コール酸塩類とモノグリセリドによる油脂の乳化と油-水界面張力

油脂の腸管内乳化・吸収の界面科学的考察

抄録

The metabolism of lipids in the intestines was studied in vitro on their surface. Interfacial tension between lipids and water is depressed by adsorption of bile salts at the lipid-water interface. During triglyceride hydrolysis, the fraction of monoglyceride at this interface increases, leading to additional depression of interfacial tension and the formation of a fine lipid dispersion. The interfacial tension of lipid-water is minimum at optimum HLB (hydrophile lipophile balance) of mixed emulsifiers. With further hydrolysis, the monoglyceride fraction at the interface becomes larger, leading in turn to greater interfacial tension. Fine emulsion droplets produced on decreasing the interfacial tension to 0.50.3mN·m^-1, may be adsorbed on the intestinal wall when the HLB of the adsorbed amphiphile layer becomes lipophilic. This is because an amphiphile aggregate disperses water when it is hydrophilic, but forms an amphiphile phase when the hydrophile lipophile property is balanced or lipophilic. After absorption of emulsion droplets, triglyceride may form by esterification of glycerides. Thus, the HLB of mixed amphiphiles may become hydrophilic, and bile salts may dissolve into the blood and recirculate.