Button mushrooms rival expensive varieties for antioxidants

The button mushroom is the most cultivated edible mushroom in the world, yet it is often considered to be the poor relation to its more exotic and expensive cousins and assumed to be of lesser nutritional value.   Now, however, a French study has found that the white button mushroom (Agaricus bisporus) has as much, and in some cases, more antioxidant properties than more expensive varieties.
Jean-Michel Savoie and colleagues from the Institut National de la Recherche Agrinomique (INRA), a Government research institute in France, tested this assumption on antioxidant capacity by comparing the composition of button mushrooms with those of the maitake (Grifola frondosa) and matsutake (Tricholoma matsutake) mushrooms.  Both the maitake and matsutake mushrooms are highly prized in Japan for their reputed health beneficial properties including lowering blood pressure and their alleged ability to fight cancer.  Antioxidants act as free radical scavengers, 'mopping' such radicals and limiting their ability to cause cell damage, and in doing so provide health benefits by boosting  the body's immune system. 
The French team conducted a number of studies on different parts of the mushrooms, comparing markers of antioxidant activity.  Results showed that the free radical scavenging ability of the white button mushroom was at least equivalent to, if not better than that of the other mushrooms.  They also found that the body of the mushroom had a higher concentration of antioxidants than the stalk. 

Source: Journal of the Science of Food and Agriculture, 2008 doi: 10.1002/jsfa.3175.