水环境中海水小球藻和塔胞藻对苯并[k]荧蒽致毒胁迫的响应

Responses of Chlorella vulgaris and Pyramidomonas delicatula to the Toxic Effects of Benzo [k] Fluoranthene in Water Environment

以2种海洋微藻的生长量、酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、过氧化氢酶(CAT)和丙二醛(MDA)为检测指标,研究海水小球藻(Chlorella vulgaris)和塔胞藻(Pyramidomonas delicatula)对苯并[k]荧蒽的致毒胁迫的生理响应,揭示出多环芳烃化合物对水环境污染的重要性。结果显示,苯并[k]荧蒽对2种海洋微藻生长都存在抑制作用,海水小球藻的抑制率最高达62%,并存在剂量效应;适当浓度的苯并[k]荧蒽对塔胞藻生长有短时刺激作用,高浓度的苯并[k]荧蒽对塔胞藻有强烈的抑制作用,其最大抑制率达到89%。添加固定浓度(9μg/L)苯并[k]荧蒽处理2种微藻,海水小球藻体内ACP活性至72 h达最大值,与对照组相比,增加32%,塔胞藻48 h达到最大,升高105%;AKP活性变化趋势与ACP活性基本一致;海水小球藻CAT活性至72 h达到最大值,是对照组的2.3倍,塔胞藻CAT活性至48 h即达最高,为对照组的2.5倍;2种微藻MDA含量随着苯并[k]荧蒽暴露时间的增加而升高,与对照组相比,海水小球藻和塔胞藻在72 h MDA含量分别升高73%、81%;苯并[k]荧蒽对海洋微藻的致毒效应存在种属差异,对塔胞藻的致毒效应大于海水小球藻。

In this paper,the growth of two kinds of marine microalgae,acid phosphatase(ACP),alkaline phosphatase(AKP),catalase(CAT)and malondialdehyde(MDA)were used as indicators to study the responses of Chlorella vulgaris and Pyramidomonas delicatula to the toxic effects of benzo[k]fluoranthene in water environment and to reveal the importance of polycyclicaromatic-hydrocarbons for water pollution.The results showed that benzo[k]fluoranthene had inhibitory effect on the growth of two kinds of marine microalgae,and the inhibition rate of benzofluoranthene to C.vulgaris was up to 62%,and there was dose effect.The proper concentration of benzo[k]fluoranthene had a short time stimulating effect on P.delicatula,while high concentration of benzo[k]fluoranthenes had a strong inhibitory effect on P.delicatula,and its maximum inhibition rate was 89%.Two kinds of microalgae were prepared by adding fixed concentration(9μg/L)of benzo[k]fluoranthene,the results showed the ACP of C.vulgaris reached the maximum at 72 h,which was 32%higher than that of the control group,while the ACP activity of P.delicatula reached the maximum at 48 h and increased by 105%.The trend of AKP activity was consistent with that of ACP.The CAT activity in C.vulgaris reached the maximum at 72 h,which was 2.3 times higher than that in the control group,and the activity of CAT was up to 48 h,which was 2.5 times of that of the control group.The content of MDA in two kinds of microalgae increased with the exposure time of benzo[k]fluoranthene.Compared with the control group,the contents of MDA in C.vulgaris and P.delicatula were increased by 73%and 81%at 72 h respectively.There was a difference in the toxic effects of benzo[k]fluoranthene on marine microalgae,and the toxic effects on P.delicatul were serious on C.vulgaris.