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1.
The biosynthesis of metallic nanoparticles is on a sharp rise as they have growing applications in environmental and biomedical sciences. This study reports an eco-friendly and cost-effective methodology for synthesizing biogenic silver nanoparticles (AgNPs) using the extract of Medicago sativa (M. sativa) cultivated in South Khorasan. The parameters used in the synthesis process were optimized to obtain uniformly distributed AgNPs in suitable sizes. The morphological, structural, and bonding characteristics of M. sativa extract-based AgNPs (MSE-AgNPs) were explored using FTIR, FESEM, EDS, TEM, XRD, UV–Vis, and DLS techniques. UV–Vis spectroscopy confirmed the formation of MSE-AgNPs by observing the typical surface plasmon resonance (SPR) peak at 419 nm. XRD, FESEM, TEM, and DLS analyses confirmed the formation of face-centered cubic (fcc) crystalline structure, spherical/elliptical morphology, the average particle size of 15–35 nm, and highly stable MSE-AgNPs. Green synthesized MSE-AgNPs indicated a significant antioxidant activity (78%) compared to M. sativa extract (32%). As such, the synthesized MSE-AgNPs revealed a potential antioxidant activity towards the DPPH radicals. The biologically synthesized MSE-AgNPs exhibited highly potential antibacterial and antifungal activities against Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Staphylococcus epidermidis, Enterococcus faecalis, Staphylococcus aureus, and Candida albicans with the minimum inhibitory concentration (MIC) values of 62.5, 125, 125, 1000, 125, 1000, and 31.25 µg/mL, respectively. In vitro cytotoxicity of the MSE-AgNPs against human fibroblast (HF) cells indicated a dose–response activity (with IC50 value of 18 µg/mL). Moreover, the AgNPs revealed efficient photocatalytic degradation of thymol blue (TB) as an anionic dye and malachite green (MG) as a cationic dye under sunlight and UV irradiations. Up to 94.37% and 90.12% degradation rates were obtained for MG and TB within only 100 min of UV irradiation. These observations signify that synthesized MSE-AgNPs can have great potential for biological and environmental applications.  相似文献   

2.
Highly selective label free colorimetric sensor based on AgNPs stabilized by phenolic chelating ligand, N,N′-bis(2-hydroxybenzyl)-1,2-diaminobenzene (1), for NO2 anions has been developed. Addition of NO2 showed selective decolourisation of brownish yellow colour of 1-AgNPs with the detection limit of 10−7 M. Absorption studies showed the complete disappearance of 1-AgNPs peak at 426 nm due to the conversion of AgNPs to silver ions. The presence silver ions were confirmed by white precipitates of AgCl formation with NaCl. The interference studies confirmed the high selectivity of NO2 sensing in presence of anions as well as cations by 1-AgNPs. A linear relationship was observed between the change of absorption and concentration of NO2. The present approach could be performed at room temperature and ambient conditions. The practical applications of 1-AgNPs for selective sensing of NO2 in different water samples such as ground, river, pond and tap water have also been demonstrated.  相似文献   

3.
In the present study, we demonstrate the green synthesis of silver nanoparticles using Sophora pachycarpa extract (S. pachycarpa; SPE) as capping, reducing, and stabilizing agents. The biosynthesized silver nanoparticles (SPE-AgNPs) were tested for catalytic, antibacterial, antifungal, antioxidant, and anti-cancer activities. The affecting parameters (the concentration of silver nitrate, the temperature of the reaction, and time of reaction) on the synthesis process were optimized. The biosynthesized SPE-AgNPs were studied by X-Ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS), energy-dispersive X-ray spectroscopy (EDS) and Fourier-transform infrared spectroscopy (FT-IR). The FESEM and TEM results revealed spherical and oval-like morphology with sizes ranging from 30 to 40 nm. Photocatalytic performance experiments of SPE-AgNPs were determined by the rapid degradation of the eriochrome black T (EBT) and methylene blue (MB) under sunlight and UV irradiations. The results showed that SPE-AgNPs degraded more than 90% and 80% of both dyes under UV and sunlight irradiations, respectively. In addition, the SPE-AgNPs exhibited good antibacterial and antifungal properties against S. aureus, S. epidermidis, P. aeruginosa, E. coli, K. pneumoniae, E. faecalis, and C. albicans with MIC values of 6.25, 6.25, 0.78, 0.39, 0.78, 1.56 and 0.78 µg/ml. The green synthesized SPE-AgNPs were found to inhibit the activity of DPPH free radicals efficiently. Eventually, the SPE-AgNPs exhibited significant in vitro cytotoxicity against K562 tumor cell line (IC50 = 19.5 µg/ml). All these studies indicated that AgNPs synthesized using S. pachycarpa extract have applications in the environmental and biomedical fields.  相似文献   

