(2) a cholic acid derivative having the general formula (III) ##STR2## where R4 is a hydrogen atom or a hydroxyl group or a salt thereof; (3) a methylglucan amide having the general formula (IV): ##STR3## where y is an integer of 5 to 7; and (4) n-octyl ??-glucoside, sucrose monocaprate and N-formyl methylleucylalanine.