重金属镉和铅胁迫对海洋微藻的毒性效应研究
|
摘要
设置不同浓度的重金属Cd~(2+)(0、0.2、0.4、0.6、0.8和1 mg·L~(-1))和Pb~(2+)(0、0.1、0.2、0. 4、0.8和1.6 mg·L~(-1)胁迫处理,检测米氏凯伦藻(Karenia mikimotoi)的生长生理情况,分析重金属胁迫对海洋微藻生长的毒性效应,探讨超氧化物歧化酶(SOD)和过氧化氢酶(CAT)等对重金属胁迫的缓解作用。研究结果发现,重金属Cd~(2+)和Pb~(2+)对米氏凯伦藻具有较强的毒性,随着重金属浓度的提高,细胞生长受到毒害作用增强;而米氏凯伦藻对重金属Cd~(2+)和Pb~(2+)胁迫具有一定的适应性。重金属Cd~(2+)和Pb~(2+)胁迫导致米氏凯伦藻细胞的叶绿素a、叶绿素b含量下降(1.6 mg·L~(-1) Pb~(2+)胁迫除外),类胡萝卜素含量提高,最大光能转化效率(F_v/F_m)下降,表明重金属胁迫抑制藻的光合作用,影响藻的生长繁殖。丙二醛(MDA)随着重金属Cd~(2+)和Pb~(2+)浓度提高而升高,说明重金属引起藻细胞膜透性增加,藻细胞遭受破坏。SOD活性整体呈现先升高后下降(或与对照持平)的趋势,提示海洋微藻的抗氧化酶系统在低浓度重金属胁迫下产生应激性反应,酶活性增强;而CAT活性上升,也对藻细胞起到保护作用,推测两者共同反应,以缓解藻体遭受的重金属毒害作用。结果可为了解重金属胁迫对海洋微藻的毒性效应提供参考。
Marine microalga Karenia mikimotoi was treated by different concentrations of heavy metals Cd~(2+)(0, 0.2, 0.4, 0.6,0.8 and 1 mg·L~(-1)) and Pb~(2+)(0, 0.1, 0.2, 0.4, 0.8 and 1.6 mg·L~(-1)). Its physiological growth was detected to analyze the toxic effects of heavy metals on the growth of marine microalga. Besides, the effect of superoxide dismutase(SOD) and catalase(CAT) alleviating the toxicity of heavy metals on growth of microalga was discussed. The results showed that heavy metals Cd~(2+) and Pb~(2+) had strong toxicity to the growth of K. mikimotoi. With the increase of heavy metals concentration, the inhibited effect on the cell growth was increased. K. mikimotoi showed certain adaptability to heavy metals Cd~(2+) and Pb~(2+).The stress of Cd~(2+) and Pb~(2+) resulted in the decrease of chlorophyll a and chlorophyll b(except for 1.6 mg·L~(-1) Pb~(2+)), the increase of carotenoids, and the decrease of maximal photochemical efficiency(F_v/F_m), which indicated that heavy metals inhibited the photosynthesis of K. mikimotoi. Malondialdehyde(MDA) increased with the increase of Cd~(~(2+)) and Pb~(2+)concentrations, demonstrating that heavy metals increased the permeability of algae cell membrane and destroyed algal cells.The SOD activity increased first and then decreased(or remained the same level as the control), suggesting that the antioxidant enzyme system of marine microalga was activated under low concentration of heavy metals, hence enzymatic activity increased. Similarly, the increase of CAT activity also implied a protective role on algal cells. It is speculated that the SOD and CAT together can alleviate the toxic effects of heavy metals on algae. The results can provide a reference for understanding the toxic effects of heavy metal stress on marine microalgae.