4.
A combined osmotic pressure and cake filtration model for crossflow nanofiltration of natural organic matter (NOM) was developed and successfully used to determine model parameters (i.e. permeability reduction factor (η) and specific cake resistance (αcake)) for salt concentrations, NOM concentrations, and ionic strength of salt species (Na+ and Ca++). In the absence of NOM, with increasing salt concentration from 0.004 to 0.1 M, permeability reduction factor (η)) decreased from 0.99 to 0.72 and 0.94 to 0.44 for monovalent cation (Na+) and divalent cation (Ca++), respectively. This reduced membrane permeability was due to salt concentrations and salt species. In the presence of NOM, specific cake resistance tended to increase with increasing NOM concentration and ionic strength in the range of 0.85 × 1015–3.66 × 1015 m kg−1. Solutions containing divalent cation exhibited higher normalized flux decline (Jv/Jvo = 0.685–0.632) and specific cake resistance (αcake = 2.89 × 1015–6.24 × 1015 m kg−1) than those containing monovalent cation, indicating a highly compacted NOM accumulation, thus increased permeate flow resistance during NF filtration experiments. After membrane cleaning, divalent cation exhibited lower water flux recovery than monovalent cation, suggesting higher non-recoverable (Rnon-rec) resistance than monovalent cation.  相似文献   

5.
Electroactive biomaterials are fascinating for tissue engineering applications because of their ability to deliver electrical stimulation directly to cells, tissue, and organs. One particularly attractive conductive filler for electroactive biomaterials is silver nanoparticles (AgNPs) because of their high conductivity, antibacterial activity, and ability to promote bone healing. However, production of AgNPs involves a toxic reducing agent which would inhibit biological scaffold performance. This work explores facile and green synthesis of AgNPs using extract of Cilembu sweet potato and studies the effect of baking and precursor concentrations (1, 10 and 100 mM) on AgNPs’ properties. Transmission electron microscope (TEM) results revealed that the smallest particle size of AgNPs (9.95 ± 3.69 nm) with nodular morphology was obtained by utilization of baked extract and ten mM AgNO3. Polycaprolactone (PCL)/AgNPs scaffolds exhibited several enhancements compared to PCL scaffolds. Compressive strength was six times greater (3.88 ± 0.42 MPa), more hydrophilic (contact angle of 76.8 ± 1.7°), conductive (2.3 ± 0.5 × 10−3 S/cm) and exhibited anti-bacterial properties against Staphylococcus aureus ATCC3658 (99.5% reduction of surviving bacteria). Despite the promising results, further investigation on biological assessment is required to obtain comprehensive study of this scaffold. This green synthesis approach together with the use of 3D printing opens a new route to manufacture AgNPs-based electroactive with improved anti-bacterial properties without utilization of any toxic organic solvents.  相似文献   

