Study on the antioxidant properties of unsaturated fatty acid microemulsions

To enhance the antioxidant properties of unsaturated fatty acids (UFAs), a UFAs microemulsion (UFAs-M) is prepared via direct emulsification. Its storage stability is evaluated using laser diffraction, while the antioxidant properties of both UFAs-M and free UFAs are assessed using the DPPH method. The effects of temperature and UV exposure are also investigated. Over a 90-day period, the mean particle diameter of UFAs-M ranges from 49.1 nm to 57.4 nm, with zeta potential values between -11.79 mV and -13.13 mV. The polydispersity index (PDI) ranges from 0.276 ± 0.045 to 0.319 ± 0.049. The encapsulation efficiency varies from 98.4 ± 0.59% (w/w) to 91.5 ± 0.98% (w/w), and the drug loading ranges from 0.984 ± 0.011% (w/w) to 0.862 ± 0.013% (w/w). The DPPH radical scavenging activity of UFAs-M (82.8 ± 3.15%) is significantly higher than that of UFAs (65.33 ± 0.26%). Moreover, UFAs-M exhibits superior antioxidant performance under high temperature and UV exposure. Overall, the microemulsion system enhances both the antioxidant capacity and storage stability of UFAs, showing promising potential for practical applications.