Synthesis of Silver Nanoparticles from Extracts of Wild Ginger (Zingiber zerumbet) with Antibacterial Activity against Selective Multidrug Resistant Oral Bacteria

Antibiotic resistance rate is rising worldwide. Silver nanoparticles (AgNPs) are potent for fighting antimicrobial resistance (AMR), independently or synergistically. The purpose of this study was to prepare AgNPs using wild ginger extracts and to evaluate the antibacterial efficacy of these AgNPs against multidrug-resistant (MDR) Staphylococcus aureus, Streptococcus mutans, and Enterococcus faecalis. AgNPs were synthesized using wild ginger extracts at room temperature through different parameters for optimization, i.e., pH and variable molar concentration. Synthesis of AgNPs was confirmed by UV/visible spectroscopy and further characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy analysis (EDXA), and Fourier-transform infrared spectroscopy (FTIR). Disc and agar well diffusion techniques were utilized to determine the in vitro antibacterial activity of plant extracts and AgNPs. The surface plasmon resonance peaks in absorption spectra for silver suspension showed the absorption maxima in the range of 400–420 nm. Functional biomolecules such as N–H, C–H, O–H, C–O, and C–O–C were present in Zingiber zerumbet (Z. zerumbet) (aqueous and organic extracts) responsible for the AgNP formation characterized by FTIR. The crystalline structure of ZZAE-AgCl-NPs and ZZEE-AgCl-NPs was displayed in the XRD analysis. SEM analysis revealed the surface morphology. The EDXA analysis also confirmed the element of silver. It was revealed that AgNPs were seemingly spherical in morphology. The biosynthesized AgNPs exhibited complete antibacterial activity against the tested MDR bacterial strains. This study indicates that AgNPs of wild ginger extracts exhibit potent antibacterial activity against MDR bacterial strains.     

First-principles study of vibrational properties of TiSiO4 clusters

First-principles calculations were performed to investigate the vibrational properties of monomers and dimers of titania, silica, and titania-silica hybrid clusters. Density functional theory-based formulism was employed to optimize the geometry at the B3LYP level and calculate the infrared and Raman spectra of the clusters by using the GGA-PBE exchange-correlation functional. It was found that the vibrational spectra of Ti₂O₄, Si₂O₄, and TiSiO₄ hybrid clusters provide fingerprint information about structures and structural transitions during the formation of cluster structures. In the case of Si₂O₄ the mode at 410 cm⁻¹ exhibited the largest vibration of Si atoms, whereas in the case of Ti₂O₄ the mode at 442 cm⁻¹ exhibited the largest vibration of Ti atoms. The hybrid cluster TiSiO₄ was structured using two different methods to explore the effects of starting geometry on the structures and vibrational modes of the clusters. The structural properties of the clusters remained unchanged but vibrational modes were found to be different. It is found that Si shows notable vibrations, but the metal atom Ti merely shows any vibration in the case of TiSiO₄ hybrid clusters. The low and intermediate frequency modes were stiffened, whereas the three highest frequency modes were softened when the starting geometry of the hybrid clusters was changed from Si₂O₄ to Ti₂O₄.     

Voltammetry and Spectroscopy Study of In Vitro Interaction of Fenitrothion with DNA

The interaction of Fenitrothion with DNA has been studied using the voltammetric and spectroscopic methods. An irreversible reduction was concluded from the CV data of Fenitrothion. The values of (αn)_f=1.91 and (αn)_b=2.06 were measured and the reduction process of Fenitrothion was performed with 4 electrons. By using non‐linear regression analysis of CV data, the binding constant, binding site size, and diffusion coefficient for free Fenitrothion (D_f) and DNA‐Fenitrothion (D_b) were calculated as: 1.03×10⁴, 1.204, 5.2×10^?4 and 1.72×10^?5, respectively. Also the voltammetric, spectroscopic, thermodynamic and activation energy of DNA‐Fenitrothion complex revealed that the mode of interaction might be partial‐intercalative and complex formation is entropy favored.     

Synthesis and characterization of new soluble and thermally stable poly(ester-imide)s derived from N-[3,5-bis(N-trimellitoyl)phenyl]phthalimide and various bisphenols

A new dicarboxylic acid chloride (2) bearing three preformed imide rings was synthesized by treating N-(3,5-diaminophenyl)phthalimide with trimellitic anhydride followed by refluxing with thionyl chloride. A novel family of aromatic poly(ester-imide)s with inherent viscosities of 0.27-0.35 dl g⁻¹ were prepared from 2 with various bisphenols such as resorcinol (3a), hydroquinone (3b), 2,2′-dihydroxybiphenyl (3c), 4,4′-dihydroxybiphenyl (3d), bisphenol-A (3e), 2,2′-dimethyl-4,4′-dihydroxybiphenyl (3f), 1,5-dihydroxynaphthalene (3g), 2,7-dihydroxynaphthalene (3h), and 2,2′-dihydroxy-1,1′-binaphthyl (3i) by high-temperature solution polycondensation in nitrobenzene using pyridine as hydrogen chloride quencher. All of the resulted polymers were fully characterized by FT-IR and NMR spectroscopy and elemental analyses. The poly(ester-imide)s exhibited excellent solubility in some polar organic solvents. From differential scanning calorimetry, the polymers showed glass-transition temperatures between 259 and 353 °C. Thermal behaviors of the obtained polymers were characterized by thermogravimetric analysis and the 10% weight loss temperatures of the poly(ester-imide)s were found to be in the range between 451 and 482 °C in nitrogen. Furthermore, crystallinity of the polymers was estimated by means of wide-angle X-ray diffraction.     

