Multifunctional in vitro bioactive properties: Antioxidant, antidiabetic, and antihypertensive of protein hydrolyzates from tarwi (Lupinus mutabilis Sweet) obtained by enzymatic biotransformation

Background and objectives: Tarwi is a legume that grows in the Andean region of Peru. This grain is characterized by having a high protein content (~42%). In order to generate added-value products from this resource, the possibility of obtaining tarwi protein hydrolyzates (TPH) with in vitro bioactive properties was evaluated using Alcalase, Neutrase, and Flavourzyme enzymes, acting alone or in combination for up to 240 min. The in vitro evaluated properties were as follows: antioxidant (ABTS assay), antidiabetic (α-amylase, α-glucosidase and dipeptidyl peptidase IV (DPP-IV) inhibition), and antihypertensive (angiotensin-converting enzyme-I (ACE) inhibition). Findings: The TPH obtained from the different enzyme treatments exhibited important antioxidant, antidiabetic (specially for DPP-IV inhibition), and antihypertensive properties. One-stage treatment using Alcalase for 240 min and two sequential stage treatments with Alcalase–Neutrase for 180 min presented the highest ABTS antioxidant activity and lowest IC₅₀ values for DPP-IV and ACE corresponding to 2.0–1.95 µmol TE/mg, 2.14–2.61 and 0.16–0.11 mg/ml, respectively. Conclusions: The results of this research demonstrate that TPH exhibit in vitro multifunctional bioactive properties. Significance and novelty: TPH could potentially be used in the prevention or management of chronic diseases related to the development of oxidative processes, diabetes, and hypertension.