Abstract: The antitumor activity of tea catechin oxy- polymers(TCOP)was studied with Ehrlichascites tumor and human hepatic carcinoma cell line(SMMC- 7721); The immunomodulatory effects of TCOP were assayed by delayed type hypersensitivity(DTH), phagocytosing method and LDH method..The result suggested that TCOP strongly inhibited the growth of Ehrlichascites tumor(solid tumor).The inhibitory rate in dose of 200 mg/kg.d and 400mg/kg.d was 47.1% and 36.7% respectively for TCOP and 30.8% and 36.6% for respectively TC. MTT assay showed that the different concentrations of TCOP significantly inhibited the growth of human hepatic carcinoma cell line(SMMC- 7721).The concentration- effect relationship was obvious.IC50 values of EGCG and TCOP were 192.1μ g/ml and 115.0μ g/ml resparately; It was found that TCOP(Po,200mg/kg.d× 7d) could significantly intensify DTH caused by DNFB, and TCOP(Po,200mg/kg.d × 30d) increase the activity of NK cell. It also showed that TCOP(100mg/kg.d,200mg/kg.d,400mg/kg.d× 30d) could improve phagocytosing function of peritoneal macrophage(PMφ ) by 11.35% , 31.97% , 50.8% respectively.TCOP could also activate red cell SOD and reduce the content of MDA of old mice very significantly.A remarkable effect of TCOP on inhibiting or clearing NaNO2 was shown on imitating gastric juice.The antioxidant activity and immunomodulatory enhancing effects of TCOP might be one mechanism of TCOP’s antimutagenicity.

Key words: Tea catechins Oxypolymers Immunity Antitumor