6.
Senecio nutans Sch. Bip. and its constituents are reported to have antihypertensive effects. We isolated metabolite–1, a natural compound from S. nutans (4-hydroxy-3-(isopenten-2-yl)-acetophenone), and synthesized novel oxime – 1 (4-hydroxy-3-(isopenten-2-yl)-acetophenoxime) to evaluate their effect on vascular reactivity. Compounds were purified (metabolite–1) or synthetized (oxime–1) and characterized using IR and NMR spectroscopy and Heteronuclear Multiple Quantum Coherence (HMQC). Using pharmacological agents such as phenylephrine (PE) and KCl (enhancing contraction), acetylcholine (ACh), L-NAME (nitric oxide (NO) and endothelial function), Bay K8644-induced CaV1.2 channel (calcium channel modulator), and isolated aortic rings in an organ bath setup, the possible mechanisms of vascular action were determined. Pre-incubation of aortic rings with 10−5 M oxime–1 significantly (p < 0.001) decreased the contractile response to 30 mM KCl. EC50 to KCl significantly (p < 0.01) increased in the presence of oxime–1 (37.72 ± 2.10 mM) compared to that obtained under control conditions (22.37 ± 1.40 mM). Oxime–1 significantly reduced (p < 0.001) the contractile response to different concentrations of PE (10−7 to 10−5 M) by a mechanism that decreases Cav1.2-mediated Ca2+ influx from the extracellular space and reduces Ca2+ release from intracellular stores. At a submaximal concentration (10−5 M), oxime–1 caused a significant relaxation in rat aorta even without vascular endothelium or after pre-incubate the tissue with L-NAME. Oxime–1 decreases the contractile response to PE by blunting the release of Ca2+ from intracellular stores and blocking of Ca2+ influx by channels. Metabolite–1 reduces the contractile response to KCl, apparently by reducing the plasma membrane depolarization and Ca2+ influx from the extracellular space. These acetophenone derivates from S. nutans (metabolite–1 and oxime–1) cause vasorelaxation through pathways involving an increase of the endothelial NO generation or a higher bioavailability, further highlighting that structural modification of naturally occurring metabolites can enhance their intended pharmacological functions.  相似文献   

7.
This study deals with selective separation of mono- and divalent cations from aqueous salt solutions using polymeric films based on polyethylene (PE) and polyamide6 (PA6), and two different commercial nanofiltration (NF) membranes. The diffusion rates (D) of ions (Na+ and Ca2+), separation factors (α) and ion rejections (R) of the films and NF membranes are examined comparatively as well as their surface morphology and hydrophilicity. It is observed that the diffusion rates of Na+ are in the range of 0.7–1.8 × 10−8cm2 .s−1 in the decreasing order of PE > NF90 > NF270 > PA6 while Ca2+ shows diffusion rates of 7.4–18.4 × 10−8 cm2 .s−1 in the increasing order of NF270 > NF90 ≈ PA6 > PE. Rejection values of the polymeric films and NF membranes against to Na+ and Ca2+ vary between 90% and 99.6%.The highest α(Ca2+/Na+) is found to be 20 for PA6 film. D, α, and R value of both polymeric films and NF membranes are strongly affected by the existence of osmosis during diffusion-dialysis and the sizes of hydrated sodiu and calcium ions. In conclusion, the film based on PA6 may be a good alternative for selective separation of mono- an divalent cations.  相似文献   

8.
Cannabis sativa L. (hemp) is a plant used in the textile industry and green building material industry, as well as for the phytoremediation of soil, medical treatments, and supplementary food products. The synergistic effect of terpenes, flavonoids, and cannabinoids in hemp extracts may mediate the biogenic synthesis of metal nanoparticles. In this study, the chemical composition of aqueous leaf extracts of three varieties of Romanian hemp (two monoecious, and one dioecious) have been determined by Fourier-Transformed Infrared spectroscopy (FT-IR), high-performance liquid chromatography, and mass spectrometry (UHPLC-DAD-MS). Then, their capability to mediate the green synthesis of silver nanoparticles (AgNPs) and their pottential antibacterial applications were evaluated. The average antioxidant capacity of the extracts had 18.4 ± 3.9% inhibition determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 78.2 ± 4.1% determined by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS™) assays. The total polyphenolic content of the extracts was 1642 ± 32 mg gallic acid equivalent (GAE) L−1. After this, these extracts were reacted with an aqueous solution of AgNO3 resulting in AgNPs, which were characterized by UV−VIS spectroscopy, FT-IR, scanning electron microscopy (SEM-EDX), and dynamic light scattering (DLS). The results demonstrated obtaining spherical, stable AgNPs with a diameter of less than 69 nm and an absorbance peak at 435 nm. The mixture of extracts and AgNPs showed a superior antioxidant capacity of 2.3 ± 0.4% inhibition determined by the DPPH assay, 88.5 ± 0.9% inhibition as determined by the ABTS•+ assay, and a good antibacterial activity against several human pathogens: Escherichia coli, Klebsiella pneumoniae, Pseudomonas fluorescens, and Staphylococcus aureus.  相似文献   

