Astaxanthin encapsulation in nanocapsule by high-pressure homogenization technology: a study on stability, antioxidant activity and in vitro release

The astaxanthin nanocapsules (ASX-LNC) was prepared by high-pressure homogenization technology, the microstructure, stability, antioxidant activity, and in vitro release characteristics of ASX-LNC were characterized and evaluated. The ASX-LNC comprised a core material and wall materials. The core material was composed of astaxanthin oil, and the wall materials were composed of β-cyclodextrin, decapolyglycerol monooleate, soybean lecithin (PC60), glycerol, and deionized water. The mean particle size of the ASX-LNC was 206.9 ± 2.8 nm, and the polydispersity index (PdI) value was 0.218 ± 0.026. The zeta potential of ASX-LNC was −26.16 ± 0.87 mV. The loading amount of ASX-LNC was 0.546%±0.032%, and the encapsulation efficiency was 99.65%±0.13%, indicating that the preparation process was feasible. The stability of ASX-LNC was determined under different conditions, indicating good stability of the ASX-LNC. In antioxidant research, the inhibition rate of free radicals of ASX-LNC was 91.03 ± 0.87% under 250 μg/mL for 30 min, and the inhibition rate of free radicals of astaxanthin ethanol solution was 90.83 ± 1.37%. The antioxidant capacity of astaxanthin was not affected by the encapsulation, which demonstrated the effect of prolonging the release of active ingredients due to the protection of the biological activity of astaxanthin by encapsulation. Compared with the astaxanthin ethanol solution, the ASX-LNC had a slow-release effect and could prolong the action time of active substances. Overall, ASX-LNC is a potential carrier for application in food and health products, which can control the release of active substances.