Green synthesis of silver nanoparticles from Stachys byzantina K. Koch: characterization, antioxidant, antibacterial, and cytotoxic activity

Silver Nanoparticles Encapped by Dihydromyricetin: Optimization of Green Synthesis, Characterization, Toxicity, and Anti-MRSA Infection Activities for Zebrafish (Danio rerio)

To achieve the environmentally friendly and rapid green synthesis of efficient and stable AgNPs for drug-resistant bacterial infection, this study optimized the green synthesis process of silver nanoparticles (AgNPs) using Dihydromyricetin (DMY). Then, we assessed the impact of AgNPs on zebrafish embryo development, as well as their therapeutic efficacy on zebrafish infected with Methicillin-resistant Staphylococcus aureus (MRSA). Transmission electron microscopy (TEM) and dynamic light-scattering (DLS) analyses revealed that AgNPs possessed an average size of 23.6 nm, a polymer dispersity index (PDI) of 0.197 ± 0.0196, and a zeta potential of -18.1 ± 1.18 mV. Compared to other published green synthesis products, the optimized DMY-AgNPs exhibited smaller sizes, narrower size distributions, and enhanced stability. Furthermore, the minimum concentration of DMY-AgNPs required to affect zebrafish hatching and survival was determined to be 25.0 μg/mL, indicating the low toxicity of DMY-AgNPs. Following a 5-day feeding regimen with DMY-AgNP-containing food, significant improvements were observed in the recovery of the gills, intestines, and livers in MRSA-infected zebrafish. These results suggested that optimized DMY-AgNPs hold promise for application in aquacultures and offer potential for further clinical use against drug-resistant bacteria.

Evaluating the Effect of pH, Temperature and Concentration on Antioxidant and Antibacterial Potential of Spectroscopically, Spectrophotometrically and Microscopically Characterized Mentha Spicata Capped Silver Nanoparticles

The use of traditional plants has been tremendously increased due to their higher biological impact, minimal side effects, and comparatively low cost. Moreover, the emergence of antibacterial resistance is also shifting the scientific community to reconsider herbal remedies which provide relatively safer, cheap and biologically tolerable solutions. The present research was designed to fabricate the Mentha spicata conjugated silver nanoparticles (Me-AgNPs). Furthermore, the assessment of the bactericidal potential of Me-AgNPs against various bacterial strains was another motive behind this study. Fabricated NPs were characterized with the help of the UV-Visible spectrophotometric analysis, Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). Me-AgNPs showed a significant zone of inhibition (23 ± 0.2 mm) at 8 mg/mL against Staphylococcus aureus and a 4.0 ± 0.2 mm zone of growth inhibition at 2 mg/mL against Aeromonas veronii. The stability of Me-AgNPs was assessed at various pH (4, 7 and 11) and temperatures (25 °C, 4 °C, 37 °C, 75 °C). The significant zones of inhibition (11.3 ± 0.3 mm, 8.3 ± 0.3mm, 14.3 ± 0.3 mm, and 7.6 ± 0.2 mm) were observed at pH 11 against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Klebsiella pneumoniae, respectively. Growth inhibition zones (14.0 ± 0.5 mm and 13.0 ± 0.5 mm) were also determined against B. subtilis and S. aureus at 25 °C. DPPH bioassay was conducted to find the antioxidant properties of Me-AgNPs. The highest (38.66 ± 0.2%) free radical scavenging activity was shown by Me-AgNPs at 4 mg/mL. Present study results concluded that biogenic Me-AgNPs have bactericidal as well as anti-oxidative potential. Moreover, these green synthesized Me-AgNPs could maintain their potency and stability at a wide range of pH and temperature.

