Structure and property changes of soybean protein isolates resulted from the glycation and cross-linking by transglutaminase and a degraded chitosan

Abstract

Structure and property changes of soybean protein isolates resulted from the glycation and cross-linking by transglutaminase and a degraded chitosan Cambios en la estructura y en las propiedades del aislado de proteína de soja como resultado de la glicación y reticulación mediante transglutaminasa y chitosán degradado A glycated and cross-linked soybean protein isolate (GC-SPI) with the glucosamine content of 19.40 g/kg protein was prepared by using SPI, transglutaminase, and a degraded chitosan under fixed conditions, aiming to assess modified properties and potential application of GC-SPI. GC-SPI has less reactable -NH 2 groups than SPI (0.38 versus 0.48 mol/kg protein), and is verified by electrophoretic analysis to be a glycated and cross-linked protein product. Infrared spectroscopy and circular dichroism analyses demonstrate that GC-SPI contains more -OH groups, and has a more open secondary structure. In comparison with SPI, GC-SPI has higher surface hydrophobicity but lower in vitro digestibility due to protein cross-linking, and exhibits greater water-and oil-binding capacities (9.9 versus 6.4 and 3.7 versus 2.0 kg/kg protein). It is concluded that the glycation and cross-linking confer an open structure and modified properties of SPI, and GC-SPI is a potential ingredient with better hydration and oil-binding than SPI.Keywords: soybean protein isolate; degraded chitosan; transglutaminase; secondary structure; property Se preparó aislado de proteína de soja glicada y reticulada (GC-SPI) con un contenido de glucosamina de 19,40 g/kg de proteína utilizando SPI, transglutaminasa y chitosán degradado sometido a condiciones determinadas con el objetivo de estudiar las propiedades modificadas y las aplicaciones potenciales de GC-SPI. GC-SPI obtuvo menos grupos reactivos de tipo NH 2 en comparación con SPI (0,38 frente a 0,48 mol/kg de proteína) y se verificó mediante análisis electroforético para ser un producto proteínico glicado y reticulado. La espectroscopía infrarroja y el análisis de dicroísmo circular mostraron que el GC-SPI contiene más grupos OH y tiene una estructura secundaria más abierta. En comparación con SPI, GC-SPI tiene una mayor superficie de hidrofobia aunque una menor digestibilidad in vitro debido a la reticulación proteínica, además exhibe una mayor capacidad de retención de agua y de aceite (9,9 frente a 6,4 y 3,7 frente a 2,0 kg/kg de proteína). En conclusión, la glicación y la reticulación conceden una estructura abierta y unas propiedades modificadas en SPI. Además GC-SPI se trata de un ingrediente potencial con una mejor hidratación y capacidad de retención que SPI.Palabras clave: aislado de proteína de soja; chitosán degradado; transglutaminasa; estructura secundaria; propiedad

Construction of Polymer Electrolyte Based on Soybean Protein Isolate and Hydroxyethyl Cellulose for a Flexible Solid-State Supercapacitor

“…However, the application remains substantially limited due to the high-water sensitivity, undesirable processability, and inferior mechanical strength [36]. A lot of investigations on modification of SPI have been carried out to solve the problems mentioned above [37,38,39]. In our previous work, a series of crosslinked membranes was prepared by SPI crosslinked with ethylene glycol diglycidyl ether (EGDE) as the crosslinker and it was found that the crosslinked structure could improve the water resistance of SPI/EGDE membrane, but it also reduced the ionic conductivity of the pure SPI film and electrochemical performance of the supercapacitor [40].…”

Changes in the structure, digestibility and immunoreactivities of glycinin induced by the cross‐linking of microbial transglutaminase following heat denaturation

“…IgE and IgG antibodies produced by allergic individuals can specifically recognise linear or conformational epitopes exhibited by the allergen molecule. Zhu et al (2015) suggested that a lower in vitro digestibility of soy protein isolate (SPI) was observed after incubated with MTG and a degraded chitosan. Zhu et al (2015) suggested that a lower in vitro digestibility of soy protein isolate (SPI) was observed after incubated with MTG and a degraded chitosan.…”

“…Moreover, a main characteristic of many food allergens is the resistance to gastric digestion, and digestibility analysis has been regarded as an important method to evaluating the allergenic potential of protein (Lang et al, 2015). Zhu et al (2015) suggested that a lower in vitro digestibility of soy protein isolate (SPI) was observed after incubated with MTG and a degraded chitosan. Therefore, it is necessary to evaluate the effect of MTG-induced modifications on the digestibility and immunoreactivity of glycinin.…”

Rheological, sensory, and microstructural properties of fresh and frozen/thawed mashed potatoes enriched with different proteins

“…In this regard, Álvarez, Fernández, and Canet (2009) and Fernández, Canet, and Alvarez (2009) reported that the addition of kappa-carrageenan (κ-C) and xanthan gum (XG) at a low concentration (1.5 g/kg) to MP could improve the overall acceptability (OA) and minimize damage arising from freezing and thawing. Additionally, the effect of soybean protein isolate (SPI), which contains 90% protein and usually used in the food industry (Zhu, Liu, Fu, & Zhao, 2016), on physicochemical, functional and sensory characteristics of MP products has been reported. Obtained results showed that SPI concentrations had a significant impact on rheological properties of MP (Álvarez, Fernández, Olivares, & Canet, 2012).…”