Establishment of two-dimensional gel electrophoresis for soybean protein isolate and its application

To optimize the conditions for the establishment of two-dimensional gel electrophoresis(2-DE)of soybean protein isolate(SPI),we investigated Ampholine mixture,anodic and cathodic electrolytes,loading amount of sample,acrylamide concentration,p H gradient and gel staining method in twodimensional gel electrophoresis to optimize the protein imaging conditions in two-dimensional gel.The results of mixed-level design experiments showed that Ampholine,loading amount and gel staining method had significant effect(P<0.05)on 2-DE of SPI.The optimal conditions were Ampholine mixture(pH 3–10+pH 5–7 or pH 4–6+pH 5–7),loading amount of 2 mg sample and silver staining.Although the acrylamide concentration of the gel,the p H gradient,the anodic and cathodic electrolyte solutions had significant statistical effects on the protein separation degree,the complexity of the protein composition and the visibility of the gel images were more inclined to the 12%gel,the 3–10 pH gradient and the H3PO4/NaOH electrolyte.According to the established conditions,the hydrolyzed products of SPI emulsion were determined by 2-DE,and the dynamic changes of protein in the process of enzymatic hydrolysis were described.

Digestion performance improvement of tributyrin through nano-emulsion preparation technology

The current research aimed to optimize the preparation technology of tributyrin nano-emulsion(TBNE)to improve its digestion properties, which were investigated through digestion models in vitro and in vivo. The content of each component of TBNE was optimized by response surface methodology(RSM) to improve the z-average particle size and stability of TBNE. The optimized TBNE was evaluated for its digestion properties by in vitro and in vivo models. The preparation conditions of TBNE optimized by RSM were as follows: 61.3% of sorbitol, 32.7% of tributyrin, and 6.0% of modified phospholipid(MP). The predicted z-average particle size of TBNE was(246.02 ± 18.10) nm. The results of the verification test showed that the z-average particle size, zeta potential, conductivity, emulsification activity index, and emulsification stability index of TBNE were(250.02 ± 7.18) nm,(-40.23 ± 0.76) m V,(31.80 ± 2.09) μS/cm,(848.00 ± 84.53) min and(1.14 ± 0.02) m^(2)/g, respectively. The in vitro digestion experiment results showed that the TBNE remained stable in the stomach and was released in the intestine, while the size of TBNE in the gastrointestinal tact was significantly smaller than that of tributyrin(P < 0.05), which made it easier to be digested and absorbed. Compared with tributyrin treatment, TBNE significantly promoted the average body weight at the 7th day, average daily feed intake,average daily gain, feed/gain, ileum weight, and organ index of ileum of Hy-Line BROWN chicks(P < 0.05), and the butyric acid content in the ileal chyme from TBNE and tributyrin treatment were172.18 mg/m L and 100.85 mg/m L(P < 0.01). Therefore, the established TBNE technology in this study could be supposed to improve the digestion properties of tributyrin.