9.
Synthetic and natural ionophores have been developed to catalyze ion transport and have been shown to exhibit a variety of biological effects. We synthesized 24 aza- and diaza-crown ethers containing adamantyl, adamantylalkyl, aminomethylbenzoyl, and ε-aminocaproyl substituents and analyzed their biological effects in vitro. Ten of the compounds (8, 10–17, and 21) increased intracellular calcium ([Ca2+]i) in human neutrophils, with the most potent being compound 15 (N,N’-bis[2-(1-adamantyl)acetyl]-4,10-diaza-15-crown-5), suggesting that these compounds could alter normal neutrophil [Ca2+]i flux. Indeed, a number of these compounds (i.e., 8, 10–17, and 21) inhibited [Ca2+]i flux in human neutrophils activated by N-formyl peptide (fMLF). Some of these compounds also inhibited chemotactic peptide-induced [Ca2+]i flux in HL60 cells transfected with N-formyl peptide receptor 1 or 2 (FPR1 or FPR2). In addition, several of the active compounds inhibited neutrophil reactive oxygen species production induced by phorbol 12-myristate 13-acetate (PMA) and neutrophil chemotaxis toward fMLF, as both of these processes are highly dependent on regulated [Ca2+]i flux. Quantum chemical calculations were performed on five structure-related diaza-crown ethers and their complexes with Ca2+, Na+, and K+ to obtain a set of molecular electronic properties and to correlate these properties with biological activity. According to density-functional theory (DFT) modeling, Ca2+ ions were more effectively bound by these compounds versus Na+ and K+. The DFT-optimized structures of the ligand-Ca2+ complexes and quantitative structure-activity relationship (QSAR) analysis showed that the carbonyl oxygen atoms of the N,N’-diacylated diaza-crown ethers participated in cation binding and could play an important role in Ca2+ transfer. Thus, our modeling experiments provide a molecular basis to explain at least part of the ionophore mechanism of biological action of aza-crown ethers.  相似文献   

10.
The present study focuses on the biological synthesis, characterization, and antibacterial activities of silver nanoparticles (AgNPs) using extracellular extracts of Aspergillus japonicus PJ01.The optimal conditions of the synthesis process were: 10 mL of extracellular extracts, 1 mL of AgNO3 (0.8 mol/L), 4 mL of NaOH solution (1.5 mol/L), 30 °C, and a reaction time of 1 min. The characterizations of AgNPs were tested by UV-visible spectrophotometry, zeta potential, scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric (TG) analyses. Fourier transform infrared spectroscopy (FTIR) analysis showed that Ag+ was reduced by the extracellular extracts, which consisted chiefly of soluble proteins and reducing sugars. In this work, AgNO3 concentration played an important role in the physicochemical properties and antibacterial properties of AgNPs. Under the AgNO3 concentration of 0.2 and 0.8 mol/L, the diameters of AgNPs were 3.8 ± 1.1 and 9.1 ± 2.9 nm, respectively. In addition, smaller-sized AgNPs showed higher antimicrobial properties, and the minimum inhibitory concentration (MIC) values against both E. coli and S. aureus were 0.32 mg/mL.  相似文献   

