All the plants and their secondary metabolites used in the present study were obtained from Ayurveda, with historical roots in the Indian subcontinent. The selected secondary metabolites have been experimentally validated and reported as potent antiviral agents against genetically-close human viruses. The plants have also been used as a folk medicine to treat cold, cough, asthma, bronchitis, and severe acute respiratory syndrome in India and across the globe since time immemorial. The present study aimed to assess the repurposing possibility of potent antiviral compounds with SARS-CoV-2 target proteins and also with host-specific receptor and activator protease that facilitates the viral entry into the host body. Molecular docking (MDc) was performed to study molecular affinities of antiviral compounds with aforesaid target proteins. The top-scoring conformations identified through docking analysis were further validated by 100 ns molecular dynamic (MD) simulation run. The stability of the conformation was studied in detail by investigating the binding free energy using MM-PBSA method. Finally, the binding affinities of all the compounds were also compared with a reference ligand, remdesivir, against the target protein RdRp. Additionally, pharmacophore features, 3D structure alignment of potent compounds and Bayesian machine learning model were also used to support the MDc and MD simulation. Overall, the study emphasized that curcumin possesses a strong binding ability with host-specific receptors, furin and ACE2. In contrast, gingerol has shown strong interactions with spike protein, and RdRp and quercetin with main protease (Mpro) of SARS-CoV-2. In fact, all these target proteins play an essential role in mediating viral replication, and therefore, compounds targeting aforesaid target proteins are expected to block the viral replication and transcription. Overall, gingerol, curcumin and quercetin own multitarget binding ability that can be used alone or in combination to enhance therapeutic efficacy against COVID-19. The obtained results encourage further in vitro and in vivo investigations and also support the traditional use of antiviral plants preventively.

The primary objective of this study is to conduct a comprehensive review of the significance of molecular docking in the field of drug discovery. This includes an examination of the various approaches and methods used in molecular docking, as well as an exploration of the techniques used for interpreting and validating docking results. To gather relevant data, a systematic search was conducted using Web of Science, PubMed, and Google Scholar. The search focused on articles related to molecular docking methodologies and their applications in drug discovery. Additionally, alternative techniques that can be used for more precise simulations of ligand-protein interactions were also considered. Molecular docking has proven to be an incredibly rich and valuable process in the field of drug discovery. Its flexibility allows for the incorporation of advanced computational techniques, thereby enhancing the reliability and efficiency of drug discovery processes. The results of the study highlights the significant strides made in the field of molecular docking, demonstrating its potential to revolutionize drug discovery. Molecular docking continues to evolve, with new advancements being made regularly. Despite the challenges faced, these advancements have significantly contributed to the enhancement of molecular docking, solidifying its position as a crucial tool in the field of drug discovery.

We report electric-field-induced modulation of the spin splitting during the charging and discharging processes of a $p$-type $\mathrm{GaAs}∕\mathrm{AlAs}$ double-barrier resonant-tunneling diode under an applied bias and magnetic field. In addition to the conventional Zeeman effect, we find experimental evidence of excitonic spin splitting produced by a combination of the Rashba spin-orbit interaction, the Stark effect, and the charge accumulation. The abrupt changes in the photoluminescence with the applied bias provide information about charge accumulation effects in the device.