Search

In this study, we report one-pot, single step synthesis of silver nanoparticles stabilized by using arbutin. The concentration of reducing agent (NaBH4) used in the preparation was kept at double, and arbutin was used as a stabilizing agent. The confirmation of prepared silver nanoparticles was done by color change and UV-Vis surface plasmon resonance peak at 435 nm in UV-Vis spectrum. Size dispersion of nanoparticles was carried out by Dynamic Light Scattering (DLS) and surface charge on nanoparticles. Stability was analyzed by Zeta potential. A strong negative charge indicated that nanoparticles are well stabilized throughout the solution. Morphology and 3D topographic images were obtained by Atomic Force Microscopy (AFM). The crystalline nature of nanoparticles was elucidated by X-ray diffraction analysis. The size and morphology of solid, well-grinded nanoparticles was proceeded by Scanning Electron Microscopy (SEM). The catalytic activities of nanoparticles were carried out against methylene blue, methyl orange, safranin, and eosin. The results demonstrated that synthesized silver nanoparticles commenced the degradation reaction of dyes mentioned. Prepared silver nanoparticles are found to have adequate catalytic activity, as it can be comprehended in time-dependent UV-Vis spectrums of dyes after treating them with AgNPs.

Polyphosphazenes was synthesized and their self assembly behavior was observed as reported in our previous work [1–5]. A number of experiments were carried out to study the polymerization behavior at various conditions of the polymerization time and temperature. The experimental data were analyzed by graphical and statistical methods and it was found that the polymerization phenomena was controlled by the synthesis time, i.e. Mw = Mo ek s ts, where Mw is molecular weight of the polymer at time ts, M 0(=203.24) is pre-exponential factor in the model and ks is (=10686) is synthesis rate constant for the polymer.

Applications of polyphosphazenes are gaining attention in biomedical industry due to their unique characteristics of being easily degradable. This has been achieved by the replacement of chloro groups with appropriate nucleophiles. In our present study, we have synthesized a degradable polyphosphazene by the replacement of chloro groups with 2-(2-methoxyethoxy) ethanol having controlled molecular weight. Synthesis of poly[bis((methoxyethoxy)ethoxy)phosphazene] (MEEP) is carried out in two steps. First step involves the synthesis of polydichlorophosphazenes (PDCP) from hexachlorocyclo triphosphazene using AlCl3 as catalyst by ring opening polymerization. In the second step, PDCP chlorines are substituted by 2(2-methoxyethoxyethoxy) moiety. The structure of synthesized MEEP is confirmed by phosphorous-31 nuclear magnetic resonance (31P NMR) and hydrogen-1 nuclear magnetic resonance (1H NMR). Molecular weight, molar mass distribution and polydispersity index are determined by Gel Permeation Chromatography (GPC). In vitro, hydrolytic degradation of the MEEP is carried at 37 °C in phosphate-buffered saline (PBS) with neutral, basic and acidic media. Moreover, the experimental data are demonstrated by statistical and graphical methods. The values of the coefficient of determination (R2) were found to be 0.9987, 0.9856 and 0.9359, respectively. The values of the coefficient indicate that the workability of the theoretically fitted models is good. Antibacterial activity of the synthesized polyphosphazene is evaluated against methicillin-resistant Staphylococcus aureus. The potential applications of present study are applicable for biomedical applications such as drug delivery.

In this study, Zn(II) centered complexes with aldimine derivatives were synthesized using green solvent, polyethylene glycol (PEG-400) and amorphous complexes were characterized by FT-IR, multinuclear (1H and 13C NMR), elemental and thermal analysis. Thermogravimetric analysis indicated the extended thermal stability of the synthesized complexes. All the Zn(II) complexes show very significant photoexcitation in the range of 318 – 384 nm and photoemission in the range of 502 – 562 nm. Among all the complexes, Zn(II) complex (3Zn) showed minimum band gap value, 2.35 eV. These amorphous complexes have been reported for their wide applications in biomedical sciences. The synthesized aldimine ligands and Zn(II) complexes were investigated for anti-inflammatory activity and these complexes showed more anti-inflammatory potential than the corresponding aldimine ligands. The solubilization of zinc complexes in sodium dodecyl sulphate was also investigated to reveal the interaction of metal complexes by using UV-Visible spectroscopy and electrical conductivity measurements.

