Structural and rheological properties of mung bean protein emulsion as a liquid egg substitute: The effect of pH shifting and calcium

The use of curcumin in the food industry is constrained by its poor aqueous dispersibility and instability. Previous studies have shown that stable curcumin nanoparticles can be prepared using a pH-driven method. In this study, the nanoencapsulation of curcumin by soybean protein isolate (SPI) was achieved using the pH-driven method. The effect of final pH on SPI and SPI-curcumin (SPI-Cur) nanocomposites was determined by analyzing the encapsulation efficiency and stability. SPI had a high encapsulation efficiency for curcumin and was stable, especially at pH 7 and 8. The formation mechanisms of SPI and SPI-Cur were further determined by molecular docking and multispectral analyses. The results showed that hydrogen bond acceptors (O−) of curcumin under alkaline media interacted with the donor groups (N–H) of amino acids to form hydrogen bonds. Throughout the process, hydrophobic interactions promoted the formation of the nanocomposites, and curcumin had a strong static fluorescence quenching effect on SPI. Furthermore, CD spectroscopy demonstrated that the pH-driven method altered the secondary structure of the SPI. This study provides evidence for the interaction mechanism between curcumin and SPI at different pH-driven stages and indicates SPI-Cur can be used as a delivery system of hydrophobic nutraceuticals.

Entrapment of curcumin in soy protein isolate using the pH-driven method: Nanoencapsulation and formation mechanism

The use of curcumin in the food industry is constrained by its poor aqueous dispersibility and instability. Previous studies have shown that stable curcumin nanoparticles can be prepared using a pH-driven method. In this study, the nanoencapsulation of curcumin by soybean protein isolate (SPI) was achieved using the pH-driven method. The effect of final pH on SPI and SPI-curcumin (SPI-Cur) nanocomposites was determined by analyzing the encapsulation efficiency and stability. SPI had a high encapsulation efficiency for curcumin and was stable, especially at pH 7 and 8. The formation mechanisms of SPI and SPI-Cur were further determined by molecular docking and multispectral analyses. The results showed that hydrogen bond acceptors (O − ) of curcumin under alkaline media interacted with the donor groups (N–H) of amino acids to form hydrogen bonds. Throughout the process, hydrophobic interactions promoted the formation of the nanocomposites, and curcumin had a strong static fluorescence quenching effect on SPI. Furthermore, CD spectroscopy demonstrated that the pH-driven method altered the secondary structure of the SPI. This study provides evidence for the interaction mechanism between curcumin and SPI at different pH-driven stages and indicates SPI-Cur can be used as a delivery system of hydrophobic nutraceuticals. • Stable SPI-Cur nanocomposites were prepared with high encapsulation efficiency. • The final pH value affected the properties of nanocomposites. • Mainly hydrogen bonds and hydrophobic interactions exist in the pH-driven method. • The interaction was altered by structural changes at different pH-driven stages. 

Ball-milling is an effective pretreatment of glycosylation modified the foaming and gel properties of egg white protein

Molecular structural modification of egg white protein by pH-shifting for improving emulsifying capacity and stability

Mild heating (20 °C, 40 °C, 60 °C, and 80 °C) for 1 h assisted pH12 shifting on the structural, physicochemical and functional properties of egg white protein (EWP) were investigated. The results of intrinsic fluorescence, surface hydrophobicity, and free sulfhydryl groups indicated that the tertiary structure depolymerized, the hydrophobic groups exposed and the protein subunits dissociated. Fourier transform infrared spectrophotometer and circular dichroism showed that the content of α-helix decreased, and the content of β-turn increased in the secondary structure of EWP. Moreover, the size and zeta potential of EWP12-80 significantly decreased to 119.17 nm (P

Yu Guan

Papers

Molecular structural modification of egg white protein by pH-shifting for improving emulsifying capacity and stability

Mild heating assisted alkaline pH shifting modify the egg white protein: The mechanism and the enhancement of emulsifying properties

Stability of oil-in-water emulsions improved by ovalbumin-procyanidins mixture: A promising substrate with emulsifying and antioxidant activity.