A polysaccharides-based delivery system was designed to encapsulate and control the release of peanut peptide (PP). The PP-loaded polyelectrolyte complex (TMC-PP-SA) was fabricated based on the electrostatic self-assembly between n-trimethy chitosan (TMC) and sodium alginate (SA). The complex exhibited uniform spherical morphology, satisfactory stability and high encapsulation efficiency. In vitro release behavior indicated that TMC-PP-SA polyelectrolyte complex could inhibit the release of PP at simulated gastric medium and enhance the release of PP at simulated intestinal medium. Moreover, the antioxidant activity of PP after encapsulation was significantly improved compared with that of directly digested PP. Ex vivo intestinal permeation study confirmed that about 41.76 ± 1.43% PP in TMC-PP-SA could be absorbed in the intestinal. The cytotoxicity measurement indicated that the fabricated TMC-PP-SA polyelectrolyte complex was biocompatible and nontoxic. Therefore, these results indicated that the polysaccharides-based delivery system had great potential in protecting active peptides from degradation and facilitating their absorption.
The browning formation and taste enhancement of peptides derived from soybean, peanut, and corn were studied in the light-colored Maillard reaction compared with the deep-colored reaction. The fluorescent compounds, as the browning precursors, were accumulated during the early Maillard reaction of peptides and subsequently degraded into dark substances, which resulted in a higher browning degree of deep-colored Maillard peptides (MPs), especially for the MPs derived from corn peptide. However, the addition of l-cysteine in light-colored Maillard reaction reduced the formation of deoxyosones and short-chain reactive α-dicarbonyls, thereby weakening the generation of fluorescent compounds and inhibited the browning of MPs. Synchronously, the peptides were thermally degraded into small peptides and amino acids, which were consumed less during light-colored thermal reaction due to its shorter reaction time at high temperature compared with deep-colored ones, thus contributing to a stronger saltiness perception of light-colored MPs than deep-colored MPs. Besides, the Maillard reaction products derived from soybean and peanut peptides possessed an obvious “kokumi” taste, making them suitable for enhancing the soup flavors.
Marine bacterial proteases have rarely been used to produce bioactive peptides, although many have been reported. This study aims to evaluate the potential of the marine bacterial metalloprotease A69 from recombinantBacillus subtilisin the preparation of peanut peptides (PPs) with antioxidant activity and angiotensin-converting enzyme (ACE)-inhibitory activity. Based on the optimization of the hydrolysis parameters of protease A69, a process for PPs preparation was set up in which the peanut protein was hydrolyzed by A69 at 3000 U g−1and 60 °C, pH 7.0 for 4 h. The prepared PPs exhibited a high content of peptides with molecular weights lower than 1000 Da (>80%) and 3000 Da (>95%) and contained 17 kinds of amino acids. Moreover, the PPs displayed elevated scavenging of hydroxyl radical and 1,1-diphenyl-2-picryl-hydrazyl radical, with IC50values of 1.50 mg mL−1and 1.66 mg mL−1, respectively, indicating the good antioxidant activity of the PPs. The PPs also showed remarkable ACE-inhibitory activity, with an IC50value of 0.71 mg mL−1. By liquid chromatography mass spectrometry analysis, the sequences of 19 ACE inhibitory peptides and 15 antioxidant peptides were identified from the PPs. These results indicate that the prepared PPs have a good nutritional value, as well as good antioxidant and antihypertensive effects, and that the marine bacterial metalloprotease A69 has promising potential in relation to the preparation of bioactive peptides from peanut protein.
危险品化学品经营许可证（带存储）