Antioxidant Properties of a Supercritical Fluid Extract of the Halophyte Mesembryanthemum nodiflorum L. from Sicilian Coasts: Nutraceutical and Cosmeceutical Applications

The aim of this paper was to obtain different extracts from the aerial parts of Mesembryanthemum nodiflorum, comparing traditional extraction (using solvents with increasing polarity such as hexane, ethanol 80%, acetone 70% and water) with an eco-friendly technique (supercritical fluid extraction (SFE)); to evaluate which extract showed a higher amount of antioxidants and then evaluate the bioactive properties in vitro, in human fibroblast (HS68). From the six extracts obtained it was observed that the solvent with the highest extraction efficiency was water, but the extracts in ethanol, N-hexane and SFE are those that showed the highest antioxidant activity (polyphenols, 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and reducing power). On the basis of these results, the SFE extract was chosen to evaluate the antioxidant and anti-aging activity in vitro, by assessing cell vitality and molecular markers (MTT and immunoblotting assays). The results showed that the SFE extract exerted antioxidant activity in vitro, protecting cells from mortality induced by oxidative stress; this protection was also confirmed at the molecular level, by the levels of the protein integrin alpha-1, that is able to prevent the negative effects of a stress situation, such as oxidative stress, that could promote aging and related diseases. This extract, obtained with an eco-friendly technique, given its beneficial properties, could be used for application in nutraceuticals and cosmeceuticals.