Extraction and Plastein Reaction of Bioactive Peptides from Agaricus Bisporus Mushrooms ^†

The common mushroom Agaricus bisporus has a high content of proteins and other bioactive compounds, which gives its high medicinal value [1]. The aim of this study was to generate enzymatic protein hydrolysate from Agaricus bisporus mushrooms, useful as bioactive peptides in different applications, such as obtaining plant biostimulant products or new generations of synbiotic formulations with prebiotics and probiotic microorganisms. In the past decades, attention has been drawn to the plastein reaction, which is a way for increasing nutritional value of proteins, but also for removing the bitterness of protein hydrolysates [2]. The mushrooms were lyophilized, and the powder was used for the extraction of proteins with enzymes, different buffer solutions, and different commercial, natural, deep eutectic solvents (NADESs) in order to optimize the extraction of proteins from Agaricus bisporus and to quantify the total amount of proteins extracted using the dye binding assay method (Bradford) or copper-based assays (Biuret, Lowry, BCA) against a bovine serum albumin (BSA) standard curve [3]. The molecular weights of the proteins were analyzed on sodium dodecyl sulfate (SDS) - Polyacrylamide Gel Electrophoresis (SDS-PAGE). The enzymatic hydrolysis of proteins was performed using a protease from Bacillus licheniformis, and the plastein was synthetized using the same enzyme to avoid extra proteolysis in the course of plastein reaction so as to increase plastein yield. Tangential ultrafiltration was used for purification and concentration of peptide samples. Synthetized plastein was analyzed using Dynamic Light Scattering (DLS) and SDS-PAGE.