Chemometric assessment of thermal oxidation of some edible oils

The effect of microwave heating was studied in six varieties of edible oil. Variations in physicochemical properties were observed and compared with the data obtained by hot plate heating. Fourier-transform infrared spectra of the oils showed substantial variations after both types of heating in the region of hydrogen’s stretching (C–H) vibration, region of double bond’s stretching (C=O), and fingerprint region. The visible spectra of mustard and olive oil showed the reduction in carotenoid, flavonoid, and chlorophyll pigments after heating. The oil samples were discriminated as saturated, monounsaturated, and polyunsaturated fats using chemometric techniques on physical and spectroscopic measurements.     

Inhibitory Effect of Nepeta deflersiana on Climax Bacterial Community Isolated from the Oral Plaque of Patients with Periodontal Disease

Background: The red-complex bacteria are one of the most significant complexes found simultaneously in subgingival plaque next to the periodontal pocket. The current antibacterial treatment is not adequate, and multidrug resistance to it is developing. Henceforth, the antibacterial effect of the ethanolic extract of Nepeta deflersiana was put to test against red-complex bacteria in patients with chronic periodontitis. Methods: Well diffusion and micro broth dilution procedure by Alamar blue were applied to assess the zone of inhibition (ZOI), the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC). Anti-virulence efficacies of the plant extract that comprise of adherence and formation of biofilms were examined by the process of adherence and biofilm production assay. Results: The crude extract of Nepeta deflersiana exhibited significant inhibitory outcome against periodontopathic bacteria with noteworthy MIC (0.78–3.12 mg/mL), inhibitory zone (12–20 mm), as well as MBC (3.12–12.50 mg/mL). The N. deflersiana extract inhibited bacterial adhesion ranging from 41% to 52%, 53% to 66%, and 60% to 79% at the given MIC × 0.5, MIC × 1, and MIC × 2 in succession. Substantial suppression was also developed in the biofilm production of the investigated periodontopathic strains following exposure to numerous concentrations of N. deflersianan extract for a period of 24 and 48 h. Conclusion: These outcomes divulge a new concept that N. deflersiana extract can be utilized to manufacture valuable antibacterial compounds to treat chronic and acute periodontitis. This identifies N. deflersiana as an essential natural source for future drug development.     

Pharmacological Efficacy of Ginseng against Respiratory Tract Infections

Respiratory tract infections are underestimated, as they are mild and generally not incapacitating. In clinical medicine, however, these infections are considered a prevalent problem. By 2030, the third most comprehensive reason for death worldwide will be chronic obstructive pulmonary disease (COPD), according to the World Health Organization. The current arsenal of anti-inflammatory drugs shows little or no benefits against COPD. For thousands of years, herbal drugs have been used to cure numerous illnesses; they exhibit promising results and enhance physical performance. Ginseng is one such herbal medicine, known to alleviate pro-inflammatory chemokines and cytokines (IL-2, IL-4, IFN-γ, TNF-α, IL-5, IL-6, IL-8) formed by macrophages and epithelial cells. Furthermore, the mechanisms of action of ginsenoside are still not fully understood. Various clinical trials of ginseng have exhibited a reduction of repeated colds and the flu. In this review, ginseng’s structural features, the pathogenicity of microbial infections, and the immunomodulatory, antiviral, and anti-bacterial effects of ginseng were discussed. The focus was on the latest animal studies and human clinical trials that corroborate ginseng’s role as a therapy for treating respiratory tract infections. The article concluded with future directions and significant challenges. This review would be a valuable addition to the knowledge base for researchers in understanding the promising role of ginseng in treating respiratory tract infections. Further analysis needs to be re-focused on clinical trials to study ginseng’s efficacy and safety in treating pathogenic infections and in determining ginseng-drug interactions.     

Synchronization in coupled Ikeda delay systems

In this work, we demonstrate the use of a Field Programmable Gate Array (FPGA) as a physical platform for realizing chaotic delay differential equations (DDE). Moreover, using our platform, we also experimentally study the synchronization between two time delayed systems. We illustrate two different experimental approaches – one is hardware co-simulation (using a Digilent Atlys with a Xilinx Spartan-6 FPGA) and the other is analog output (using a Terasic DE2-115 with an Altera Cyclone IV E FPGA).     

Synthesis, structures and phase transitions in the double perovskites Sr2−xCaxCrNbO6

The synthesis and crystal structures of nine members of the rock-salt ordered double perovskites Sr_2−xCa_xCrNbO₆ is presented. The crystal structures of the end members of the series Sr₂CrNbO₆ and Ca₂CrNbO₆ were refined using powder neutron diffraction data and are cubic in and monoclinic in P2₁/n, respectively, in both cases there being considerable anti-site Cr-Nb mixing. Variable temperature and/or composition studies suggest a direct first-order P2₁/n to transition, a suggestion supported by selected area electron diffraction studies.     

