A comprehensive review of Drynariae rhizoma: botany, traditional applications, and active flavonoid components.

Objectives: Drynaria fortunei, a species within the Drynaria genus, is a widely distributed medicinal plant with abundant resources. Its rhizome, Drynariae rhizoma, has been extensively utilized in traditional Chinese medicine for its therapeutic efficacy in promoting wound healing, alleviating pain, tonifying the kidneys, and strengthening bones. With a well-documented historical presence in classical texts, Drynariae rhizoma has played a significant role in traditional medical systems across various cultures. Recent phytochemical investigations have identified a diverse array of compounds in Drynariae rhizoma, including flavonoids, phenolic acids, lignans, steroids, and glycosides. Among these, flavonoids represent the principal active constituents, attracting considerable research attention due to their extensive pharmacological activities. This review systematically integrates and critically analyzes the recent research progress in this field,providing a comprehensive overview of the current research landscape,with the aim of identifying promising future directions for Drynariae rhizome.

Methods: This review leveraged a wide range of online databases, including SciFinder, PubMed, SpringerLink, Baidu Scholar, Google Scholar, ScienceDirect, American Chemical Society (ACS) Publications, Web of Science, and China National Knowledge Infrastructure (CNKI), to collect relevant literature. Comprehensive searches were conducted using keywords such as "Drynariae Rhizoma", "flavonoids", "extraction", "chemical constituents", "analytical characterization". To ensure the scientific accuracy of this study, the botanical name of the plant was meticulously cross-verified using authoritative platforms such as "World Flora Online" and "The Plant List."

Key findings: This article provides a comprehensive overview of the botany (including characteristics, distribution, and origin) and traditional applications (such as its historical evolution, botanical sources, and multi-ethnic as well as cross-national therapeutic practices) of Drynariae rhizoma. Additionally, it highlights the latest research advancements on its flavonoid compounds, encompassing extraction methods (e.g. solvent extraction, ultrasound-assisted extraction, and microwave-assisted extraction), analytical characterization (e.g. ultraviolet spectroscopy, high-performance liquid chromatography, and nuclear magnetic resonance), chemical constituents (with 60 flavonoid compounds identified to date), biological activities (e.g. anti-osteoporosis, anti-osteoarthritis, renal protection, dental health promotion, neuroprotection, lipid-lowering, and immunomodulation), and clinical applications. Furthermore, the review discusses current quality control strategies, highlighting the impact of geographical origin and processing methods on flavonoid content. Further in-depth studies are essential to comprehensively explore these areas, paving the way for enhanced understanding and application of Drynariae rhizoma in both traditional and modern medicines.

Conclusions: A comprehensive analysis of existing literature reveals that the flavonoid constituents of Drynariae rhizoma exhibit remarkable therapeutic potential owing to their structural diversity and extensive pharmacological properties. Nevertheless, current understanding of its pharmacodynamic material basis and quality control parameters remains inadequate, highlighting the urgent need for more rigorous investigations to facilitate its broader applications in both traditional and contemporary medical practices. This review is anticipated to provide a rigorous scientific basis for subsequent investigations and clinical translation of therapies based on Drynariae rhizoma.