Optimization of a New Extraction Technique for Analysis of Verbenone and cis-Verbenol in Pine Seeds

Results from a systematic study of the factors affecting extraction of cis-verbenol and verbenone from pine seeds are presented. Five extraction conditions were investigated: extraction solvent, method of extraction, extraction temperature, volume of solvent, and the ratio of the mass of sample to the amount of extraction solvent. The resulting optimized method uses magnetic-stirring-assisted extraction of pine seeds (5 g) with ethyl acetate (75 mL) for 20 min, at room temperature. RSDs were less than 5% for both compounds. GC–FID was used for quantification of cis-verbenol and verbenone in the extracts.     

Equilibrium and kinetic studies for the adsorption of benzene and toluene by graphene nanosheets: a comparison with carbon nanotubes

In this study, graphene nanosheets (GNSs) were adopted as an adsorbent to investigate their characterizations and performance for adsorbing benzene and toluene in aqueous solutions. In order to determine the best fit model for each considered system, nonlinear regressions were used. Experimental data of adsorption were corroborated by the combined Langmuir–Freundlich (Sips) models for the isotherms and pseudo‐first‐order model for the kinetics. As a result, GNSs displayed high affinity to the aromatic hydrocarbons such as benzene and toluene. The high affinity was dominated by π–π interactions to the flat surface and the sieving effect of the powerful groove regions formed by wrinkles on GNS's surfaces. Hydrophobic properties and molecular sizes of benzene and toluene affected the adsorption of GNS. In addition, the favorable adsorption of toluene possibly was due to the increase in the molecular weight, decrease in the solubility, and the increase in the boiling point. A comparative study on the benzene and toluene adsorption revealed that favorable adsorption of GNSs compared with that of carbon nanotubes was consistent with the order of physical properties such as specific surface area and pore's volume. Copyright © 2016 John Wiley & Sons, Ltd.     

Phytochemical and In Silico ADME/Tox Analysis of Eruca sativa Extract with Antioxidant,Antibacterial and Anticancer Potential against Caco-2 and HCT-116 Colorectal Carcinoma Cell Lines

Eruca sativa Mill. (E. sativa) leaves recently grabbed the attention of scientific communities around the world due to its potent bioactivity. Therefore, the present study investigates the metabolite profiling of the ethanolic crude extract of E. sativa leaves using high resolution-liquid chromatography-mass spectrometry (HR-LC/MS), including antibacterial, antioxidant and anticancer potential against human colorectal carcinoma cell lines. In addition, computer-aided analysis was performed for determining the pharmacokinetic properties and toxicity prediction of the identified compounds. Our results show that E. sativa contains several bioactive compounds, such as vitamins, fatty acids, alkaloids, flavonoids, terpenoids and phenols. Furthermore, the antibacterial assay of E. sativa extract showed inhibitory effects of the tested pathogenic bacterial strains. Moreover, the antioxidant activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide (H₂O₂) were found to be IC₅₀ = 66.16 μg/mL and 76.05 μg/mL, respectively. E. sativa also showed promising anticancer activity against both the colorectal cancer cells HCT-116 (IC₅₀ = 64.91 μg/mL) and Caco-2 (IC₅₀ = 83.98 μg/mL) in a dose/time dependent manner. The phytoconstituents identified showed promising pharmacokinetics properties, representing a valuable source for drug or nutraceutical development. These investigations will lead to the further exploration as well as development of E. sativa-based nutraceutical products.     

Heavy-atom kinetic isotope effects,cocatalysts, and the propagation transition state for polymerization of 1-hexene using the rac-(C(2)H(4)(1-indenyl)(2))ZrMe(2) catalyst precursor

Using 13C NMR techniques, the 12C/13C kinetic isotope effects (KIEs) for the polymerization of 1-hexene catalyzed by rac-(C2H4(1-indenyl)2)ZrMe2 in the presence of four different cocatalysts (tris(pentfluorophenyl)borane, tris(pentafluorophenyl)alane, anilinium tetrakis(pentafluorophenyl)borate, and methylalumoxane) have been determined. All cocatalysts yield similar KIEs within experimental uncertainty, with values of 1.009(1) and 1.017(2) at C1 and C2, respectively. Ab initio DFT computational modeling of the polymerization KIE indicates that alkene binding to the catalyst must be reversible, with the majority of the KIE developing in the subsequent migratory insertion reaction.     

