Characterization of EDTA-soluble polysaccharides from the scape of Musa paradisiaca (banana)

The polysaccharide components present in the scape of Muse paradisiaca (ban ana) were fractionated into water-soluble (WSP), EDTA-soluble (EDTA-SP), al kali-soluble (ASP) and alkali-insoluble (AISP) polysaccharide fractions [An janeyalu, Jagadish and Raju (1997) Glycoconj. J. 14, 507-512. The EDTA-SP w as further fractionated by iso-amyl alcohol into EDTA-SPA and EDTA-SP-B. Th e homogeneity of these two polysaccharides was established by repeated prec ipitation with iso-amyl alcohol, gel-filtration chromatography and sediment ation analysis. The polysaccharides were characterized by monosaccharide co mposition analysis, methylation linkage analysis, iodine affinity, ferricya nide number, blue value, hydrolysis with alpha -amylase, gold-electron micr oscopy and X-ray diffraction spectroscopy. Data from all of these studies s uggest that EDTA-SP-A is a branched amylose-type alpha -D-glucan and that E DTA-SP-B is a highly branched amylopectin-type polymer. The nature of the b ranching patterns of these polysaccharides suggests that they are unique to M. paradisiaca.