ABSTRACT
COVID-19 is caused by SARS-CoV-2 which has structural and non-structural proteins (NSP) essential for infection and viral replication. There is a possible binding of SARS-CoV-2 to the beta-1 chain of hemoglobin in red blood cells and thus, decreasing the oxygen transport capacity. Since hydroxychloroquine (HCQ) can accumulate in red cells, there is a chance of interaction of this drug with the virus. To analyze possible interactions between SARS-CoV-2 NSP and hemoglobin with the HCQ using molecular docking and implications for the infected host. This research consisted of a study using bioinformatics tools. The files of the protein structures and HCQ were prepared using the AutoDock Tools software. These files were used to perform molecular docking simulations by AutoDock Vina. The binding affinity report of the generated conformers was analyzed using PyMol software, as well as the chemical bonds formed. The results showed that HCQ is capable of interacting with both SARS-CoV-2 NSP and human hemoglobin. The HCQ/NSP3 conformer, HCQ/NSP5, HCQ/NSP7-NSP8-NSP12, HCQ/NSP9, HCQ/NSP10-NSP16 showed binding affinity. In addition, the interaction between HCQ and hemoglobin resulted in polar bonds. Interaction between SARS-CoV-2 NSP and HCQ indicates that this drug possibly acts by preventing the continuity of infection.Copyright © 2023 Tehran University of Medical Sciences.
ABSTRACT
Context: COVID-19 was caused by the spread and transmission of SARS-CoV-2 at the end of 2019 until now. The problem comes when antiviral drugs have not yet been found and patients infected with SARS-CoV-2 can trigger a cytokine storm condition due to the effects of viral replication. Indonesia has various kinds of medicinal plants, such as Sonchus arvensis L., which are used as medicinal plants. Aim(s): To analyze the activity of the inhibitor as SARS-CoV-2 antiviral agents from n-hexane fractions of S. arvensis leaves. Method(s): The sample was collected from GC-MS analysis, PubChem, and Protein Databank database, then drug-likeness identification using Lipinski Rule of Five server and bioactive prediction of bioactive compounds as inhibitor activity was conducted by Molinspiration server. Furthermore, the docking simulation was performed using PyRx 0.9.9 software to determine the binding activity, molecular interaction by Discovery Studio software to identify position and interaction type, 3D molecular visualization by PyMol 2.5. software, and dynamic by CABS-flex 2.0 server to predict interaction stability. Result(s): alpha-Amyrin and beta-amyrin from n-hexane fractions of S. arvensis leaves had activity as SARS-CoV-2 inhibitors through interactions on helicase, RdRp, Mpro, and RBD-Spike, both compounds had more negative binding affinity than control drug and can produce stable chemical bond interactions in the ligand-protein complexes. However, the results were merely computational, so they must be validated through an in vivo and in vitro research approach. Conclusion(s): Sonchus arvensis L. leaves were predicted to have SARS-CoV-2 antiviral through inhibitor activity by alpha-amyrin and beta-amyrin. Copyright © 2022 Journal of Pharmacy & Pharmacognosy Research.
ABSTRACT
The contagious coronavirus disease-2019 pandemic has led to an increasing number of disposable face masks (DFMs) abandoned in the environment, when they are exposed to the air condition, the broken of chemical bond induced aging is inevitably occurred which meantime would cause a drastic decrease of the mechanical flexibility. However, the understanding of between chemical bond change related to aging and its micromechanical loss is limited due to the lack of refined techniques. Herein, the atomic force microscopy (AFM) technique was firstly used to observe the aging process induced by methine of the polypropylene-based DFMs. By comparing the micromechanical properties loss, the influences of humidity and light density on the DFM aging were systematically studied in the early 72 h, and it revealed that the increasing scissions number of the easiest attacked methine (Ct-H) can gradually decrease the micromechanical properties of the polypropylene (PP)-based DFM. Furthermore, the results are also validated by the in- situ FTIR and XPS analysis. This work discloses that an aging process can be initially estimated with the micromechanical changes observed by AFM, which offers fundamental data to manage this important emerging plastic pollution during COVID-19 pandemic.