关键词: DNA 损伤, 日本三角涡虫, Pb2 + 、Cd2 + 胁迫, 绿豆浸出液, 损伤修复

Abstract: Abstract: We used technology of Ultraviolet Spectrophotometry and Agarose Gel Electrophoresis to analyze DNA damage under Pb2 + and Cd2 + stress in Dugesia japonica’somatic cell，and DNA damage repair by lixivium of green beans． The concentration of Pb2 + and Cd2 + were respectively120 mg /L ( Pb( NO3)2) and 1 mg /L ( CdCl2) ．We also added control groups with lixivium of green beans to repair the damaged DNA． Planaria were exposed to 24 hours and extracted using method of Proteinase K ． Though the analysis of experimental data． The results show that Lead and cadmium can induce DNA-DNA cross-linking and cut the DNA into smaller snippet． It had a better effect with the lixivium of green beans for damage repair caused by Cd2 + stress． For DNA damage caused by Pb2 + stress，it also had a better effect if we added the green beans lixivium at the same time with Pb( NO3)2 . The reason is probable because the lixivium can precipitate Pb2 + ． But in control group which we added the lixivium afterdamage，there had not repairable effect in DNA damage．

Key words:  DNA damnification, Dugesia japonica, Pb2 + 、Cd2 + stress, mung bean lixivium, damage repair