Plants as a Prospective Source of Natural Anti-viral Compounds and Oral Vaccines Against COVID-19 Coronavirus

Abstract

The proposal of novel drugs and approaches for effective treatment of the novel coronavirus is a necessity after the quick outbreak of the disease. Since the commencement of the coronavirus spread, enormous efforts have been made to protect, alleviate and cure the disease, though no specific treatment has been approved. While there have been convincing results in the use of chemical drugs and interferon therapy, such therapeutic approaches have various drawbacks and lack the required performance for the treatment of the new coronavirus. Medicinal plant species can provide a solution as a source of natural antiviral compounds by the accumulation of secondary metabolites and lectins as well as acting as a platform to express the viral immunogenic proteins. This study reviews the advantages and the results of previous research for the treatment of the novel coronavirus disease and previous generations of similar coronaviruses. Several plant-derived anti coronavirus compounds have been nominated that could be targeted for further research due to the similarity of the coronavirus disease in 2003 and the current coronavirus. This review regards plant species such as Scutellaria baicalensis (Baikal skullcap), and Utrica dioica (Stinging nettle) as suitable candidates for the new coronavirus antiviral research. Furthermore, the use of plants such as Nicotiana tabacum (Tobacco) for the expression of the coronavirus viral antigens can be a target for the future vaccinal research of the new coronavirus due to the efficiency of expression and intrinsic antiviral properties.

Potentials of plant-based substance to inhabit and probable cure for the COVID-19

“…Lectins, the carbohydrate-binding proteins from Nicotiana tabacum, Allium porrum, and Utrica dioica were found to be significantly potential for slowing down the viral invasion and propagation to 50% (EC50) after applying the inhibitory concentrations (less than 1.3 µg/ mL) of pure extract of lectins (Yonesi and Rezazadeh, 2020). These compounds are the defense proteins in plants that can perform like immunologic receptors, and therefore could be marked for treating COVID-19 patients.…”

In silico molecular docking studies and ADME/T analysis of Some Flavonoids against the target of Mpro inCOVID-19

“…it's been con irmed that the PLPro and 3CLPro of the SARS-Cov and SARS-Cov2 are conserved. [8] Additionally, it's observed that there's a 76.10% identity between the mentioned viruses. Supported, it's expected that the results of the studies about the SARS-Cov might imply for research within the SARS-Cov2 to a high degree.…”

Plant-Derived Secondary Metabolites as Potential Mediators against COVID-19: A Review

“…Plant"s immunity is a highly sophisticated system that can efficiently notice and disable the invading pathogens by a variety of tackles using intracellular receptor proteins. Many plant secondary metabolites are known to inhibit the effects of specific enzyme proteins essential for the propagation of different viruses (Yonesi & Rezazadeh, 2020). The essential oils targeting lipid-envelop and the polyphenols targeting viral protein are active against free viruses whereas the intercalating alkaloids inhibit the replication of viruses inside the host cell.…”