Effect of selenium on mushroom growth and metabolism: A review

Background Selenium-enriched mushrooms represent an important daily source of selenium in food products. Selenium is an essential micronutrient that enhances various biological activities, including the antioxidant, antitumor, and immune-regulatory properties of mushrooms. Scope and approach From the perspective of how selenium influences the growth and metabolism of mushrooms during the process of selenium biofortification, this review summarizes recent literature regarding mushroom growth phenotypes, major selenium metabolites, particularly selenium-polysaccharide, selenium-protein, and selenoamino acid, as well as other bioactive metabolites. In addition, a proposed selenium metabolic pathway is presented in well-studied mushrooms, thus providing a basis for further research on selenium metabolism. Key findings and conclusions Selenium-enriched mushroom cultivation primarily uses sodium selenite as the selenium source. However, although adding selenium at low concentrations promotes mushroom growth, high concentrations have the opposite effect. Nevertheless, selenium enrichment cultivation is a valid strategy for improving bioactivity as mushrooms can transform inorganic selenium into numerous important organic selenium metabolites, particularly selenium-polysaccharides, selenium-proteins and selenoamino acids. In addition, phenolics and flavonoids, basic amino acids, cordycepin, and adenosine are enhanced in mushrooms supplied a moderate level of selenium. This characterization of the unique aspects of the proposed selenium metabolism pathway in Ganoderma lucidum advances provides insights regarding selenium metabolism in mushrooms. Consequently, understanding the effect of selenium on mushroom growth and metabolism will improve the production of mushrooms with high bioactive Se metabolite content and good bioactivity, while contributing to the development and application of selenium-enriched mushrooms in the food industry.