Would carvacrol be a supporting treatment option effective in minimizing the deleterious effects of COVID-19?

Herbal Medicine in Three Different Mediterranean Living Areas During the COVID-19 Pandemic: The Role of Polyphenolic-Rich Thyme-like Plants

Despite herbal medicine being popular across the Mediterranean basin, there is no evidence in favor of COVID-19 infection. This study investigates the utilization and effects of medicinal plants in Italy, Lebanon, and Tunisia during COVID-19 and its effects on post-COVID-19 pandemics. We used a tailored, web-based "Google Form" questionnaire with the random sampling method. We gathered 812 complete responses (Italy: 116, Lebanon: 557, and Tunisia: 139), revealing diverse demographics and symptom experiences. Fatigue prevailed across all groups (89.0-94.2%), while psychological impacts ranged from 20.1% to 30.9%, with higher rates in Lebanon. Post-COVID-19 symptoms affected 22.4% (Italy), 48.8% (Lebanon), and 31.7% (Tunisia). General use of herbs was consistent (41.4-50.4%), with 23.3% (Italy), 50.2% (Lebanon), and 65.5% (Tunisia) employing herbs for COVID-19 therapy. Notably, in Lebanon, Za'atar, a thyme-like plant, correlated with reduced symptoms, suggesting potential protective effects that are likely due to its polyphenol richness. This study underscores the persistent reliance on traditional medicinal plants remedies in the Mediterranean area, with regional variations. Further exploration of herbal compounds for COVID-19-like symptoms is warranted.

Molecular insights into binding of bioactive compounds from essential oil of Trachyspermum ammi with human programmed cell death protein 1

The human programmed cell death protein 1 (PD-1) is expressed on the surface of T cells and contributes significantly to tumor immunity. Herein, six major compounds (carvacrol, thymol, β-phellandrene, α-terpinene, myrcene D, and α-pinene) from Trachyspermum ammi were studied for their intermolecular interactions and stability against PD-1. All tested compounds displayed docking energy (-4.2 to -3.7 kcal/mol) with PD-1. The highest docking scores of -4.2 and -4.1 kcal/mol were recorded for carvacrol and thymol, respectively. Also, a 100 ns molecular dynamics simulation predicted the stability of carvacrol- and thymol-docked PD-1 complex. Maximum of < 30 Å and < 12 Å root-mean-square deviation were observed for carvacrol and thymol at the end of the 100 ns simulation with respect to protein (Cα atoms), indicating retention and displacement of carvacrol and thymol from the initial binding pocket, respectively. Moreover, the endpoint binding free energies support the higher binding affinity of carvacrol (-22.87 ± 5.52 kcal/mol) than thymol (-16.83 ± 1.30 kcal/mol). The equicrural states of the respective ligands were supported by the respective root mean square fluctuation, where no significant deviations in the atoms of the ligands were observed. These findings suggest that carvacrol and thymol inhibit the PD-1/PD-L1 axis.Communicated by Ramaswamy H. Sarma.

Combined in vitro/in silico approaches, molecular dynamics simulations and safety assessment of the multifunctional properties of thymol and carvacrol: A comparative insight

Bioactive compounds derived from medicinal plants have acquired immense attentiveness in drug discovery and development. The present study investigated in vitro and predicted in silico the antibacterial, antifungal, and antiviral properties of thymol and carvacrol, and assessed their safety. The performed microbiological assays against Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica Typhimurium revealed that the minimal inhibitory concentration values ranged from (0.078 to 0.312 mg/mL) and the minimal fungicidal concentration against Candida albicans was 0.625 mg/mL. Molecular docking simulations, stipulated that these compounds could inhibit bacterial replication and transcription functions by targeting DNA and RNA polymerases receptors with docking scores varying between (-5.1 to -6.9 kcal/mol). Studied hydroxylated monoterpenes could hinder C. albicans growth by impeding lanosterol 14α-demethylase enzyme and showed a (ΔG=-6.2 and -6.3 kcal/mol). Computational studies revealed that thymol and carvacrol could target the SARS-Cov-2 spike protein of the Omicron variant RBD domain. Molecular dynamics simulations disclosed that these compounds have a stable dynamic behavior over 100 ns as compared to remdesivir. Chemo-computational toxicity prediction using Protox II webserver indicated that thymol and carvacrol could be safely and effectively used as drug candidates to tackle bacterial, fungal, and viral infections as compared to chemical medication.