incision model were 13 ± 3 s and 6.3 ± 1.6 mg after 120 s treatment with JPS-gel, respectively. All these superiorities endowed JPS-gel high performance healing in diabetic wounds (10 days). Specially, the expressions of inflammation-related genes were downregulated, but gene expressions associated with cell migration and proliferation, and angiogenesis were upregulated, thus uncovering the action mechanism of JPS-gel on accelerating wound contraction.

Green synthesis of silver nanoparticles using Amomum nilgiricum leaf extracts: preparation, physicochemical characterization and ameliorative effect against human cancer cell lines

The present study to production of silver nanoparticles (AgNPs) by leaf extracts of A. nilgiricum and to evaluate the activity of anticancer by using AgNPs against cancer cell lines such as MCF-7, HEPG2, H9C2, HEK293 and H1975. The synthesized AgNPs were characterized by using UV-Vis spectroscopy, EDS, FT-IR, XRD, DLS, SEM and HRTEM with SAED patterns. The surface plasmon resonance (SPR) of AgNPs formed a peak centered at 427 nm by UV-Vis analysis. FTIR analysis reveals that existence of functional groups subjected to silver ions reduction to metallic silver. Crystalline form of the AgNPs was assessed by XRD analysis, four spectral peaks at 111, 200, 220, and 311 were formed and zeta potential peak was found at 28.5 mV indicating the higher stability. The size average diameter of the AgNPs was between 27 and 30 nm by TEM and SEM analysis was reveals the morphology of AgNPs as elongated, irregular and aggregated and some particles are spherical. EDX analysis confirmed the elemental composition of AgNPs with 81.43% Ag. The average diameter of AgNPs was found 21.49 nm in diameter and width was about 12.01 nm by DLS analysis. Cytotoxicity of AgNPs was investigated by using MTT, SRB assay and comet assay was performed as a genotoxicity. The results revealed that AgNPs decreased the viability of cancer cells in a concentration dependent pattern (50 to 350 µg/ml). The influence of AgNPs on cell cycle stop was studied on H1975, HEP-G2 and MCF-7 cells and found that AgNPs could induce sub G0 cell cycle arrest. The AgNPs was also induced DNA fragmentation confirms the DNA damage in nanoparticles treated cell lines. The anticancer action of nanoparticles was analyzed using proapoptotic and antiapoptotic caspase 8 and caspase 3 mRNA expression levels. Finally the results suggested that AgNPs is an effective anticancer agent which induces apoptosis in H1975, HEP-G2 and MCF-7 cells. Based on our studies, further identification of the major compounds of leaf extracts is acceptable.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-024-00674-7.

Citrus maxima extract-coated versatile gold nanoparticles display ROS-mediated inhibition of MDR-Pseudomonas aeruginosa and cancer cells

The expanding prevalence of microbial resistance to conventional treatments has triggered a race to develop alternative/improved strategies to combat drug-resistant microorganisms in an efficient manner. Here, the lethal impact of the biosynthesized gold nanoparticles (AuNPs) against multi-drug resistant (MDR) bacteria has been elucidated. AuNPs, synthesized from the extracts of the fruit, leaf and peel of the Citrus maxima plant, were physicochemically characterized by UV-Vis spectrophotometry, Dynamic Light Scattering (DLS), electron microscopy and spectroscopic techniques not only confirmed the production of AuNPs of size below 100 nm but also identified the phytochemicals adsorbed onto the surface of NPs. AuFeNP not only showed excellent antioxidant activity (∼95 % at 1 mg/mL) but also exhibited a commendable antimicrobial activity against MDR-Pseudomonas aeruginosa as assessed by the zone of inhibition (13.5 mm) and microwell broth dilution assays (9.5 μg/mL, MIC). Transmission electron microscopy (TEM) displayed bacterial cell membrane destruction post-AuNPs exposure. The killing mechanism of AuNPs elucidated the permeabilization of the cell membrane and generation of reactive oxygen species (ROS), ∼10-fold high depletion of GSH, and eventually leaching protein out of the cell. DNA damage, as a marker of apoptosis, was also noticed, which could be an implication of ROS accumulation in MDR-PA. AuNPs displayed significant toxicity at ∼ 10 μg/mL on various cancer cells (HT-1080, MRC-5, MDA-MB-231 and B16-F10) and relatively low toxicity on normal cells (MRC-5 and HaCaT). Scratch assay to identify the migration capability of breast cancer cells on treatment with AuNPs deciphered hampering of migration potential of breast cancer cells. Apoptotic topographies in B16-F10 cells were confirmed using AO/EtBr dual dye staining, DNA fragmentation, Caspase-3 assay and cell cycle analysis using flow cytometry. Hemolysis revealed minimal toxicity of AuNPs on human red blood cells. Nominal toxicity (∼70 % survival at 500 μg/mL of AuNPs) on mammalian cells was evaluated using Cell Titer-Glo cell viability assay. Overall results advocate the promising potential of biosynthetic AuFeNP against multi-drug-resistant pathogens and for further formulation into anticancer agents.

