Hydrolysis of Soybean Milk Protein by Papain: Antioxidant, Anti-Angiotensin, Antigenic and Digestibility Perspectives

Abstract

The objective of the investigation was to understand the biochemical activities of hydrolysate of soybean milk protein (SMP). Hydrolysis was carried out by different concentrations of papain (0.008 g·L−1, 0.016 g·L−1, 0.032 g·L−1 and 0.064 g·L−1). The antioxidant capacity was measured by the ferric-reducing ability of plasma (FRAP) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assays. The anti-angiotensin activity of hydrolysate was measured by the recombinant angiotensin converting enzyme and substrate Abz-FRK(Dnp)-P. The contributions of the Kunitz trypsin inhibitor (KTI) and Bowman–Birk inhibitor (BBI) on antigenicity, and the in vitro digestion of papain-hydrolyzed SMP were studied. Rabbit polyclonal anti-KTI and anti-BBI antibodies together with peroxidase-labelled goat anti-Rb IgG secondary antibody were used to identify the antigenicity of KTI and BBI in unhydrolyzed and papain-hydrolyzed SMP. The antioxidant capacity and anti-angiotensin activity of SMP were increased after the papain hydrolysis of SMP. The KTI- and BBI-specific antigenicity were reduced in SMP by increasing the concentration of papain. However, there was interaction between papain-hydrolyzed SMP and trypsin in native gel, while interaction with chymotrypsin was absent. The interaction between trypsin and SMP was reduced due to the hydrolysis of papain in a concentration-dependent manner. According to the in vitro gastrointestinal digestion simulation protocol (Infogest), the digestibility of SMP was not statistically increased.

Proteolysis of β-Lactoglobulin Assisted by High Hydrostatic Pressure Treatment for Development of Polysaccharides-Peptides Based Coatings and Films

“…Furthermore, as the HHP increased from 200 to 600 MPa, the Mw fractions in the 1-5 kDa range changed slightly. Although the content of the various Mw fractions changed with pressure level, no new Mw fractions were produced, which is consistent with previous work [23]. It has been documented that chickpea hydrolysates by papain under 300 MPa exhibited high antioxidant capacity with peptide fractions of <3 kDa having the highest content, and primarily ranging within 500-1000 Da [40].…”

“…Additionally, previous studies reported a higher rising impact of HHP on enzymes under HHP [18]. The peptide profiles in all hydrolysates were expected to be essentially similar to the hydrolysates of native b-LG and b-LG subjected to HHP [23]. In general, HHP treatment of proteins results in high efficiency of proteolysis by various enzymes, which may be attributed to the exposure of cleavage sites of the proteins for the sequential interaction with enzymes [24].…”

Bioactivities of Gaddi Goat Milk Whey Protein Hydrolysates Processed with Papain

“…The process of releasing peptides from casein and whey proteins occurs in three ways: through digestive enzymes, through the fermentation process or through the action of proteolytic enzymes, obtained from microorganisms or plants [25][26][27][28]. The plant enzymes are preferred over enzymes of microbial origin mainly due to safety, lack of pathogenicity and other adverse effects [29,30].…”