In silico investigation of phytoconstituents from Cameroonian medicinal plants towards COVID-19 treatment.

In silico studies performed on the metabolites of four Cameroonian medicinal plants with a view to propose potential molecules to fight against COVID-19 were carried out. At first, molecular docking was performed for a set of 84 selected phytochemicals with SARS-CoV-2 main protease (PDB ID: 6lu7) protein. It was further followed by assessing the pharmacokinetics and pharmacological abilities of 15 compounds, which showed low binding energy values. As the screening criteria for their ADMET properties were performed, only two compounds have shown suitable pharmacological properties for human administration which were shortlisted. Furthermore, the stability of binding of these compounds was assessed by performing molecular dynamics (MD) simulations. Based on further analysis through molecular dynamics simulations and reactivity studies, it was concluded that only the Pycnanthuquinone C (17) and the Pycnanthuquinone A (18) extracted from the Pycnanthus angolensis could be considered as candidate inhibitors for targeted protein. Indeed, we expect that these compounds could show excellent in vitro and in vivo activity against SARS-CoV-2. Supplementary information: The online version contains supplementary material available at 10.1007/s11224-022-01939-7.

Cameroonian medicinal plants as potential candidates of SARS-CoV-2 inhibitors.

Coronavirus disease 2019 (COVID-19) is an ongoing pandemic instigated by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) which changed the daily train of the world's population and cause several dead. Despite the significant efforts made in developing vaccines and therapeutic drugs, there is currently no available effective treatment against this new coronavirus infection, hence the need to continue research which is aimed at limiting the progression of this virus. The present study which has as objective to carry out in silico studies on the metabolites of some Cameroonian medicinal plants of the Asteraceae family with a view to propose potential molecules to fight against COVID-19. The selected plants are commonly used to treat respiratory infectious diseases, and for this reason they may contain some constituents which could exhibit an antiviral activity against SARS-CoV-2. In this work, a set of 74 naturally occurring compounds are computed with SARS-CoV-2 main protease protein (PDB ID: 6lu7) and spike protein (PDB ID: 6m0j) for their affinity and stability using binding energy analysis and molecular docking. Chrysoeriol-7-O-ß-D-glucuronopyranoside (compound 16) has showed promising results including excellent Absorption, Distribution, Metabolism and Excretion (ADME) parameters as well as insignificant toxicity. Finally, the stability of this compound is complex with the two proteins validated through molecular dynamics (MD) simulation, they displayed stable trajectory and molecular properties with consistent interaction profile in molecular dynamics simulations. These findings call for further in vitro and in vivo challenges of phytoconstituents against the COVID-19 as a potential agent to fight the spread of this dramatic pandemic.Communicated by Ramaswamy H. Sarma.

Two new triterpenoid saponins: telephiifoliosides A and B from the roots of Corrigiola litoralis subsp. telephiifolia (Pourr.) Briq.

The polar fraction of the MeOH extract of the roots of Corrigiola litoralis subsp. telephiifolia (Pourr.) Briq. (Caryophyllaceae) was investigated for its constituents and two previously unreported monodesmosides triterpene saponins, telephiifoliosides A and B (1 and 2), along with the known bonushenricoside A (3) were isolated. Their structures were elucidated by combined spectroscopic and spectrometric techniques (1H NMR, 13C NMR, HSQC, 1H-1H COSY, HMBC, TOCSY, NOESY, HRESIMS) and chemical methods. The structures of the new saponins were established as; 3-O-α-L-arabinopyranosyljaligonic acid (1), and 3-O-α-L-arabinopyranosylphytolaccagenin ester (2). Upon evaluation of the antiproliferative activity on human malignant epithelial (HeLa) cells, none of the isolated compounds was efficient at the concentration of 33 µM. [Formula: see text]HighlightsThis is the first phytochemical study on Corrigiola litoralis subsp. telephiifolia.Two new saponins were isolated from the roots of Corrigiola litoralis subsp. telephiifolia.The isolated compounds were tested for their antiproliferative activity.