Determination of antioxidant activties, phenolic compounds and mineral contents of edible pleurotus eryngii mushrooms

Mushrooms are one of the important food sources consumed for many years all over the world not only for their nutritional values but also they are consumed concerning their medical values. In this study, the extracts of two mushroom types namely Pleurotus eryngii (Eringi) alder and walnut of mushroom obtained by different methodologies were subjected to antioxidant, phenolic compounds and mineral contents analysis. For the methanol and water extracts of mushrooms, total phenolic, total flavonoid, condense tannin content and DPPH activity tests were applied. The phenolic and mineral contents of the methanol extracts were analysed by RP-HPLC-UV and ICP-MS (Inductively Coupled Plasma-Mass Spectrometer) analysis respectively. The results revealed that the total phenolic content of aqueous Eryngii alder mushroom was higher compared to its methanol extract. Similar observation was obtained for the walnut mushroom that revealed the high antioxidant capacity of the water extracts of both mushroom types. Gallic acid, catechin, t-cinnamic acid, myresetin, luteolin and hesperetin were the phenolic compounds detected in both mushroom types by HPLC analysis. Finally, the ICP-MS analysis revealed that although different minerals were found in both mushrooms, the levels of K in both mushrooms were found to be at high levels compared to other minerals.