Rational design of flavonoid based potential inhibitors targeting SARS-CoV 3CL protease for the treatment of COVID-19.

The current outbreak of Coronavirus Disease 2019 (COVID-19) pandemic has reported thousands of deaths worldwide due to the rapid transmission rate and the lack of antiviral drugs and vaccinations. There is an urgent need to develop potential antiviral drug candidates for the prevention of COVID-19 infection. In the present study, a series of potential inhibitors targeting SARS-CoV 3CL protease were rationally designed by incorporating gamma lactam ring, and various fluoro substituted heterocyclic ring systems to the flavonoid scaffold. The prediction of drug-likeness, oral bioavailability, toxicity, synthetic accessibility, and ADMET properties was made by computational means. Quercetin was used as standard. The binding affinity of the ligands towards the 3CL protease target was examined using docking simulations. The designed ligands possess favourable pharmacokinetic and pharmacodynamic properties. Ligand L4, L8, and L14 appeared to be the lead compounds in the series and can be considered for further in-vivo and in-vitro validation.

Ecological effects, remediation, distribution, and sensing techniques of chromium.

Chromium is detected in most ecosystems due to the increased anthropogenic activities in addition to that developed from natural pollution. Chromium contamination in the food chain results due to its persistent and non-degradable nature. The release of chromium in the ecosystem accretes and thereafter impacts different life forms, including humans, aquatic and terrestrial organisms. Leaching of chromium into the ground and surface water triggers several health ailments, such as dermatitis, eczematous skin, allergic reactions, mucous and skin membrane ulcerations, allergic asthmatic reactions, bronchial carcinoma and gastroenteritis. Physiological and biological treatments for the removal of chromium have been discussed in depth in the present communication. Adsorption and biological treatment methods are proven to be alternatives to chemical removal techniques in terms of cost-effectiveness and low sludge formation. Chromium sensing is an alternative approach for regular monitoring of chromium in different water bodies. This review intended to explore different classes of sensors for chromium monitoring. However, the spectrochemical methods are more sensitive in chromium ions sensing than electrochemical methods. Future study should focus on miniaturization for portability and on-site measurements without requiring a large instrument provides a good aspect for future research.

A systematic study of arsenic adsorption and removal from aqueous environments using novel graphene oxide functionalized UiO-66-NDC nanocomposites.

This study investigates the removal of As(V) from aqueous media using water stable UiO-66-NDC/GO prepared via the solvothermal procedure. The synthesized material was analyzed by Raman spectroscopy, UV-visible, X-ray powder diffraction (XRD), Transmission electron microscopy (TEM), Fourier Transform Infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) support its applicability as a super-adsorbent for the adsorption of As(V) ions from aqueous solutions. The effect of various parameters, including initial ion concentration, temperature, adsorbent dose, and pH on the adsorption of As(V) was studied to recognize the optimum adsorption conditions. The qmax obtained for this study using Langmuir isotherms was found at 147.06 mg/g at room temperature. Thermodynamic parameters ΔH°, ΔG°, and ΔS° were also calculated and negative values of ΔG° represent that the As(V) adsorption process occurred exothermically and spontaneously. Meanwhile, theoretical density functional simulation findings are accommodated to support these experimental results. It is observed that the dynamic nature of graphene oxide and the UiO-66 NDC nanocomposite system becomes superior for adsorption studies due to delocalized surface states. UiO-66-NDC/GO also showed high reusability for up four regeneration performances using 0.01 M HCl as a regenerant.

Structure-based drug designing of naphthalene based SARS-CoV PLpro inhibitors for the treatment of COVID-19.

The emergence of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has imposed a greater challenge for the world. Coronavirus has infected over 38.3 million people and caused millions of deaths worldwide. The COVID-19 outbreak has accentuated the need for additional efforts to develop broad-spectrum therapeutics to combat SARS-CoV-2 infection. In the current investigation, an attempt was made to design potential SARS-CoV PLpro inhibitors containing naphthalene and 3,4-dihydro-2H-pyran moieties connected via -NHCO- linker. The ligands obeyed Lipinski's rule and were found to have good drug-likeness and ADMET properties. Docking simulations confirmed strong binding affinity and inhibition potential of the designed ligands against the receptor SARS CoV-2 Papain-like protease (PLpro). LigandL10 incorporating the oxadiazole ring system displayed better binding affinity than the control 5-acetamido-2-methyl-N-[(1R)-1-naphthalen-1-ylethyl]benzamide. Further, the docked complex of LigandL10 was subjected to molecular dynamics (MD) simulation to examine the molecular mechanisms of protein-ligand interactions. The results of the present study are encouraging. Ligand L10 emerged as the most potent ligand in the series and could be considered for further research for the development of potential therapeutics for the treatment of COVID-19.