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51.
The contents of total chlorophyll (T-Chl), carotenoids and phenolics compounds were quantified in the biomasses of Ulva lactuca grown either in normal or artificial sea water under indoor conditions. The antioxidant and antibacterial activities of U. lactuca crude organic extracts ( Ulva- COEs) were determined. Thirty-four compounds in Ulva- COEs were characterised by thin layer chromatography and high-performance liquid chromatography. The major compounds were chlorophyll a (Chl a ) (15.60–30.90%) and b (Chl b ) (12.20–14.89%) , 9-cis β-carotene (13.12–14.47%), α-carotene (11.44–11.47%) and all-trans β-carotene (6.16–29.70%, of total carotenoids).The Ulva- COEs exhibited remarkable antioxidant activity, with an IC50 (concentration which causes a 50% of DPPH radical scavenging activity) values ranged from 16.5 and 18.7 μg mL−1, which could be compared with the synthetic antioxidants: α-tocopherol (14.4 μg mL−1), butylated hydroxyanisol (13.1 μg mL−1) and butylated hydroxyltoluene (13.1 μg mL−1). Also, Ulva- COEs exhibited great potential antibacterial activities against six bacterial strains, with minimal inhibitory concentration values ranged from 0.40 to 0.35 mg mL−1.  相似文献   
52.
Objective: The aim of the present work is to exclusively optimize and model the effect of phospholipid type either egg phosphatidylcholine (EPC) or soybean phosphatidylcholine (SPC), together with other formulation variables, on the development of nano-ethosomal systems for transdermal delivery of a water-soluble antiemetic drug. Tropisetron HCl (TRO) is available as hard gelatin capsules and IV injections. The transdermal delivery of TRO is considered as a novel alternative route supposing to improve BAV as well as patient convenience.

Methods: TRO-loaded ethanolic vesicular systems were prepared by hot technique. The effect of formulation variables were optimized through a response surface methodology using 3?×?22-level full factorial design. The concentrations of both PC (A) and ethanol (B) and PC type (C) were the factors, while entrapment efficiency (Y1), vesicle size (Y2), polydispersity index (Y3), and zeta potential (Y4) were the responses. The drug permeation across rat skin from selected formulae was studied. Particle morphology, drug–excipient interactions, and vesicle stability were also investigated.

Results: The results proved the critical role of all formulation variables on ethosomal characteristics. The suggested models for all responses showed good predictability. Only the concentration of phospholipid, irrespective to PC type, had a significant effect on the transdermal flux (p?Conclusion: The study suggests the applicability of statistical modeling as a promising tool for prediction of ethosomal characteristics. The ethanolic vesicles were considered as novel potential nanocarriers for accentuated transdermal TRO delivery.  相似文献   
53.
Bile salts containing vesicles (bilosomes) represent a portentous vesicular carrier that showed prosperous results in delivering active moieties in the gastrointestinal tract (GIT). In this study, bilosomes were exploited to deliver sulfated polysaccharide–protein complexes of Enteromorpha intestinalis (EHEM) and enhance its activity against hepatocellular carcinoma as well as resist harsh GIT conditions. Bilosomes were prepared using the sodium salt of three different bile acids (cholic, deoxycholic, taurodeoxycholic) and two different nonionic surfactants (Span 40 and 65). The effects of experimental variables were thoroughly studied to obtain an optimum formulation loading EHEM. The selected formulation (EH-Bilo-2) prepared with sodium cholate and Span 65 displayed nano-sized (181.1?±?16.80?nm) spherical vesicles with reasonable entrapment efficiency (71.60?±?0.25%) and controlled release properties; and thus was investigated as anti-hepatocarcinogenic candidate for in vivo studies. Treatment of hepatocellular carcinoma (HCC) bearing rats with EH-Bilo-2 experienced significant decrease in serum α-fetoprotein, endoglin, lipocalin-2, and heat shock protein 70 levels vs. the untreated counterparts. Furthermore, the photomicrographs of their liver tissue sections showed focal area of degenerated pleomorphic hepatocytes with fine fibrosis originating from the portal area. Thus, the optimized bilosomal formulation is a promising delegate for tackling hepatocellular carcinoma owing to its powerful anti-cancer and anti-angiogenic activity.  相似文献   
54.
55.
An environmentally safe, economically, fast, and green synthetic approach was presented in this work for the fabrication of Ag-NP, Co3O4-NP and different weight ratio of Ag/Co3O4-NC. The synthesized samples were characterized by Fourier-transform infrared spectroscopy (FT-IR) and UV–visible spectrophotometry, Transmission Electron Microscopy (TEM), Scanning electron microscopy (SEM) along with X-ray energy dispersive spectroscopy (EDAX), and X-ray diffraction (XRD). The catalytic behaviour of the synthesized samples toward the reduction reaction of 4-nitrophenol in the presence of NaBH4 was studied. It is indicated that the synthesized nanocomposites show a satisfactory catalytic activity. The catalytic reduction of p-NP to p-AP obeys first-order kinetics with rate constant in the following order (Ag-NP> (Ag/Co3O4-NC) ?1:1 > 1:3 > 3:1> Co3O4). This may be attributed to the high dispersion of Ag-NP compared to cobalt oxide nanoparticles. The microbial activity of the samples was analyzed using seven species of pathogenic microorganisms; 1) two species belongs to Gram negative bacteria; Escherichia coli (E.coli), and Salmonella, 2)four species belongs to Gram positive bacteria Marsa, Listeria, Staphylococcus aureus (S. aureus), bacillus subtilis (B.subtilis), and 3) one pathogenic fungal species Candidia. The data show that all samples exhibited an excellent range of inhibition toward all tested pathogenic microorganisms.  相似文献   
56.
