Abstract: This study aimed to optimize the preparation conditions of lutein nanoliposomes (LUT-NLP) by ethanol injection method using a combination of one-factor-at-a-time method and response surface methodology. The optimal preparation conditions were found to be as follows: lutein concentration, 0.51 mg/mL; total content of lecithin and cholesterol (4:1, m/m) in nanoliposomes, 5.0%; pH, 7.4; and hydration temperature, 62.9 ℃. Under these conditions, the entrapment efficiency of lutein in nanoliposomes was (91.20 ± 0.56)% and the average size of nanoliposomes was (226.8 ± 10.62) nm. Transmission electron microscope (TEM) showed that the shape of LUT-NLP was regularly spherical and lutein was evenly distributed in the nanoliposomes. The antioxidant activity studies showed that both lutein and LUT-NLP concentration-dependently scavenged 1,1-dipheny1-2-picrylhydrazyl (DPPH) radical. Furthermore, this study demonstrated that LUT-NLP had apparently improved antioxidant activity and stability compared with lutein .

Key words: lutein, nanoliposome, preparation, response surface methodology, oxidative stability