PROBLEM TO BE SOLVED: To obtain a new substance produced by a specific Gram negative bacterium, and capable of decolorizing a colored waste water containing a water soluble dye safely by an extremely simple operation, since it has an activity of binding with the dye dissolved in the water and precipitating and coagulating it from the water.
SOLUTION: This new polysaccharide shows following properties: a ratio of constructing saccharied measured by a gas chromatography and a high performance liquid chromatography: 10-60 wt.% glucuronic acid, 5-70 wt.% glucose, 10-80 wt.% galactose, 5-20 wt. % fucose; elemental analysis values (wt. %): C 37.0-41.0, H 6.0-7.5, O 52.0-56.0; decomposition starting temperature: 200-250°C; molecular weight measured by a high performance liquid chromatography: ≥7×106. The polysaccharide is obtained by culturing a microorganism having a capacity of producing it, preferably Burkholderia KYO-36 strain (FERM BP6468) belonging to the bacteria of the genus Burkholderia, and isolating it from the cultured material or its treated material.