Purification, Structural Characterization and Anti-Aging and Stress Activities of Cordyceps Mycelium Polysaccharides from Paecilomyces Hepiali

This study identified and characterized the bioactive polysaccharide components from Cordyceps mycelium powder (CMP) derived from Paecilomyces hepiali, evaluating their anti-aging and stress-protective activities. Initial screening using Drosophila melanogaster revealed that crude Cordyceps polysaccharides (CCP) exhibited comparable effects to CMP and Cordyceps aqueous extracts (CAE) on natural lifespan and UV stress resistance, suggesting CCP as the primary bioactive component. CCP was purified using ion exchange and size-exclusion chromatography, yielding two homogeneous fractions (CCP-1-1 and CCP-2-1). Structural characterization by HPLC monosaccharide analysis and infrared spectroscopy revealed distinct monosaccharide compositions and functional groups between fractions. In vitro antioxidant assays demonstrated both fractions effectively scavenged hydroxyl radicals (·OH), DPPH radicals, and superoxide anions (O₂⁻), while exhibiting strong reducing power. Using Caenorhabditis elegans as a model organism, both CCP-1-1 and CCP-2-1 significantly extended mean lifespan under normal conditions, heavy metal stress, and UV exposure (p < 0.05). Additionally, CCP-2-1 enhanced survival under heat stress (p < 0.05). Biochemical analysis revealed that both fractions significantly increased antioxidant enzyme activities (superoxide dismutase [SOD] and catalase [CAT]) while reducing malondialdehyde (MDA) levels (p < 0.05), indicating enhanced cellular antioxidant defense. These findings demonstrate that CCP represents the principal anti-aging component of CMP, with purified fractions CCP-1-1 and CCP-2-1 exhibiting potent lifespan-extending and stress-protective effects through modulation of antioxidant enzyme systems. This research provides a foundation for developing Cordyceps-derived polysaccharides as functional ingredients for healthy aging applications.