11.
Interleukin-1β (IL-1β), a product of the NLRP3 inflammasome, modulates cardiac contractility and diastolic function. We proposed that OLT1177® (dapansutrile), a novel NLRP3 inhibitor, could preserve contractile reserve and diastolic function after myocardial infarction (MI). We used an experimental murine model of severe ischemic cardiomyopathy through the ligation of the left coronary artery without reperfusion, and after 7 days randomly assigned mice showing large anterior MI (>4 akinetic segments), increased left ventricular (LV) dimensions ([LVEDD] > 4.4 mm), and reduced function (LV ejection fraction < 40%) to a diet that was enriched with OLT1177® admixed with the chow in the diet at 3.75 g/kg (Group 1 [n = 10]) or 7.5 g/kg (Group 2 [n = 9]), or a standard diet as the no-treatment control group (Group 3 [n = 10]) for 9 weeks. We measured the cardiac function and contractile reserve with an isoproterenol challenge, and the diastolic function with cardiac catheterization at 10 weeks following the MI surgery. When compared with the control (Group 3), the mice treated with OLT1177 (Group 1 and 2) showed significantly greater preservation of their contractile reserve (the percent increase in the left ventricular ejection fraction [LVEF] after the isoproterenol challenge was +33 ± 11% and +40 ± 6% vs. +9 ± 7% in the standard diet; p < 0.05 and p < 0.005 for Group 1 and 2, respectively) and of diastolic function measured as the lower left ventricular end-diastolic pressure (3.2 ± 0.5 mmHg or 4.5 ± 0.5 mmHg vs. 10.0 ± 1.6 mmHg; p < 0.005 and p < 0.009 respectively). No differences were noted between the resting LVEF of the MI groups. These effects were independent of the effects on the ventricular remodeling after MI. NLRP3 inflammasome inhibition with OLT1177® can preserve β-adrenergic responsiveness and prevent left ventricular diastolic dysfunction in a large non-reperfused anterior MI mouse model. OLT1177® could therefore be used to prevent the development of heart failure in patients with ischemic cardiomyopathy.  相似文献   

12.
《印度化学会志》2021,98(12):100221
Green synthesis of silver nanoparticles was accomplished using peels (rind) extract of Citrus aurantium as a reducing as well as capping agent. Biosynthesized AgNPs (silver nanoparticle) has been characterized via UV–Visible spectroscopy, XRD, SEM, EDAX, TEM and TGA. The observed UV–Vis analysis resulted in the formation of characteristic surface plasmon resonance absorption band centered at 465 ​nm. The observed XRD patterns, having hkl values (111), (200), (220) and (222), confirms the cubic crystalline structure of AgNPs. The average grain size 9.5 ​μm was observed by the SEM technique. Bio synthesized AgNPs were efficiently degrading the methylene blue dye nearly 95.35% in 98 ​h of exposure time. It also degraded acridine orange dye 87.34% and rose bengal dye 90.09% followed by 4h of continuous UV absorption. It also degrades methyl orange dye nearly 51% in 10h of solar irradiation. Synthesized AgNPs can be used as photo-catalyst for degrading toxic dyes.  相似文献   

13.
This present study evaluated and rationalized the medicinal use of the fruit part of Acacia nilotica methanolic extract. The phytochemicals were detected using gas chromatography–mass spectrometry (GC–MS) while the in vivo antidiarrheal test was done using Swiss albino mice. To determine the details of the mechanism(s) involved in the antispasmodic effect, isolated rat ileum was chosen using different ex vivo assays by maintaining a physiological environment. GC–MS results showed that A. nilotica contained pyrogallol as the major polyphenol present (64.04%) in addition to polysaccharides, polyphenol, amino acid, steroids, fatty acid esters, and triterpenoids. In the antidiarrheal experiment, A. nilotica inhibited diarrheal episodes in mice significantly (p < 0.05) by 40% protection of mice at 200 mg/kg, while 80% protection was observed at 400 mg/kg by the orally administered extract. The highest antidiarrheal effect was observed with loperamide (p < 0.01), used as a control drug. In the ex vivo experiments, A. nilotica inhibited completely in increasing concentrations (0.3 to 10 mg/mL) the carbachol (CCh; 1 µM) and high K+ (80 mM)-evoked spasms in ileum tissues at equal potencies (p > 0.05), similar to papaverine, a dual inhibitor of the phosphodiesterase enzyme (PDE) and Ca++ channels. The dual inhibitory-like effects of A. nilotica on PDE and Ca++ were further validated when A. nilotica extract (1 and 3 mg/mL)-pre-incubated ileum tissues potentiated and shifted isoprenaline relaxation curves towards lower doses (leftward), similar to papaverine, thus confirming the PDE inhibitory-like mechanism whereas its CCB-like effect of the extract was confirmed at 3 and 5 mg/mL by non-specific inhibition of CaCl2-mediated concentration response curves towards the right with suppression of the maximum peaks, similar to verapamil, used as standard CCB. Thus, this study characterized the chemical composition and provides mechanistic support for medicinal use of A. nilotica in diarrheal and hyperactive gut motility disorders.  相似文献   

