Screening of bioactive peptides from winemaking industry by-products: protein hydrolysis optimization and antihypertensive effects (Confererencia invitada)

FONTANA, ARIEL; KNUF, FRANZISKA; SCHIEBER, ANDREAS

Valencia

Conferencia; 37th EFFoST International Conference 2023; 2023

European Federation of Food Science and Technology (EFFoST)

Aim: Food-derived bioactive peptides are specific protein fragments normally containing short sequences between 3-20 amino acid units. They can be considered as components of functional foods which may exert regulatory activities in the human organism, irrespective of their nutritive functions and potential antioxidant activities. These peptides encrypted within the sequence of the parent proteins can be released by enzymatic hydrolysis. Due to the varying specificity of the enzymes, hydrolysis with different enzymes or combinations of them may produce diverse peptides originating from the same protein.Therefore, also the bioactivity of the hydrolysates may differ.Method: In this work, the release of peptides from grape pomace (GP) and wine lees (WL) proteins by Alcalase (A), Flavourzyme (F) and Protease (P) and their combinations was investigated. Degree of hydrolysis (DH) was used to evaluate the efficiency of the enzymes during the optimization studies. Under optimum conditions, peptides were separated in twofractions (smaller and higher than 3 KDa) by ultrafiltration and their bioactivity was evaluated using an angiotensin I converting enzyme inhibitory (ACEi) activity assay. Subsequently, this fraction was purified by preparative chromatography and the qualitative peptide patterns of GP and WL protein hydrolysates of more active fractions were determined by UHPLCMS/MS with an Orbitrap Fusion Lumos system.Results: After optimization of digestion conditions, DH ranging between 13 and 46 % and between 25 and 86 % for GP and WL, respectively, were obtained. The combination of enzymes (A+P) allowed an increase in the DH in an average of 13 and 40 % for GP and WL. Besides the increased DH using the enzyme combinations, the ACE inhibitory activities were similar or lower than by applying the individual enzymes. In general, the fraction 3 kDa and peptide solution that was not fractionated, with F and A yielding the highest activities for GP and WL, respectively. The 50 % inhibitory concentration values (IC50) were 52 μg/mL for F in GP and 21 μg/mL for A in WL.Conclusion: GP and WL protein hydrolysates may be a source of bioactive peptides with potential to be used as a health promoting ingredient with ACE inhibitory activities.