Stable vesicle self-assembled from phospholipid and mannosylerythritol lipid and its application in encapsulating anthocyanins

Stable vesicles were formulated based on the self-assembling of L-alpha-phosphatidylcholine (PC) and mannosylerythritol lipid-A (MEL-A) in a manner of weak or non-cooperative interactions. Their structural characterization, stability and encapsulation properties were evaluated. The results showed that the predominant average diameters varied ranging from 200 nm to 700 nm with MEL-A/PC ratio changed. In case of the ratio at 5:5, 6:4 or 7:3, the vesicles performed the smaller size or turbidity and larger entrapment efficiency for hydrophilic molecules. Anthocyanins were successfully encapsulated using these vesicles, which was confirmed by the formation of egg-shaped structures with the core size less than 500 nm and an encapsulation efficiency of 54.9 +/- 1.6%. Compared with free anthocyanins, the encapsulated anthocyanins displayed higher retention rates when exposed to storage and simulated gastrointestinal fluid conditions, and their antioxidant capacity after simulated intestinal digestion was enhanced by 3-3.5 times because of protection of vesicle encapsulation and possible synergic effects.