Preparation and Antioxidant Activities of Peanut (Arachin conarachin L.) Protein Peptides by Bacillus Subtilis Solid State Fermentation Method

The objective of this work is to study on preparation of peanut protein peptide by bacillus subtilis solid state fermentation method. Results indicated that soluble nitrogen concentration of protein peptide could reach 122.86mg/mL, 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) and hydroxyl free radicals scavenging rates were 85.22% and 84.88%, respectively, under the following optimum conditions: nutrient salt solution of 16.3mL, bacterial suspension volume of 3.8mL, temperature of 45°C, and time of 41h. IC50values for scavenging of DPPH, hydroxyl and superoxide anion free radicals rates, iron and copper ion chelating rates, inhibition rate of anti-lipid peroxidation were 2.88mg/mL, 4.63mg/mL, 1.22mg/mL, 0.04mg/mL, 0.94mg/mL, 3.78mg/mL, respectively. When absorbance value of iron and molybdenum reduction capacities was 0.5, the required protein peptide concentrations were 7.28mg/mL and 1.85mg/mL, respectively.