Antitussive and toxicological evaluation of Vitex negundo

Vitex negundo Linn. (Verbenaceae) is used in traditional medical system for respiratory disorders. This study was carried out to investigate its cough-relieving potential. The antitussive effect of the butanolic extract of V. negundo (Vn) on sulphur dioxide (SO(2))-induced cough was examined in mice. Safety profile of Vn was carried out by observing acute neurotoxicity, median lethal dose (LD(50)) and behavioural signs. Vn dose-dependently (250-1000?mg?kg(-1)) inhibited the cough provoked by SO(2) gas in mice and exhibited maximum protection after 60?min of administration. At 1000?mg?kg(-1), Vn caused maximum cough-suppressive effects i.e. cough inhibition at 60?min was 67.4%, as compared to codeine (10?mg?kg(-1)), dextromethorphan (10?mg?kg(-1)) and saline having cough-inhibitory potential 75.7%, 74.7% and 0%, respectively. LD(50) value of V. negundo was found to be greater than 5000?mg?kg(-1). In toxicity tests, no signs of neural impairment and acute behavioural toxicity were observed at antitussive doses and extract has been well tolerated at higher doses. These results indicate that V. negundo exhibits antitussive effect and it was found devoid of toxicity.     

An efficient synthesis of substituted bis(indolyl)methanes using sodium bromate and sodium hydrogen sulfite in water

Treatment of indole with substituted aldehyde in the presence of equimolar amount of sodium bromate and sodium hydrogen sulfite mixture in water yielded corresponding substituted bis(indolyl)methanes in good yields. This provides a facile and environmentally friendly method towards the synthesis of an important class of organic compounds.     

First report on the kinetics of the uncatalyzed esterification of cellulose under homogeneous reaction conditions: a rationale for the effect of carboxylic acid anhydride chain-length on the degree of biopolymer substitution

The kinetics of the homogeneous acylation of microcrystalline cellulose, MCC, with carboxylic acid anhydrides with different acyl chain-length (Nc; ethanoic to hexanoic) in LiCl/N,N-dimethylacetamide have been studied by conductivity measurements from 65 to 85 °C. We have employed cyclohexylmethanol, CHM, and trans-1,2-cyclohexanediol, CHD, as model compounds for the hydroxyl groups of the anhydroglucose unit of cellulose. The ratios of rate constants of acylation of primary (CHM; Prim-OH) and secondary (CHD; Sec-OH) groups have been employed, after correction, in order to split the overall rate constants of the reaction of MCC into contributions from the discrete OH groups. For the model compounds, we have found that k_(Prim-OH)/k_(Sec-OH) > 1, akin to reactions of cellulose under heterogeneous conditions; this ratio increases as a function of increasing Nc. The overall, and partial rate constants of the acylation of MCC decrease from ethanoic- to butanoic-anhydride and then increase for pentanoic- and hexanoic anhydride, due to subtle changes in- and compensations of the enthalpy and entropy of activation.     

Structure scalars for charged cylindrically symmetric relativistic fluids

We investigate some structure scalars developed through Riemann tensor for self-gravitating cylindrically symmetric charged dissipative anisotropic fluid. We show that these scalars are directly related to the fundamental properties of the fluid. We formulate dynamical-transport equation as well as the mass function by including charge which are then expressed in terms of structure scalars. The effects of electric charge are investigated in the structure and evolution of compact objects. Finally, we show that all possible solutions of the field equations can be written in terms of these scalars.     

Synthesis and Spectroscopy of Novel‐α‐Pyrazolylglycine Derivatives

The synthesis of α‐pyrazolylglycine derivatives(7a‐d) with different substituents, starting from glycine have been pre pared. The spectroscopy of intermediate compounds and the final amino acids have been discussed.     

