Mushrooms are highest dietary source of two antioxidants ergothioneine and glutathione with glutathione referred to as the "mother of all antioxidants." *Porcini mushrooms have the highest concentration. #health #nutrients Tips on Serving Portobello Mushrooms to Pets Before offering your pet portobello mushrooms, wash them under cold running water and gently cook them. Research suggests the nutritional properties of mushrooms are Glutathione Short term regulation of the hepatic activities of cytochrome P450 and glutathione S transferase by nose only cigarette smoke exposure in mice ScienceDirect