Optimisation de l’extraction des polyphénols à partir des feuilles de Cupressus sempervirens L.

Abstract

This study aims to optimize the extraction conditions of polyphenols from the cypress tree leaves (Cupressus sempervirens L.) through maceration in methanol, using the central composite design (CCD). The chosen factors for optimization were the plant powder/methanol concentration and the maceration time. The results allowed to determine the optimal conditions to maximize the polyphenol content. The optimal extraction was achieved with a polyphenol content of 152 mg GAE/g, obtained with a powder-to-solvent concentration of 12.67% and an extraction time of 7.28 hours.The optimized methanolic extract was then subjected to phytochemical tests, revealing the presence of polyphenols, alkaloids, mucilages, coumarins, and tannins, but the absence of sterols.Regarding the antibacterial activity of the optimized extract, tests showed a significant activity against the Klebsiella pneumoniae strain. For Escherichia coli, the concentrated extract (100mg/ml) also demonstrated a notable effect. However, relatively low sensitivity was observed for the Staphylococcus aureus and Pseudomonas aeruginosa strains.