Moringa oleifera L. Screening: SFE-CO2 Optimisation and Chemical Composition of Seed, Leaf, and Root Extracts as Potential Cosmetic Ingredients

Moringa oleifera L. tree (Mo) has emerged as a rich alternative source of bioactive compounds to design cosmetic formulations. Supercritical carbon dioxide fluid extraction (SFE-CO2) was successfully applied on the screening of Mo seed, leaf, and root extracts. The extraction yield was evaluated by response surface methodology (RSM), for pressure and temperature ranges of 117-273 bar and 41-60 ?, respectively, using a design of experiments (DOE). The pressure significantly affected the results (a=0.05), with the highest extraction efficiency obtained at conditions above 195 bar. The extracts' composition, evaluated by gas chromatography-mass spectrometer (GC-MS), revealed an increasing correlation between the pressure, total extract solubility, and mass of extract at a constant temperature, due to the higher extraction yield. Seed extracts presented more than 80% of oleic acid in relative composition (8.04 mg(compound).g(plantpart)(-1)). Leaf extracts performed well for the obtainment of linolenic acid (>20%; 3.10 mg.g(-1)), nonacosane (>22%; 0.46 mg.g(-1)), and a-tocopherol (>20%; 0.21 mg.g(-1)). Mo root resulted in higher relative composition for sterol molecules, despite its very low affinity with CO2. The most promising bioactive compounds, oleic acid and a-tocopherol, were more abundant when operating at 250 bar at 45? and 195 bar at 55 ?, for Mo seed and leaf SFE-CO2 extracts, respectively.