Process optimization for green synthesis of silver nanoparticles using Rubus discolor leaves extract and its biological activities against multi-drug resistant bacteria and cancer cells

Multi-drug resistant (MDR) bacteria are considered a serious public health threat. Also, increasing rate of resistance to anticancer drugs, as well as their toxicity, is another point of concern. Therefore, the new antibacterial and anticancer agents are always needed. The synthesizing silver nanoparticles (AgNPs) using medicinal plants, is an effective approach for developing novel antibacterial and anticancer agents. Rubus discolor, a native species of the Caucasus region, produces leaves that are typically discarded as a by-product of raspberry production. The present study has focused on optimizing the green synthesis of AgNPs using R. discolor leaves extract through response surface methodology. The optimal values for AgNPs synthesis were an AgNO3 concentration of 7.11 mM, a time of 17.83 h, a temperature of 56.51 °C, and an extract percentage of 29.22. The production of AgNPs was confirmed using UV-visible spectroscopy (λmax at 456.01 nm). TEM analysis revealed well-dispersed AgNPs (an average size of 37 nm). The XRD analysis confirmed the crystalline structure. The EDX detected a strong peak at 3 keV corresponded to Ag. The zeta potential value (- 44.2 mV) indicated the stability of nanoparticles. FT-IR spectra showed the presence of various functional groups from plant compounds, which play an important role in the capping and bio-reduction processes. The AgNPs revealed impressive antibacterial activities against MDR Escherichia coli and Pseudomonas aeruginosa (MIC ranging from 0.93 to 3.75 mg ml-1). The phytochemical analysis indicated the presence of phenolics, tannins, and flavonoids on the surface of AgNPs. They also showed significant cytotoxic effects on A431, MCF-7, and HepG2 cells (IC50 values ranging from 11 to 49.1 µg ml-l).

Chitosan-based topical formulation integrated with green-synthesized silver nanoparticles utilizing Camellia sinensis leaf extracts: A promising approach for managing infected wounds

This study explores the eco-friendly biosynthesis of silver nanoparticles (AgNPs) utilizing Camellia sinensis leaf extract. We assess their antioxidant and antibacterial properties. Furthermore, we impregnated AgNPs into 2 % chitosan (CHS) gel and assessed their wound-healing potential in Escherichia coli and Staphylococcus aureus infected wounds. Optimized AgNPs demonstrated a mean particle size of 36.90 ± 1.22 nm and a PDI of 0.049 ± 0.001. Green-synthesized AgNPs exhibited enhanced free radical inhibition (IC50: 31.45 μg/mL, 34.01 μg/mL, 27.40 μg/mL) compared to leaf extract (IC50: 52.67 μg/mL, 59.64 μg/mL, 97.50 μg/mL) in DPPH, hydrogen peroxide, and nitric oxide free radical scavenging assays, respectively. The MIC/MBC values of AgNPs against E. coli and S. aureus were 5 ppm/ 7.5 ppm and 10 ppm/ 15 ppm, respectively. Furthermore, our study showed that green-synthesized AgNPs at MIC significantly reduced the biofilm production of E. coli (70.37 %) and S. aureus (67.40 %). The CHS/AgNPs gel exhibited potent wound healing activities, comparable to a commercial cream with the re-epithelialization period of 8.16 ± 0.75. Histological analysis demonstrated enhanced skin regeneration with a thicker epidermal layer, well-defined papillary dermal structure, and organized collagen fibers. In summary, these findings hold promise for addressing bacterial infections, particularly those associated with biofilms-related wound infections.

Dandelion flower-fabricated Ag nanoparticles versus synthetic ones with characterization and determination of photocatalytic, antioxidant, antibacterial, and α-glucosidase inhibitory activities

In the present work, Silver nanoparticles (AgNPs) were fabricated through the dandelion flower hydroalcoholic extract, and their properties were characterized by FTIR, XRD, UV visible, SEM, and EDX. The results demonstrated that the average diameter of the green fabricated AgNPs is 45-55 nm (G-AgNPs). The antioxidant, antimicrobial, antidiabetic, and photocatalytic properties of G-AgNPs were compared with two commercially available different diameter sizes (20 and 80-100 nm) of AgNPs (C-AgNPs1- and C-AgNPs2, respectively). The sample's capacity for antioxidants was evaluated by DPPH free radical scavenging method. The consequences showed that G-AgNPs have higher radical scavenging activity (47.8%) than C-AgNPs2 (39.49%) and C-AgNPs1 (33.91%). To investigate the photocatalytic property, methylene blue dye was used. The results displayed that G-AgNPs is an effective photo-catalyst compared to C-AgNPs2 and C-AgNPs1, which respectively have an inhibition potential of 75.22, 51.94, and 56.65%. Also, the antimicrobial capacity of nanoparticles was assayed against, the gram-negative Escherichia coli and gram-positive Staphylococcus aureus bacteria. The results indicated that G-AgNPs could effectively inhibit the growth of both bacteria, compared to C-AgNPs1 and C-AgNPs2. Finally, G-AgNPs exhibited a considerable α-glucosidase enzyme inhibitory effect (88.37%) in comparison with C-AgNPs1 (61.7%) and C-AgNPs2 (50.5%).