Non-small cell lung cancer (NSCLC) is an important sub-type of lung cancer associated with poor diagnosis and therapy. Innovative multi-functional systems are urgently needed to overcome the invasiveness of NSCLC. Carbon quantum dots (CQDs) derived from natural sources have received interest for their potential in medical bio-imaging due to their unique properties, which are characterized by their water solubility, biocompatibility, simple synthesis, and low cytotoxicity. In the current study, ethylene-diamine doped CQDs enhanced their cytotoxicity (98 ± 0.4%, 97 ± 0.38%, 95.8 ± 0.15%, 86 ± 0.15%, 12.5 ± 0.14%) compared to CQDs alone (99 ± 0.2%, 98 ± 1.7%, 96 ± 0.8%, 93 ± 0.38%, 91 ± 1.3%) at serial concentrations (0.1, 1, 10, 100, 1000 μg/mL). In order to increase their location in a specific tumor site, folic acid was used to raise their functional folate recognition. The apoptotic feature of A549 lung cells exposed to N-CQDs and FA-NCQDs was characterized by a light orange-red color under fluorescence microscopy. Additionally, much nuclear fragmentation and condensation were seen. Flow cytometry results showed that the percentage of cells in late apoptosis and necrosis increased significantly in treated cells to (19.7 ± 0.03%), (27.6 ± 0.06%) compared to untreated cells (4.6 ± 0.02%), (3.5 ± 0.02%), respectively. Additionally, cell cycle arrest showed a strong reduction in cell numbers in the S phase (14 ± 0.9%) compared to untreated cells (29 ± 0.5%). Caspase-3 levels were increased significantly in A549 exposed to N-CQDs (2.67 ± 0.2 ng/mL) and FA-NCQDs (3.43 ± 0.05 ng/mL) compared to untreated cells (0.34 ± 0.04 ng/mL). The functionalization of CQDs derived from natural sources has proven their potential application to fight off non-small lung cancer.  相似文献   
57.
The multifunctional air filter, which can provide low resistance to airflow, was prepared from polyacrylonitrile (PAN) nanofibers (NFs) by impregnating zinc oxide (ZnO) nanoparticles (NPs) with photocatalytic activity. Incorporation of ZnO NPs improved the surface roughness and electrostatic charge of electrospun NFs. The PAN/ZnO composite filter with 12 wt%-ZnO showed a filtration efficiency of 98.8% and a pressure drop of 48 Pa for 300 nm aerosol particles, resulting in a quality factor of 0.092 Pa−1. In addition, PAN/ZnO composite exhibited excellent photocatalytic activity in methylene blue (MB) decomposition at 100 and 70.2% efficiencies, respectively, under UV and visible light.  相似文献   
58.
The formation of amyloid-like structures by metabolites is associated with several inborn errors of metabolism (IEMs). These structures display most of the biological, chemical and physical properties of protein amyloids. However, the molecular interactions underlying the assembly remain elusive, and so far, no modulating therapeutic agents are available for clinical use. Chemical chaperones are known to inhibit protein and peptide amyloid formation and stabilize misfolded enzymes. Here, we provide an in-depth characterization of the inhibitory effect of osmolytes and hydrophobic chemical chaperones on metabolite assemblies, thus extending their functional repertoire. We applied a combined in vivo-in vitro-in silico approach and show their ability to inhibit metabolite amyloid-induced toxicity and reduce cellular amyloid content in yeast. We further used various biophysical techniques demonstrating direct inhibition of adenine self-assembly and alteration of fibril morphology by chemical chaperones. Using a scaffold-based approach, we analyzed the physiochemical properties of various dimethyl sulfoxide derivatives and their role in inhibiting metabolite self-assembly. Lastly, we employed whole-atom molecular dynamics simulations to elucidate the role of hydrogen bonds in osmolyte inhibition. Our results imply a dual mode of action of chemical chaperones as IEMs therapeutics, that could be implemented in the rational design of novel lead-like molecules.  相似文献   
59.
Corona treatment of Eosin Y-contaminated water by using a dielectric material that covers the ground electrode to avoid spark discharge (causing erosion), reduce charge leakage, and improve the electric field (as stored electrons and charges) was investigated. Elimination of the organic pollutant by gas-phase discharge above the liquid surface in a point-to-plate configuration with multiple needle electrodes was studied. Eosin Y was chosen as model contaminant because of its toxicity and structure that is hard to degrade. Variables such as solution conductivity, dye concentration, pH, air gap, number of needles, and electrode materials were considered. The degree of removal increases with increasing acidity, decreasing concentration, and increasing number of pins.  相似文献   
60.
The reaction of 5-(1-adamantyl)-4-ethyl or allyl-1,2,4-triazoline-3-thione with formaldehyde solution and various 1-substituted piperazines yielded the corresponding N-Mannich bases. The newly synthesized N-Mannich bases were tested for in vitro inhibitory activities against a panel of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Six compounds showed potent antibacterial activity against one or more of the tested microorganisms, while two compounds exhibited moderate activity against the tested Gram-positive bacteria. None of the newly synthesized compounds were proved to possess marked activity against Candida albicans. The oral hypoglycemic activity of six compounds was determined in streptozotocin (STZ)-induced diabetic rats. Four compounds produced significant strong dose-dependent reduction of serum glucose levels, compared to gliclazide at 10 mg/kg dose level (potency ratio > 75%).  相似文献   
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