Plant biodiversity is endowed with a huge composition and variability of active molecules known for their therapeutic effects against several diseases. In this current work, several phenolic compounds are subject of in silico evaluation of their interactions with six severe acute respiratory syndrome coronavirus (SARS-CoV) enzymes to evaluate the binding mode and mechanism of phenolic compounds interactions with SARS-CoV-2 enzymes. Results of molecular docking and data analysis revealed that the importance of interactions was dependent to the phenolic class of tested ligand; tannin, biflavone and flavonoid glycoside were the most interactive classes. Among the top three ranked molecules recording lower binding energy against each virus protein target, In conclusion, it was found that Amentoflavone, Dieckol, Bilobetin, Punicalagin, Tellimagrandin-I, Tannic acid, Sciadopitysin, Ginkgetin and Chebulagic acid could be a promising antiviral drug since they present more important binding energy than conventional ones. Their interactions were justified by the Wenn diagram and Ramachandran plot. However, these phenolic compounds recorded an important bioavailability score and found fulfilling most of the drug-likeness criteria such as Lipinski's rule. Clearly, all observations point to further required works aiming to examine more deeply the possibility of using these molecules that could be probably a subject of pre-clinical studies.

Background: The skin is the largest organ of the body and provides the main barrier between the internal and external environment. Assessment of skin permeability is of critical importance for understanding and predicting in vivo efficacy and bioavailability of bioactive phenolic compounds. Objectives: This study investigated the relationship between skin permeability and phenolic compounds using in silico methods. Methods: Screening of skin permeability was performed on 475 randomly selected phenolic compounds. Molecules were expressed in SMILE format downloaded from Phenol-Explorer Database (version 3.6, 2016). Then, their skin permeability was determined by the linear model of the quantitative structure-activity relationship (QSAR). The obtained results were investigated for normal distribution and correlation with pharmacological properties. Results: Our investigation showed that ferulate hydroxycinnamic acid derivatives were the most important phenolic subclass with a permeability of -1.65 cm/s. The relationship between permeability and lipophilicity, water solubility, synthetic accessibility, and bioavailability was evaluated. The statistical analysis revealed that the highest skin permeability was associated with three parameters: the topological polar surface area (TPSA), molecular weight, and lipophilicity (iLog P). Conclusion: The cutaneous permeability depended on several chemical parameters of the molecule used. The classification of phenolic compounds according to their structures proved a wide variability in this permeability.

The leaf essential oil yields of clementine, cypress, rosemary, tea, and thyme were 0.22, 0.87, 1.46, 1.20, and 0.72%, respectively, based on the dry weight of the plant material. The leaf essential oils of rosemary, tea, and thyme contained the highest levels of oxygenated monoterpenes (60.14-91.70%). Rosemary and tea leaf essential oils were rich in 1,8-cineole (49.98% and 57.55%, respectively), and they have potent antifungal activity against Alternaria alternata strain (MIC = 5000 μg/ml). Thyme was rich in carvacrol (78.54%) and had a MIC of 6000 μg/ml against A. alternata strain. Clementine leaf essential oil was characterized by the predominance of monoterpene hydrocarbons (88.65%), and it possessed a weak antifungal activity against A. alternata (MIC = 8000 μg/ml). Cypress leaf essential oil was characterized by the predominance of oxygenated sesquiterpenes (60.67%), having an antifungal activity of 8000 μg/ml.