Application of Sequential Extraction Using Pressurized Fluids to Obtain Compounds from Leaves.

The aim of this study was to use high-pressure extraction methods to obtain compounds of different classes from the leaves of Mill. For this purpose, Supercritical Fluid Extraction (SFE) and Pressurized Liquid Extraction (PLE) were used. SFE was performed with leaves to evaluate the application of propane and carbon dioxide as solvents, and the residual biomass from this stage was used in PLE with hydroethanolic solvent. The extracts were characterized in relation to the content of phenolic compounds, antioxidant potential and content of nonpolar compounds. In the first stage, despite the low yield (1.09-1.94%) compared to PLE (16.56-19.26%), the extracts presented a high content of lipophilic compounds (squalene, octacosanol, α-tocopherol and β-sitosterol) compared to the PLE technique. The sequential extraction process benefited the greater recovery of phenolic compounds and extracts with greater antioxidant potential. Caffeic and nicotinic acids were the major compounds identified in the phenolic profile. The processes applied did not influence the protein content of the final extraction residue, which was similar to that of the in natura leaf. The results and approach demonstrate that sequential extraction is an excellent alternative for the use of , which allows for the production of extracts with varied composition and/or extracts with greater recovery of compounds available in the plant.