Marine microalga Karenia mikimotoi was treated by different concentrations of heavy metals Cd~(2+)(0, 0.2, 0.4, 0.6,0.8 and 1 mg·L~(-1)) and Pb~(2+)(0, 0.1, 0.2, 0.4, 0.8 and 1.6 mg·L~(-1)). Its physiological growth was detected to analyze the toxic effects of heavy metals on the growth of marine microalga. Besides, the effect of superoxide dismutase(SOD) and catalase(CAT) alleviating the toxicity of heavy metals on growth of microalga was discussed. The results showed that heavy metals Cd~(2+) and Pb~(2+) had strong toxicity to the growth of K. mikimotoi. With the increase of heavy metals concentration, the inhibited effect on the cell growth was increased. K. mikimotoi showed certain adaptability to heavy metals Cd~(2+) and Pb~(2+).The stress of Cd~(2+) and Pb~(2+) resulted in the decrease of chlorophyll a and chlorophyll b(except for 1.6 mg·L~(-1) Pb~(2+)), the increase of carotenoids, and the decrease of maximal photochemical efficiency(F_v/F_m), which indicated that heavy metals inhibited the photosynthesis of K. mikimotoi. Malondialdehyde(MDA) increased with the increase of Cd~(~(2+)) and Pb~(2+)concentrations, demonstrating that heavy metals increased the permeability of algae cell membrane and destroyed algal cells.The SOD activity increased first and then decreased(or remained the same level as the control), suggesting that the antioxidant enzyme system of marine microalga was activated under low concentration of heavy metals, hence enzymatic activity increased. Similarly, the increase of CAT activity also implied a protective role on algal cells. It is speculated that the SOD and CAT together can alleviate the toxic effects of heavy metals on algae. The results can provide a reference for understanding the toxic effects of heavy metal stress on marine microalgae.
引文
[1]LI R Y,LI R L,CHAI M,et al.Heavy metal contamination and ecological risk in Futian mangrove forest sediment in Shenzhen Bay,South China[J].Marine Pollution Bulletin,2015,101(1):448-456
[2]熊慧,杨丽虹,邓永智.福建省安海湾、围头湾海域表层沉积物重金属含量分布特征及潜在生态风险评价[J].应用海洋学学报,2019,38(1):68-74
[3]FREITAS E C,ROCHA O.Acute and chronic toxicity of chromium and cadmium to the tropical cladoceran Pseudosida ramosa and the implications for ecotoxicological studies[J].Environmental Toxicology,2014,29(2):176-186
[4]YOLOGLU E,OZMEN M.Low concentrations of metal mixture exposures have adverse effects on selected biomarkers of Xenopus laevis tadpoles[J].Aquatic Toxicology,2015,168:19-27
[5]刘易见,颜韦,刘春辰,等.蒽和镉对米氏凯伦藻的生长及叶绿素a、丙二醛含量的影响[J].生态科学,2016,35(4):47-51.
[6]刘桂英,葛坤,宋伦,等.米氏凯伦藻的研究进展[J].海洋科学,2015,39(9):117-122.
[7]郝建军,康宗利.植物生理学实验术[M].北京:化学工业出版社,2006.
[8]李合生.植物生理生化实验原理和技术[M].北京:高等教育出版社,2000.
[9]MORENO-GARRIDO L,PEREZ S,BLASCO J.Toxicity of silver and gold nanoparticles on marine microalgae[J].Marine Environmental Research,2015,111:60-73
[10]徐邦玉,张霞,倪志鑫,等.富营养化对两种海洋微藻吸收铜和镉的影响[J].海洋环境科学,2015,34(5):641-646
[11]杨国远,万凌琳,雷学青,等.重金属铅、铬胁迫对斜生栅藻的生长、光合性能及抗氧化系统的影响[J].环境科学学报,2014,34(6):606-1614.
[12]蔡卓平,段舜山,朱红惠.海洋微藻对重金属镉胁迫的抗氧化应激适应性[J].生态科学,2012,31(5):591-595
[13]于小娣,师玥,刘泳,等.重金属胁迫对两种海洋饵料微藻的急性毒性效应研究[J].中国海洋大学学报,2014,44(2):53-59
[14]杨雨嘉,支崇远,李培林,等.重金属Cd2+和Cu2+对一种曲壳藻生长情况及其抗氧化酶活性的影响[J].生态科学,2015,34(6):75-80.
