COMPARATIVE STUDY OF CELL WALL POLYSACCHARIDES PODS AND SEEDS OF Acacia arabica AND Acacia raddiana FROM TAMANRASSET (SOUTHERN ALGERIA)

Acacia arabica and Acacia raddiana from Tamanrasset (southern Algeria) are a bioresource containing several bioactive compounds such as polysaccharide fibers which deserve more attention for their valorization. The main objective of this study is based on a chemical extraction and quantification of cell wall polysaccharides pods and seeds followed by a qualitative analysis by thin layer chromatography to determine their osidic compositions. Using the Stabox 6.1 software, the values obtained have been the subject of a two-factor statistical analysis (ANOVA p = 0.05).

The results obtained (in g / 100 g dry matter) show that the two species of acacia are rich in polysaccharide fibers and there is no significant difference between the two species. By against, there is a significant difference in rates of parietal residues between the pods and seeds of each species is (52.03±0.02, 51.34±0.01) and (43.55±0.01 and 40.75±0.01) respectively. The cell walls are mainly composed of cellulose (25.61±0.01, 24.24±0.01%) and (20.17±0.010 and 16.86±0.01%) respectively between species. The hemicelluloses come in second place (11.60±0.01, 11.40±0.01%) and (9.29±0.13 and 8.47±0.01%), followed by highly methylated pectins (5.04±0.01, 4.95±0.26%) and (3.96±0.0 and 0.01±2.077%) whose content is higher compared to the low-methylated pectin. The TLC showed that the major component of the cellulose is glucose; hemicelluloses are type’s arabinoglucuronoxylane and pectins arabino-galacturonic type.

Keeping account of the diversity and the complexity of the structural polysaccharides contained in lignocellulosic biomass determination of the primary structure of polysaccharides, their three- dimensional organizations and their physicochemical properties may constitute interesting prospects search for better rational exploitation.