Effects of gas pressure on the synthesis and photoluminescence properties of Si nanowires in VHF-PECVD method

Silicon nanowires (SiNWs) were grown on an Au-coated Si(111) substrate at various gas pressures by very high frequency plasma enhanced chemical vapor deposition via the vapor–liquid–solid mechanism. The synthesized SiNWs were characterized by field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, high-resolution transmission electron microscopy, Raman spectroscopy and photoluminescence (PL). The SiNWs were sharp needle-shaped and possessed highly crystalline core and oxide amorphous shell. As the gas pressure increases from 70 mtorr to 85 mtorr, the average diameter of the SiNWs decreases from 250 nm to 70 nm. Furthermore, the density of the nanowires increases with the gas pressure. The PL spectra revealed a peak at about 400 nm and a broadband emission at about 700 nm.     

Novel UV-protective formulations for cotton, PET fabrics and their blend utilizing irradiation technique

A novel coating formulation to impart ultraviolet (UV) protection property to cotton, Polyethylene trephethalate (PET) and cotton/PET fabrics was prepared and gamma rays as an ionizing radiation was utilized for surface curing. Natural occurring aluminum potassium sulfate (Alum) was used individually and in binary coat with Zinc Oxide (ZnO), to induce the UV-blocking properties. It was found that using Alum (0.3 g/ml) caused a prompt increase in ultraviolet protection factor (UPF) over the uncoated fabrics. Moreover, the incorporated ZnO in the binary coat increased the UPF for two to threefold than the stand-alone Alum coating, specially in case of PET coated fabric. Water absorbance and moisture regain of ZnO and Alum/ZnO coated fabrics showed a decrease over the blank samples, due to the usage of oligomer/monomer combination. On contrary, Alum showed a hydrophilic effect with the increase in its content in the formulation. Surface Electron Microscope showed the homogenous coating of fibers. X-ray diffraction (XRD), energy dispersive X-ray (EDX) and water vapor permeability were also tested for coated samples.     

Molecular modeling of the adsorption and initial photocatalytic oxidation step for para-nitrophenol on nano-sized TiO2 surface

In the present work, the non-constrained optimization for three proposed models of PNP molecule onto TiO₂ (100) surface has resulted in three molecular adsorption conformations; a vertical alignment via bridged NO₂, a parallel alignment bridges via NO₂ and OH groups, and a monodentate vertical alignment bridged via OH. The first configuration is the dominant adsorption structure. The adsorption energy for the bridging geometries is found to be much more stable than that of the monodentate conformer. The predicted VDOS spectra indicate that the main interaction between PNP molecule and the surface of TiO₂ takes place through a linkage between the Lewis acid sites, fivefold Ti (V) and fourfold Ti (IV) coordinated titanium surface atoms, and the nitro or phenolic oxygen atoms. Frontier electron theory (FET) and Wheland localization approach (WLA) have been applied for the prediction of the primary ^?OH initiated oxidation intermediates. These approaches highlight similar expectations for the variation in the reactivity of the ring positions, towards the hydroxyl radical attack. By comparison with the available experimental data and other theoretical calculations, it is shown that MSINDO can reproduce literature data with acceptable accuracy.     

Regio‐ and Stereoselective Biomimetic Synthesis of Oligostilbenoid Dimers from Resveratrol Analogues: Influence of the Solvent,Oxidant, and Substitution

Oligostilbenoids are polyphenols that are widely distributed in nature with multifaceted biological activities. To achieve biomimetic synthesis of unnatural derivatives, we subjected three resveratrol analogues to oligomerization by means of one‐electron oxidants. Upon varying the metal oxidant (AgOAc, CuBr₂, FeCl₃ ? 6 H₂O, FeCl₃ ? 6 H₂O/NaI, PbO₂, VOF₃), the solvent (over the whole range of polarities), and the oxygenated substitution pattern of the starting material, stilbenoid oligomers with totally different carbon skeletons were obtained. Here we propose to explain the determinism of the type of skeleton produced with the aid of hard and soft acid/base concepts in conjunction with the solvating properties of the solvents and the preferred alignment by the effect of π stacking.     

An Overview of the Literature on the Synthetic Routes to Azolyloxadiazoles

Published data on the methods of preparation of different azoles linked directly to oxadiazoles are described systematically. This review is divided into classes based on the number of heteroatoms in the azoles connected to oxadiazole ring, and the subtitles are divided according to the type of oxadiazoles isomer.