الخلاصة:
This work is a bibliographic synthesis, which deals with structural characterization and the physico-chemical and biological properties of polysaccharides extracted from medicinal plants in arid areas. In the first chapter, we discussed on polysaccharides and their classification according to their origin, we distinguished the polysaccharides of animals, microorganisms and plants. In the second chapter of this work, plant polysaccharides are highlighted, where most of the polysaccharides of the vegetable cell are either starch, which constitute the storage material of the cell, or those, cellulose, Hemicelluloses and pectins, which constitute the structural components of cell wall. There are also gums that are secreted by defined plant organs in response to special stimuli such as injuries. These plant polysaccharides representing a diversified group of carbohydrates with a complex structure and interesting biological activities. As for the third chapter, which is the most important part in this work, it included polysaccharides from medicinal plants in arid areas, their biochemical composition and their biological activities. We reported 14 genres with these characteristic species, which are: Acacia, Plantago, Astragalus, Retama, Cassia, Melilotus, Trigonella, Malva, Medicago, Nitraria, Opuntia, Phoenix, Zizyphus, Argania. These polysaccharides have shown many biological activities such as: antioxidant, anti-inflammatory, prebiotic and anti-cancer activity.
