Physicochemical properties, antioxidant activities and in vitro sustained release behaviour of co-encapsulated liposomes as vehicle for vitamin E and β-carotene

BACKGROUND: In this study the potential of liposomes as a vitamin E (VE) and beta-carotene (beta C) delivery system was examined. The co-encapsulated liposomes of beta C and VE (L-VE-beta C) were prepared and characterized. Their antioxidant properties were evaluated by free radical scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), hydroxyl radical and lipid peroxidation assay. The in vitro sustained release behaviour was then investigated and discussed. RESULTS: VE and beta C were co-encapsulated in liposomes with high encapsulation efficiency, up to 92.49% and 86.16% for beta C and VE, respectively. The antioxidant activities of L-VE-beta C samples were significantly higher than that of single loaded liposome. Among different ratios of VE/beta C, L-VE-beta C at 5:3 exhibited the highest radical scavenging rates, with 66.80%, 56.58% and 34.39% for DPPH, ABTS and OH radical, respectively. L-VE-beta C samples also had a good ability to inhibit lipid peroxidation, especially the sample with ratios of VE/beta C at 5:3 and 3:1. In simulated gastrointestinal release, L-VE-beta C exhibited an excellent sustained release behaviour in SGF with the accumulated rate at about 20%, while the release rate in SIF increased to over 80%, where they should be absorbed. The release kinetics analysis indicated that beta C was released in the Higuchi model in stomach, and the Korsmeyr-Peppas model in intestine. CONCLUSION: Compared to single loaded liposomes, the combined-loaded liposomes exhibited higher antioxidant activity and bioavailability, suggesting the potential applications in functional foods. (C) 2022 Society of Chemical Industry.

Automated summary

The study found that co-encapsulated liposomes have higher antioxidant activity and bioavailability compared to single loaded liposomes, especially in potential applications in functional foods.