Structure of fructo-oligosaccharides from leaves and stem of Agave tequilana Weber, var. azul

Abstract Fructo-oligosaccharides (FOSs) of a six year old agave plant variety, Agave tequilana , were isolated and fractionated by 2D preparative chromatography (SEC and rpHPLC). Structural analyses of different FOS-fractions were performed by reductive methylation analysis connected to GC/FID identification and NMR-analysis. FOSs from leaves (d.p. 3–8) contain single α- d -Glc p residues as well in terminal as internal position, however (2 → 1)-linked β- d -Fru f residues only. FOSs from stem, however, contain as well (2 → 1)- and (2 → 6)-linked β- d -Fru f residues with branched oligomeric repeating units. These characteristics indicate an enzymatically catalyzed metabolic regulation for the biosynthesis and transformation of fructans in A. tequilana which strongly depends on location and transport activities.