Effect of reverse micelle on conformation of soy globulins: A Raman study

Structural characteristics, techno-functionalities, innovation applications and future prospects of soybean β-conglycinin/glycinin: a comprehensive review

The structural molecules and conformational variations of soybean β-conglycinin/glycinin are crucial in defining the characteristics of protein-based foods. Recently, significant attention has been focused on the characteristics of soybean β-conglycinin/glycinin across various fields, particularly their structure and application. The research contributes to expanding the application fields of soybean protein-related component in food industry. This research generally concerned on, but not limited to, the novel substitution of animal-originated foods based on globulins and the deeper precising protein nutrition support. Furthermore, the innovative applications and future development of soybean globulins are presented, focusing on plant-based substitutes and advanced materials. This paper provides a comprehensive review of soybean β-conglycinin/glycinin, focusing on structural characteristics, techno-functionalities, innovation applications, and future prospects, supported by diverse citation and analyses. Additionally, the article introduces various methods for modifying soybean globulins, including physical, chemical, and biological treatments. Furthermore, the innovative applications and future development of soybean globulins are presented, focusing on plant-based substitutes and advanced materials. Despite extensive discussion on globulin applications in diverse food forms, the discourse on their flavor and safety is insufficient. Addressing these limitations is essential for a comprehensive understanding and effective utilization of soybean globulins.

Structure of yuba films at the air/liquid interface as effected by the interfacial adsorption behavior of protein aggregates

The effects of adsorption behavior and assembly mechanism of proteins and lipids at the interface on the formation of yuba films were investigated. The thickness of yuba films increased rapidly from nano to micro scale within minutes according to the scanning electron microscopy (SEM) images. The confocal laser scanning microscope (CLSM), SEM images, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the formation of protein aggregates (40-100 nm) was an essential requirement for the development of yuba. Meanwhile, a relatively loose spatial structure was formed by protein aggregates under the influence of water vapor. This structure served as the foundation for incorporating lipids. Interfacial adsorption kinetics indicated that increasing the concentration (from 3 to 9 mg/mL) of protein aggregates enhanced the rearrangement rate. This finding demonstrated that the variations of interfacial protein aggregate concentration were a crucial factor leading to the non-linear growth of film thickness.

Microstructural Analysis of Whey/Soy Protein Isolate Mixed Gels Using Confocal Raman Microscopy

This work explores the potential of confocal Raman microscopy to investigate the microstructure of mixed protein gel systems. Heat-set protein gels were prepared using whey protein isolate (WPI), soy protein isolate (SPI), and mixtures thereof, with a total of five different whey-to-soy protein ratios (100, 75, 50, 25, and 0%). These were analysed using confocal Raman microscopy, and different data analysis approaches were used to maximize the amount of structural and compositional information extracted from the spectral datasets generated, including both univariate and multivariate analysis methods. Small spectral differences were found between pure WPI and SPI gels, mainly attributed to conformational differences (amide bands), but SPI exhibited considerably greater auto-fluorescence than WPI. The univariate analysis method allowed for a rapid microstructural analysis, successfully mapping the distribution of protein and water in the gels. The greater fluorescence of the capsule-like structures found in the mixed gels, compared to other regions rich in proteins, suggested that these may be enriched in soy proteins. Further analysis, using a multivariate approach, allowed us to distinguish proteins with different levels of hydration within the gels and to detect non-proteinaceous compounds. Raman microscopy proved to be particularly useful to detect the presence of residual lipids in protein gels.

Isolation, process optimisation and characterisation of the protein from the de-oiled cake flour of Madhuca latifolia

This work reports the isolation of the protein from the flour of an underutilised agro waste, a de-oiled cake of Madhuca latifolia using the bis (2-ethylehexyl) sodium sulfosuccinate salt reverse micelle and the characterisation of the protein through various techniques. The experimental conditions for the extraction were optimised using Box-Behnken design. The highest yield of the protein was achieved when the extraction parameters, i.e. KCl concentration, KCl amount, and pH of the medium, were 0.5 M, 1.25 ml, and 9.02, respectively. The experimental yield (75.56%) obtained under the optimised conditions matched extremely well with the predicted yield (75.19%). The analysis of the biochemical composition envisaged the occurrence of 2S albumin, 7S globulin, and 11S globulin as the major components in the protein. The X-ray diffraction pattern supported the β-sheets structure of the protein. The imaging of the protein through a scanning electron microscope revealed the shape and surface of the protein to be spherical and smooth, respectively. Thus, the protein isolate of the de-oiled cake flour of Madhuca latifolia could be utilised towards food product development and relevant fields.

