Advanced Journal of Chemistry, Section A
Volume:5 Issue: 3, Summer 2022

Waste tires left in the environment are now becoming a global problem. On the other hand, the use of minerals consumed in the construction industry, in addition to being expensive, may reduce the natural mineral reserves around us. Using waste tire powder to make Autoclaved Aerated Concrete (AAC) is cost-effective. The presence of rubber powder inside the AAC leads to the toughness of the concrete and increases the elongation at break, and gives the plastic behavior to the concrete. In this study, rubber powder of different sizes was used as a filler inside the autoclaved concrete. The presence of elastic rubber particles enhances the sound absorption of AAC. The results revealed that by changing the amount of aluminum added to the concrete mixture, the impact of rubber addition on the density of AAC could be controlled. Reducing the particle size of tire powder also increases the sound absorption of AAC.

Hepatitis C virus (HCV) infection promotes death rates worldwide. As a result, there is a constant need to improve current HCV therapy and produce new drugs. The NS3/A4 enzyme plays a critical role in the HCV entire lifespan and proliferation. Consequently, inhibitors of the HCV NS3/A4 enzyme are a great spot to start exploring new drug candidates. In this study, the high throughput in silico screening of the Pubchem database was used to analyze a set of ketoamides as HCV NS3/A4 enzyme inhibitors to find a novel potential drug as a lead candidate. To Voxilaprevir as a reference medicine, our findings revealed that three HCV NS3/A4 protease inhibitors (Pubchem CID: 44158040, 44158107, and 11479303) were identified as the best drugs for blocking hepatitis C virus NS3/A4 protease. The QSAR was performed to study the relationships between the structural features of the targets and their binding affinity by developing statistical models. The reported compounds had a higher binding affinity for the target receptor than Voxilaprevir, the reference drug. This study could be important in understanding the physicochemical and binding affinity of HCV NS3/A4 inhibitors in order to find new and improved HCV antiviral drugs.

A ternary nanocomposite containing natural rubber, butadiene rubber, and styrene-butadiene rubber (NR/BR/SBR blend) was prepared in 25/25/50 (phr), on which the effect of adding carbon black, nano clay )C15A), and nano-silica was examined. Rheometric, tensile, and hardness measurement tests were performed on the prepared samples. The nano silica-containing sample showed an inhibitory effect in curing, while the modified nano clay-containing sample showed an accelerating effect on the curing process. The results revealed that the presence of nano-silica caused higher elongation at break. TEM analysis was performed from cross-linked samples to ensure the exfoliation of nano additives in the matrix. The results confirmed the suitable distribution and dispersion of the nanoparticles in the composite samples.

In this study, aqueous extracts of the leaf and root of Olax subscorpioidea were used as solvent, reducing and stabilizing agents in synthesizing silver nanoparticles (AgNPs). The change in color from colorless to dark brown indicated the AgNPs formation. The UV-Vis spectra showed active absorption at 460 nm for the root extract mediated AgNPs attributed to the surface plasmon resonance of the AgNPs. This absorbance is quite intense compared to that of the leaf, which is slightly shifted to a higher wavelength of 465 nm. The FTIR spectra showed absorption bands attributed to O-H and N-H stretching vibrations of the phenolic/amide groups. In addition, the bands due to symmetric stretching vibrations of C-H and carbonyl (C=O) groups are also observed. The bioactive molecules present in the plant extracts do stabilized not only the metal nanoparticles but also play the role of modifying the surface of the particles owing to their different functionalities. The textural properties studied using Brunauer-Emmett-Teller (BET) method gave a specific surface area of 22.84 and 39.8 m2/g, respectively for root and leaf mediated AgNPs. Scanning electron microscopy (SEM) revealed monodisperse microspheres AgNPs, while the transmission electron microscopy (TEM) showed particles in the nanosize regime. The results of the antimicrobial activities showed the Olax subscorpioidea mediated-AgNPs to be effective in inhibiting the growth of bacterial strains more than the antibiotic drugs under investigation.

Obesity, a lipid metabolic disorder characterized by excess fat deposition in the adipose tissue, is among the leading top global health challenges. The only Food and Drug Agency (FDA) approved drug (Orlistat®) for its treatment has shown some adverse effects. To find new compounds that may be more effective or with less adverse effects compared to Orlistat®. Catechin and chlorogenic acid were computationally studied using molecular docking and validated with molecular dynamics simulation techniques. The ADMET and drug-likeliness evaluation of the two compounds was carried out in silico. The binding affinities, structural stability, and flexibility vis-a-vis root-mean-square deviation (RMSD) and root-mean-square fluctuations (RMSF) plots, hydrogen bonding, and surface area analysis of the two compounds were compared to the Orlistat®. It was found that the selected two compounds passed Lipinski’s rule of 5 and other parameters expected of a drug. In addition, both catechin and chlorogenic acid exhibited good docking scores, better fit and molecular interactions, good structural stability, and flexibility compared to Orlistat®.

Terpenoids are definite secondary metabolites with active therapeutic components that contribute to plants’ medicinal potential. Strychnos innocua is a Loganiaceae family medicinal plant found in various African countries. This study reports the isolation, characterization, and molecular docking analyses of Linalool (1) and Nerolidol (2) from ethyl acetate root bark extract of S. innocua. Their structures were validated using mass spectrometry, nuclear magnetic resonance (1D and 2D NMR), and compared with literature data. This is a novel report of terpenoids isolated from S. innocua root bark. An in silico docking examination revealed the binding energies of Linalool with the binding sites of Staphylococcus aureus pyruvate carboxylase (PDB: 3HO8) and Pseudomonas aeruginosa virulence factor regulator (PDB: 2OZ6) were -4.7 and –5.6 kcal/mol, respectively. Furthermore, the binding energies of Nerolidol with the binding sites of S. aureus and P. aeruginosa were -5.8 and -6.9 kcal/mol, respectively. Compared to ciprofloxacin (standard drug), which showed binding energies of -6.6 and -8.7 kcal/mol, respectively. This study concluded that Linalool and Nerolidol are abundant in the root bark of S. innocua. At the same time, docking results revealed that the compounds had moderate interactions with S. aureus and P. aeruginosa, exhibiting antibacterial effects.

The SPR of AuNPs as a new analytical method is used to detect drugs and species through the aggregation of Au-nanoparticles. In this study, we reduced gold ion using citrate and then the surface of nano particles was modified by L-cysteine. The multivariable calibration method of SPR provide a highly precise, somehow can make an error less than 6%. As compared a highly selective and sensitive ternary determination of Amphetamine (AMP), Methamphetamine (M-AMP) and Morphine (MOR) based on the proposed method is not needed to a higher amounts of the reagents. As rose the concentration of the addictive, the color of AuNPs altered from a wine red to blue which was easily noticeable by naked eyes. A multivariable calibration model along with three dimensional methods like PARAFAC, within the analysis of SPR adsorption could provide a high functionality as they fitted the experimental data as well. A chemical based kite and chemo metrics provide an excellent kite, which in turn is unique as experimentally confirmed. PARAFAC is a multi-way method rooted in psychometrics. Notably, chemometrics and the related areas due to various reasons such as high computational power, consciousness of the method and its potentials, the improved complication of data, have received much more considerations.