Research on water soluble polysaccharides separated from skin juice, gel juice and flower of aloe ferox miller

Abstract

Crude water-soluble polysaccharides were isolated from gel juice, skin juice and flowers of Aloe ferox Miller. Result indicated that skin juice contained 15 fold the level of polysaccharides in gel juice from one plant, strongly suggesting the potential industrial application of A. ferox skin as the resource of polysaccharides, rather than discarded. The amount of polysaccharides in the flower of A. ferox was about 2 fold compared with those of A. arborescens and A. vera. After fractionation by anion-exchange chromatography and gel permeation chromatography, gel juice polysaccharide was separated into three neutral (GN1, 1.7%; GN2, 17.6% and GN3, 0.4%) and one acid (GA1, 19.7%) fractions. Skin juice polysaccharide consisted of one neutral (SN1, 25.2%) and two acid (SA1, 7.2%; SA2, 18.0%) fractions. Flower polysaccharide consisted of one neutral (FN1, 1.6%) and one acid (FA1, 26.4%) fractions. All the subfractions have relatively high polydispersity indices (1.0 to 2.5). Sugar analysis shows that the subfractions are constituted predominantly by galactose, glucose and mannose with different mole percentages, except that acidic flower polysaccharide was composed of two more monosaccharides, rhamnose and xylose, and neutral skin juice polysaccharide yielded glucose as the sole monosaccharide. Galacturonic acid was identified as the sole uronic acid in all acidic polysaccharides from different tissues.