Production of yeast hydrolysates by Bacillus subtilis derived enzymes and antihypertensive activity in spontaneously hypertensive rats

Numerous studies have been carried out on antihypertensive peptides. However, the separation and purification were too costly, limiting their industrial application. The aim of this study was to produce antihypertensive yeast hydrolyzates (YH) with a simple and cost-saving procedure, coupling fermentation and enzymatic hydrolysis. Crude enzyme, exhibiting protease and beta-glucanase activities, was generated fromBacillus subtilisHu 528 and subsequently used to release and hydrolyze the intracellular proteins from dry yeast. YH exhibited strong ACE inhibitory activity, with IC(50)value of 26.13 mu g/mL, while antihypertensive properties were found on spontaneously hypertensive rats (SHRs) in short- and long-term administrations. YH could increase blood nitric oxide (NO) of SHRs. Moreover, 778 peptides were identified from YH by Nano LC-MS/MS and most of these peptides had ACE inhibitory potentials based on database search and alignment. This study indicated promising potential of YH as a source of ACE inhibitory peptides and potentially could be used in functional foods.