Method of producing proanthocyanidin oligomer

摘要

Disclosed is a composition containing a proanthocyanidin oligomer to the terminal of which epicatechin (EC) has been bonded and reduced in the molecular weight, and a proanthocyanidin oligomer to the terminal of which epigallocatechin gallate (EGCG) has been bonded and reduced in the molecular weight, which is obtained by heating plant materials containing proanthocyanidin polymer with green tea or extract thereof in an acidic aqueous solution. The method for producing the above composition is also disclosed. Also disclosed is the use of the said proanthocyanidin oligomer in the production of a composition for the treatment/prevention of lifestyle related diseases caused by generation of reactive oxygen species and brain diseases or for prevention of aging.