Production of Antioxidant Peptides from Pea Protein Using Protease from Bacillus licheniformis LBA 46

The objective of this study was to establish the suitable conditions for pea protein hydrolysis using the response surface methodology (RSM). The antioxidant hydrolysates produced by proteases from Bacillus licheniformis LBA 46 and commercial Alcalase 2.4L were compared. The hydrolysis conditions, pH value (10) and enzyme concentration (100 U/mL) were selected as the main processing conditions for the hydrolysis. The experimental values for 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, oxygen radical absorbance capacity (ORAC), and ferric reducing antioxidant power (FRAP) under the chosen conditions were 3.64, 568.7 and 9.18 Trolox equivalent/g of protein hydrolysates (TE mu mol/g) for LBA protease hydrolysates and 3.77, 719.67 and 9.17 TE mu mol/g for Alcalase 2.4L hydrolysates, respectively. Compared to the non-hydrolyzed pea protein, the antioxidant activity measured in terms of DPPH and FRAP was reduced, however, the antioxidant activity measured by ORAC assay, was improved. The LBA protease showed similar action to Alcalase 2.4L, demonstrating its potential use.