Chamaecyparis lawsoniana Leaf Essential Oil as a Potential Anticancer Agent: Experimental and Computational Studies

Cancer remains one of the leading causes of death worldwide, affected by several factors including oxidative stress; and although conventional synthetic medicines have been used to treat cancer, they often result in various side effects. Consequently, there is a growing need for newer, safer and more effective alternatives, such as natural plant products. Essential oils (EOs) are one such alternative, offering a wide range of bioactivities, including antibacterial, antiviral, antioxidant, and anticancer properties. Accordingly, the objective of the present study was to investigate the chemical composition, as well as the antioxidant and anticancer properties of the leaf essential oil of Chamaecyparis lawsoniana (CLLEO) belonging to the Cupressaceae family. Totally, 59 constituents were identified by gas chromatography-mass spectrometry (GC-MS) analysis. cis-Abienol, trans-ferruginol, α-cadinol, δ-muurolene and α-pinene were the major components. The in vitro cytotoxicity study against human breast (MCF-7), colon (HCT-116), lung (A-549), hepatocellular (HepG-2) carcinoma cells using MTT assay indicated a promising cytotoxic activity against all the tested cancer cells, particularly HepG-2, with significant selectivity indices. CLLEO exhibited weak antioxidant activity according to the DPPH, ABTS and FRAP assays. In silico docking of these constituents against the epidermal growth factor receptor (EGFR), the myeloid cell leukemia-1 (Mcl-1) and caspase-8 using Molecular Operating Environment (MOE) software demonstrated good binding affinities of the components with the active site of these targets. These findings suggested using CLLEO, or its individual components, as a potentially viable therapeutic option for managing cancerous conditions.

Green synthesis of silver nanoparticles based on the Raphanus sativus leaf aqueous extract and their toxicological/microbiological activities

Silver nanoparticles (AgNPs) have several uses. Many scientists are working on producing AgNPs from plant extracts for use as biomedicines against drug-resistant bacteria and malignant cell lines. In the current study, plant-based AgNPs were synthesized using Raphanus sativus L. (RS) leaf aqua extract. Different concentrations of AgNO₃ were used to optimize the synthesis process of RS-AgNPs from the aqueous leaf extract. Energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscope (AFM), and UV-vis spectroscopy were used to analyze the generated materials. Furthermore, to evaluate the biological properties of the obtained materials, Bacillus subtilis (B. subtilis), Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Candida albicans (C. albicans) pathogen strains were used for the minimum inhibitory concentration (MIC) assays. Subsequently, healthy cell lines (human dermal fibroblast (HDF)) and cancerous cell lines (glioma/U118, Ovarian/Skov-3, and colorectal adenocarcinoma/CaCo-2) were engaged to determine the cytotoxic effects of the synthesized NPs. The cytotoxic and anti-pathogenic potential of AgNPs synthesized by the proposed green approach was investigated. The results were encouraging compared to the standards and other controls. Plant-based AgNPs were found to be potential therapeutic agents against the human colon cancer cell (CaCo-2) and showed strong inhibitory activity on Candida albicans and Staphylococcus aureus growth. The RS-AgNPs generated have highly effective antimicrobial properties against pathogenic bacteria. Our findings also show that green RS-AgNPs are more cytotoxic against cancerous cell lines than normal cell lines. Synthesized nanoparticles with desirable morphology and ease of preparation are thought to be promising materials for antimicrobial, cytotoxic, and catalytic applications.

Cytotoxic effects of extracts obtained from plants of the Oleaceae family: bio-guided isolation and molecular docking of new secoiridoids from Jasminum humile

CONTEXT

Traditionally, Oleaceae plants are used to treat many diseases, such as rheumatism, hypercholesterolaemia, or ulcers.

