<；P>；PROBLEM TO BE SOLVED: To provide a method for producing a mutant of Cordyceps militaris (fungi parasitic on a larva) and a method for producing cordycepin in high productivity by using the mutant. <；P>；SOLUTION: Mycelium of Cordyceps militaris is irradiated with high-energy ion beam and a mutant having mycological properties, especially the productivity of a physiologically active substance, different from those of the mother strain is selected from the irradiated mycelia. A mutant capable of producing cordycepin useful as an active component in high efficiency is selected from the selected mutant, and the obtained high productivity strain is cultured under the optimum condition to perform the production of cordycepin in high productivity. <；P>；COPYRIGHT: (C)2009,JPO&INPIT
