Wine cap mushroom (Stropharia rugosoannulata) is rich in protein and peptides, with dried mushrooms containing up to 50% protein and 15% free peptides. Using four ultrasound frequencies helped extract more of these compounds, reaching 60% protein and 34% peptides, and the resulting mixture showed blood-pressure-related activity comparable to captopril in testing. Better extraction could turn edible mushrooms into more potent heart-health ingredients.