The invention concerns the use as surface-
active agent of a
fructan N-alkylurethane (I) which is composed of saccharide units of general formula (II)whereinA represents a fructosyl unit (F) or a terminal glucosyl unit (G) of said
fructan, being a levan or an
inulin, with a degree of polymerisation (DP) of minimum 3,(O-CO-NH-R) represents an N-alkylaminocarbonyloxy group replacing a hydroxyl group of the saccharide unit A, wherein R represents a linear or branched, saturated or unsaturated
alkyl group containing from 3 to 22 carbon atoms and any mixture thereof, and s represents the number of N-alkylaminocarbonyloxy groups per saccharide unit which is expressed as
degree of substitution (DS), and said DS has a value
ranging from 0.10 to 2.0. The invention further relates to novel
fructan N-alkylurethanes (I), in particular
inulin N-alkylurethanes (I), and a method for their manufacture. The fructan N-alkylurethanes (I) have good to excellent surface-active properties in combination with good biodegradability and are suitable as surfactants for use in household and industrial applications, e.g. as detergents, emulsifiers,
emulsion stabilizers, foaming agents, foam stabilisers, dispersants and
wetting agents.