Acylation modification enhanced encapsulation ability of baicalin by liposome, and liposome improved physicochemical properties and cytotoxicity of baicalin esters

Abstract

The instability of ester bonds, low water solubility, and increased cytotoxicity of flavonoid glycoside esters with fatty chain significantly limit their application in the food industry. Therefore, the present study attempted to resolve these issues through liposome encapsulation. The results showed that the encapsulation and loading efficiencies of baicalin (a representative flavonoid glycoside) butyl ester and octyl ester were much higher than that of baicalin, and the leakage rate of baicalin butyl ester and octyl ester from liposomes was lower than that of baicalin after 60 days of storage at 4°C. The FTIR results revealed the location of butyl ester and octyl ester in the hydrophobic layer of liposomes, which was different from baicalin. Additionally, liposome encapsulation significantly improved the water solubility and stability of baicalin butyl ester and octyl ester in the digestive system and PBS but significantly reduced their toxicity to the L02 cells. Furthermore, the release rate of butyl ester (64.4%) and octyl ester (60.3%) from liposomes was lower than that of baicalin (97.5%) during gastrointestinal digestion. These results indicate that liposome encapsulation could hinder the negative effects of fatty chain introduction into flavonoid glycosides, thereby resolving the deficiency of flavonoid glycoside-loading liposomes.