Antioxidant and antimicrobial activities of different enzymatic hydrolysates from desalted duck egg white

Abstract

Objective: The objective of this study was to look for optimal preparation of hydrolysates of desalted duck egg white powder (DDEWP) by the three different proteases and to investi gate their antioxidant and antimicrobial properties. Methods: DDEWP was hydrolyzed by three proteases, including pepsin (PEP), Bacillus spp. (BA) and natokinase (NAT) with three different enzyme concentrations (0.1%, 0.3%, and 0.5%), individually. The important key hydrolysis parameters such as hydrolysis degree, yield, antioxidant and antimicrobial activity were evaluated in this experiment. Results: The results showed that the degree of hydrolysis (DH) of all treatments increased with increasing hydrolysis time and protease concentrations. The antioxidant and antimicro bial activities of the hydrolysates were affected by type and concentration of protease as well as hydrolysis time. Hydrolysis of PEP significantly (p<0.05) obtained the highest yield of hydrolysates, however, both of BA and NAT showed substantially lower DH values and still did not exceed 5% by the end of hydrolysis. Among the different hydrolysates, PEP ex hibited significantly higher 2, 2-diphenyl1picrylhydrazyl (DPPH) radical scavenging activity than BA and NAT. All DDEWP hydrolysates from PEP had low ferrous ion chelating activity (<37%) that was significantly lower than that of NAT (>37% to 92%) and BA (30% to 79%). Besides, DDEWP hydrolysates of PEP presented significantly higher reducing power than BA and NAT. In antimicrobial activities, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa were not effectively inhibited by any DDEWP hydrolysates of PEP except for Staphylococcus aureus. Especially, the excellent antibacterial activity against S. aureus only was displayed in DDEWP hydrolysates of PEP 0.1%. Conclusion: DDEWP hydrolysates from PEP demonstrated significantly better DH, yield, DPPH radical scavenging activity and reducing power, furthermore, had excellent inhibitory on S. aureus due to large clear zone and moderated inhibitory in bactericidal inhibition.

Porcine placenta hydrolysate as an alternate functional food ingredient: In vitro antioxidant and antibacterial assessments

“…The results showed that the DH had a strong influence on the antioxidant activities of PPH. Thammasena and Liu [ 56 ] discovered that the DH correlated positively with the antioxidant capacity of desalted duck egg white hydrolysate.…”

Mooncake production waste: Nutritional value and comprehensive utilization of salted duck egg white

“…The principle of desalination by electrodialysis is that under the action of a direct current electric field, the ion exchange membrane selectively removes salts by anions and cations. The desalination efficiency of electrodialysis has reached more than 95%, but the energy consumption is relatively large, and the protein is easily denatured (Thamamsena, & Liu, 2019).…”

“…The principle of desalination by electrodialysis is that under the action of a direct current electric field, the ion exchange membrane selectively removes salts by anions and cations. The desalination efficiency of electrodialysis has reached more than 95%, but the energy consumption is relatively large, and the protein is easily denatured (Thamamsena, & Liu, 2019). The method of ion exchange resin is to use H‐type cation exchange resin to exchange various cations in water into H + , and use OH‐type anion exchange resin to exchange various anions in water into OH − , thereby removing or reducing salts in water.…”

VF‐4 and DR‐8 Derived from Salted Egg White Inhibit Inflammatory Activity via NF‐κB/PI3K‐Akt/MAPK Signal Transduction Pathways in HT‐29 Cells Induced by TNF‐α

“…This not only causes the waste of high-quality protein resources in the salted egg white, but also causes pollution to the environment and water sources due to the fermentation and decomposition products of the salted egg white exposed to the air. [11,12] Salted egg white is rich in protein and has similar nutritional value and ingredients to eggs. As we all know, egg white has a variety of biological activities, including antioxidant, anti-inflammatory, antibacterial, and anti-cancer activities.…”

“…The pepsin hydrolysate of salted egg white was reported to have antioxidant and antibacterial activities, which can scavenge DPPH free radicals and inhibit Staphylococcus aureus. [12] Peptides from salted egg white can enhance osteoblast differentiation and anti-osteoporotic activity through the wnt/𝛽-catenin signaling pathway and several key osteogenic transcription factors (such as Runx2 and OPG). [14] Therefore, the preparation of biologically active peptides from salted egg white is undoubtedly an important way for the high-value utilization of waste protein resources.…”