Adsorption of bile salts to milk phospholipid and phospholipid-protein monolayers.
The adsorption of bile salts to milk phospholipid and phospholipid-protein monolayers at the air-water interface was studied under simulated intestinal conditions using a Langmuir trough, epifluorescence microscopy, and atomic force microscopy. Surface pressure changes were affected by temperature, initial surface pressure, and bile composition. The rate of addition of bile salts and the initial surface pressure of the monolayers had an impact on the microstructure of the mixed monolayers. The presence of proteins in monolayers at different ratios did not affect the surface pressure change upon addition of bile. However, at 20 °C, the addition of bile to phospholipid and phospholipid-protein monolayers led to different features with branching and clustering of liquid-ordered domains and possible formation of bile salt-rich areas within liquid-ordered domains. This study provides a basic understanding of the interfacial changes occurring at the surface of milk fat globules and milk phospholipid liposomes during their passage in the duodenum.
Riddet Institute, Massey University , Private Bag 11 222, Palmerston North 4442, New Zealand.
Sophie
S
Gallier
Ethan
E
Shaw
Andrea
A
Laubscher
Derek
D
Gragson
Harjinder
H
Singh
Rafael
R
Jiménez-Flores
D000327:Adsorption; D000818:Animals; D001647:Bile Acids and Salts / Q000737:chemistry*; D006017:Glycolipids; D006023:Glycoproteins; D066292:Lipid Droplets; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence; D008892:Milk / Q000737:chemistry*; D008894:Milk Proteins / Q000737:chemistry*; D010743:Phospholipids / Q000737:chemistry*; D011312:Pressure; D013499:Surface Properties; D053835:Unilamellar Liposomes / Q000737:chemistry / Q000378:metabolism
D001647:Bile Acids and Salts; D006017:Glycolipids; D006023:Glycoproteins; D008894:Milk Proteins; D010743:Phospholipids; D053835:Unilamellar Liposomes; C110367:milk fat globule