Curcumin as a bioactive component has antioxidant and antibacterial activity
which can be used in various nonpolar food and pharmaceutical formulations. In
this study, oil-in-water curcumin nanodispersions were prepared using a subcritical
water technique. In order to investigate the antioxidant activity and curcumin loss of
the prepared nanodispersions, response surface methodology was applied to assess
influence of operating conditions including temperature (100–140 °C), and heating time (60–180 min). The results, however, indicated that nanodispersions with
minimum curcumin loss (2.65%), maximum antioxidant activity (57.9%) and conductivity (0.36 ms/cm) were produced at optimal operation conditions of 123.03 °C
and 112.12 min. The results also indicated that particle size, PDI and zeta-potential values of the provided nanodispersions at optimum conditions were 17.30 nm,
0.260, and − 12.6 mV, respectively. In addition, loading ability and efficiency
were 0.194 g/L, and 97.35%, respectively. Furthermore, high antibacterial activity
against both Gram-positive and Gram-negative bacteria was achieved at optimum
conditions.