OBJECTIVES

To investigate the cytotoxic potential of Jasminum humile L., Jasminum grandiflorum L., and Olea europaea L. (Oleaceae) extracts against selected human cancer cells lines, followed by a phytochemical investigation of the most potent one.

MATERIALS AND METHODS

The 95% ethanol extracts of aerial parts of three oleaceous plants were examined for their cytotoxicity against HepG-2, MCF-7, and THP-1 cell lines using MTT assay and doxorubicin (positive control). J. humile was bio-selected and submitted to bio-guided fractionation. Chromatographic workup of ethyl acetate and n-butanol fractions afforded two new compounds; 1-methoxyjasmigenin (1) and 1-methyl-9-aldojasmigenin (2), along with five known ones (3-7). Structures were unambiguously elucidated using 1D/2D NMR and ESI-HRMS. Isolated compounds were assessed for their anti-proliferative potential, and both selectivity index and statistical significance were determined. Molecular docking was conducted against the Mcl-1 receptor using (AZD5991) as a standard.

RESULTS

Jasmoside (5) was the most potent anticancer compound showing IC₅₀ values of 66.47, 41.32, and 27.59 µg/mL against HepG-2, MCF-7, and THP-1 cell lines, respectively. Moreover, isojasminin (4) exhibited IC₅₀ values of 33.49, 43.12, and 51.07 µg/mL against the same cell lines, respectively. Interestingly, 5 exhibited the highest selectivity index towards MCF-7 and THP-1, even greater than doxorubicin. Molecular docking results were in full agreement with the MTT assay and the proposed SAR.

CONCLUSION

In this study, two new compounds were purified. The biological activity highlighted jasmoside (5) as a lead anticancer drug for further future investigation.

Cichorium intybus bio-callus synthesized silver nanoparticles: A promising antioxidant, antibacterial and anticancer compound

Cichorium intybus, commonly called chicory, has been widely used as a coffee substitute. It display a wide range of natural compounds and medicinally uses in treatment of gastrointestinal disorders. This study synthesized silver nanoparticles (Ci-AgNPs) using C. intybus leaf-derived callus extract to evaluate phytochemical content, antibacterial, antioxidant and anti-proliferative activities against human breast cancer cells (MDA-MB231). The optimal shape, size and stability of Ci-AgNPs was confirmed using UV-visible spectrophotometry, FESEM, EDX, XRD, DLS, Zeta potential, FTIR and sp-ICP-MS studies. The antibacterial activity of Ci-AgNPs was assessed using disk diffusion method against Staphylococcus aureus and Escherichia coli, and they displayed distinct zones of inhibition. Colorimetric phytochemical analysis of Ci-AgNPs revealed their higher total phenolic (TP) and total flavonoid (TF) content. Ci-AgNPs also indicated a high level of antioxidant activity using FRAP and DPPH assays. The Ci-AgNPs were investigated for their anticancer activities on the cancerous MDA-MB231 cells viability and apoptosis using MTT and flow cytometry, respectively. Ci-AgNPs showed dose dependent cytotoxicity against MDA-MB231 cells with IC50 value of 187.6 μg/mL at 48 h through induction of apoptosis. The biocompatibility test showed that Ci-AgNPs induced neglectable cytotoxicity (lower than 3 %) toward human erythrocytes. This is the first study that reports the bio-callus mediated synthesis of silver nanoparticle using C. intybus callus extract which provided a promising anticancer activity against human breast cancer MDA-MB231 cells and therefore could be used as an alternative and interesting benign strategy for biosynthesis of silver nanoparticles useful in cancer therapy.