Brownian motion and thermophoresis effects on unsteady stagnation point flow of Eyring-Powell nanofluid: a Galerkin approach

This article concerns the analysis of an unsteady stagnation point flow of Eyring-Powell nanofluid over a stretching sheet. The influence of thermophoresis and Brownian motion is also considered in transport equations. The nonlinear ODE set is obtained from the governing nonlinear equations via suitable transformations. The numerical experiments are performed using the Galerkin scheme. A tabular form comparison analysis of outcomes attained via the Galerkin approach and numerical scheme (RK-4) is available to show the credibility of the Galerkin method. The numerical exploration is carried out for various governing parameters, namely, Brownian motion, steadiness, thermophoresis, stretching ratio, velocity slip, concentration slip, thermal slip, and fluid parameters, and Hartmann, Prandtl and Schmidt numbers. The velocity of fluid enhances with an increase in fluid and magnetic parameters for the case of opposing, but the behavior is reversed for assisting cases. The Brownian motion and thermophoresis parameters cause an increase in temperature for both cases (assisting and opposing). The Brownian motion parameter provides a drop-in concentration while an increase is noticed for the thermophoresis parameter. All the outcomes and the behavior of emerging parameters are illustrated graphically. The comparison analysis and graphical plots endorse the appropriateness of the Galerkin method. It is concluded that said method could be extended to other problems of a complex nature.     

Solubility of sinapic acid in various (Carbitol + water) systems: computational modeling and solution thermodynamics

Journal of Thermal Analysis and Calorimetry - The solubility and solution thermodynamic properties of a “bioactive nutraceutical” sinapic acid (SA) in different...     

Hydrothermal synthesis of magnetic Fe<Subscript>3</Subscript>O<Subscript>4</Subscript>–nitrogen-doped graphene hybrid composite and its application as photocatalyst in degradation of methyl orange and methylene blue dyes in presence of copper (II) ions

Nanocomposite of Fe₃O₄–nitrogen-doped graphene (Fe₃O₄–NG) was synthesized by single step hydrothermal method. The as-synthesized composite was characterised by various techniques such as powder X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry and thermal analysis (TGA). The catalytic role of synthesized nanocomposite in visible light induced photodegradation of methyl orange (MO; acidic dye) and methylene blue (MB; basic dye) was explored. The role of Cu(II) ions on the photodegradation of the organic dyes was also monitored. Cu(II) ions enhance the photocatalytic activity of nanocomposite by capturing photoelectron, thereby quenching the recombination process of electron–hole pair in photocatalyst.     

Conversion of Waste Tyres into Carbon Black and their Utilization as Adsorbent

Pyrolysis has the potential of transforming used tyres into useful recyclable products. Pyrolytic carbon black is one of the most important products of tyre pyrolysis. Waste tyres were pyrolysed at 450 °C in a batch reactor under atmospheric pressure. The recovered pyrolytic carbon black residues were studied to investigate their characteristics for use as a possible adsorbent. EDX elemental analysis and surface area determinations were used to investigate the distinctive features of pyrolytic carbon black. Due to various inorganic additives of the original tyre that contaminated the carbon black obtained, it was treated with acid for demineralization. The demineralized carbon black was activated at 900 °C in a furnace. It was observed that acid treatment and activation increased the surface areas and decreased the concentration of contaminants. Furthermore, adsorption characteristics of methylene blue on acid‐treated and activated carbon black (prepared via acid treatment) were compared with those of commercial activated carbon in liquid phase adsorption. It was found that adsorption capacity of methylene blue on acid‐treated activated carbon black was greater.     

Synthesis and characterization of biocompatible, thermoresponsive ABC and ABA triblock copolymer gelators

The synthesis of doubly thermoresponsive PPO-PMPC-PNIPAM triblock copolymer gelators by atom transfer radical polymerization using a PPO-based macroinitiator is described. Provided that the PPO block is sufficiently long, dynamic light scattering and differential scanning calorimetry studies confirm the presence of two separate thermal transitions corresponding to micellization and gelation, as expected. However, these ABC-type triblock copolymers proved to be rather inefficient gelators: free-standing gels at 37 degrees C required a triblock copolymer concentration of around 20 wt%. This gelator performance should be compared with copolymer concentrations of 6-7 wt% required for the PNIPAM-PMPC-PNIPAM triblock copolymers reported previously. Clearly, the separation of micellar self-assembly from gel network formation does not lead to enhanced gelator efficiencies, at least for this particular system. Nevertheless, there are some features of interest in the present study. In particular, close inspection of the viscosity vs temperature plot obtained for a PPO43-PMPC160-PNIPAM81 triblock copolymer revealed a local minimum in viscosity. This is consistent with intramicelle collapse of the outer PNIPAM blocks prior to the development of the intermicelle hydrophobic interactions that are a prerequisite for macroscopic gelation.