Antioxidant activity of arrowhead protein hydrolysates produced by a novel multi-frequency S-type ultrasound-assisted enzymolysis.

Effects of multi-frequency S-type ultrasound (MFSU) assisted arrowhead protein (AP) hydrolysis on the antioxidant activity of its hydrolysates were studied. The results showed the DPPH• and ABTS•+ scavenging activity of hydrolysates obtained with dual frequency ultrasound (20/40 kHz) was 63.61% and 65.11%, respectively, and was higher than that noted for hydrolysates acquired with assistance of other mode (single and triple frequency ultrasound). Compared with hydrolysates without ultrasonic treatment, products of AP hydrolysis assisted by dual frequency ultrasound (20/40 kHz) could significantly alleviate oxidative stress induced by H2O2 in RAW 264.7 cells, mainly embodied in improving the survival rate and increasing the activity of antioxidant enzymes (CAT and SOD). Taken together, these results showed that MFSU-assisted enzymatic treatment can significantly improve the antioxidant activity of AP hydrolysates. Thus, the development of the novel MFSU could lay a foundation for assisting the protein enzymolysis in food and pharmaceutical industries.