纳米二氧化钛胁迫对普生轮藻的毒性效应

纳米材料独特的理化性质使其得到了广泛的应用,但其可能带来的生物安全性问题也引起了广泛关注.实验研究了胁迫浓度梯度为0、0.01、0.10、1.0、10、100mg.L-1的纳米二氧化钛(nTiO2)悬浮液单一处理普生轮藻(CharavulgarisL.)的毒性效应,在胁迫24h、48h、72h、96h后分别测定其叶绿素a含量、脂质过氧化物丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性和过氧化氢酶(CAT)活性.结果表明,随着胁迫浓度的增加和时间的延长,叶绿素a含量、SOD和CAT活性总体呈下降趋势,而MDA含量呈递增趋势,高浓度剂量组与对照组比较差异极显著,酶的活性降幅也较大,说明急性nTiO2暴露对普生轮藻具有毒性作用,且表现出剂量效应.

Toxic effects of nanoparticle TiO2 stress on Chara vulgaris L.

Nanomaterials have been widely used due to their unique physical and chemical properties. However, their potential bio-security issues aroused widespread concern. The experiment investigated the effects of nanoparticle titanium dioxide (nTiO₂) suspensions to Chara vulgaris L. The contents of chlorophyll a, malonyldialdehyde (MDA), the activities of superoxide dismutase (SOD) and catalase (CAT) were measured in different concentrations of nTiO₂ suspensions of 0, 0.01, 0.1, 1.0, 10, 100 mg·L^-1. The results indicated that, as the stress of nTiO₂ increased and time evolved, the contents of chlorophyll a, the activities of SOD and CAT showed a downward trend. By contrast, the MDA had an increasing trend. With the dose stress increasing, the differences were significant and the enzyme activity declined sharply compared with control. In summary, the data suggested that the exposure of nTiO₂ had toxicity on C. vulgaris L. in a dose-dependent manner.