Antioxidant effects of enzymatic hydrolysates of whey protein concentrate on cultured human endothelial cells

Enzymatic hydrolysis of whey protein concentrate (WPC) was performed using Alcalase, Neutrase, Corolase PP or Flavourzyme. The hydrolysates were filtered through membranes having different molecular mass cut-offs. The hydrolysate fractions had significantly (P < 0.001) greater antioxidant capacity than unhydrolysed WPC, as measured by the oxygen radical absorbance capacity assay (ORAC). Furthermore, incubation of human umbilical vein endothelial cells (HUVECs) with the hydrolysate fractions resulted in an increase in cellular glutathione and catalase activity. Microarray analysis showed beneficial regulation of various genes involved in the antioxidant/detoxification processes in HUVECs incubated with the 5 kDa permeates of WPC hydrolysed by Alcalase or Neutrase. In conclusion, peptides generated by the enzymatic hydrolysis of WPC using Alcalase, Neutrase, Corolase PP or Flavourzyme have a high antioxidant capacity and may have a role in the beneficial regulation of endothelial cell function.