The expansion of the novel coronavirus known as SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), COVID-19 (coronavirus disease 2019), or 2019-nCoV (2019 novel coronavirus) is a global concern over its pandemic potential. The need for therapeutic alternatives to stop this new pandemic is urgent. Nowadays, no efficacious therapy is available, and vaccines and drugs are underdeveloped to cure or prevent SARS-CoV-2 infections in many countries. Some vaccines candidates have been approved; however, a number of people are still skeptical of this coronavirus vaccines. Probably because of issues related to the quantity of the vaccine and a possible long-term side effects which are still being studied. The previous pandemics of infections caused by coronavirus, such as SARS-CoV in 2003, the Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012, HCoV-229E, and HCoV-OC43 were described in the 1960 s, -HCoV-NL63 isolated in 2004, and HCoV-HKU1identified in 2005 prompted researchers to characterize many compounds against these viruses. Most of them could be potentially active against the currently emerging novel coronavirus. Five membered nitrogen heterocycles with a triazole, imidazole, and thiazole moiety are often found in many bioactive molecules such as coronavirus inhibitors. This present work summarizes to review the biological and structural studies of these compound types as coronavirus inhibitors.

This study focuses on the synthesis of silver nanoparticles (AgNPs) using the extract of Aphania senegalensis leaves. The extraction was done using maceration at room temperature in water for 48 h. The synthesized nanoparticles were characterized by IR, XRD, TEM, and SEM. The thermal stability of these nanoparticles was studied by TGA. The zeta potential was used to define the size, charge distribution, and stability of the nanoparticles. Optimization reactions were carried out based on reaction time, pH, and temperature. The nanoparticles obtained from optimal conditions were evaluated on induced inflammation. The determination of the average diameters and geometry of nanoparticles was carried out by XRD by calculating the lattice constants, and they are between 18.11 and 50 nm. The evaluation of anti‐inflammatory activity showed that the nanoparticles are 10 times more active than the extract of Aphania senegalensis leaves. Minimum doses of 10 mg/kg orally and 3 mg/kg were obtained for the plant extract, respectively. These results are promising for the possibility of AgNPs to be used for the treatment of inflammation.

Amaryllidaceae plants are rich in alkaloids with biological properties. Pancratium trianthum is an Amaryllidaceae species widely used in African folk medicine to treat several diseases such as central nervous system disorders, tumors, and microbial infections, and it is used to heal wounds. The current investigation explored the biological properties of alkaloid extracts from bulbs of P. trianthum collected in the Senegalese flora. Alkaloid extracts were analyzed and identified by chromatography and mass spectrometry. Alkaloid extracts from P. trianthum displayed pleiotropic biological properties. Cytotoxic activity of the extracts was determined on hepatocarcinoma Huh7 cells and on acute monocytic leukemia THP-1 cells, while agar diffusion and microdilution assays were used to evaluate antibacterial activity. Antiviral activity was measured by infection of extract-treated cells with dengue virus (DENV_GFP) and human immunodeficiency virus-1 (HIV-1_GFP) reporter vectors. Cytotoxicity and viral inhibition were the most striking of P. trianthum’s extract activities. Importantly, non-cytotoxic concentrations were highly effective in completely preventing DENV_GFP replication and in reducing pseudotyped HIV-1_GFP infection levels. Our results show that P. trianthum is a rich source of molecules for the potential discovery of new treatments against various diseases. Herein, we provide scientific evidence to rationalize the traditional uses of P. trianthum for wound treatment as an anti-dermatosis and antiseptic agent.

The study aimed to investigate the chemical composition and antimicrobial and antioxidant activities of the essential oil from dried seeds of Xylopia aethiopica. The essential oil was obtained by hydrodistillation and analyzed by GC/FID and GC/MS. The essential oil yield was 1.35. Forty-nine compounds were identified in the essential oil with 1,8-cineole (16.3), β-pinene (14.8), trans-pinocarveol (9.1), myrtenol (8.3), α-pinene (5.9), and terpinen-4-ol (5.6) as major components. The antimicrobial activity of this essential oil was studied using disk diffusion and broth microdilution methods on four bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa) and one fungus (Candida albicans). The essential oil exhibited excellent activity against S. aureus, E. faecalis, and C. albicans and moderate activity against E. coli. Among all strains tested, C. albicans showed the best sensitivity with a MIC of 50mg/mL. The antioxidant activity was examined using a DPPH-free radical scavenging assay. The essential oil of X. aethiopica showed low antioxidant activity (IC₅₀=784.604±0.320mg/mL) compared to that of ascorbic acid and the reference compound (IC₅₀=0.163±0.003mg/mL). The results indicate that consumption of X. aethiopica seeds can reduce the virulence of food-borne pathogens and their resistance to antibiotics.

The phytochemical screening showed that the Moringa oleifera (MO) extract contained many compounds such as polyphenols, polyterpenes, sterols, reducing sugars, and hydrolysates tannins. The MICs of MO extract for microbial strains is 0.73 mg/ml for Escherichia coli, Pseudomonas aeruginosa, 7.5 mg/ml for Enterococcus faecalis, Staphylococcus aureus and 0.5 mg/ml for Candida albicans. The MO extract has an IC₅₀ of 3.403 mg/ml has an antioxidant activity by DPPH radical scavenging. The cytotoxic activity of MO extract was evaluated by determining the content of lactate dehydrogenase released by the lysed cells. MO extract exhibited cytotoxic activity against HeLa and FaDu cell lines with an identical IC₅₀ value of 25 µg/ml. We did not observe any remarkable decrease cytotoxic activity when these lines were exposed to the MO extract after 48 h. Our findings help to support the promising role of MO as anticancer agent and open a new challenge for studying DNA fragmentation.