Mineral composition of different strains of edible medicinal mushroom Agaricus subrufescens Peck

Agaricus subrufescens Peck is a well-known Basidiomycota fungus (Royal Sun Agaricus), with rising demand in consumption and production worldwide. This particular mushroom with high medical value has been used successfully in cancer therapy and in the treatment of some bacterial and viral diseases. Four strains of A. subrufescens (Si2.2, 853, 1105, and 2603) were cultivated, and 22 mineral elements of basidiomes (fruit bodies) were analyzed (caps and stipes separately). The data obtained about the mineral compositions were compared to the "reference" Agaricus bisporus (white button mushroom) and to the average of wild growing Agaricus species. The mineral composition of A. subrufescens strains can be characterized by the following: (1) high levels of valuable macroelements, i.e., potassium (28-30,000 mg/kg of dry matter), phosphorus (7-11,000 mg/kg of dry matter), and calcium and magnesium (for both elements, 1,000-1,500 mg/kg of dry matter); (2) significantly higher level of copper (compared to A. bisporus, 70-150 mg/kg of dry matter) and zinc (140-250 mg/kg of dry matter); (3) low quantity of sodium (140-180 mg/kg of dry matter); (4) attention should paid to the detectable amount of cadmium (2-17 mg/kg of dry matter) in strain Si2.2; (5) low or undetectable concentrations of some other poisonous microelements like As, Cr, and V; and (6) the distribution of elements in caps and stipes is characteristic-the majority of beneficial elements have higher contents in caps than in stipes, but some other elements, such as Ca, Fe, and Na, appear in an inverse proportion. In conclusion, it can be said that the mineral composition of A. subrufescens is definitely positive, with the exception of the above-mentioned Cd level.