Human glioma is a highly fatal tumor with a significant feature of immune suppression. The functions of PD-L1 refer to co-simulation and immune regulation. To investigate expression and functional activity of PD-L1 in human glioma cell in vivo and in vitro. Expressions of PD-L1mRNA and protein in the human glioma cell line were analyzed with quantitative RT-PCR and flow cytometer; and then expression of PD-L1 in tissue specimens of 10 glioma patients was treated with immunohistochemical analysis; glioma cell and allogeneic CD4+ and CD8+ T cells were co-cultured, and cytokine IFN-γ, IL-2 and IL-10 in cultured supernatant fluid were determined with ELISA; upon blocking the interaction between glioma cell and the immune cell with PD-L1 monoclonal antibody (5H1), surface markers on immune cells were analyzed using flow cytometer. All human glioma cell lines constitutively expressed PD-L1, and IFN-γ induced glioma cell to highly express PD-L1. It was shown through immunohistochemical analysis that glioma specimen expressed PD-L1, while expression of PD-L1 was not observed in normal tissue and normal human brain near the tumor location. The release of IFN-γ and IL-2 was inhibited, while IL-10 was increased slightly. Glioma cell may escape from immune recognition and injury with the help of PD-L1, which is a significant pathogenic mechanism of glioma.

Phytochemical study on Neolamarckia cadamba (Roxb.) Bosser has yielded ten indole alkaloids, neolarmarckine A-E (1–5), cadamine (6), 3β-isodihydrocadambine (7), angustine (8) and naulafine (9) and harmane (10). The structural elucidation of all the compounds were conducted based on the thorough analysis of spectroscopic data and comparison with reported data. The chemotaxonomic significance of all these compounds were summarized. Among all the indole alkaloids, compound 3–5 were new compounds and isolated from Neolamarckia cadamba (Roxb.) Bosser for the first time. Compounds 1 and 2 were only found in Neolamarckia species while compounds 6 and 7 were only isolated from the family of Rubiaceace. Besides, compound 8 has been found in six genera of Rubiaceae and two genera of Apocynaceae while compound 9 was isolated from Neolamarkia species for the first time. Compound 10 can be found in many genera of Rubiaceae and also more than ten families such as Zygophyllaceae, Cyperaceae, Passifloraceae, Bignoniaceae, Sapotaceae, Elaeagnaceae, Leguminosae, Loganiaceae, Apocynaceae, Combretaceae, Chenopodiaceae, Commelinaceae and Polygalaceae.

Linseed oil biodiesel (LSOB) was synthesized from linseed oil by cadmium oxide nanoparticles applying transesterification reaction of oil with methanol. Cadmium oxide nanoparticles were synthesized through the hydrothermal method using cadmium acetate as precursor, sodium hydroxide for precipitation and urea as capping agent. The main analytical tools such as FT-IR, powder XRD and SE microscope were used to characterize newly prepared cadmium oxide nanoparticles. The appearance of new absorption band at 670 cm−1 has been assigned to Cd–O stretching vibration. XRD pattern indicate the purity and gave average particle size of 52 nm by Debye-Scherer formula. SEM images show granular shape of cadmium oxide nanoparticles with average particle size of 43 nm. The formation of linseed oil biodiesel was investigated using FT-IR and proton & carbon-13 NMR. GC-MS analysis of linseed oil biodiesel indicated six types of fatty acid methyl esters ranging from C16–C22 (mixture of both saturated and unsaturated). The fuel properties such as density, viscosity, cloud, pour and flash point were determined and compared with both ASTM standards for biodiesel and diesel.

