Immune-Boosting Plants Used in Turkish Folk Medicine and their Potential against COVID-19

Having suffered from a global epidemic of Covid19 mutants and variants, the entire world has turned its attention and hope to natural treatments that can keep the immune system active and strong. Recent research on some herbal preparations promises high hopes that they may be potential candidates for developing effective and safe immune-boosting drugs. Considering that Turkey has the richest flora of Europe and the Middle East and has an invaluable ethnomedical background, it offers a treasure-worthy potential for serious researchers. 128 plant taxa belonging to 41 families were determined from 99 works carried out in different regions of Turkey. Of these, only 60 (46.9%) were found to be responded to in experimental studies worldwide on immune system enhancement and other similar activities. Quercetin (10.3%), β-glucan, and catechin (5.1%) emerged as the most common active substances among 39 identified active substances. Urtica dioica (39.4%), Rosa canina (34.3%), and Punica granatum (17.2%) were recorded as the most used plants in Turkey. In addition, Phoenix dactylifera has appeared as the taxon with having more active compounds in the literature. This study presents the first national inventory of immune-boosting plants that are regularly used in traditional Turkish medicine, not only against Covid-19 but for the prevention and treatment of epidemic diseases in general. We present 68 (53.1%) plants whose effective immune-stimulating and strengthening properties have been confirmed in experimental studies in the world literature as ready-made material to the relevant pharmacological sectors.