Unwanted natural and synthetic organic impurities are removed from liquid media contaminated therewith, e.g., liquids and beverages intended for human consumption, or industrial/wastewaters, by introducing into such media a thus effective amount of an optionally modified/insoluble cationic vegetable gum containing one or more cationic or cationizable substituents, maintaining the cationic vegetable gum in such liquid medium until the organic impurities are sorbed thereon, and thence recovering the vegetable gum/sorbed impurities therefrom, whereby purifying the liquid medium.