Production of enzymatic hydrolysates with in vitro antioxidant, antihypertensive, and antidiabetic properties from proteins derived from Arthrospira platensis

The microalga Arthrospira platensis BEA 005B was produced using 80 m2 (9 m3) raceway photobioreactors achieving a biomass productivity of 28.2 g·m−2·day−1 when operating the reactors in semi-continuous mode (0.33 day−1). The produced biomass was rich in proteins (58.1 g·100 g−1) and carbohydrates (25.6 g·100 g−1); the content of phycocyanins and allophycocyanins was 115.4 and 36.9 mg·g−1, respectively. Ultrasounds and high-pressure homogenisation allowed recovering approximately 90% of the initial protein content of the biomass; however, the energetic requirements of the former (∼100 kJ·kg−1) were significantly lower than those of high-pressure homogenisation (∼200 kJ·kg−1). An in silico analysis revealed that papain and ficin would allow releasing a large number of bioactive peptides with antioxidant, antihypertensive (ACE-I and renin), and antidiabetic (DPP-IV, α-amylase, and α-glucosidase) properties. Both were assessed in vitro together with Alcalase and pepsin leading to the generation of enzymatic hydrolysates with in vitro bioactivity.