Evaluation of subchronic oral dose toxicity of Antrodia camphorata mycelium powder in rodents as a novel food source

Antrodia camphorata ( A. camphorata ), also known as “Niuchangchih” in Taiwan, is a medicinal fungus traditionally used for its hepatoprotective, anti-inflammatory, and anticancer properties. However, the safety and potential toxic effects of its mycelium form have not yet been fully established. This study aimed to evaluate the subchronic oral toxicity and determine the no observed adverse effect level (NOAEL) of A. camphorata mycelium powder in Sprague Dawley (SD) rats under Good Laboratory Practice (GLP)-compliant conditions. SD rats (10/sex/group) were administered A. camphorata mycelium powder orally at doses of 0, 500, 1000, and 2000 mg/kg/day as a 10 ml/kg/day suspension in water for 13 weeks. A 4-week recovery study was conducted at 0 and 2000 mg/kg/day with 5 rats/sex/group. Dose-dependent increases in liver and adrenal weights were noted, accompanied by hepatocellular and adrenal cortical hypertrophy, which were fully reversed in males and showed a tendency toward recovery in females after the recovery period. Repeated oral administration of A. camphorata mycelium powder for 13 weeks produced no adverse systemic toxicity in rats. The NOAEL was determined to be 2000 mg/kg/day in both sexes, supporting its safety for further development as a functional food or medicinal product. These findings provide important safety data supporting its further application in health supplements.