[15]MANIMARAN K,KARTHIKEYAN P,ASHOKKUMARS,et al.Effect of copper on growth and enzyme activities of marine diatom,Odontella mobiliensis[J].Bulletin of Environmental Contamination and Toxicology,2012,88(1):30-37
[16]蔡卓平,刘伟杰,段舜山.重金属Zn2+胁迫下米氏凯伦藻(Karenia mikimotoi)的生长生理响应研究[J].生态科学,2019,38(2):176-181.
[17]蔡卓平,吴皓,刘伟杰,等.海洋微藻响应重金属复合胁迫的生理生态学机制[J].生态科学,2017,36(3):216-219.
[18]LE T T,ZIMMERMANN S,SURES B.How does the metallothionein induction in bivalves meet the criteria for biomarkers of metal exposure[J].Environental Pollution,2016,212:257-268
[2]熊慧,杨丽虹,邓永智.福建省安海湾、围头湾海域表层沉积物重金属含量分布特征及潜在生态风险评价[J].应用海洋学学报,2019,38(1):68-74
[3]FREITAS E C,ROCHA O.Acute and chronic toxicity of chromium and cadmium to the tropical cladoceran Pseudosida ramosa and the implications for ecotoxicological studies[J].Environmental Toxicology,2014,29(2):176-186
[4]YOLOGLU E,OZMEN M.Low concentrations of metal mixture exposures have adverse effects on selected biomarkers of Xenopus laevis tadpoles[J].Aquatic Toxicology,2015,168:19-27
[5]刘易见,颜韦,刘春辰,等.蒽和镉对米氏凯伦藻的生长及叶绿素a、丙二醛含量的影响[J].生态科学,2016,35(4):47-51.
[6]刘桂英,葛坤,宋伦,等.米氏凯伦藻的研究进展[J].海洋科学,2015,39(9):117-122.
[7]郝建军,康宗利.植物生理学实验术[M].北京:化学工业出版社,2006.
[8]李合生.植物生理生化实验原理和技术[M].北京:高等教育出版社,2000.
[9]MORENO-GARRIDO L,PEREZ S,BLASCO J.Toxicity of silver and gold nanoparticles on marine microalgae[J].Marine Environmental Research,2015,111:60-73
[10]徐邦玉,张霞,倪志鑫,等.富营养化对两种海洋微藻吸收铜和镉的影响[J].海洋环境科学,2015,34(5):641-646
[11]杨国远,万凌琳,雷学青,等.重金属铅、铬胁迫对斜生栅藻的生长、光合性能及抗氧化系统的影响[J].环境科学学报,2014,34(6):606-1614.
[12]蔡卓平,段舜山,朱红惠.海洋微藻对重金属镉胁迫的抗氧化应激适应性[J].生态科学,2012,31(5):591-595
[13]于小娣,师玥,刘泳,等.重金属胁迫对两种海洋饵料微藻的急性毒性效应研究[J].中国海洋大学学报,2014,44(2):53-59
[14]杨雨嘉,支崇远,李培林,等.重金属Cd2+和Cu2+对一种曲壳藻生长情况及其抗氧化酶活性的影响[J].生态科学,2015,34(6):75-80.
[15]MANIMARAN K,KARTHIKEYAN P,ASHOKKUMARS,et al.Effect of copper on growth and enzyme activities of marine diatom,Odontella mobiliensis[J].Bulletin of Environmental Contamination and Toxicology,2012,88(1):30-37
[16]蔡卓平,刘伟杰,段舜山.重金属Zn2+胁迫下米氏凯伦藻(Karenia mikimotoi)的生长生理响应研究[J].生态科学,2019,38(2):176-181.
[17]蔡卓平,吴皓,刘伟杰,等.海洋微藻响应重金属复合胁迫的生理生态学机制[J].生态科学,2017,36(3):216-219.
[18]LE T T,ZIMMERMANN S,SURES B.How does the metallothionein induction in bivalves meet the criteria for biomarkers of metal exposure[J].Environental Pollution,2016,212:257-268