Abstract
The binary phase diagram of γ-gliadin, a wheat storage protein, in water was explored thanks to the microevaporator, an original PDMS microfluidic device. This protein, usually qualified as insoluble in aqueous environments, displayed a partial solubility in water. Two liquid phases, a very dilute and a dense phase, were identified after a few hours of accumulation time in the microevaporator. This liquid–liquid phase separation (LLPS) was further characterized through in situ micro-Raman spectroscopy of the dilute and dense protein phases. Micro-Raman spectroscopy showed a specific orientation of phenylalanine residues perpendicular to the PDMS surfaces only for the diluted phase. This orientation was ascribed to the protein adsorption at interfaces, which would act as nuclei for the growth of dense phase in bulk. This study, thanks to the use of both aqueous solvent and a microevaporator, would provide some evidence for a possible physicochemical origin of the gliadin assembly in the endoplasmic reticulum of albumen cells, leading to the formation of dense phases called protein bodies. The microfluidic tool could be used also in food science to probe protein–protein interactions in order to build up phase diagrams.
Highlights
IntroductionFrom a technological point of view, the behavior of such dough depends tremendously on the process via mechanical shearing, added salt, heat, etc., and a thorough link between the exact composition of wheat storage proteins and technological issues remains to be established [1]
The initial droplets, nucleated at interfaces, gradually detached to form spherical droplets with rough surfaces in the bulk of the capillary. When carrying this experiment with TRITC-labeled proteins, we clearly noticed that the protein solution phase separated (Figure 2A), segregating in dense liquid-like droplets and dispersed species responsible for a non-zero fluorescent background. It suggested a region of coexisting phases and underlying a liquid–liquid phase separation (LLPS)
When carrying this experiment with TRITClabeled proteins, we clearly noticed that the protein solution phase separated (Figure 2A), segregating in dense liquid-like droplets and dispersed species responsible for a non-zero fluorescent background
Summary
From a technological point of view, the behavior of such dough depends tremendously on the process via mechanical shearing, added salt, heat, etc., and a thorough link between the exact composition of wheat storage proteins and technological issues remains to be established [1]. These proteins seem promising in terms of biomaterials and drug delivery systems [2,3,4]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
