From in silico to in vitro: Hydrolysis of cheese whey to obtain peptides with anti-aging and anti-hypertensive activities

Abstract

Our goal was to identify potential anti-aging and anti-hypertensive peptides from the most abundant protein in cheese whey (CW), β-lactoglobulin (BLG), using a multidisciplinary approach. These peptides were generated by three different proteases: trypsin, chymotrypsin and subtilisin. Our bioinformatics approach indicated that trypsin or subtilisin are good candidates for generating anti-hypertensive peptides, whereas chymotrypsin has the highest potential to generate anti-aging fragments, especially anti-elastase. This is mainly due to the presence of chymotryptic peptides with highly similar structures to elastase inhibitors. In addition, we aimed to perform the enzymatic hydrolysis of BLG and evaluate in vitro anti-aging and anti-hypertensive potential by assessing the inhibition to collagenase, elastase and angiotensin-converting enzyme (ACE). We found that chymotrypsin was able to generate a <10 kDa fraction of BLG-hydrolysate that reduces elastase activity (∼15%), which corroborates our interpretation of the in silico data. This fraction also showed reduced ACE activity (∼18%), though statistically similar to the intact protein (∼16%). Peptidomic analysis revealed that peptide sequences with predicted anti-elastase activity were present both in BLG and CW chymotrypsin-hydrolyzed samples, though at higher concentrations in the isolated protein, which may support our experimental results. Lastly, CW was hydrolyzed by chymotrypsin and spray-dried to be used as ingredient in a potentially functional milk-based drink. Hydrolysis significantly impacted the characteristics of the dried powder and the drink containing CW hydrolysate attained better evaluation in sensory analysis. Thus, enzymatic hydrolysis with chymotrypsin generated a potentially functional product that improves bioactivity and functionality of CW.