Toxicological Assessment and Dual Protective Roles of Ophiocordyceps sinensis Melanin: Photoprotection and Heavy Metal Detoxification

This research investigated the extraction and purification of melanin from the Ophiocordyceps sinensis TZ8-1; characterized its structural properties; and evaluated its safety, photoprotective efficacy, and ability to mitigate heavy metals. The results demonstrated that the spectral features of TZ8-1 melanin were consistent with those of synthetic melanin, confirming its classification as typical eumelanin. The safety assessment indicated that TZ8-1 melanin has relatively low toxicity to four types of normal human cells, and based on the results of acute oral toxicity tests, this substance showed high safety for experimental animals. Photoprotection studies showed that TZ8-1 melanin effectively suppressed reactive oxygen species (ROS) generation and significantly improved cell viability post-ultraviolet B (UVB) exposure. Heavy metal mitigation experiments showed that TZ8-1 melanin reduced malondialdehyde (MDA) levels, increased glutathione (GSH) concentrations, and enhanced cell survival rates in heavy metal-exposed conditions.