14.
In women with preeclampsia (PE), endothelial cell (EC) dysfunction can lead to altered secretion of paracrine factors that induce peripheral vasoconstriction and proteinuria. This study examined the hypothesis that PE sera may directly or indirectly, through human umbilical vein ECs (HUVECs), stimulate phospholipase C-γ1-1,4,5-trisphosphate (PLC-γ1-IP3) signaling, thereby increasing protein kinase C-α (PKC-α) activity, collagen I expression and intracellular Ca2+ concentrations ([Ca2+]i) in human umbilical artery smooth muscle cells (HUASMCs). HUASMCs and HUVECs were cocultured with normal or PE sera before PLC-γ1 silencing. Increased PLC-γ1 and IP3 receptor (IP3R) phosphorylation was observed in cocultured HUASMCs stimulated with PE sera (P<0.05). In addition, PE serum significantly increased HUASMC viability and reduced their apoptosis (P<0.05); these effects were abrogated with PLC-γ1 silencing. Compared with normal sera, PE sera increased [Ca2+]i in cocultured HUASMCs (P<0.05), which was inhibited by PLC-γ1 and IP3R silencing. Finally, PE sera-induced PKC-α activity and collagen I expression was inhibited by PLC-γ1 small interfering RNA (siRNA) (P<0.05). These results suggest that vasoactive substances in the PE serum may induce deposition in the extracellular matrix through the activation of PLC-γ1, which may in turn result in thickening and hardening of the placental vascular wall, placental blood supply shortage, fetal hypoxia–ischemia and intrauterine growth retardation or intrauterine fetal death. PE sera increased [Ca2+]i and induced PKC-α activation and collagen I expression in cocultured HUASMCs via the PLC-γ1 pathway.  相似文献   

15.
The ethanolic extracts of three Equisetum species (E. pratense Ehrh., E. sylvaticum L. and E. telmateia Ehrh.) were used to reduce silver ions to silver nanoparticles (AgNPs). The synthesized AgNPs were characterized using UV-Vis spectrophotometry, Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-ray (EDX), Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS) measurements. FTIR data revealed the functional groups of biomolecules involved in AgNPs synthesis, such as O-H, C-H, C=O, C-O, and C-C. EDX spectroscopy was used to highlight the presence of silver, while DLS spectroscopy provided information on the mean diameter of AgNPs, that ranged from 74.4 to 314 nm. The negative Zeta potential values (−23.76 for Ep–AgNPs, −29.54 for Es–AgNPs and −20.72 for Et–AgNPs) indicate the stability of the obtained colloidal solution. The study also focused on establishing the photocatalytic activity of AgNPs, which is an important aspect in terms of removing organic dyes from the environment. The best photocatalytic activity was observed for AgNPs obtained from E. telmateia, which degraded malachite green in a proportion of 97.9%. The antioxidant action of the three AgNPs samples was highlighted comparatively through four tests, with the best overall antioxidant capacity being observed for AgNPs obtained using E. sylvaticum. Moreover, the biosynthesized AgNPs showed promising cytotoxic efficacy against cancerous cell line MG63, the AgNPs obtained from E. sylvaticum L. providing the best result, with a LD50 value around 1.5 mg/mL.  相似文献   