Forward quark jets from protons shattering the color glass condensate

We consider the single-inclusive minijet cross section in pA at forward rapidity within the color glass condensate model of high energy collisions. We show that the nucleus appears black to the incident quarks except for very large impact parameters. A markedly flatter p(t) distribution as compared to QCD in the dilute perturbative limit is predicted for transverse momenta about the saturation scale, which could be as large as Q(2)(s) approximately 10 GeV2 for a gold nucleus boosted to rapidity approximately 10 (as at the BNL-RHIC).     

A -normal, not densely normal Tychonoff space

We give an example of a -normal space which is not densely normal.

     

Cytotoxic effect and electrophysiological activity of S-irniine, a synthesised isomer of the natural R-irniine, on human MRC-5 fibroblasts

Numerous original alkaloids are present in tubers of Arisarum vulgare Targ. a species belonging to the Araceae family known in Morocco for its toxicity. Some previous works deal with the activity of these natural compounds as R-irniine. As the enantioselective total synthesis of irniine has been realised, the R- and S-forms were obtained and this last one could be tested. Thus, a study of the cytotoxicity and the electrophysiological activity of S-irniine was carried out on human MRC-5 fibroblasts. A cytotoxic effect of S-irniine at 40 microg/mL was detected on MRC-5 fibroblasts. An electrophysiological study was also carried out on the MRC-5 cells by using the patch-clamp technique and no effect of this compound at this concentration on the outward potassium current of MRC-5 fibroblasts was observed. Thus, this study showed, as it was for R-irniine, that the cytotoxicity of S-irniine was not explained by an effect on the potassium currents.     

Molecular monolayer-mediated control over semiconductor surfaces: evidence for molecular depolarization of silane monolayers on Si/SiO(x)

We show that, for molecules with particularly strong dipoles, their organization into a monomolecular layer can lead to depolarization, something that limits the range over which the substrate's work function can be changed. It appears that, with molecules, depolarization is achieved by changes in orientation and conformation, rather than by charge transfer to the substrate as is common for atomic layers.     

Optimal batch sizing in a multi-stage production system with rework consideration

In a production system, rework process plays an important role in eliminating waste and effectively controlling the cost of manufacturing. Determining the optimal batch size in a system that allows for rework is, therefore, a worthwhile objective to minimize the inventory cost of work-in-processes and the finished goods. In this paper, models for the optimum batch quantity in a multi-stage system with rework process have been developed for two different operational policies. Policy 1 deals with the rework within the same cycle with no shortage and policy 2 deals with the rework done after N cycles, incurring shortages in each cycle. The major components that play a role in minimizing this cost of the system are manufacturing setups, work-in-processes, storage of finished goods, rework processing, waiting-time, and penalty costs to discourage the generation of defectives. The mathematical structure of this rework processing model falls under a nonlinear convex programming problems for which a closed-form solution has been proposed and results are demonstrated through numerical examples, followed by sensitivity analyses of different important parameters. It is concluded that the total cost in policy 2 tends to be smaller than that in policy 1 at lower proportion of defectives if the in-process carrying cost is low. Policy 2 may be preferred when the work-in-process carrying cost is low and the penalty cost is negligible.     

Comparative studies of solid‐state synthesized poly(o‐methoxyaniline) and poly (o‐toluidine)

Poly(o‐methoxyaniline) (POMA) and poly(o‐toluidine) (POT) salts doped with different acids (methanesulphonic acid (MeSA), trifluoroacetic acid (TFA), and hydrochloric acid (HCl)) were synthesized by using solid‐state polymerization method. The polymers were characterized by Fourier transform infrared (FTIR) spectra, ultraviolet–visible (UV–Vis) spectrometry, X‐ray diffraction (XRD), cyclic voltammetry (CV), and conductivity measurements. Transmission electron microscopy (TEM) was done to study the morphologies of POMA and POT salts. The FTIR and UV‐Vis absorption spectra revealed that the reduced phase was predominant in POMA salts, and the pernigraniline phase was predominant in POT salts. It was found that POMA salts displayed higher doping level and conductivity. In contrast, POT salts were lower at doping levels and conductivity. In accordance with these results, the electrochemical activity was also found to be lower in POT salts. The XRD patterns showed that the POMA salts displayed higher crystallinity than POT salts. The results from TEM revealed that the morphologies of POMA salts were different from those of POT salts. Copyright © 2008 John Wiley & Sons, Ltd.