Hypsizygus marmoreus (Bunashimeji), a popular edible mushroom in East Asia, is recognized for its therapeutic properties, including antioxidant activity. Ultraviolet (UV) radiation, particularly UVB, induces reactive oxygen species (ROS), accelerating skin aging and elevating cancer risk. This study evaluated the antioxidant and anti-photoaging potential of aqueous crude extracts of H. marmoreus prepared by cold water extraction (CWE) and hot water extraction (HWE). Antioxidant capacity was assessed through total phenolic content (TPC), total flavonoid content (TFC), reducing power, ferrous ion chelating activity, and DPPH radical scavenging assays, while cytotoxicity and protective effects were examined in fibroblast cells using MTT. CWE contained significantly higher phenolic content than HWE (p < 0.001), indicating stronger antioxidant potential. No significant differences were observed in TFC and chelating activity (p > 0.05). CWE demonstrated greater reducing power at 5–15 mg/mL (p < 0.05), while both extracts exhibited concentration dependent DPPH scavenging activity, with CWE showing slightly higher efficacy. Neither extract surpassed the standard in ferrous ion chelation. MTT analysis confirmed non-cytotoxicity of both extracts and revealed enhanced fibroblast viability, suggesting a protective effect against oxidative stress. In conclusion, CWE of H. marmoreus exhibited superior antioxidant properties compared to HWE, particularly in phenolic content and reducing power, and supported fibroblast survival. These findings suggest that H. marmoreus holds promise as a natural photoprotective agent for anti-aging and skin-care formulations.

Hypsizygus marmoreus, Antioxidant, Anti Photo-aging, Crude Extract