Synthesis of porous materials is very attractive due to their various applications in era of water purification. The other advantage is due the structural and functionality of stable MOFs-based porous materials. Metal-organic frameworks (MOFs) are spongy like structures that are composed of transition metals coordinately linked or protected via ligands may be responsible for the active centers and large surface area. In this mini review, we have emphasized the development of water stable Zr-MOFs that have been potentially used as emerging adsorbents for cationic and anionic contaminants in water. The main focus of this review is on the detail study of stability as well as the factors affecting the stability of Zr-based MOFs, including the adsorbent capacities, thermodynamics and kinetic studies. Moreover we have discussed the introduction of metal ions to organic linkers having more replaceable atoms that makes them more reliable adsorbents than other conventional adsorbents. Of note the Zr-MOFs exhibit as an emerging platform for the cost effective, eco-friendly approach and interesting adsorbent-adsorbate interactions for water treatment.

Biomonitoring of people exposed to hazardous materials provides opportunities for early identification of several diseases, particularly in those individuals who are constantly exposed to pesticides, such as pesticide operators and workers in pesticide manufacturing industry. However, data on this hot topic are limited in Pakistan. In this study, insecticide toxic effects and biochemical alterations (i.e., damage in DNA and enzyme activity) were studied in blood samples of occupationally exposed individuals from Punjab, Pakistan. Eight out of twenty-seven blood samples (29.6%) of the pesticide operators were found positive in five insecticides, with the maximum concentration found for chlorpyrifos-methyl (0.039 μg/mL). Eleven out of twenty-seven blood samples (40.7%) of the pesticide industry workers were found positive in eight insecticides, with the maximum concentration found for endosulfan (0.051 μg/mL). Comet tail length was 16.88 ± 4.57 μm in pesticide industry workers and 16.33 ± 3.78 μm in pesticide operators, which were significantly higher (P 0.01) than that recorded in the control group (4.84 ± 2.21 μm). Values of serum cholinesterase (SChE) concentration were slightly lower (P 0.05) in exposed individuals, whereas values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) concentration were significantly higher (P 0.01) in exposed individuals compared with control group. Exposure duration and total insecticide concentration in blood samples were positively associated with comet tail length, ALT activity, AST activity, and ALP activity, but negatively with SChE. DNA damage was higher in smokers vs. non-smokers. Also, a positive association was found between comet tail length and number of cigarettes per day. Overall, occupational exposure to insecticides can pose serious health risks to pesticide operators and workers in pesticide manufacturing industry, highlighting the necessity of personal protection in those groups for preventing exposure and resultant health disorders.

Colloidal silver nanoparticles were prepared by rapid green synthesis using different tannin sources as reducing agent viz. chestnut (CN), mangrove (MG) and quebracho (QB). The aqueous silver ions when exposed to CN, MG and QB tannins were reduced which resulted in formation of silver nanoparticles. The resultant silver nanoparticles were characterized using UV-Visible, X-ray diffraction (XRD), scanning electron microscopy (SEM/EDX), and transmission electron microscopy (TEM) techniques. Furthermore, the possible mechanism of nanoparticles synthesis was also derived using FT-IR analysis. Spectroscopy analysis revealed that the synthesized nanoparticles were within 30 to 75 nm in size, while XRD results showed that nanoparticles formed were crystalline with face centered cubic geometry.

The study of biofilms has skyrocketed in recent years due to increased awareness of the pervasiveness and impact of biofilms. It costs the USA literally billions of dollars every year in energy losses, equipment damage, product contamination and medical infections. But biofilms also offer huge potential for cleaning up hazardous waste sites, filtering municipal and industrial water and wastewater, and forming biobarriers to protect soil and groundwater from contamination. The complexity of biofilm activity and behavior requires research contributions from many disciplines such as biochemistry, engineering, mathematics and microbiology. The aim of this review is to provide a comprehensive analysis of emerging novel antimicrobial techniques, including those using myriad organic and inorganic products as well as genetic engineering techniques, the use of coordination complex molecules, composite materials and antimicrobial peptides and the use of lasers as such or their modified use in combination treatments. This review also addresses advanced and recent modifications, including methodological changes, and biocide efficacy enhancing strategies. This review will provide future planners of biofilm control technologies with a broad understanding and perspective on the use of biocides in the field of green developments for a sustainable future.