Harnessing Desmochloris edaphica Strain CCAP 6006/5 for the Eco-Friendly Synthesis of Silver Nanoparticles: Insights into the Anticancer and Antibacterial Efficacy

Microalgae-mediated nanoparticle (NP) biosynthesis is a promising green synthesis method that overcomes the challenges of conventional synthesis methods. The novel Desmochloris edaphica strain CCAP 6006/5 was isolated, purified, and characterized morphologically and genetically. GC-MS analysis of the algal biomass (DBio) phytochemicals showed the abundance for elaidic acid (18.36%) and monoolein (17.37%). UV-VIS spectroscopy helped analyze the effects of the AgNO3 concentration, algal/silver nitrate ratio, temperature, reaction time, illumination, and pH on AgNP synthesis. DBio extract or cell-free medium (DSup) of D. edaphica successfully biosynthesized small silver NPs (AgNPs), namely, DBio@AgNPs and DSup@AgNPs, under optimum reaction conditions. TEM and SEM showed a quasi-spherical shape, with average diameters of 15.0 ± 1.0 nm and 12.0 ± 0.8 nm, respectively. EDx and mapping analyses revealed that silver was the main element, the NP hydrodynamic diameters were 77.9 and 62.7 nm, and the potential charges were -24.4 and -25.8 mV, respectively. FTIR spectroscopy revealed that the DBio@AgNPs, and DSup@AgNPs were coated with algal functional groups, probably derived from algal proteins, fatty acids, or polysaccharides, representing reductant and stabilizer molecules from the synthesis process. They showed significant anticancer activity against breast cancer cells (MCF-7), low toxicity against normal kidney cells (Vero), and potent inhibitory activity against Staphylococcus aureus, Bacillus subtilis, and Shigella flexneri. D. edaphica is a novel biomachine for synthesizing small, stable and potent therapeutic AgNPs.

Plant-assisted green preparation of silver nanoparticles using leaf extract of Dalbergia sissoo and their antioxidant, antibacterial and catalytic applications

Plant-mediated preparation of silver nanoparticles (AgNPs) is thought to be a more economical and environmentally benign process in comparison to physical and chemical synthesis methods. In the present study, the aqueous leaf extract of Dalbergia sissoo was prepared and utilized to reduce silver ion (Ag+) during the green synthesis of silver nanoparticles (DL-AgNPs). The formation of DL-AgNPs was verified using UV-Vis spectra, exhibiting the surface plasmon resonance (SPR) band at around 450 nm. FT-IR analysis revealed the kinds of phytochemicals that serve as reducing and capping agents while DL-AgNPs are being synthesized. Analysis of scanning electron microscope (SEM) and high-resolution transmission electron microscopy (HR-TEM) images verified the development of spherical and oval-shaped DL-AgNPs, with sizes ranging from 10 to 25 nm. The stability and particle size distribution of synthesized DL-AgNPs were ensured by zeta potential and DLS (dynamic light scattering) investigations. Additionally, X-ray diffraction (XRD) analysis confirmed the crystalline nature of DL-AgNPs. In antioxidant experiments, DL-AgNPs demonstrated significant scavenging capacities of DPPH and ABTS radicals with EC50 values of 51.32 and 33.32 μg/mL, respectively. The antibacterial activity of DL-AgNPs was shown to be significant against harmful bacteria, with a maximum zone of inhibition (21.5 ± 0.86 mm) against Staphylococcus aureus. Furthermore, DL-AgNPs exhibited effective catalytic activity to degrade environment-polluting dyes (methylene blue, methyl orange, and Congo red) and toxic chemicals (p-nitrophenol). The results of all these studies suggested that DL-AgNPs made from the leaf extract of Dalbergia sissoo have merit for application in the environmental and biomedical fields.

