Potential of Curcuma zedoaria Hydrosol as an Antioxidant and Active Ingredient for Emulgel

Abstract

...Hydro-distillation of Curcuma zedoaria rhizomes produces essential oils with high antioxidant activity. The distillation process results in a large amount of residue (hydrosol) which are underutilized. Hydrosol contains 0.2% of essential oil which can be harnessed into high value products. This study aimed to assess the antioxidant potential of Curcuma zedoaria hydrosol, as well as its emulgel formulations. Curcuma zedoaria hydrosols were obtained from hydro-distillation at 100℃ for 3 hours. The chemical constituents of the hydrosols were determined by gas chromatography-mass spectrometry (GC-MS). The hydrosol was formulated into emulgels containing different hydrosol concentrations; F1 (30%), F2 (40%), and F3 (50%). The physicochemical properties of the emulgels were evaluated according to standard procedures. Antioxidant activity of both the hydrosol and emulgels was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. The GC-MS analysis showed that the major components of Curcuma zedoaria hydrosols were 1, 4-cineole, bicyclo [2.2.1] heptane, 2-propanone, and 2-propynoic acid. The hydrosol and emulgels demonstrated a concentration-dependent antioxidant activity with IC₅₀ values of 92.31 ± 4.96 g/L, 218.62 ± 22.37 g/L (F1), 159.86 ± 10.46 g/L (F2), and 133.13 ± 25.85 g/L (F3). All three emulgel formulations were yellowish-white semi-solid with a distinctive smell of Curcuma zedoaria and pH between 4.59 – 4.76. All other physical parameters were within acceptable limits. These findings suggest that Curcuma zedoaria hydrosol has great potential to be developed as active ingredient in topical skincare products.