Alkaloid extracts of leaves (OOL) and bark (OOB) of Ochrosia oppositifolia, as well as isoreserpiline (ISR), the major alkaloid isolated from OOL and OOB, were investigated as potential corrosion inhibitors for mild steel (MS) in 1 M HCl medium. The inhibition properties of these phytoconstituents were studied using electrochemical techniques (potentiodynamic polarization measurements and electrochemical impedance spectroscopy, EIS) and scanning electron microscopy (SEM). The results indicated that these green inhibitors effectively reduced the corrosion rate. Polarization studies showed that these inhibitors decreased the corrosion current densities by a mixed-mode mechanism. The EIS data were analyzed by an equivalent circuit model for the electrode/electrolyte interface. SEM observations confirmed the existence of an adsorbed protective film of green inhibitors, and the adsorption was found to follow the Langmuir adsorption isotherm. FTIR and molecular modeling studies were also employed and revealed t...

The efficacy of the biosorbent coconut hust (Cocos nucifera) was tested for the removal of lead, copper, zinc, and nickel metal ions using batch experiments in multimetal solution system under controlled experimental conditions. It is found that metal sorption increases when the equilibrium metal concentration rises. At highest experimental solution concentration (150mg/L), the removal of metal ions was 92.52% for lead, 79.55% for copper, 63.23% for zinc, and 68.10% for nickel, while at lowest experimental solution concentration (25mg/L), the removal of metal ions was 94.80% for lead, 86.81% for copper, 84.63% for zinc, and 82.36% for nickel. Biosorption equilibrium isotherms were plotted for metal uptake capacity (q) against residual metal concentrations (Cf) in solution. The q vs. Cf sorption isotherm relationship was mathematically expressed by Langmuir and Freundlich models. The values of separation factor were between zero and one indicating favorable sorption for four tested metals on the biosorbent. The surface coverage values were approaching unity with increasing solution concentration, indicating effectiveness of the biosorbent.

Development of desalination technologies has been identified as vital to fulfilling future water demand. In this research, composite membrane with polyvinyl alcohol (PVA) as separating layer material while cellulose acetate (CA) and polyethylene glycol (PEG) as supporting layer material were used. In the present research work, the synthesis and characterization of a multilayer PVA/CA/PEG membrane was attempted where membrane performance and applicability were investigated for reverse osmosis desalination of different feed concentrations of groundwater, brackish, highly saline, and also extremely saline water (seawater). Values of both salt rejection and water flux were assessed as a measure of membrane efficiency. In addition to suitable application of the prepared synthetic membranes, the antimicrobial sustainability was also evaluated where prospective function against gram-positive and gram-negative bacteria was depicted. It can be concluded by this work that multilayer PVA/CA/PEG membrane per...

The inhibition effect of Neolamarckia cadamba crude extract (bark, leaves) and pure alkaloid (3β-isodihydrocadambine) were investigated for mild steel corrosion in 1 M HCl medium. Potentiodynamic polarization, electrochemical impedance, scanning electron microscopy, FTIR spectroscopy and molecular modelling were employed for this study. Results showed that crude extracts and 3β-isodihydrocadambine reduced the corrosion rate significantly at all concentrations. Polarization measurements indicated that these green inhibitors acted through mixed type inhibition. SEM studies evidenced the formation of a protective film over metal surface while FTIR, supported by molecular modelling proved that this shielding effect was caused by alkaloids, particularly 3β-isodihydrocadambine.

