Résumé:
This work is the subject of a phytochemical and biological study of two medicinal
plants belonging to two different families.
1. Crataegus azarolus (L.), belonging to Rosaceae family:
After maceration of the aerial parts of the plant Crataegus azarolus in a methanolic
solution and extraction with solvents of increasing polarity, three extracts are obtained. The
extracts are separated using chromatographic methods of separation and purification, to lead
finally to pure compounds. Then, the GC-MS analysis of a fraction of the CHCl3 extract
allowed us to identify five volatile compounds for the first time from this species by
comparing their mass spectra with the literature (NIST database).
From the AcOEt extract five compounds were isolated, where two acetylated
flavonoid glycosids were identified for the first time from the species.
From the n-BuOH extract, three flavonoid glycosides are separated by CC and TLC.
Their structures are elucidated through spectroscopic analysis methods.
The antioxidant activity of the extracts and compounds is evaluated using five
different methods (DPPH, ABTS, CUPRAC, FRAP and β-carotene).
2. Dioscorea communis (L.) Caddick & Wilkin, belonging to Dioscoreaceae family:
Also, after maceration of the rhizomes of Dioscorea communis in diethyl ether
solvent. The Et2O extract obtained was separated by chromatographic techniques (CC, TLC)
to finally result in several compounds, seven of which are identified by spectroscopic methods
of analyzes (MS, IR, UV, 1D and 2D NMR), where three of them are identified for the first
time from this species.
Et2O, AcOEt Extracts and some isolated compounds have shown an antioxidant
activity by using five different methods (DPPH, ABTS, CUPRAC, FRAP and β-Carrotene),
also these extracts and compounds are tested for the first time against acetylcholinesterase
(AChE) and butyrylcholinesterase (BChE) enzymes. This study confirmed that the presence
of OH groups on the phenanthrene skeleton is essential for its antioxidant and
anticholinesterase activities.
