Patent ID: 7419690

Claim:
A method of enhancing proliferation of bone marrow cells or spleen cells, the method comprising identifying a subject in need of enhancing proliferation of bone marrow or spleen cells and administering to the subject an effective amount of a DsCEII extract from a tuber of a Dioscorea plant, wherein the DsCEII extract is prepared by a process including: a) obtaining an aqueous extract of a tuber of a Dioscorea plant, b) extracting the extract of part (a) with an aqueous solution containing 50% ethanol to form a first supernatant and first ethanol-insoluble fraction, c) extracting said first supernatant of part (b) with an aqueous solution containing 75% ethanol to form a second supernatant and a second ethanol-insoluble fraction and d) collecting said second ethanol-insoluble fraction, wherein the second ethanol-insoluble fraction is DsCEII, and wherein the Dioscorea plant is selected from the group consisting of Dioscorea batatas Decne, Dioscorea alata L., Dioscorea pseudojaponica , and Dioscorea alata L. var. purpurea (Roxb.) M. Pouch.