应用DSI试验观察互隔交链孢霉提取物的诱变性

应用DSI试验对食管癌高发区河南林县粮食中分离的互隔交链孢霉的提取物进行诱变性研究。在五个数量级浓度中,互隔交链孢霉提取物均能明显地抑制DNA的合成。其抑制率为51.2%～62.8%,有明显的剂量相关性。与对照组相比有极显著差异(P<0.01)。追踪观察表明,经10~-3mg/ml浓度的提取物作用后,靶细胞DNA合成速度在与提取物脱离接触后的0.5h内呈进行性下降,以后才逐渐回升,在0.5h处形成一个DNA合成的谷值。故可认为,互隔交链孢霉提取物中含有损伤性DNA合成抑制剂,但损伤修复较快。结果表明,互隔交链孢霉提取物中含有诱变性物质。

The experimental observation of the mutagenicity of the extract of Alternaria alternata with DSI test

By means of DNA Synthesis Inhibition Test (DSI), the mutagenicity of the extract of Alternaria alternata isolated from the crops of Linxian County, a highrisk area of esophageal cancer, was studied. The experiment showed that the extractwith the concentrotions of 10~(-5) to 10~(-1)mg/ml could induce inhibition of DNA synthesisin human amnion cells in vitro. The rate of inhibition was 51.2% to 62.8.%; therate was related to the concentration of the extract. The DNA synnthesis rate byextract was significantly different from the rate by solvent control (P<0.01).Experiment demonstrated that the rate of DNA synthesis of the target cells treatedwith the extract of 10~(-3)mg/ml decreased in time after the removal of the med-ium, which contained the agent, and the valley was found in the curve of DNAsynthesis.The extract of Alternaria alternata was regard as DNA-damaging agentand mutagen. Its mutagenicity may have something to do with electrophilic agent.