Diacylglycerol (DAG)/water and triacylglycerol (TAG)/water emulsions were prepared using beta-lactoglobulin (beta-LG) as an emulsifier. The oil phase (20% in emulsion) was mixed with beta-LG solution (1% beta-LG in water, pH 7) to prepare the emulsions. A fine oil-in-water emulsion was produced from both DAG and TAG oils. The interfacial protein concentration of the TAG emulsion was higher than that of the DAG emulsion. The zeta potential of the DAG oil droplet was higher than that of the TAG oil droplet. The front-surface fluorescence spectroscopy results revealed that tryptophan residues in beta-LG moved to the more hydrophobic environment during the adsorption of protein on the oil droplet surfaces. Changes in secondary structure of beta-LG during the adsorption were determined by FT-IR spectroscopy. Decreases in the beta-sheet content concomitant with increases in the alpha-helix content were observed during the adsorption to the oil droplets, and the degree of structural change was greater for beta-LG in the TAG emulsion than in the DAG emulsion, indicating the increased unfolding of adsorbed beta-LG on the TAG oil droplet surface. Results of interfacial tension measurement supported this speculation, that is, the increased unfolding of the protein at the TAG-water interface. Trypsin- and proteinase K-catalyzed proteolysis was used to probe the topography of the adsorbed beta-LG on the oil droplet surface. SDS-PAGE analyses of liberated peptides after the proteolysis indicated the higher susceptibility of beta-LG adsorbed on the DAG oil droplet surface than on the TAG oil droplet surface. On the basis of all the results, we discussed the conformation of the adsorbed beta-LG on the two oil droplet surfaces.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.