Comparative study of biological activities and chemical constitution of Agaricus subrufescens and Pleurotus ostreatus mushrooms

There are approximately 2,000 species of edible mushrooms found in the world, of which only 25 are cultivated on a large scale for commercial purposes. Among these, the main species cultivated in Brazil are: Pleurotus ostratus (shimeji), and, recently, Agaricus subrufescens (mushroom of the sun) [1], [2]. Thus, the aim of this study is to evaluate the antioxidant activity, the total phenolic content, and to identify the bioactive compounds of A. subrufescens and P. ostreatus by LC-MS/MS. The antioxidant activity of hydroalcoholic extract was evaluated by 1,1-diphenyl-2-picryhydrazyl radical (DPPH^•) method and oxygen radical absorbance capacity (ORAC) assay, while the phenolic content was quantified by Folin-Ciocalteu method. The A. subrufescens extract presented higher antioxidant activity (54.71 ± 3.45 g of the Gallic acid equivalent (GAE) 100 g⁻¹) than the P. ostreatus extract (28.99 ± 0.63 g GAE 100 g⁻¹). The same results were obtained by ORAC method: A. subrufescens presented higher antioxidant activity (5.95 ± 0.092 g GAE 100 g⁻¹) than P. ostreatus (0.76 ± 0.029 g GAE 100 g⁻¹). The A. subrufescens also presented higher values of phenolic content 92.94 ± 0.30 mg GAE 100 g⁻¹ compared to P. ostratus (16.48 ± 0.65 mg GAE 100 g⁻¹). Three compounds were identified by LC-MS/MS in both species based on the fragmentation pattern reported in the literature [3]: p-coumaric acid, caffeoyl hexose, and saccharopine, among which the first two presents antioxidant metabolites reported in the literature. Therefore, the higher phenolic content observed for A. subrufescens can explain its potent antioxidant effect.

• References

• 1 Endo M. et al. Agaritine purified from Agaricus blazei Murrill exerts anti-tumor activity against leukemic cells. Biochim Biophys Acta 2010; 180: 669-673
• 2 Sánchez C. Cultivation of Pleurotus ostreatus and other edible mushrooms. Appl Microbiol Biotechnol 2010; 85: 1321-1337
• 3 Fraige K. et al. Dereplication by HPLC-DAD-ESI-MS/MS and screening for biological activities of Byrsonima species (Malpighiaceae). Phytochem Anal 2018; 29: 196-204