Abstract: A polysaccharide-based composition, characterized by comprising or essentially consisting of:at least a first component a) excluding galactane constituted by a substituted .beta.-1,4-linked glycan which is dissolvable in water of a certain temperature and which has a molecular weight (Mw) of .gtoreq.5.multidot.10.sup.4 Daltons, preferably.gtoreq.10.sup.5 Daltons, particularly .gtoreq.10.sup.6 Daltons, andat least a second component b), also excluding galactans, constituted by a substituted .beta.-1,4-linked glycan which is more difficult to dissolve than said first component at said temperature, or is agar or a carrageenan;the use of the composiiton above as a:a) means for reducing friction,b) means for facilitating removal of undesired contamination from surfaces, such as graffiti, scrawl, soot etc.