Phytochemical Characterization, Taxonomic Insights, and Immunomodulatory Mechanisms of Echinacea purpurea: A Comprehensive Review on Its Role in Enhancing Host Defences Against Viral and Bacterial Pathogens

Background: Echinacea purpurea (L.) Moench, commonly known as purple coneflower, has been traditionally employed in North American and European herbal medicine for its immune-enhancing properties. In the context of increasing antimicrobial resistance and recurrent viral outbreaks, interest in botanicals with immunomodulatory potential has grown substantially. Objective: To provide a comprehensive synthesis of the phytochemical profile, taxonomic attributes, immunomodulatory mechanisms, and antimicrobial activities of E. purpurea, while identifying research gaps and future directions. Methods: A narrative review was conducted using peer-reviewed literature from databases such as PubMed, Scopus, and Web of Science, focusing on studies published between 1980 and 2025. Key inclusion criteria encompassed original research and reviews reporting on phytochemistry,