Abstract
The basidiomycete Agaricus subrufescens Peck, also known as the almond mushroom due to its particular flavor, became in a few years one of the most important culinary-medicinal cultivable mushrooms with potentially high added-value products and extended agronomical valorization. As other mushrooms, it produces metabolites of great interest as potential antioxidant defensive agents to reduce the oxidative damage caused by free radicals. The quality of raw mushrooms or extracts and yield in metabolites may vary with the genetic background of the mushrooms and the environmental conditions. This chapter uses A. subrufescens as a guideline for illustrating the diversity in radical scavenging activities and metabolites in edible fungi, how it can be studied, and how active molecules might be identified.