Determination of the domain structure of the 7S and 11S globulins from soy proteins by XRD and FTIR

BACKGROUND

The 7S and 11S fractions from soybean proteins have interesting high nutritional and excellent functional properties. The aim of this research was to improve the functional properties of soy proteins by studying the effect of bis(2-ethylhexyl) sodium sulfosuccinate (AOT) reverse micelles on the conformation of the 7S and 11S globulins using Fourier transform infrared and X-ray diffraction spectroscopy.

RESULTS

Fourier transform infrared revealed that the intensity of the 7S and 11S globulin bands from AOT reverse micelle extraction at 1600-1700, 1480-1575, 1220-1300, 3330, 1448 and 1395 cm(-1) was higher than from aqueous buffer. X-ray diffraction data showed that the intensities of 7S globulin using two extraction methods at 2θ about 10° were significantly different (P < 0.05), about 22° slightly increased. The intensities of 11S globulin at 2θ about 10° and 22° were similar. The average distance between particles (dhkl ) for 7S globulin with aqueous buffer extraction at 2θ about 10° was greater than AOT reverse micelle extraction.

CONCLUSION

This study showed the potential of reverse micelles as a protocol for extracting the 7S and 11S globulins for analytical purposes. The results represent a new avenue for determining the structures of the 7S and 11S globulins.

Raman micro-spectroscopic analysis of cultured HCT116 colon cancer cells in the presence of roscovitine

Raman micro-spectroscopic analysis of cultured HCT116 colon cancer cells in the presence of roscovitine, [seliciclib, 2-(1-ethyl-2-hydroxy-ethylamino)-6-benzylamino-9-isopropylpurine], a promising drug candidate in cancer therapy, has been performed for the first time. The aim of this study was to investigate modulations in colon cancer cells induced by roscovitine. Raman spectra of the cultured HCT116 colon cancer cells treated with roscovitine at different concentrations (0, 5, 10, 25 and 50 μM) were recorded in the range 400-1850 cm(-1). It was shown that the second derivative profile of the experimental spectrum gives valuable information about the wavenumbers and band widths of the vibrational modes of cell components, and it eliminates the appearance of false peaks arising from incorrect baseline corrections. In samples containing roscovitine, significant spectral changes were observed in the intensities of characteristic protein and DNA bands, which indicate roscovitine-induced apoptosis. Roscovitine-induced apoptosis was also assessed by flow cytometry analysis, and analysis of propidium iodide staining. We observed some modifications in amide I and III bands, which arise from alterations in the secondary structure of cell proteins caused by the presence of roscovitine.

Surface characterization of 7S and 11S globulin powders from soy protein examined by X-ray photoelectron spectroscopy and scanning electron microscopy

In this study the surface composition of 7S and 11S globulin powders from soybean proteins by aqueous buffer and reverse micelle extractions had been examined using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Analysis by XPS revealed that the O and N atomic percentage of 7S and 11S globulin surfaces from bis(2-ethylhexyl) sodium sulfosuccinate (AOT) reverse micelle was higher than from aqueous buffer, but the C atomic percentage was lower. The O/C ratio of the 7S globulin powder from aqueous buffer and reverse micelle was similar while significant differences were obtained in the O/C ratio of the 11S globulin powder, N/C atom ratios of the 7S and 11S globulin powders and high-resolution XPS C 1s, N 1s, O 1s spectra. Powder microstructure after reverse micelle treatment showed the presence of small pores, indicating the effect of reverse micelle on the 7S and 11S globulin structure. The obtained results indicated that the reverse micelle could affect the C, O and N components on the surface of soybean proteins.