Enhancement of antioxidant and skin moisturizing effects of olive oil by incorporation into microemulsions

Abstract

The aims of the present study were to develop olive oil microemulsions and characterize their antioxidant and skin moisturizing properties. The acid, iodine, and saponification values of olive oil were 0.38 + 0.01 mg potassium hydroxide/g, 88.2 + 5.9 mg iodine/g, and 192.2 + 1.4 mg potassium hydroxide/g, respectively. Pseudoternary phase diagrams, constructed using the water titration method, produced suitable microemulsions: microemulsion 1 (10% olive oil, 64% Tween 85, 16% propylene glycol, and 10% water) and microemulsion 2 (10% olive oil, 64% Tween 85, 16% ethanol, and 10% water). Microemulsions 1 and 2 exhibited Newtonian flow behavior with internal droplet sizes of 443.60 + 27.66 nm and 139.37 + 12.15 nm, respectively. Their in vitro antioxidant and skin moisturizing properties were investigated in comparison with native olive oil. Microemulsion 2 possessed the highest significant antioxidant effect (p < 0.05) giving half maximal inhibitory concentration values in radical-scavenging activity against 1,1-diphenyl-2-picrylhydrazyl and 2,2 0 -azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) of 4.78 + 1.25 mg/mL and 14.85 + 11.18 mg/mL, respectively. The lipid peroxidation inhibition of microemulsion 2 was comparable to native olive oil, whereas the skin moisturizing effect of microemulsion 1 was comparable to the well-known skin moisturizer, hyaluronic acid. In conclusion, microemulsions enhanced both antioxidant and skin moisturizing effects and were attractive formulations for using as a cosmetic or drug delivery system.

Antioxidant and Moisturizing Properties of Carboxymethyl Chitosan with Different Molecular Weights

“…The replacement of -NH groups by -COO groups in the CMCH structure was previously reported to be beneficial not only to level of solubility, but also antioxidant activities [ 43 ]. Although some studies suggested the effects of molecular weights to FRAP antioxidant activities [ 44 ], such effect was not evident in current study.…”

Chemical composition and the anti‐melanogenic potential of different essential oils

“…myrcene and citral) to which the inhibitory effect had been previously ascribed, it is plausible that the anti‐tyrosinase activity of our sample might depend on some other constituents. In this regard, it is worth mentioning that a recent study found a significant anti‐tyrosinase activity in citrus EOs which contained very low levels of myrcene and citral, but was extremely rich in limonene, as was C . aurantium EO 1.…”

Development, characterization and stability of microemulsionated formulations of bacaba, Oenocarpus bacaba oil

“…The higher activity of the formulations relative to the oil dilutions was probably due to the incorporation of the oil into the formulation, which may influence its behavior (Hamed et al 2012;Chaiyana et al 2014). Although the antioxidant activity of the formulations was higher then that of the diluted oil, it was not as high as that of microemulsions with olive oil (Chaiyana et al 2016). The choice of the carrier can either increase or decrease the potential antioxidant activity of the microemulsion, thus the choice of surfactant is important, since these substances may or may not present antioxidant activity when isolated (Kim et al 2009;Pérez-Rosés et al 2014).…”