16.
This research aimed to enhance the antibacterial activity of silver nanoparticles (AgNPs) synthesized from silver nitrate (AgNO3) using aloe vera extract. It was performed by means of incorporating AgNPs on an activated carbon nanoparticle (ACNPs) under ultrasonic agitation (40 kHz, 2 × 50 watt) for 30 min in an aqueous colloidal medium. The successful AgNPs synthesis was clarified with both Ultraviolet-Visible (UV-Vis) and Fourier Transform Infrared (FTIR) spectrophotometers. The successful AgNPs–ACNPs incorporation and its particle size analysis was performed using Transmission Electron Microscope (TEM). The brown color suspension generation and UV-Vis’s spectra maximum wavelength at around 480 nm confirmed the existence of AgNPs. The particle sizes of the produced AgNPs were about 5 to 10 nm in the majority number, which collectively surrounded the aloe vera extract secondary metabolites formed core-shell like nanostructure of 8.20 ± 2.05 nm in average size, while ACNPs themselves were about 20.10 ± 1.52 nm in average size formed particles cluster, and 48.00 ± 8.37 nm in average size as stacking of other particles. The antibacterial activity of the synthesized AgNPs and AgNPs-immobilized ACNPs was 57.58% and 63.64%, respectively (for E. coli); 61.25%, and 93.49%, respectively (for S. aureus). In addition, when the AgNPs-immobilized ACNPs material was coated on the cotton and polyester fabrics, the antibacterial activity of the materials changed, becoming 19.23% (cotton; E. coli), 31.73% (polyester; E. coli), 13.36% (cotton; S. aureus), 21.15% (polyester; S. aureus).  相似文献   

17.
The combination of saccharides in the composition of a cryopreservation medium may represent a promising method for the preservation of the reproductive cells of male birds. In the current study, cryoprotective media with a combined composition of mono- and di-saccharides were developed. The degree of penetration of reducing saccharide molecules (maltose—Mal20 medium) and non-reducing disaccharide molecules (trehalose—Treh20 medium) from the cryoprotective medium into the cytosol of rooster spermatozoa was studied. LCM control media without disaccharides were used as the control. The number of maltose molecules penetrating from the outside into the cytosol of the spermatozoon was 1.06 × 104, and the number of trehalose molecules was 3.98 × 104. Using a combination of maltose and fructose, the progressive motility of frozen/thawed semen and the fertility rates of eggs were significantly higher ((p < 0.05) 40.2% and 68.5%, respectively) than when using a combination of trehalose and fructose in a cryoprotective diluent (33.4% and 62.4%, respectively). A higher rate of chromatin integrity at the level of 92.4% was obtained when using Treh20 versus 74.5% Mal20 (p < 0.05). Maltose positively affected the preservation of frozen/thawed sperm in the genital tract of hens. On the seventh day from the last insemination when using Mal20, the fertilization of eggs was 42.6% and only 27.3% when using Treh20. Despite the same molecular weight, maltose and trehalose have different physicochemical and biological properties that determine their function and effectiveness as components of cryoprotective media.  相似文献   

18.
The solubility of glibenclamide was evaluated in DMSO, NMP, 1,4-dioxane, PEG 400, Transcutol® HP, water, and aqueous mixtures (T = 293.15~323.15 K). It was then recrystallized to solvate and compressed into tablets, of which 30-day stability and dissolution was studied. It had a higher solubility in 1,4-dioxane, DMSO, NMP (Xexp = 2.30 × 103, 3.08 × 104, 2.90 × 104) at 323.15 K, its mixture (Xexp = 1.93 × 103, 1.89 × 104, 1.58 × 104) at 298.15 K, and 1,4-dioxane (w) + water (1−w) mixture ratio of w = 0.8 (Xexp = 3.74 × 103) at 323.15 K. Modified Apelblat (RMSD ≤ 0.519) and CNIBS/R-K model (RMSD ≤ 0.358) suggested good comparability with the experimental solubility. The minimum value of ΔG° vs ΔH° at 0.70 < x2 < 0.80 suggested higher solubility at that molar concentration. Based on the solubility, it was recrystallized into the solvate, which was granulated and compressed into tablets. Among the studied solvates, the tablets of glibenclamide dioxane solvate had a higher initial (95.51%) and 30-day (93.74%) dissolution compared to glibenclamide reference (28.93%). There was no stability issue even after granulation, drying, or at pH 7.4. Thus, glibenclamide dioxane solvate could be an alternative form to improve the molecule’s properties.  相似文献   

