Extraction, structural-activity relationships, bioactivities, and application prospects of pine pollen polysaccharides as ingredients for functional products: A review

Pine pollen, a nutrient-rich pollen, is composed of significant amounts of protein, vitamins, and carbohydrates, featuring various functional groups. Pine pollen polysaccharide (PPP), a key bioactive component of pine pollen, exhibits a range of pharmacological activities, including anti-tumor, liver-protective, lipid-lowering, anti-inflammatory, immunomodulatory, antioxidant, hypoglycemic, antiviral, and antibacterial properties. While numerous extraction and purification techniques have successfully isolated and characterized PPPs, understanding of their structure-activity relationships, safety profiles, and practical applications remains limited. This hampers their full potential in utilization and development. In this article, we present a comprehensive overview of the extraction, purification, structure characteristics, structural-activity relationships, biological activities, and pharmaceutical applications of PPPs derived from various sources, including Pinus massoniana Lamb, Pinus tabuliformis Carr, and related species. This review aims to provide extensive knowledge and insights for future research and the application of PPPs as therapeutic agents and versatile biomaterials.