Spirulina platensis protein hydrolysates: Techno-functional, nutritional and antioxidant properties

In this study, pancreatin and pepsin (as gastrointestinal proteases) were used to obtain bioactive peptides from Spirulina platensis protein and the techno-functional and antioxidant characteristics of the produced peptides were evaluated. There was only a weak band in the molecular weight (Mw) range less than 10 KDa for the electrophoretogram of both hydrolyzed peptides. Pepsin hydrolysates (H-Pep) exhibited a higher degree of hydrolysis (16%) and antioxidant activity (IC50: 0.5 mg.mL) than pancreatin hydrolysates (H-Pan) (11% degree of hydrolysis and IC50:1.5 mg.mL). H-Pep and H-Pan significantly reduced lipid oxidation in emulsions (48% and 17%, respectively) as compared to native protein. Digested H-Pep hydrolysates retained their antioxidant activity, whose values were similar to the non-digested samples. The biocompatibility of the produced hydrolysates was indicated by the MTT test (as a colorimetric assay to assess cell viability). The amino acid profile results showed that H-Pep from Spirulina algae might be served as an interesting protein source for food products with good nutritional value as determined by quality index (1.1), amino acid score (67%), biological value (70%), and also good antioxidant and emulsifying activity.