19.
Fenchone is a bicyclic monoterpene found in a variety of aromatic plants, including Foeniculum vulgare and Peumus boldus, and is used in the management of airways disorders. This study aimed to explore the bronchodilator effect of fenchone using guinea pig tracheal muscles as an ex vivo model and in silico studies. A concentration-mediated tracheal relaxant effect of fenchone was evaluated using isolated guinea pig trachea mounted in an organ bath provided with physiological conditions. Sustained contractions were achieved using low K+ (25 mM), high K+ (80 mM), and carbamylcholine (CCh; 1 µM), and fenchone inhibitory concentration–response curves (CRCs) were obtained against these contractions. Fenchone selectively inhibited with higher potency contractions evoked by low K+ compared to high K+ with resultant EC50 values of 0.62 mg/mL (0.58–0.72; n = 5) and 6.44 mg/mL (5.86–7.32; n = 5), respectively. Verapamil (VRP) inhibited both low and high K+ contractions at similar concentrations. Pre-incubation of the tracheal tissues with K+ channel blockers such as glibenclamide (Gb), 4-aminopyridine (4-AP), and tetraethylammonium (TEA) significantly shifted the inhibitory CRCs of fenchone to the right towards higher doses. Fenchone also inhibited CCh-mediated contractions at comparable potency to its effect against high K+ [6.28 mg/mL (5.88–6.42, n = 4); CCh] and [6.44 mg/mL (5.86–7.32; n = 5); high K+]. A similar pattern was obtained with papaverine (PPV), a phosphodiesterase (PDE), and Ca2+ inhibitor which inhibited both CCh and high K+ at similar concentrations [10.46 µM (9.82–11.22, n = 4); CCh] and [10.28 µM (9.18–11.36; n = 5); high K+]. However, verapamil, a standard Ca2+ channel blocker, showed selectively higher potency against high K+ compared to CCh-mediated contractions with respective EC50 values of 0.84 mg/mL (0.82–0.96; n = 5) 14.46 mg/mL (12.24–16.38, n = 4). The PDE-inhibitory action of fenchone was further confirmed when its pre-incubation at 3 and 5 mg/mL potentiated and shifted the isoprenaline inhibitory CRCs towards the left, similar to papaverine, whereas the Ca2+ inhibitory-like action of fenchone pretreated tracheal tissues were authenticated by the rightward shift of Ca2+ CRCs with suppression of maximum response, similar to verapamil, a standard Ca2+ channel blocker. Fenchone showed a spasmolytic effect in isolated trachea mediated predominantly by K+ channel activation followed by dual inhibition of PDE and Ca2+ channels. Further in silico molecular docking studies provided the insight for binding of fenchone with Ca2+ channel (−5.3 kcal/mol) and K+ channel (−5.7), which also endorsed the idea of dual inhibition.  相似文献   

20.
《Arabian Journal of Chemistry》2020,13(12):8898-8908
This study reports a facile synthesis of silver nanoparticles (C3-AgNPs) by chemical route, using C3; 2,2′-((1E,1′E)-(propane-1,3-diylbis(azanylylidene))bis(methanylylidene))diphenol (3) and silver nitrate. The formation of nanoparticles was monitored using UV–Vis spectroscopy by the appearance of typical surface plasmon absorption maxima. The synthesized C3-AgNPs were characterized using Fourier-Transform-infrared (FTIR) and atomic force microscopy (AFM) techniques. In addition, the effect of concentration, temperature, time, pH, and stability in salts solution on C3-AgNPs was determined. From AFM, C3-AgNPs were found polydispersed with average size of 29.93 nm. Furthermore, the study reports C3-AgNPs as sensitive protocol for the detection of toxic metal; Hg(II) in tap water. From ten salts tested, C3-AgNPs demonstrated a sensitive and selective spectrophotometric signal and aggregation induced decrease of surface plasmon resonance (SPR) band. The nanosensor probe displayed a sensitive response to Hg(II) in a wide range of concentrations and pH. In addition, the decrease in SPR band of C3-AgNPs due to Hg(II) was not affected by tap water samples. C3-AgNPs also exhibited a redox catalytic potential in dyes degradation. In biological application, C3-AgNPs exhibited significant anticancer and antibacterial potential of 65 to 94% at 24–72 h, and inhibition zone of 7–18 mm, respectively. Hence, the synthesized C3-AgNPs could have promising application in environmental and pharmacological remediation.  相似文献   

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