Preparation and characterization of biogenic silver nanoparticles using Strobilanthes cordifolia (Vahl) J.R.I.Wood leaves and its Biological applications

In the present study aqueous leaf extract of Strobilanthes cordifolia J.R.I.Wood was combined with silver nitrate to synthesis silver nanoparticles (AgNPs).The AgNPs was Characterized using visible spectroscopy (UV), X-ray diffraction(XRD), fourier transform infrared spectrophotometer (FTIR), scanning electron microscope (SEM), energy dispersive X-ray (EDaX), particle size analysis and transmission electron microscope (TEM).The UV spectrum absorption peak occurred at 438nm. The FTIR analysis of the AgNPs indicated the presence of functional groups such as aldehyde, alkenes and carboxylic acids.The crystalline structure of AgNPs was confirmed by XRD. The AgNPs have a spherical shape according to SEM. The AgNPs components composition was confirmed by EDaX.The particle size distribution of AgNPs is monodispersion in the range at 42.54nm.TEM demonstrated that the AgNPs size to be between 11.35-34.90nm.The AgNPs exhibited good antibacterial against Escherichia coli and Staphylococcus aureus. The antioxidant activity of the AgNPs was represented by increased DPPH, ABTS and H₂ O₂ activities.The antidiabetic activity of the AgNPs was indicated by the inhibition of α-amylase and α-glycosidase and anti-inflammatory highest albumin denaturation and HRBC membrane stabilization properties. Further, the AgNPs also significantly inhibited the MCF-7 cell lines. These results clearly suggest that the synthesized AgNPs using S. cordifolia leaves could have several potential biomedical applications. This article is protected by copyright. All rights reserved.

Nanoemulsions of Jasminum humile L. and Jasminum grandiflorum L. Essential Oils: An Approach to Enhance Their Cytotoxic and Antiviral Effects

Unprecedented nanoemulsion formulations (NE) of Jasminum humile and Jasminum grandiflorum essential oils (EO) were prepared, and examined for their cytotoxic and antiviral activities. NE characterization and stability examination tests were performed to ensure formula stability. The antiviral activity was determined against hepatitis A (HAV) and herpes simplex type-1 (HSV-1) viruses using MTT assay, while the cytotoxic potential was determined against liver (HepG-2), breast (MCF-7), leukemia (THP-1) cancer cell lines and normal Vero cells. Statistical significance was determined in comparison with doxorubicin as cytotoxic and acyclovir as antiviral standard drugs. GC-MS analysis indicated twenty four compounds in the EO of J. humile and seventeen compounds in the EO of J. grandiflorum. Biological investigations of pure EOs revealed weak cytotoxic and antiviral effects. Nevertheless, their NE formulations exhibited high biological value as cytotoxic and antiviral agents. NE formulations also showed feasible selectivity index for the viral-infected and cancer cells (especially HepG-2) than normal Vero cells. Both nanoemulsions showed lower IC₅₀ than standard doxorubicin against HepG-2 (26.65 and 22.58 vs. 33.96 μg/mL) and MCF-7 (36.09 and 36.19 vs. 52.73 μg/mL), respectively. The study results showed the dramatic effect of nanoemulsion preparation on the biological activity of EOs and other liposoluble phytopharmaceuticals.

Phytochemical analysis, antioxidant, cytotoxic, and antimicrobial activities of golden chamomile (Matricaria aurea (Loefl.) Schultz Bip)

Matricaria aurea (Loefl.) Schultz Bip. (Asteraceae), known as golden chamomile, has been traditionally used for the treatment of various diseases. In this study, total phenolic, flavonoid, and tannin contents of total extract and different fractions of this plant were determined. The antioxidant, cytotoxic, and antimicrobial activities were also evaluated. Moreover, the phenolic profiles of selected fractions were determined by HPLC and LC-MS/MS analysis. Results demonstrated total phenolic contents of 37.8-57.2 mg GAE/g and total flavonoid contents of 3.0-111.2 mg QE/g. The ethyl acetate and methanol fractions (EF and MF) had the highest concentrations of phenolic, tannin, and flavonoid compounds. In both DPPH radical scavenging assay and phosphomolybdenum reduction assay, EF showed the best antioxidant activity, followed by MF. EF and MF indicated also the best antibacterial activities against Bacillus subtilis (MIC 1.56 and 12.5 mg ml^-1) and Staphylococcus aureus (MIC 0.78 and 12.5 mg ml^-1). Hexane fraction (HF) had no antibacterial effect. None of the samples had antifungal effect. MTT (3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay revealed for EF and HF the highest antiproliferative activities (IC₅₀ values ranged from 111.8 to 294.6 μg ml^-1). The presence of chlorogenic acid, ferulic acid, and luteolin-7-O-glucoside in MF, and p-coumaric acid in EF was confirmed and quantified.