6-shogaol for COVID-19

Abstract Aims The aim of the present review was to highlight natural product investigations in silico and in vitro to find plants and chemicals that inhibit or stimulate angiotensin-converting enzyme 2 (ACE-2). Background The global reduction of incidents and fatalities attributable to infections with SARS-CoV-2 is one of the most public health problems. In the absence of specific therapy for coronavirus disease 2019 (COVID-19), phytocompounds generated from plant extracts may be a promising strategy worth further investigation, motivating researchers to evaluate the safety and anti-SARS-CoV-2 effectiveness of these ingredients. Objective To review phytochemicals in silico for anti-SARS-CoV-2 activity and to assess their safety and effectiveness in vitro and in vivo. Methods The present review was conducted using various scientific databases and studies on anti-SARS-CoV-2 phytochemicals were analyzed and summarized. The results obtained from the in silico screening were subjected to extraction, isolation, and purification. The in vitro studies on anti-SarcoV-2 were also included in this review. In addition, the results of this research were interpreted, analyzed, and documented on the basis of the bibliographic information obtained. Results This review discusses recent research on using natural remedies to cure or prevent COVID-19 infection. The literature analysis shows that the various herbal preparations (extracts) and purified compounds can block the replication or entrance of the virus directly to carry out their anti-SARS-CoV-2 effects. It is interesting to note that certain items can prevent SARS-CoV-2 from infecting human cells by blocking the ACE-2 receptor or the serine protease TMPRRS2. Moreover, natural substances have been demonstrated to block proteins involved in the SARS-CoV-2 life cycle, such as papain- or chymotrypsin-like proteases. Conclusion The natural products may have the potential for use singly or in combination as alternative drugs to treat/prevent COVID-19 infection, including blocking or stimulating ACE-2. In addition, their structures may provide indications for the development of anti-SARS-CoV-2 drugs.

Since the outbreak of the COVID-19 (coronavirus disease 19) pandemic, researchers have been trying to investigate several active compounds found in plants that have the potential to inhibit the proliferation of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). The present study aimed to evaluate bioactive compounds found in plants using a molecular docking approach to inhibit the main protease (Mpro) and spike (S) glycoprotein of SARS-CoV-2. The evaluation was performed on the docking scores calculated using AutoDock Vina (AV) as a docking engine. A rule of five (Ro5) was calculated to determine whether a compound meets the criteria as an active drug orally in humans. The determination of the docking score was performed by selecting the best conformation of the protein-ligand complex that had the highest affinity (most negative Gibbs’ free energy of binding/ <math xmlns="http://www.w3.org/1998/Math/MathML" id="M1"> <mi mathvariant="normal">Δ</mi> <mi>G</mi> </math> ). As a comparison, nelfinavir (an antiretroviral drug), chloroquine, and hydroxychloroquine sulfate (antimalarial drugs recommended by the FDA as emergency drugs) were used. The results showed that hesperidin, nabiximols, pectolinarin, epigallocatechin gallate, and rhoifolin had better poses than nelfinavir, chloroquine, and hydroxychloroquine sulfate as spike glycoprotein inhibitors. Hesperidin, rhoifolin, pectolinarin, and nabiximols had about the same pose as nelfinavir but were better than chloroquine and hydroxychloroquine sulfate as Mpro inhibitors. This finding implied that several natural compounds of plants evaluated in this study showed better binding free energy compared to nelfinavir, chloroquine, and hydroxychloroquine sulfate, which so far are recommended in the treatment of COVID-19. From quantum chemical DFT calculations, the ascending order of chemical reactivity of selected compounds was pectolinarin &gt; hesperidin &gt; rhoifolin &gt; morin &gt; epigallocatechin gallate. All isolated compounds’ C=O regions are preferable for an electrophilic attack, and O-H regions are suitable for a nucleophilic attack. Furthermore, Homo-Lumo and global descriptor values indicated a satisfactory remarkable profile for the selected compounds. As judged by the RO5 and previous study by others, the compounds kaempferol, herbacetin, eugenol, and 6-shogaol have good oral bioavailability, so they are also seen as promising candidates for the development of drugs to treat infections caused by SARS-CoV-2. The present study identified plant-based compounds that can be further investigated in vitro and in vivo as lead compounds against SARS-CoV-2.

Abstract Coronavirus disease (COVID-19) pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARSCoV-2). Although many vaccines have been developed against the virus, problems associated with vaccine resistance, vaccine apathy and the evolution of variants of the virus with increased transmissibility calls for the development of more effective and affordable drugs to combat the disease. Natural source drugs are regarded as an essential part of the therapy regimen for COVID-19 treatment and other viral respiratory infections as such needs to be exploited for the treatment of the virus globally. The study aimed to computationally screen the phytochemicals of some Nigerian plants used in the therapy of common cold for anti-COVID-19 activity. Phytochemical analysis of the plant extracts was performed employing standard techniques, while Gas chromatography–mass spectrometry was used to detect the bioactive compounds present in the extracts. The selected plant bioactive compounds were docked against the SARS-CoV-2 Main protease (Mpro), RNA-dependent RNA polymerase (RdRp), and S protein-ACE2 targets, while Lopinavir, Remdesivir and Favipiravir were included as standard ligands. The phytochemical constituents of the extracts were steroids, flavonoids, saponins, tannins, phenols, glycosides, terpenoids, and alkaloids. All the bioactive compounds exhibited acceptable drug-likeness and good oral bioavailability prediction, in addition to 89% of the compounds having slightly or practically non-oral toxicity using SwissADME and ProTox-II prediction servers. The overall result suggested that 3-Epimoretenol, Beta-Amyrin acetate, Methyl 3-oxours-12-en-23-oate, 20(29)-Lupenol acetate and Lanosterol acetate are the top most promising therapeutic bioactive natural compounds with antiviral activity against the SARS-CoV-2 Mpro, RdRp and spike protein when compared to standard drugs. Taken together, data obtained reveal that these bioactive natural compounds may have a very good potential as anti-COVID-19 therapy.