Levan, fructo-oligosaccharides and fructosyl derivatives were formed from sucrose using recombinant leavansucrase from Rahnella aquatilis. Levan formation was optimal at 30 degrees C resulting 57% of the theoretical yield. The more suitable substrate concentration from levan formation was 200 g sucrose/L. Oligosaccharides was accumulated selectively at high substrate concentration. The increase of levan and oligosaccharides formation was not achieved by adding water-miscible organic solvent. Alkyl fructosides were synthesized from various alcohols as fructosyl acceptors by R. aquatilis levansucrase.