Unveiling the club moss (Lycopodium clavatum L.): Ethnomedicinal uses, phytochemistry and pharmacological insights

Abstract

Club moss, scientifically known as Lycopodium clavatum L., is a primitive tracheophyte in the family Lycopodiaceae of the pteridophytes. Lycopodium clavatum thrives on exposed, lightly shaded grassland slopes, forest peripheries and disturbed or human-impacted areas such as road cuts. These traits enable them to have widespread distribution in moist forest margins, temperate, subtropical and polar climates. They are documented in Europe, Asia and America. However, according to reports from Plants of the World Online (POWO), the plant is not native to India. The plant is recognised for its considerable ethnomedicinal significance, particularly in homoeopathic remedies across Europe and Asia, where it is used to treat various ailments and contributes to healthcare.  In this review, a comprehensive literature search was performed utilising databases such as Web of Science (WoS), Scopus, PubMed and Google Scholar, employing specific keywords (e.g.,                         "Lycopodium clavatum ethnomedicinal uses," "phytochemicals," "pharmacological activity") up to 2024, concentrating on peer-reviewed English articles and research papers. Ethnomedicinal surveys across more than 10 countries (e.g., Nepal, Bosnia, Canada) document 28 specific uses for 24 ailment categories, including wounds/skin issues (10 reports), respiratory/renal disorders (6 reports), gastrointestinal problems (4 reports), rheumatism/arthritis (3 reports) and others like warts, fever and indigestion. Formulations derived from club moss are predominantly single-plant products (pastes, powders, juices, teas) with rare combinations (e.g., multi-herb teas), mostly from aerial parts/whole plant/spores and no side effects reported in traditional use. Diverse phytoconstituents, including alkaloids, flavonoids and terpenoids, have been reported in the plant. Pharmacological investigations have demonstrated its therapeutic efficacy as an anticancer, antibacterial, anti-inflammatory, hepatoprotective and neuroprotective drug. The plant's potential remains inadequately assessed, with few studies investigating the toxicity of its phytoconstituents. This necessitates further investigation to understand its therapeutic potential and adverse effects. Overall, this review highlights L. clavatum's therapeutic potential and critically evaluates its phytoconstituents, worldwide ethnomedicinal uses and experimentally verified pharmacological properties.