Abstract: A cyclodextrin adsorbing material composed of a water-insoluble resin substrate to which a ligand having such a size as to be included by cyclodextrin is chemically bonded via a spacer radical; a method of separating and purifying cyclodextrin from an aqueous solution containing it, which comprises bringing said aqueous solution into contact with the above adsorbing material to adsorb cyclodextrin on the adsorbing material, and subjecting the adsorbing material to a desorption treatment to recover cyclodextrin; and a method of increasing the amount of cyclodextrin yielded, which comprises carrying out a cyclodextrin-forming reaction by an enzymatic method in the presence of the above adsorbent material.

Abstract: Partially methylated cyclodextrins with enhanced solubility in water have an average degree of methylation of hydroxyl groups at different positions in all the glucose units involved of about 53-64% for the 2-position, about 38-51% for the 3-position and about 70-100% for the 6-position. The partially methylated cyclodextrins are prepared by reacting .beta.-cyclodextrin with more than about 30 equivalent proportions based on the .beta.-cyclodextrin of dimethyl sulfate and more than about 30 equivalent proportions of an alkali metal hydroxide, wherein the concentration of reactants is greater than 10% (wt/wt).