Effects of Oligoarabinoxylans From Aristida pungens Leaves on Germination and Growth of Barley

Abstract

The objective of this study was to investigate a possible biological activities of oligosaccharides resulting from the hydrolysis of parietal hemicelluloses of the foliar tissue of Aristida pungens. Known for its developed, fiber rich foliar tissue, this perennial grasses is widely distributed on the arid and sub-desertic regions of Algeria. In order to identify added value application for the cell wall hemicellulose of Aristida pungens (Poaceae), the polymers were hydrolyzed enzymatically and after size exclusion chromatography, oligosaccharide fragments were tested for their abilities to modify the germination and growth of barley seeds (Hordeum vulgare). Five fractions were separated with different compositions and molecular weights. The low molecular weight fractions were mostly composed of oligoxylans, while the high molecular weight fractions consisted of oligo-glucuronoarabinoxylans. Biological tests suggested that the oligosaccharide fractions and particularly the low molecular weight fraction could promote germination and increase root bio-mass at low concentrations or reduce it at higher concentrations, suggesting a possible bio-stimulating application.