Inhibition of respiratory syncytial virus by Daclatasvir and its derivatives: synthesis of computational derivatives as a new drug development.

The most common cause of respiratory tract illness in newborns and young children is the respiratory syncytial virus (RSV). There is no approved vaccination or specific antiviral medication for RSV infections. Here, an attempt has been made to explore the potential of currently marketed drugs as well as their probable derivatives to improve the possibility of developing stronger medications against RSV. From the 100 synthetic drug compounds library, the best drug molecule was identified through drug-likeness properties, toxicity, molecular docking and molecular dynamics simulations. Molecular Mechanics Generalized Born Surface Area (MM-GBSA) was also a method that was applied in this study. Daclatasvir showed the highest binding energy and appeared as the best drug to inhibit matrix protein and a fusion protein of RSV. Based on Daclatasvir, 40 computational derivatives were made. D28, D34 and D40 showed far better results than the actual drug. Changes in lipophilicity character increase the binding energy of derivatives. Molecular dynamic simulations showed their non-deviated, non-fluctuated and stable complex formation with target proteins. The high number of amino acid contacts throughout the trajectory increases the stability and effectiveness of derivatives. The key to producing a novel medicine to eradicate RSV is provided by derivatives. Daclatasvir will be employed as a potential RSV inhibitor up until that point.Communicated by Ramaswamy H. Sarma.

Threat of respiratory syncytial virus infection knocking the door: a proposed potential drug candidate through molecular dynamics simulations, a future alternative.

The discovery of antiviral approaches to prevent or cure respiratory syncytial virus (RSV) infections is critical, particularly because RSV is one of the most common causes of infant respiratory problems. There is currently no approved vaccination available to treat RSV infections. FDA has approved the drug ribavirin, but it is not sufficient to treat RSV. This work aimed to find and study in silico anti-RSV drugs that target matrix protein and nucleoprotein. In this study, we have identified five drug candidates that had better binding energies than ribavirin. Garenoxacin appeared as top lead compounds between them. AutoDock Vina was used to execute molecular docking of a library of chosen chemicals. The high-score compound was then confirmed using the Maestro 12.3 module's molecular dynamics simulation and the binding energies derived using Prime/Molecular Mechanics Generalized Born Surface Area (Prime/MM-GBSA). Comparative molecular dynamics simulations revealed that garenoxacin has better stability and high residue contacts with high binding affinity than ribavirin. This study showed garenoxacin could prevent RSV infection better than ribavirin. In pursuing a more effective RSV control drug, additional research into these chemicals in vitro and in vivo is essential.

Bimetal (Fe/Zn) doped BiOI photocatalyst: An effective photodegradation of tetracycline and bacteria.

Tetracycline (TC) is one of the most commonly used broad-spectrum antibiotics to treat the bacterial infection. TC antibiotics enter into the environment because of partial metabolism in the humans and animals, thereby increasing the environmental toxicity. Therefore, it is highly needed to treat TC antibiotics from the water system. In this aspect, the present work focus on the synthesis of Fe and Zn (bimetal) incorporated with different concentrations into the bismuth-oxy-iodide (Fe/Zn-BiOI) based photocatalyst materials. The synthesized Fe/Zn-BiOI was tested against photocatalytic degradation of TC antibiotics and bacteria. The band gap value of the synthesized Fe/Zn-BiOI was calculated ~2.19 eV. The incorporation of the Fe and Zn metals within the BiOI aided advantages that increased the reactive sites, oxygen defects, photon adsorption, production of hydroxyl radicals, and decrease the recombination rate, thereby high photo-degradation ability. The maximum degradation of ~83% was observed using Fe/Zn-BiOI-1-1 at 10 mg/L of TC antibiotics concentration. Moreover, ~98% of degradation was observed at pH~10 of the TC antibiotics. The photo-activity against bacteria of the Fe/Zn-BiOI was also determined. The data suggested that the synthesized Fe/Zn-BiOI based photocatalyst materials effectively inhibited the bacterial strains. Therefore, Fe/Zn-BiOI based photocatalyst materials might be promising materials that effectively degrade TC antibiotics as well as bacteria.

Study on Self-Assembled Morphology and Structure Regulation of α-Zein in Ethanol-Water Mixtures.

α-Zein has received widespread attention owing to its unique solubility, amphipathic, and self-assembly properties, which is because of its high proportion of nonpolar amino acids and unique amino acid sequence. The protein self-assembly is a significant and widely observed phenomenon in many scientific areas such as food and biomedicine, among many industries. In this study, we investigated the self-assembly behavior of α-zein and regulated the morphology and structure of the self-assembled α-zein by varying the experimental parameters like pH, ethanol content, induction time, and α-zein concentration during the self-assembly process in ethanol-water mixtures. The nanospheres and nanofibers were observed under different conditions [nanospheres observed under acidic and strongly alkaline (pH > 10.5) conditions or for ethanol content lower than 65% and higher than 75%; nanofibers observed under weakly alkaline (pH 9.5-10.5) conditions or for 65-75% ethanol concentration for induction duration longer than 24 h]. The morphological and structural analyses of the self-assembled α-zein showed that the self-assembly process was accompanied by the transformation of the morphology and conformation of α-zein. The studies on the self-assembly process and mechanism revealed that α-zein first self-assembled into nanospheres, followed by the nanospheres adhering to shape-beaded fibers and finally fibers, accompanied by a structural transformation from the disordered into ordered state. The nanosphere formation is noted to follow the nucleation-based polymerization, and the nanosphere-mediated mechanisms lead to the formation of nanofibers. Moreover, the hydrophobic interactions, hydrogen bonds, and electrostatic interactions are concluded to drive the α-zein self-assembly. The findings from this study are expected to provide a theoretical basis for expanding the commercial applications of α-zein.

Modified melamine-formaldehyde resins improve tensile strength along with antifouling and flame retardancy in impregnation of cellulose paper.

In this study, polyvinyl alcohol (PVA) and benzoguanamine (BG) modified melamine-formaldehyde (MF) resins were used to prepare two high-pressure laminates (HPLs) as well as a pure cellulose paper laminate and core sandwich laminates with the core material of aramid paper (AP) or polypropylene non-woven fabric (PPNF). The tensile strength, flame retardancy and antifouling properties of the modified MF resin laminates were studied and compared with the MF resin laminate. The tensile test results showed that the MF resins modified with BG and PVA improved the tensile strength of the impregnated paper. In comparison with pure kraft cellulose paper laminates, the aramid paper core laminates displayed comparatively higher tensile strength. Antifouling test results indicated that modified MF resin laminates had no obvious change while the MF resin laminate was stained. Thermal stability of the modified resins was investigated by thermogravimetric (TG) analysis and the results showed that the char yield of modified MF resin was higher than that of the unmodified MF resin due to the addition of BG. The modified MF resin laminates exhibited better flame retardancy properties through the analysis of limiting oxygen index (LOI), vertical burning and cone calorimetry (CONE) compared to the MF resin laminate. In addition, the flame retardancy of laminates was further enhanced when prepared with core materials of aramid paper. Scanning electron microscopy analysis of residue char after CONE tests showed that the AP-core laminate formed a dense and stable char layer compared with the loose char layer of the PPNF-core laminate. This study shows a new direction to develop sustainable high-performance flame retardant laminates for commercial decoration application.