Patent ID: 8846751

Claim:
A method for producing a composition for inhibiting production of hepatitis C virus (HCV), comprising: preparing a proanthocyanidin composition having an anti-HCV production activity value (IC50) which is: less than 0.61 μg/ml, and less than or equal to one tenth of the concentration of the proanthocyanidin composition for inhibiting 50% of cell proliferation (CC50); and comprising a proanthocyanidin having 5 to 10 monomer units, each of which consists of the flavan-3-ol illustrated in the general formula (1): wherein R 1 is hydrogen, R 2 is hydroxyl, R 3 is hydrogen or hydroxyl, R 4 is hydrogen or a gallate group, and n is 5-10; said units of flavan-3-ol being bonded to each other in any one of three bond patterns as follows: (i) the bond between carbon at position 4 and carbon at position 8, (ii) the bond between carbon at position 4 and carbon at position 6, (iii) the bond between carbon at position 4 and carbon at position 8, and between carbon at position 2 and oxygen at position 7; and forming the composition for inhibiting production of HCV comprising the proanthocyanidin composition.