Flavonoids are now considered as an indispensable component in a variety of nutraceutical and pharmaceutical applications. Most recent researches have focused on the health aspects of flavonoids for humans. Especially, different flavonoids have been investigated for their potential antiviral activities, and several natural flavonoids exhibited significant antiviral properties both in vitro and in vivo. This review provides a survey of the literature regarding the evidence for antiviral bioactivities of natural flavonoids, highlights the cellular and molecular mechanisms of natural flavonoids on viruses, and presents the details of most reported flavonoids. Meanwhile, future perspectives on therapeutic applications of flavonoids against viral infections were discussed.

Δ9-tetrahydrocannabinol (THC) of cannabis is the main psychoactive component which is a global significant concern to human health. Evaluation on THC reported its drastic effect on the brain dopaminergic (DAergic) system stimulating mesolimbic DA containing neurons thereby increasing the level of striatal DA. Cannabidiol (CBD), with its anxiolytic and anti-psychotic property, is potent to ameliorate the THC-induced DAergic variations. Legal authorization of cannabis use and its analogs in most countries led to a drastic dispute in the elicitation of cannabis products. With a recent increase in cannabis-induced disorder rates, the present review highlighted the detrimental effects of THC and the effects of CBD on THC induced alterations in DA synthesis and release. Alongside the reported data, uses of cannabis as a therapeutic medium in a number of health complications are also being briefly reviewed. These evaluated reports led to an anticipation of additional research contradictory to the findings of THC and CBD activity in the brain DAergic system and their medical implementations as therapeutics.

SARS-CoV-2 (2019-nCoV) emerged in 2019 and proliferated rapidly across the globe. Scientists are attempting to investigate antivirals specific to COVID-19 treatment. The 2019-nCoV and SARS-CoV utilize the same receptor of the host which is COVID-19 of the main protease (Mpro).COVID-19 caused by SARS-CoV-2 is burdensome to overcome by presently acquired antiviral candidates. So the objective and purpose of this work was to investigate the plants with reported potential antiviral activity. With the aid of in silico techniques such as molecular docking and druggability studies, we have proposed several natural active compounds including glycyrrhizin, bicylogermecrene, tryptanthrine, β-sitosterol, indirubin, indican, indigo, hesperetin, crysophanic acid, rhein, berberine and β-caryophyllene which can be encountered as potential herbal candidate exhibiting anti-viral activity against SARS-CoV-2. Promising docking outcomes have been executed which evidenced the worthy of these selected herbal remedies for future drug development to combat coronavirus disease.

In Jordan, Salvia ceratophylla L. is traditionally used in the treatment of cancer, microbial infections, and urinary disorders. This study aimed:(1) to chemically characterize S. ceratophylla essential oil (EO) from South Jordan, by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS); and (2) to evaluate in vitro the cytotoxic, anti-inflammatory, and antiprotozoal activities of the EO, it's predominant components, and the hexane (A), ethyl acetate (B), methanol (C) and crude-methanol extracts (D). The analysis revealed that the EO has 71 compounds, with linalool (54.8%) as main constituent. Only the hexane extract (A) showed some cytotoxic activity against SK-MEL, KB, BT-549, SK-OV-3, LLC-PK1 and VERO cells lines with IC 50 between 60 and > 100 μg/mL. The EO inhibited NO production (IC₅₀ 90 μg/mL) and NF-κB activity (IC₅₀ 38 μg/mL). The extracts A, B, and D inhibited NO production and NF-κB activity with IC₅₀ between 32 and 150 μg/mL. Linalool considerably inhibited NO production (IC₅₀ 18 μg/mL). The extracts tested did not exhibit antileishmanial activity. Regarding antitrypanosomal activity, the EO exhibited significant results with IC₅₀ 2.65 μg/mL. In conclusion, Jordan S. ceratophylla EO represents a rich source of linalool and bears a promising therapeutic potential for further antitrypanosomal drug development.

Betulin (BE) can be obtained from many plants, such as those belonging Betulaceae family, and pharmacological investigations showed its notable biological properties and good potential for food and pharmaceutical development. We investigated the homogeneity, stability, purity, and uncertainty of a newly certified reference material (CRM) of BE. The certified purity value for the CRM of BE was 99.56% with an extended uncertainty of 0.07% (k=2, P=0.95), as determined by differential scanning calorimetry (DSC). In this study, DSC was used for the first time for purity determination of BE. Given its high accuracy, precision, and reproducibility, DSC can be used as an alternative technique for purity determination of CRMs in the pharmaceutical and food industry.

Anthraquinone derivatives are identified for their immune-boosting, anti-inflammatory, and anti-viral efficacy. Hence, the present study aimed to investigate the reported anthraquinone derivatives as immune booster molecules in COVID-19 infection and evaluate their binding affinity with three reported targets of novel coronavirus i.e. 3C-like protease, papain-like protease, and spike protein. The reported anthraquinone derivatives were retrieved from an open-source database and filtered based on a positive druglikeness score. Compounds with positive druglikeness scores were predicted for their targets using DIGEPPred and the interaction among modulated proteins was evaluated using STRING. Further, the associated pathways were recorded concerning the Kyoto Encyclopedia of Genes and Genomes pathway database. Finally, the docking was performed using autodock4 to identify the binding efficacy of anthraquinone derivatives with 3C-like protease, papain-like protease, and spike protein. After docking the pose of ligand scoring minimum binding energy was chosen to visualize the ligand-protein interaction. Among 101 bioactives, 36 scored positive druglikeness score and regulated multiple pathways concerned with immune modulation and (non-) infectious diseases. Similarly, docking study revealed torososide B to possess the highest binding affinity with papain-like protease and 3C-like protease and 1,3,6-trihydroxy-2-methyl-9,10-anthraquinone-3-O-(6'-O-acetyl)-β-D-xylopyranosyl-(1 → 2)-β-D-glucopyranoside with spike protein.

Two new 2H-pyran-2-one glucosides, cuscutarosides A (1) and B (2), and one new steroidal glucoside, 7β-methoxy-β-sitosterol 3-O-β-glucopyranoside (3), together with 12 known compounds (4-15) were isolated from the whole plant of Cuscuta reflexa (Convolvulaceae) collected from Myanmar. The chemical structures of these new compounds were elucidated based on extensive spectroscopic analysis. The antiobesity activity of these isolates was evaluated using porcine pancreatic lipase (PPL), and the antiplatelet aggregation activity was screened using rabbit platelets induced by thrombin, plateletactivating factor (PAF), arachidonate (AA), or collagen. 7β-Methoxy-β-sitosterol 3-O-β-glucopyranoside (3) showed weak PPL inhibitory activity. Cuscutaroside A (1), its acetylated derivative (1a), and scrophenoside B (8) showed weak inhibitory activity against rabbit platelet aggregation induced by collagen. Compound 1a also showed inhibitory activity against rabbit platelet aggregation induced by AA.