Conjugation of Soybean Proteins 7S/11S Isolate with Glucose/Fructose in Gels through Wet-Heating Maillard Reaction (2025)

Gelation Enhancement of Soy Protein Isolate using the Maillard Reaction and High Temperatures

Journal of Food Science, 1994

ABSTRACTSoy protein isolate gels prepared by autoclaving solutions in the presence of xylose of glucono‐δ‐lactone (GDL), were compared. In both cases, the pH decreased from neutral to pH 5.5 during gel formation. In the xylose systems, this pH decrease was a consequence of the Maillard reaction. The Maillard gels showed less syneresis, had a higher breaking force and were more elastic, as determined by stress relaxation, then the GDL gels. The differences were attributed to formation of additional covalent crosslinks due to the Maillard reaction, as evidenced by greatly reduced solubility in sodium dodecyl sulfate +β‐mercaptoethanol.

Isolation and Characterization of the Multiple 7S Globulins of Soybean Proteins

Plant Physiology, 1975

Two major proteins (the 7S and 11S globulins) of soybean (Glycine max) were simultaneously isolated by a simple method based on their different solubilities in dilute tris (hydroxymethyl)aminomethane buffers. The purified 7S globulins, which represented essentially the entire 7S soybean protein fraction capable of dimerization at 0.1 ionic strength, were fractionated into five components by diethylaminoethyl Sephadex A-50 column chromatography. The five 7S components were characterized by disc-electrophoresis.

Expression of the sucrose binding protein from soybean: Renaturation and stability of the recombinant protein

Phytochemistry, 2007

The sucrose binding protein (SBP) belongs to the cupin family of proteins and is structurally related to vicilin-like storage proteins. In this investigation, a SBP isoform (GmSBP2/S64) was expressed in E. coli and large amounts of the protein accumulated in the insoluble fraction as inclusion bodies. The renatured protein was studied by circular dichroism (CD), intrinsic fluorescence, and binding of the hydrophobic probes ANS and Bis-ANS. The estimated content of secondary structure of the renatured protein was consistent with that obtained by theoretical modeling with a large predominance of b-strand structure (42%) over the a-helix (9.9%). The fluorescence emission maximum of 303 nm for SBP2 indicated that the fluorescent tryptophan was completely buried within a highly hydrophobic environment. We also measured the equilibrium dissociation constant (K d ) of sucrose binding by fluorescence titration using the refolded protein. The low sucrose binding affinity (K d = 2.79 ± 0.22 mM) of the renatured protein was similar to that of the native protein purified from soybean seeds. Collectively, these results indicate that the folded structure of the renatured protein was similar to the native SBP protein. As a member of the bicupin family of proteins, which includes highly stable seed storage proteins, SBP2 was fairly stable at high temperatures. Likewise, it remained folded to a similar extent in the presence or absence of 7.6 M urea or 6.7 M GdmHCl. The high stability of the renatured protein may be a reminiscent property of SBP from its evolutionary relatedness to the seed storage proteins.

Effect of Conventional Humid–Dry Heating through the Maillard Reaction on Chemical Changes and Enhancement of In Vitro Bioactivities from Soy Protein Isolate Hydrolysate–Yeast Cell Extract Conjugates

Foods, 2024

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Food Processing Characteristics of Soybean 11S and 7S Proteins

Agricultural and Biological Chemistry, 1969

This paper deals with the contribution of protein components in soybean seeds to the physical properties of tofu-gel. Results obtained in tofu-making, using crude 11S and 7S components from defatted soybean meal, indicated that there presented significant difference between tofu-gels from crude 11S and 7S, namely, the tofu-gel from crude 11S was remarkably harder than that from crude 7S. And it has been recognized that the proportion of 11S to 7S in total protein of soybean seeds considerably differed among varieties and that the difference of the proportion might be related to the physical properties of tofu-gel prepared.

Food Processing Characteristics of Soybean Proteins

Agricultural and Biological Chemistry, 1971

Relation between sulfhydryl groups in soybean proteins and the physical properties of tofu was studied. Changes in the amount of sulfhydryl groups by heating or treatment with urea were more rapid in 11S protein as compared with 7S protein. Moreover, by changing the amount of sulfhydryl groups in proteins by N-ethylmaleimide, 2-mercaptoethanol and dithiothreitol, the physical properties of tofu from 11S protein were more significantly effected than that from 7S protein. Namely, tofu-gel from 11SS protein got harder and stronger as the amount of sulfhydryl groups increased. The results may suggest that tofu prepared from 11S protein has more disulfide bonds in its gel than that from 7S protein.

FOOD USE OF SOYBEAN 7s AND 11s PROTEINS Extraction and Functional Properties of Their Fractions

Journal of Food Science, 1973

Gelation of Soybean Protein Isolates in Acidic Conditions. Effect of pH and Protein Concentration

Journal of Agricultural and Food Chemistry, 1995

Heat-induced gels were obtained from acidic and pH 8.0 soybean protein isolates, a t different pH values and protein concentrations. The isolates were characterized through solubility assays in different extraction media, and bidimensional SDS-PAGE, scanning electron microscopy and waterholding capacity were performed to analyze gels. Results indicate that acidic gels became more aggregated when the pH approached the PI. Gels obtained a t acidic pH were different from those obtained at pH 8.0, the latter having more interchain disulfide bonds and different protein species involved in the maintenance of the structure.

Enzymatically modified Soy Protein

Journal of Thermal Analysis and Calorimetry, 2000

Optimum temperature and pH for the isolation of soy protein isolate (SPI) from soy protein concentrate (SPC) were established. Enzymatic hydrolysis of SPI with enzymes of different specificities such as trypsin, chymotrypsin, papain and urease was carried out and the products of hydrolysis were characterized by molecular mass determination [sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)] and thermal techniques [differential scanning calorimetry (DSC) and thermogravimetric analysis (TG)]. Enzymatic hydrolysis resulted in a significant reduction in molecular masses. However the thermal stability of hydrolysed SPI was similar to native SPI indicating that it is independent of molecular mass. DSC studies indicated an increase in temperatures of endothermic transition associated with SPI denaturation and loss of absorbed moisture in samples of lower molecular masses.

Soyabeans as Bioreactor For Biopharamaceuticals And Industrial Proteins: A Review

The production of a large number of recombinant proteins is in high demand, both for scientific evaluation and product development. Furthermore, current treatments that use recombinant proteins plays significant role on strain and health systems in developing and developed countries. In developing countries, cost is the main constraint for most of the population. The use of plants provides an additional alternative to bacterial and mammalian cell based recombinant protein production systems. In some cases, the use of plants may determine whether an effective cancer antigen, a microbicide against HIV, may be economically viable for a biopolymer to reach the market. In this case seeds are very efficient production system and have special compartments for storing proteins. These characteristics may provide the seeds to produce a very efficient system for the large-scale production of recombinant proteins at an economically viable cost. Existing tools, including synthetic biology and metabolic engineering, should expand even further the ability to manipulate seeds to produce recombinant proteins. The studies presented in this article indicate that the seeds are capable of producing recombinant proteins with various biochemical characteristics at high levels. Specific bioassays have demonstrated the functional activity of the recombinant protein produced. Plant bioreactors are attractive expression systems for the economic production of pharmaceuticals. Soybean is an excellent protein producer in the plant crop. Soybean plants are also a good source of abundant and cheap biomass and can be cultivated under controlled greenhouse conditions. There is a lot of potential to bring this is an important step in the development of genetically engineered products that are affordable and safe for medicinal, food and other uses.