ABSTRACT
The coronavirus disease 2019 (COVID-19) is caused by the recently discovered coronavirus and affects several countries worldwide. Some medications may alleviate or minimize some of the disease symptoms, but no drug have been proven to prevent or cure it. However, this study was aimed at investigating the role of some medicinal plants as potent inhibitors of COVID-19 main protease (MPro). More than 250 plant extracts with antiviral activity were exploited for their potential SARS-CoV2 medication using molecular docking. The conformational stability of the compounds extracted from the plants with MPro interactions was evaluated using molecular dynamics simulations. Then, the plant extracts with the highest binding energies were used for treatments by administering them to 50 COVID-19 patients, while the other 50 cases received only the drug without the plant extracts. The results of the theoretical analysis revealed high binding energies for seven compounds. Alliin stabilized COVID-19’s MPro while retaining critical connections and remained stable throughout the simulations. Marrubin and thymoquinone are also capable of protein stabilization over the simulated time. The test plants were observed to be effective against the virus in the COVID-19 patients, with a disease symptom improvement response rate of 78-86 and 60-72% for the first and second groups, respectively. Also, the percentage of oxygen increased from the second day after taking the extracts. Ground-glass opacity disappeared from the second group that received the plant extracts. The findings of this study suggest that these compounds have a great potential for therapeutic activity if isolated and administered alone.
ABSTRACT
The outbreak of viral pneumonia caused by the novel coronavirus SARS-CoV-2 that began in December 2019 caused high mortality. It has been suggested that the main protease (Mpro) of SARS-CoV-2 may be an important target to discover pharmaceutical compounds for the therapy of this life-threatening disease. Remdesivir, ritonavir and chloroquine have all been reported to play a role in suppressing SARS-CoV-2. Here, we applied a molecular docking method to study the binding stability of these drugs with SARS-CoV-2 Mpro. It appeared that the ligand-protein binding stability of the alliin and SARS-CoV-2 Mpro complex was better than others. The results suggested that alliin may serve as a good candidate as an inhibitor of SARS-CoV-2 Mpro. Therefore, the present research may provide some meaningful guidance for the prevention and treatment of SARS-CoV-2.