Structural, functional and antioxidant properties of Lentinus edodes protein hydrolysates prepared by five enzymes

The purpose of this study was to investigate structural, functional and antioxidant properties of Lentinus edodes protein hydrolysates (LEPHs) by alcalase, protamex, trypsin, papain and neutrase. Structural and functional properties were determined using gel electrophoresis, Fourier transform infrared spectroscopy, laser scattering, fluorescence spectroscopy, emulsifying properties etc. Antioxidant activities were detected by Fe2+ chelating, hydroxyl and DPPH radical scavenging assays. Enzymatic hydrolysis destroyed secondary and tertiary structures of Lentinus edodes protein, decreased its molecular weight and particle size, particularly hydrolysate prepared by alcalase with the highest hydrolytic degree (32.86 +/- 0.98 %), the smallest particle (130.77 +/- 1.85 nm) and molecular weight (5.86 kDa). Moreover, alcalase hydrolysate exhibited the highest emulsifying stability, the strongest hydroxyl radical scavenging activity and Fe2+ chelating ability among LEPHs. Whilst trypsin hydro-lysate displayed the highest DPPH radical scavenging, foaming and fat absorption capacity. These results pro-vided basis for LEPH as ingredients to be used for food industry.