ERGO+ L Ergothioneine Marcus Institute of Integrative Health Ergothioneine: The Elusive Amino Acid reishi and roses Magnificent Mushrooms American Society for Nutrition In a study, researchers found that mushrooms have high amounts of the ergothioneine and glutathione, both important antioxidants, said the senior author. The researchers also found that the amounts the two compounds Frontiers Mushrooms as Potential Sources of Active Metabolites and Medicines