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Since the emergency of coronavirus disease 2019, no specific drug has been developed within the fighting program against its spread. In Cameroon, it has been reported that the dish “yellow soup” can significantly curb the progress of the disease, while no chemical investigations have been done so far to support that conclusion. Chemical investigations of four selected spices of that dish led to the isolation of a total of 44 distinct pure compounds, which were identified using spectroscopic data. Furthermore, the docking scores of the isolated compounds were inspected by AutoDock4.2.6 software toward SARS-CoV-2 multi-targets involving main protease (Mpro), helicase, papain-like protease (PLpro), and human angiotensin‐converting enzyme 2 (ACE2). The most potent isolated compounds underwent molecular dynamics (MD) simulations over 100 ns. Stigmasterol demonstrated outstanding potency toward Mpro and PLpro with ΔG binding values of −35.6 and −36.6 kcal/mol, respectively, compared to nirmatrelvir. Nevertheless, 3β-taraxeryl acetate revealed good binding affinity against helicase and lupeol unveiled superior binding energy toward ACE2 compared to nirmatrelvir. Post-MD analyses manifested great steadiness of the isolated compounds within the binding pockets of SARS-CoV-2 targets throughout 100 ns MD simulations. Stigmasterol, 3β-taraxeryl acetate, and lupeol are recommended for further in vivo/in vitro tests toward SARS-CoV-2 multi-targets.

The phytochemical investigation of the methanol extract of the stem bark of Chrysophyllum lacourtianum led to the isolation and characterization of one new secondary metabolite, lacourtianal (1), together with eight known compounds. Compounds 2; 3; 5; 6; 7 and 9 were reported for the first time from Chrysophyllum genus. The structures of compounds 1–9 were elucidated on the basis of 1 D and 2 D NMR spectroscopic and mass spectrometric data as well as comparison with the literature. The antibacterial activity of the methanol extract, fractions and compounds 1–9 were evaluated against bacterial strains. The methanol extract exhibited moderate activity against Staphylococcus aureus NR4674 with MIC values of 500 µg/mL. The n-hexane fraction showed moderate activity against Staphylococcus aureus (ATCC 43300 and ATCC 25923) with MIC values of 125 µg/mL and ursolic acid (5) exhibited strong activity against Enterobacter aerogenes CPC and Escherichia coli ATCC 25322 with MIC values of 7.8 and 3.9 µg/mL respectively. [ABSTRACT FROM AUTHOR]

Stem barks of Boswellia dalzielii are used traditionally for the treatment of various bacterial infections. A bioassay guided fractionation of the MeOH-CH2Cl2 (1/1, v/v) stem barks extract led to the isolation of fourteen compounds 1–14, identified based on spectroscopic data. Dalzienoside (1) is reported here for the first time. The broth microdilution method was used to evaluate the antibacterial activity of the crude extract, fractions and compounds against six bacterial strains. The crude extract exhibited moderate antibacterial activity with MIC of 250 μL/ml; two fractions showed significant activities with MICs ranging from 7.8 to 125 μg/ml, while α-boswellic acid (2), β-boswellic acid (3), acetyl-11-keto-β-boswellic acid (4) from these fractions exhibited strong activities with MIC value of 3.125 µg/mL against Staphylococcus aureus, Salmonella typhi, Enterobacter cloacae, Streptococcus pneumonia and Pseudomonia aeruginosa. This study gives insight into the antibacterial constituents of the stem bark of B. dalzielii and justifies its use in ethnomedicine. [ABSTRACT FROM AUTHOR]

To the best of our knowledge, this is the first chemical study of Guarea glomerulata that led to the isolation and characterisation of nine distinct compounds from its methanolic leaves extract including one new trinortriterpenoid glomerulatin along with eight known compounds amongst which five compounds namely azadirone, oleanolic acid, sericoside, cleomiscosin D and griffonin reported for the first time from the genus Guarea . All the isolated compounds have been evaluated in vitro for their antiplasmodial potency against the chloroquine-sensitive strain P. falciparum 3D7. The results showed that glomerulatin and azadirone were the most active compounds with IC 50 values of 1.02 ± 0.2  μ M and 1.48 ± 0.4  μ M, respectively. This study enriches the chemistry of the genus Guarea and further supports the identification of Meliaceae plants as a good source of antiplasmodial candidates for the development of new potent drugs against malaria.

Chemical investigations of a methanolic extract of the twigs of Vernonia amygdalina Delile (Asteraceae) resulted in the isolation and identification of three previously undescribed highly oxygenated Δ 7,9(11) stigmastane-type steroids namely vernonins U-W (1-3) along with six known compounds (4-9). The structural characterization of all the isolated compounds has been conducted via comprehensive 1D and 2D-NMR spectroscopy as well as HRMS. The seven steroidal derivatives 1-7 were evaluated for their antiplasmodial activity against the chloroquine-resistant strain P. falciparum Dd2 (PfDd2) and their hemolytic effect on human red blood cells (RBCs). Vernonins U (1), A (4) and stigmasterol-3-O-β-d-glucopyranoside (7) showed the highest activity with IC 50 values of (5.47 ± 0.01) μg/mL, (6.02 ± 0.13) μg/mL and (6.34 ± 0.80) μg/mL, respectively, against PfDd2, while vernonin W (3) showed moderate activity of (21.20 ± 0.40) μg/mL. None of the tested compounds displayed hemolytic effects on human RBCs up to 100 μg/mL indicating their safety. These results enrich the known chemistry of V. amygdalina and support its use in folk medicine for the treatment of malaria. This encourages further research towards new antiplasmodial drug candidates from this plant., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)