Effects of Microbacterium laevaniformans Levans Molecular Weight on Cytotoxicity

Levans produced from Microbacterium laevaniformans were isolated, characterized, and fractionated by molecular weight. TLC, HPLC, and GC-MS analyses of the exopolysaccharide showed that it was a fructan-type polymer and was composed of (2,6)- and (2,1)-glycosidic linkages. ∨13C-NMR analysis proved that the polysaccharide was mainly a β-(2,6)-linked levan-type polysaccharide. To investigate the cytotoxicity of the acetone-precipitated levan fractions such as M1, M2, and M3, HepG2, P388D1, U937, SNU-1, and SNUC2A cell lines were screened. Among the cell lines tested, the cytotoxicity of M1-M3 fractions were detected from only SNU-1 and HepG2 cells at the dosage level of 100-800 ㎍/ml.