Biogenic Salvia species synthesized silver nanoparticles with catalytic, sensing, antimicrobial, and antioxidant properties

Salvia (Lamiaceae family) is used as a brain tonic to improve cognitive function. The species including S. plebeia and S. moorcroftiana are locally used to cure hepatitis, cough, tumours, hemorrhoids, diarrhoea, common cold, flu, and asthma. To the best of authors' knowledge, no previous study has been conducted on synthesis of S. plebeia and S. moorcroftiana silver nanoparticles (SPAgNPs and SMAgNPs). The study was aimed to synthesize AgNPs from the subject species aqueous and ethanol extracts, and assess catalytic potential in degradation of standard and extracted (from yums, candies, and snacks) dyes, nitrophenols, and antibiotics. The study also aimed at AgNPs as probe in sensing metalloids and heavy metal ions including Pb2+, Cu2+, Fe3+, Ni2+, and Zn2+. From the results, it was found that Salvia aqueous extract afforded stable AgNPs in 1:9 and 1:15 (quantity of aqueous extract and silver nitrate solution concentration) whereas ethanol extract yielded AgNPs in 1:10 (quantity of ethanol extract and silver nitrate solution concentration) reacted in sunlight. The size of SPAgNPs and SMAgNPs determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were 21.7 nm and 19.9 nm, with spherical, cylindrical, and deep hollow morphology. The synthesized AgNPs demonstrated significant potential as catalyst in dyes; Congo red (85 %), methylene blue (75 %), Rhodamine B (<50 %), nitrophenols; ortho-nitrophenol (95-98 %) and para-nitrophenol (95-98 %), dyes extracted from food samples including yums, candies, and snacks. The antibiotics (amoxicillin, doxycycline, levofloxacin) degraded up to 80 %-95 % degradation. Furthermore, the synthesized AgNPs as probe in sensing of Pb2+, Cu2+, and Fe3+ in Kabul river water, due to agglomeration, caused a significant decrease and bathochromic shift of SPR band (430 nm) when analyzed after 30 min. The Pb2+ ions was comparatively more agglomerated and chelated. Thus, the practical applicability of AgNPs in Pb2+ sensing was significant. Based on the results of this research study, the synthesized AgNPs could provide promising efficiency in wastewater treatment containing organic dyes, antibiotics, and heavy metals.

Green Synthesis of Silver Nanoparticles Using the Cell-Free Supernatant of Haematococcus pluvialis Culture

The green synthesis of silver nanoparticles (AgNPs) using the cell-free supernatant of a Haematococcus pluvialis culture (CFS) was implemented in the current study, under illumination conditions. The reduction of Ag+ to AgNPs by the CFS could be described by a pseudo-first-order kinetic equation at the temperature range tested. A high reaction rate during synthesis and stable AgNPs were obtained at 45 °C, while an alkaline pH (pH = 11.0) and a AgNO3 aqueous solution to CFS ratio of 90:10 (v/v) proved to be the most effective conditions in AgNPs synthesis. A metal precursor (AgNO3) at the concentration range tested (1-5 mM) was the limited reactant in the synthesis process. The synthesis of AgNPs was accomplished under static and agitated conditions. Continuous stirring enhanced the rate of reaction but induced aggregation at prolonged incubation times. Zeta potential and polydispersity index measurements indicated stable AgNPs and the majority of AgNPs formation occurred in the monodisperse phase. The X-ray diffraction (XRD) pattern revealed the face-centered cubic structure of the formed AgNPs, while TEM analysis revealed that the AgNPs were of a quasi-spherical shape with a size from 30 to 50 nm. The long-term stability of the AgNPs could be achieved in darkness and at 4 °C. In addition, the synthesized nanoparticles showed antibacterial activity against Escherichia coli.

Hierarchy of hybrid materials. Part-II: The place of organics-on-inorganics in it, their composition and applications

Hybrid materials or hybrids incorporating organic and inorganic constituents are emerging as a very potent and promising class of materials due to the diverse but complementary nature of their properties. This complementarity leads to a perfect synergy of properties of the desired materials and products as well as to an extensive range of their application areas. Recently, we have overviewed and classified hybrid materials describing inorganics-in-organics in Part-I (Saveleva, et al., Front. Chem., 2019, 7, 179). Here, we extend that work in Part-II describing organics-on-inorganics, i.e., inorganic materials modified by organic moieties, their structure and functionalities. Inorganic constituents comprise of colloids/nanoparticles and flat surfaces/matrices comprise of metallic (noble metal, metal oxide, metal-organic framework, magnetic nanoparticles, alloy) and non-metallic (minerals, clays, carbons, and ceramics) materials; while organic additives can include molecules (polymers, fluorescence dyes, surfactants), biomolecules (proteins, carbohydtrates, antibodies and nucleic acids) and even higher-level organisms such as cells, bacteria, and microorganisms. Similarly to what was described in Part-I, we look at similar and dissimilar properties of organic-inorganic materials summarizing those bringing complementarity and composition. A broad range of applications of these hybrid materials is also presented whose development is spurred by engaging different scientific research communities.

