title: Structural characterization and anticancer activity of cell-bound exopolysaccharide from Lactobacillus helveticus MB2-1.
abstract: A novel cell-bound exopolysaccharide (c-EPS) was isolated from Lactobacillus helveticus MB2-1 by ultrasonic extraction, anion exchange, and gel filtration chromatography before being structurally characterized. The c-EPS is a heteropolysaccharide with an average molecular weight of 1.83 × 10(5) Da and is composed of glucose, mannose, galactose, rhamnose, and arabinose at a molar ratio of 3.12:1.01:1.00:0.18:0.16. Methylation analysis and nuclear magnetic resonance analysis revealed that the c-EPS is a linear glucomannogalactan containing repeating units of → 6)-β-D-Manp-(1 → 3)-β-D-Glcp-(1 → 3)-β-D-Glcp-(1 → 3)-β-D-Glcp-(1 → 4)-α-D-Galp-(1 → and trace amounts of Rhap-(1 → and (1 → 4)-Arap residues. Complex formation with Congo red demonstrated a triple-strand helical conformation for the c-EPS. Scanning electron microscopy of the c-EPS revealed many regular feather-like structural units. Topographical examination of c-EPS by atomic force microscopy revealed that the c-EPS formed rounded-to-spherical lumps with different sizes and chain formations. Furthermore, preliminary in vitro tests revealed that c-EPS significantly inhibited the proliferation of HepG-2, BGC-823, and especially HT-29 cancer cells.
authors: †College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
authors: Wei
authors: W
authors: Li
authors: ‡Institute of Agro-Product Processing, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210095, P. R. China.
authors: Xiudong
authors: X
authors: Xia
authors: †College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
authors: Weizhi
authors: W
authors: Tang
authors: †College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
authors: Juan
authors: J
authors: Ji
authors: †College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
authors: Xin
authors: X
authors: Rui
authors: †College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
authors: Xiaohong
authors: X
authors: Chen
authors: †College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
authors: Mei
authors: M
authors: Jiang
authors: ‡Institute of Agro-Product Processing, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210095, P. R. China.
authors: Jianzhong
authors: J
authors: Zhou
authors: †College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
authors: Qiuqin
authors: Q
authors: Zhang
authors: †College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, P. R. China.
authors: Mingsheng
authors: M
authors: Dong
mesh_terms: D000970:Antineoplastic Agents; D002236:Carbohydrate Conformation; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D019073:HT29 Cells; D056945:Hep G2 Cells; D006801:Humans; D052198:Lactobacillus helveticus / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D008970:Molecular Weight; D009005:Monosaccharides / Q000032:analysis; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D013274:Stomach Neoplasms
chemical_list: D000970:Antineoplastic Agents; D009005:Monosaccharides; D011135:Polysaccharides, Bacterial
keywords: Lactobacillus helveticus MB2-1; anticancer activity; cell-bound exopolysaccharide (c-EPS); structural characterization