Geological and radiological studies of the Mount Arafat, Mekkah, Saudi Arabia

Mount Arafat is a sacred place for Muslims. It has been classified as a granodiorite rock which mainly consists of feldspar and quartz, muscovite, etc. During the Hajj and Umra, Muslims visit this holly place and stay there for some time. In order to study the geology and thermal history as well as to assess the radiological hazards due to the presence of primordial radionuclides, systematic studies using petrographic, fission track dating and γ-spectrometric (HPGe) techniques were carried out. Our study yielded fission track age of 9.13 ± 1.05 Ma of the Mount Arafat granodiorite. Rifting, magmatism, volcanism and sea floor spreading that resulted in the formation of Red Sea seems may have altered the original age of the Arafat granodiorite under study to 9.13 ± 1.05 Ma. Measured radioactivity concentrations due to ²²⁶Ra, ²³²Th and ⁴⁰K were found to be 10.75 ± 3.92, 29.21 ± 4.34 and 664.49 ± 7.45 Bq kg^?1, respectively. From the measured radioactivity, gamma index (Iγ) and radium equivalent (Ra_eq) were calculated as 0.402 and 103.23 Bq kg^?1 whereas outdoor external dose (D_out) and annual effective dose (E_out) were estimated to be 40.30 nGyh^?1 and 0.045 mSvy^?1 respectively. All the above mentioned values are well below the recommended limits. The Mount Arafat thus does not pose any radiological health hazard to the general public.     

Nanofibrous Scaffolds with Biomimetic Composition for Skin Regeneration

Applied Biochemistry and Biotechnology - Treatments of skin injuries caused by trauma and diseases are among the most considerable medical problems. The use of scaffolds that can cover the wound...     

Sulfonated nanohydroxyapatite functionalized with 2-aminoethyl dihydrogen phosphate (HAP@AEPH2-SO3H) as a reusable solid acid for direct esterification of carboxylic acids with alcohols

Research on Chemical Intermediates - Sulfonated nanohydroxyapatite functionalized with 2-aminoethyl dihydrogen phosphate (HAP@AEPH2-SO3H) efficiently catalyzed direct esterification of carboxylic...     

Sulfonated Honeycomb Coral (HC-SO<Subscript>3</Subscript>H): a new,green and highly efficient heterogeneous catalyst for the rapid one-pot pseudo-five component synthesis of 4,4′-(aryl methylene) bis(3-methyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-5-ol)s

Sulfonated Honeycomb Coral (HC-SO₃H), has been synthesized from the reaction of Honeycomb Coral with chlorosulfonic acid as sulfonating agent. The as-synthesized catalyst was characterized via XRF, FT-IR, TGA, SEM–EDS, XRD, BET and pH analysis. The superior catalytic activity of HC-SO₃H was investigated for the synthesis of 4,4′-(aryl methylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives through the one-pot pseudo-five component reactions. The main advantages of this protocol include simple procedure, excellent yields and short reaction times besides the non-toxicity, high stability and reusability of the catalyst.     

Representation of real Riesz maps on a strong <Emphasis Type="Italic">f</Emphasis>-ring by prime elements of a frame

In classical topology, it is proved that for a topological space X, every bounded Riesz map \(\varphi :C (X) \rightarrow {\mathbb {R}}\) is of the from \({\hat{x}}\) for a point \(x\in X\). In this paper, our main purpose is to prove a version of this result by lattice-valued maps. A ring representation of the from \(A\rightarrow {\mathbb {R}}\) is constructed. This representation is denoted by \(\widetilde{p_c}\) that is an onto f-ring homomorphism for every \(p\in \Sigma L\), where its index c, denotes a cozero lattice-valued map. Also, it is shown that for every Riesz map \(\phi :A\rightarrow {\mathbb {R}} \) and \(c\in F(A, L)\) with specific properties, there exists \(p\in \Sigma L\) such that \(\phi =\phi (1)\widetilde{p_c}\).     

Carrier-mediated hollow fiber liquid-phase microextraction for preconcentration followed by spectrophotometric determination of amoxicillin

Preconcentration followed by ultraviolet spectrophotometric determination of amoxicillin (Amox) in pharmaceuticals and water samples by using a three-phase hollow fiber microextraction technique based on carrier-mediated transport has been presented. Amox was extracted from an aqueous solution (source phase) at pH 9.0 into 1-octanol containing 5% (w/v) Aliquat-336 impregnated in the pores of a hollow fiber. It was then back-extracted into NaCl solution (pH = 4.0) which was already positioned as the receiving phase inside the lumen of the hollow fiber. The extraction took place due to the concentration gradient of the counterion between the source and the receiving phases. Under the optimized conditions, an enrichment factor of 240 and a limit of detection of 0.2 μmol L⁻¹ were obtained. The calibration curve was linear (R² = 0.9967) in the concentration range of 0.5–10.0 µmol L⁻¹ Amox. The interday relative standard deviation (n = 9) and the intraday relative standard deviation (n = 3) for 1.0 × 10⁻⁶ mol L⁻¹ Amox solution were 7.3 and 6.4%, respectively.