산화성 스트레스에 의한 DNA의 회복에 미치는 녹차씨 추출물의 항산화제 효과

Abstract

The effects of green seed extracts including extracts of promegranate seed, grape seed, elm tree bark and royal azaleas as antioxidants or prooxidants were examined. The results show that the green seed extracts are only shown as antioxidants, but the others are shown as a prooxidants against DNA damage and Escherichia coli cells under oxidative stress. The green seed extracts were analyzed by HPLC and then the kamempfrol was found. However, it was not found in green tea extracts that contained the epigallocatechin, catechin, epicatechin, epigallocatechin gallate, gallocatechin gallate, epicatechin gallate and catechin gallate. Therefore, I suggested that kamempfrol may be strong candidate for antioxidants. The green seed extracts strongly inhibited paraquat - induced DNA single strand breakage of pUC 19 plasmid and calf thymus DNAs. Forthermore, the damaged DNAs were repaired by treatment of green seed extracts. In addition, the green seed extracts also inhibited the damages of E. coli cells against paraquat induced-oxidative stress. The strand breaks of DNA were stimulated also with α-tocopherol and catechin, but not with BHT and green seed extracts in the presence of paraquat. These results suggest that the green extracts act as antioxidants, but the other applied samples has a prooxidative effect DNA damage and cell survival against oxidative stress.