Liposomes are widely used as carrier system for bioactive ingredients and usually need to be stabilized by cholesterol. However, the relationship between cholesterol intake and human health has been controversial. The objective of this study was to develop novel multifunctional nanoliposomes stabilized by sea cucumber sulfated sterols via the thin-film hydration method. The liposomes obtained from this study were obviously stable for more than 27 days at 4°C. Astaxanthin was successfully encapsulated by a novel uniform liposome prepared with a mass ratio of egg yolk lecithin to sea cucumber sulfated sterols at 3:1. The mean particle size was 109.53±0.30 nm with 0.241±0.005 polydispersity index and zeta potential value of -21.13±1.01 mV. Astaxanthin-loaded liposome stabilized by sea cucumber sulfated sterols exhibited significantly higher antioxidant activities in terms of DPPH radical-scavenging activity and reducing power than the mixture of astaxanthin and blank sea cucumber sulfated sterols liposome during storage of 6 and 12 days, respectively. The in vivo digestion and absorption results showed that the bioavailability of dietary astaxanthin encapsulated in liposomes could significantly be improved. Being an efficient carrier with multifunctions, the novel liposome stabilized by sea cucumber sulfated sterols had great potential in functional food development and biomedical applications.
Keywords: astaxanthin; bioavailability; cholesterol; liposome; sea cucumber sulfated sterols.