SARS-CoV-2, the viral particle, is responsible for triggering the 2019 Coronavirus disease outbreak (COVID-19). To tackle this situation, a number of strategies are being devised to either create an antidote, a vaccine, or agents capable of preventing its infection. To enable research on these strategies, numerous target proteins are identified where Spike (S) protein is presumed to be of immense potential. S-protein interacts with human angiotensin-converting-enzyme-2 (ACE2) for cell entry. The key region of S-protein that interacts with ACE2 is a portion of it designated as a receptor-binding domain (RBD), following whereby the viral membrane fuses with the alveolar membrane to enter the human cell. The proposition is to recognise molecules from the bundle of phytochemicals of medicinal plants known to possess antiviral potentials as a lead that could interact and mask RBD, rendering them unavailable to form ACE2 interactions. Such a molecule is called the 'S-protein blocker’. A total of 110 phytochemicals from Withania somnifera , Asparagus racemosus, Zinziber officinalis , Allium sativum , Curcuma longa and Adhatoda vasica were used in the study, of which Racemoside A, Ashwagandhanolide, Withanoside VI, Withanoside IV and Racemoside C were identified as top five hits using molecular docking. Further, essential Pharmacophore features and their ADMET profiles of these compounds were studied following to which the best three hits were analyzed for their interaction with RBD using Molecular Dynamics (MD) simulation. Binding free energy calculations were performed using MM/GBSA, proving these phytochemicals can serve as S-protein blocker.

Novel SARS-CoV-2, an etiological factor of Coronavirus disease 2019 (COVID-19), poses a great challenge to the public health care system. Among other druggable targets of SARS-Cov-2, the main protease (Mpro) is regarded as a prominent enzyme target for drug developments owing to its crucial role in virus replication and transcription. We pursued a computational investigation to identify Mpro inhibitors from a compiled library of natural compounds with proven antiviral activities using a hierarchical workflow of molecular docking, ADMET assessment, dynamic simulations and binding free-energy calculations. Five natural compounds, Withanosides V and VI, Racemosides A and B, and Shatavarin IX, obtained better binding affinity and attained stable interactions with Mpro key pocket residues. These intermolecular key interactions were also retained profoundly in the simulation trajectory of 100 ns time scale indicating tight receptor binding. Free energy calculations prioritized Withanosides V and VI as the top candidates that can act as effective SARS-CoV-2 Mpro inhibitors.

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Aim of this study is to analyse the regression correlation between GBH and Carbon stock in the major tree species of Dharoi Range, Gandhinagar Forest Division. Major ten dominant tree species in Dharoi range were selected for study. Total biomass and carbon sequestered in the major tree species have been estimated using nondestructive method. Based on this analysis and interpretation the allometric model is prepared which will be helpful to estimate carbon stock of major tree species by Girth at Breast Height (GBH). Species like Anogeissus pendula Edgew, Acacia tortilis (Forsk) Hyne and Wrightia tinctoria R Br were dominant while Bauhinia racemosa Lam, Butea monosperma (Lam) Taub less in number. The maximum carbon stock estimated in Acacia tortilis (Forsk) Hyne, Anogeissus pendula Edgew, and Wrightia tinctoria R Br whereas Bauhinia racemosa Lam, Butea monosperma (Lam) Taub showed least carbon stock. On the basis of analysis the regression correlation between GBH and Carbon Stock is linear in Dharoi range for major tree species. On the basis of study following species showed a deviation from the correlation viz, Butea monosperma (Lam) Taub having very small ratio while Azadirachta indica A Juss having a very large ratio in the range. This shows that the species which having small ratio are poorly adapted to that particular ranges while the species shows large ratio are very well adapted to this range. The results are discussed in the context of their adaptive significance and use in determining suitability of the tree species for afforestation, forest regeneration and establishment of shelter belts to arrest deforestation.

The novel SARS-CoV-2 is an etiological factor that triggers Coronavirus disease in 2019 (COVID-19) and tends to be an imminent occurrence of a pandemic. Out of all recognized solved complexes linked to SARS-CoV, Main protease (Mpro) is considered a desirable antiviral phytochemical that play a crucial role in virus assembly and possibly non-interactive capacity to adhere to any viral host protein. In this research, SARS-CoV-2 MPro was chosen as a focus for the detection of possible inhibitors using a variety of different analytical methods such as molecular docking, ADMET analysis, dynamic simulations and binding free energy measurements. Virtual screening of known natural compounds recognized Withanoside V, Withanoside VI, Racemoside B, Racemoside A and Shatavarin IX as future inhibitors of SARS-CoV-2 MPro with stronger energy binding. Also, simulations of molecular dynamics for a 100 ns time scale showed that much of the main SARS-CoV-2 MPro interactions had been maintained in the simulation routes. Binding free energy calculations using the MM/PBSA method ranked the top five possible natural compounds that can act as effective SARS-CoV-2 MPro inhibitors.