Facile and Green Fabrication of Highly Competent Surface-Modified Chlorogenic Acid Silver Nanoparticles: Characterization and Antioxidant and Cancer Chemopreventive Potential

The eco-friendly, cost-effective, and green fabrication of nanoparticles is considered a promising area of nanotechnology. Here, we report on the green synthesis and characterization of bovine serum albumin (BSA)-decorated chlorogenic acid silver nanoparticles (AgNPs-CGA-BSA) and the studies undertaken to verify their plausible antioxidant and antineoplastic effects. High-resolution transmission electron microscopy (HR-TEM), dynamic light scattering, X-ray diffraction, and Fourier transform infrared analyses depict an average mean particle size of ∼96 nm, spherical morphology, and nanocrystalline structure of AgNPs-CGA-BSA. DPPH scavenging and inhibition of lipid peroxidation signify the noticeable in vitro antioxidant potential of the nanoparticles. The in vitro experimental results demonstrate that AgNPs-CGA-BSA shows significant cytotoxicity to Dalton's lymphoma ascites (DLA) cells and generates an enhanced intracellular reactive oxygen species and oxidized glutathione (GSSG) and reduced glutathione (GSH) in DLA cells. Furthermore, mechanism investigation divulges the pivotal role of the downregulated expression of superoxide dismutase (SOD) and catalase (CAT), and these ultimately lead to apoptotic chromatin condensation in AgNPs-CGA-BSA-treated DLA cells. In addition, in vivo experiments reveal an excellent decrease in tumor cell count, an increase in serum GSH and CAT, SOD, and glutathione peroxidase activities, and a decrease in the malondialdehyde (MDA) level in DLA-bearing mice after AgNPs-CGA-BSA treatment. These findings suggest that the newly synthesized biogenic green silver nanoparticles have remarkable in vitro antioxidant and antineoplastic efficacy that triggers cytotoxicity, oxidative stress, and chromatin condensation in DLA cells and in vivo anticancer efficacy that enhances the host antioxidant status, and these might open a new path in T-cell lymphoma therapy.

Non-medicinal parts of safflower (bud and stem) mediated sustainable green synthesis of silver nanoparticles under ultrasonication: optimization, characterization, antioxidant, antibacterial and anticancer potential

The flower of safflower is widely used in Chinese herbal preparations and the non-medicinal parts have been applied to develop a sustainable green method, where AgNPs were generated using a mixture of leaf and stem after 12 h of incubation in the dark. In this study, we intend to improve the efficiency of the reduction reaction and optimize this green method by selecting other non-medicinal parts, such as the bud and the pure stem, evaluating the biosynthesis parameters and harnessing the assistance of ultrasonication. Visual observation and UV-vis spectroscopy confirmed that both safflower stem (SS) and bud (SB) mediated AgNPs (SS-AgNPs and SB-AgNPs, respectively) could be produced rapidly over time under ultrasonication. An alkaline solution could accelerate the formation of SS-AgNPs and SB-AgNPs with greater surface loads. SS-AgNPs and SB-AgNPs of small size could be obtained at pH 8.0 and 10.0, respectively. Large concentrations of SS and SB extract are also beneficial for forming AgNPs of small size. It is in acid and neutral solutions that monodispersed SS-AgNPs and SB-AgNPs can be generated. Characterization of selectively synthesized SS-AgNPs and SB-AgNPs demonstrated their spherical shape with the actual size below 30 nm covered by anions. Both SS-AgNPs and SB-AgNPs exhibited potent antioxidant and antibacterial activity. The MIC values of SS-AgNPs for S. aureus and E. coli were 12.5 and 25.0 μg mL^-1, respectively, slightly superior to SB-AgNPs. In an in vitro anticancer assay, both kinds of AgNPs show potent toxicity action against the SW620 cell line with IC₅₀ values of 5.4 and 10.6 μg mL^-1, respectively. However, only SS-AgNPs reveal an inhibitory action against the HeLa cell line, where the IC₅₀ is found to be 26.8 μg mL^-1. These results provide experimental proof that the assistance of ultrasonication and adjusting the process parameters are efficient methods for promoting the reduction reaction, and both SS and SB mediated AgNPs could serve as a promising antioxidant, antibacterial and anticancer agents.