Thymus vulgaris for COVID-19

The COVID-19 pandemic has renewed global interest in medicinal plants as accessible sources of prophylactic and supportive therapies. Ethnobotanical research provides an important foundation for developing plant-based medicines with preventive and therapeutic potential. This study aimed (1) to investigate the distribution and indications for the use of medicinal plants in the prevention and relief of COVID-19-related symptoms among the Bulgarian population, and (2) to identify culturally significant species with potential for further development as antiviral agents. A total of 513 respondents from different regions and demographic groups in Bulgaria were interviewed. Their knowledge regarding the use of medicinal plants for COVID-19 prevention or treatment was quantitatively assessed using ethnobotanical indices: relative frequency of citation (RFC), informant consensus factor (FIC), fidelity level (FL), and use value (UV). Participants reported 45 species belonging to 43 genera and 23 families. The highest RFC and UVs were recorded for Matricaria chamomilla L., Tilia sp., Thymus vulgaris L., Zingiber officinale Roscoe, Mentha sp., Citrus x limon (L.) Osbeck, Rosa canina L., and Sideritis scardica Griseb. Culturally significant species identified were Thymus vulgaris L., Matricaria chamomilla L., Tilia sp., Mentha sp., Sideritis scardica Griseb, Zingiber officinale Roscoe, and Citrus x limon (L.) Osbeck. This ethnobotanical survey in Bulgaria documents culturally important medicinal plants that may have potential applications in prophylaxis and complementary therapy for COVID-19.

AbstractCoronaviruses (CoVs) are a family of viruses that cause infection in respiratory and intestinal systems. Different types of CoVs, those responsible for the SARS‐CoV and the new global pandemic of coronavirus disease 2019 in people, have been found. Some plants were used as food additives: spices and dietary and/or medicinal purposes in folk medicine. We aimed to provide evidence about possible effects of two Lamiaceae family plants on control or treatment of CoVs‐induced inflammation. The keywords including coronaviruses, Thymus vulgaris, Zataria multiflora, thymol, carvacrol, antivirus, and anti‐inflammatory and antioxidant effects were searched in various databases such as PubMed, Web of Sciences (ISI), and Google Scholar until September 2022. The medicinal herbs and their main ingredients, thymol and carvacrol, showed antiviral properties and reduced inflammatory mediators, including IL‐1β; IL‐6, and TNF‐α, at both gene and protein levels but increased the levels of IFN‐γ in the serum as anti‐inflammatory cytokine. These medicinal herbs and their constituents also reduce oxidative stress and enhance antioxidant capacity. The results of molecular docking analyses also indicated that polyphenol components such as thymol, carvone, and carvacrol could inhibit the entry of the viruses into the host cells in molecular docking analyses. The antiviral, anti‐inflammatory, and antioxidant effects of these plants may be due to actions of their phenolic compounds that modulate immune response and may be useful in the control and treatment of CoV‐induced lung disorder.