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Hydrogen fluoride (HF) is a highly dangerous and corrosive gas that can cause severe burns and respiratory damage. The density functional theory method (DFT) used to study the interaction between the HF gas and the surface of a carbon nanocone (CNC) doped with gallium atom as a chemical sensor. The results showed that CNC wasn't a good candidate to sense the HF gas and consequently its electrical properties are changed insignificant. To improve the properties of the CNC, several strategies were tried: functionalizing by pyridinol (Pyr) and pyridinol oxide (PyrO), decorated with metals (M = B, Al, and Ga), and doped with element of third group (M = B, Al, and Ga). The obtained data demonstrated that the promising results were obtained by doping the CNC with Ga atom. After full optimization, we achieved one stable configuration between the HF gas and CNC-Ga structure (S15 configuration) with E ads = −19.86 kcal/mol. The electronic properties of the CNC-Ga structure is sensible changed after the HF molecule is adsorbed. According to calculated the energy gap between HOMO and LUMO orbitals of S15 configuration are increased which could be applied a chemical signal. Eventually, one could propose that the CNC-Ga has the ability to act as a Φ-type sensor based on its physical adsorption energy and quick recovery time and doped with gallium atom is a promising strategy. [Display omitted] • Pristine CNC isn't a good candidate to sense the HF gas. • Several strategies containing 1) functionalized 2) decorated and 3) doped strategies for possible sensing of HF. • One stable configuration between the HF gas and the CNC-Ga structure with Eads = −19.86 kcal/mol was formed. • The CNC-Ga can be played as an Φ-type sensor due to physical adsorption energy and low recovery time. [ABSTRACT FROM AUTHOR]

Owing to the shortage of specific medicines, the global pandemic of COVID-19 caused by SARS-CoV-2 has been the greatest challenge for the science community. Researchers from all over the world developed some drugs which failed to completely suppress the contiguous disease. SARS-CoV-2 main protease (Mpro), an important component in viral pathogenesis, is considered as a prospective drug target to stop SARS-CoV-2 infection. Since identification of phytochemicals with anti-Mpro activity has been carried out to develop the potential drugs against SARS-CoV-2. Therefore, the present study was conducted to screen phytochemicals of Berberis asiatica for anti-SARS-CoV-2 activity. Through text mining, thirty phytochemicals were reported from B. asiatica, of which, three phytochemicals (Berbamine, Oxyacanthine, and Rutin) show high affinity with the SARS-CoV-2 Mpro and exhibited favorable intermolecular interactions with the catalytic residues (His41 and Cys145) and other essential residues. The molecular dynamics simulation showed that Mpro-phytochemical complexes are more stable, less fluctuating, more compact, and moderately extended than the Mpro-X77 (Reference) complex. The number of H-bonds and MMPBSA results also demonstrates that Berbamine, Oxyacanthine, and Rutin are potent Mpro inhibitors having free energy of −20.79, −33.35, and −31.12 kcal mol−1 respectively. The toxicity risk prediction supports all phytochemicals for drug-like and non-toxic nature. From the result, we propose that binding of these phytochemicals could hamper the function of Mpro. This work suggests that selected phytochemicals could be used as novel anti-COVID-19 drug candidates, and might act as novel compounds for in vitro and in vivo study. [Display omitted] • Screening of drug candidates against the global pandemic of Covid-19. • Use of SARS-CoV-2 main protease (Mpro) as a prospective drug target. • Screening of B. asiatica phytochemicals as inhibitors of SARS-CoV-2 Mpro by molecular docking. • MD simulation and MMPBSA show Berbamine, Oxyacanthine, and Rutin as novel drug candidates against SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Tuberculosis remains the cause of mortality throughout the world. Currently, the available anti-tubercular drugs are not effective because of the existence of Multi-Drug resistant tuberculosis (MDR-TB) and Extensively-Drug resistant tuberculosis (XDR-TB). It has, therefore, become necessary to develop novel drugs that inhibit the activity of drug-resistant Mycobacterium tuberculosis. Due to the existence of MDR and XDR-TB, Mtb Ag85C has risen out as a propitious molecular drug target as it has importance in the synthesis of main components of the Mtb cell envelope which are essential for the virulence and survival of Mtb. In a previous paper, we studied a potential drug target by virtual high throughput screening of compounds and in continuation of the study on Mtb Ag85C, we further studied the role of lichen compounds in the inhibition of Ag85C. In the current research work, virtual screening of a lichen compounds library was performed against Ag85C. Further, ADMET analysis was employed to filter out the screened lichen compounds. Bioactivity score and toxicity prediction finalized four lichen compounds i.e. Portentol, Aspicilin, Parietinic acid and Polyporic acid as potential inhibitors of Ag85C. The stability and dynamic behavior of four compounds were analyzed by using Molecular dynamics simulation which indicated that they may be potential inhibitors of Ag85C. Therefore, based on the above results, Portentol, Aspicilin, Parietinic acid and Polyporic acid may be potential drug candidates against Mtb. We suggest that the use of these compounds can minimize the treatment time-period and the various side effects associated with the currently available anti-tubercular drugs. Image 1 • Existence of drug-resistant tuberculosis is the main failure of currently available anti-tubercular drugs. • Ag85C is a propitious molecular drug target that has importance in the biosynthesis of Mtb cell wall. • Screening and identification of lichen compounds as inhibitors of Ag85C. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is a deadly disease which causes millions of death annually worldwide. Although TB is treatable but the rise of cases of multidrug-resistant and totally drug-resistant strains of Mycobacterium tuberculosis (Mtb) poses a great challenge to cure TB completely and this situation demands an urgent need for development of potential anti-tubercular drugs. In this regard, the antigen 85C (Ag85C) has emerged as an essential mycobacterial drug target as it plays a central role in synthesizing major components of the inner and outer layers of outer membrane of Mtb. In this research, we have identified four novel potential inhibitors as a potent inhibitor of the Mtb Ag85C from CHEMBL24, MolPort, Zinc and PubChem library by High Throughput Virtual Screening. The results of molecular dynamics show that these compounds bind to Ag85C protein with high stability. The ADMET profiling and pharmacophore analysis indicate that these compounds may act as potential anti-mycobacterial candidates. On the basis of findings our work, we propose that these compounds are novel potential inhibitors of Mtb Ag85C with similar or better properties than the classic inhibitor and they can potentially shorten the treatment duration and may have anti-mycobacterial activity against drug-resistant Mtb strains. (Flow chart showing steps for screening the inhibitors of mycolyltransferase Mtb Ag85C). Image 1 • Targeting antigen 85C (Ag85C) to inhibit cell wall biosynthesis of Mycobacterium tuberculosis. • Pharmacophore Model development and virtual screening of compounds. • ADMET, Bioactivity score and Toxicity prediction. • Molecular Dynamics Simulation and MM-PBSA analysis. [ABSTRACT FROM AUTHOR]