Characterisation and beneficial effects of a Lupinus angustifolius protein hydrolysate obtained by immobilisation of the enzyme alcalase®.

Bioactive peptides have been considered potential components for the future functional foods and nutraceuticals generation. The enzymatic method of hydrolysis has several advantages compared to those of chemical hydrolysis and fermentation. Despite this fact, the high cost of natural and commercial proteases limits the commercialization of hydrolysates in the food and pharmacological industries. For this reason, more efficient and economically interesting techniques, such as the immobilisation of the enzyme, are gaining attention. In the present study, a new protein hydrolysate from Lupinus angustifolius was generated by enzymatic hydrolysis through the immobilisation of the enzyme alcalase® (imLPH). After the chemical and nutritional characterization of the imLPH, an in vivo study was carried out in order to evaluate the effect of 12 weeks treatment with imLPH on the plasmatic lipid profile and antioxidant status in western-diet-fed apolipoprotein E knockout mice. The immobilisation of alcalase® generated an imLPH with a degree of hydrolysis of 29.71 ± 2.11%. The imLPH was mainly composed of protein (82.50 ± 0.88%) with a high content of glycine/glutamine, arginine, and aspartic acid/asparagine. The imLPH-treatment reduced the amount of abdominal white adipose tissue, total plasma cholesterol, LDL-C, and triglycerides, as well as the cardiovascular risk indexes (CRI) -I, CRI-II, and atherogenic index of plasma. The imLPH-treated mice also showed an increase in the plasma antioxidant capacity. For the first time, this study demonstrates the beneficial in vivo effect of a lupin protein hydrolysate obtained with the alcalase® immobilised and points out this approach as a possible cost-effective solution at the expensive generation of the hydrolysate through the traditional batch conditions with soluble enzymes.

Optimisation and Characterisation of the Protein Hydrolysate of Scallops (Argopecten purpuratus) Visceral By-Products.

In this research, scallops (Argopecten purpuratus) visceral meal (SVM) and defatted meal (SVMD) were analysed for their proximal composition, protein solubility, and amino acid profile. Hydrolysed proteins isolated from the scallop's viscera (SPH) were optimised and characterised using response surface methodology with a Box-Behnken design. The effects of three independent variables were examined: temperature (30-70 °C), time (40-80 min), and enzyme concentration (0.1-0.5 AU/g protein) on the degree of hydrolysis (DH %) as a response variable. The optimised protein hydrolysates were analysed for their proximal composition, yield, DH %, protein solubility, amino acid composition, and molecular profile. This research showed that defatted and isolation protein stages are not necessaries to obtain the hydrolysate protein. The conditions of the optimization process were 57 °C, 62 min and 0.38 AU/g protein. The amino acid composition showed a balanced profile since it conforms to the Food and Agriculture Organisation/World Health Organisation recommendations for healthy nutrition. The predominant amino acids were aspartic acid + asparagine, glutamic acid + Glutamate, Glycine, and Arginine. The protein hydrolysates' yield and DH % were higher than 90% and close to 20%, respectively, with molecular weight between 1-5 kDa. The results indicate that the protein hydrolysates of scallops (Argopecten purpuratus) visceral by product optimised and characterised was suitable a lab-scale. Further research is necessary to study the bioactivity properties with biologic activity of these hydrolysates.