The Cholistan Desert is an extension of the Great Indian Desert, covering an area of 26,330 km2. The desert can be divided into two main geomorphic regions: the northern region, known as Lesser Cholistan, constituting the desert margin and consisting of a series of saline alluvial flats alternating with low sand ridges/dunes; and the southern region, known as Greater Cholistan, a wind-resorted sandy desert comprised of a number of old Hakra River terraces with various forms of sand ridges and inter-ridge valleys. Cholistan Desert presents a complex pattern of alluvial and aeolian depositions. In the present study we evaluated the nutritive value of different accessions of the perennial range grass Cenchrus ciliaris collected from the Cholistan Desert, Pakistan. Standard method, Benedict’s quantitative reagent for carbohydrates, crude protein and nitrogen by the Kjeldahl method, mineral analysis by flame photometer and estimation of crude fiber by using acid base treatment, were utilized. The results suggest that Cenchrus ciliaris has medicinal and nutritional importance, and that it could be a good source of important nutrients for humans, helping to alleviate poverty in poor local communities.

The inhibition effect of mild steel (MS) corrosion in 1 M HCl was studied by the addition of indole alkaloids (crude) isolated from Alstonia angustifolia var. latifolia (A. latifolia) leaves at 303 K. Potentiodynamic polarization, impedance spectroscopy, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) analyses were used for this study. Results show that the isolated alkaloid extract of A. latifolia is a good inhibitor and exhibited maximum inhibition efficiency (above 80%) at concentrations between 3 and 5 mg/L. Polarization measurements indicated that the inhibitor does not alter the mechanism of either anodic or cathodic reactions and acted as mixed-type inhibitor. The inhibition efficiencies of both electrochemical techniques are found to be in good agreement and adsorption of inhibitor follows Langmuir isotherm. Adsorption of inhibitor over metal surface was well supported by the SEM studies, while FTIR studies evidenced the presence of indole alkaloids as green inhibitor that reduces the rate of corrosion.

Two new indole alkaloids, neolamarckines A and B (1, 2) were isolated from the leaves of Neolamarckia cadamba (Rubiaceae). Structural elucidation of 1 and 2 was performed by combination of 2D-NMR and circular dichroism (CD) spectra, and chemical correlations. Neolamarckine A (1) showed inhibition of inducible nitric oxide synthase (iNOS) dose dependently.

The study of biofilms has skyrocketed in recent years due to increased awareness of the pervasiveness and impact of biofilms. It costs the USA literally billions of dollars every year in energy losses, equipment damage, product contamination and medical infections. But biofilms also offer huge potential for cleaning up hazardous waste sites, filtering municipal and industrial water and wastewater, and forming biobarriers to protect soil and groundwater from contamination. The complexity of biofilm activity and behavior requires research contributions from many disciplines such as biochemistry, engineering, mathematics and microbiology. The aim of this review is to provide a comprehensive analysis of emerging novel antimicrobial techniques, including those using myriad organic and inorganic products as well as genetic engineering techniques, the use of coordination complex molecules, composite materials and antimicrobial peptides and the use of lasers as such or their modified use in combination treatments. This review also addresses advanced and recent modifications, including methodological changes, and biocide efficacy enhancing strategies. This review will provide future planners of biofilm control technologies with a broad understanding and perspective on the use of biocides in the field of green developments for a sustainable future.

International audience; A new indole alkaloid; neonaucline (1), along with six known compounds-Cadamine (2), naucledine (3), harmane, benzamide, cinnamide and blumenol A-were isolated from the leaves of Ochreinauclea maingayii (Rubiaceae). In addition to that of compound 1, (13)C-NMR data of cadamine (2) and naucledine (3) were also reported. Structural elucidations of these alkaloids were performed using spectroscopic methods especially 1D- and 2D-NMR, IR, UV and LCMS-IT-TOF. The excellent vasorelaxant activity on isolated rat aorta was observed for the alkaloids 1-3 after injection of each sample at 1 × 10(-5) M.