Production of black cricket protein hydrolysates with α-amylase, α-glucosidase and angiotensin I-converting enzyme inhibitory activities using a mixture of proteases

Abstract

The objective of this work was to evaluate the in vitro antidiabetic and antihypertensive properties of protein hydrolysates obtained by enzymatic hydrolysis of black cricket (Gryllus assimilis) protein concentrate. The enzymatic hydrolysis was carried out by isolated application and in binary/ternary combinations of the commercial enzymes Flavourzyme™ 500 L, Alcalase™ 2.4 L and Neutrase™ 0.8 L, using an experimental mixture design. The in vitro antidiabetic properties of the protein hydrolysates were assessed through the ability to inhibit α-amylase and α-glucosidase activities, while the inhibition of the angiotensin-converting enzyme (ACE) was used to measure the potential antihypertensive property. The results showed that most of the samples had their inhibitory activities increased after enzymatic hydrolysis when compared with the non-hydrolyzed sample. The highest percentual of inhibition of α-amylase and α-glucosidase activities was 55.40% and 17.07%, respectively, detected for the protein hydrolysate produced with the binary mixture of Flavourzyme™ 500 L and Neutrase™ 0.8 L. The highest ACE inhibitory activity was 50.84%, detected for the sample produced by the use of a binary combination of Flavourzyme™ 500 L and Alcalase™ 2.4 L. Fractionation by ultrafiltration confirmed that small peptides resulted in improved bioactive properties. Antidiabetic and antihypertensive peptides such as AGDDAPR and YPLDL were identified, in addition to sequences homologous to those already described as bioactive in the BIOPEP database. The enzymatic hydrolysis proved to be a process capable of significantly increasing the in vitro antidiabetic and antihypertensive properties of black cricket protein.