摘要
This research aimed to evaluate the alga Scenedesmus obliquus toxicity induced by textiledyeing effluents(TDE).The toxicity indicator of TDE in alga at the physiological(algal growyth),biochemical(chlorophyll-a(Chl-a)synthesis and superoxide dismutase(SOD)activity)and structural(cell membrane integrity)level were investigated.Then we further study the relationship among toxicity indicators at physiological and biochemical level,and supplemented by research on algal biomacromolecules.According to the analysis of various endpoints of the alga,the general sensitivity sequence of toxicity endpoints of Scenedesmus obliquus was:SOD activity>Chl-a synthesis>algal growth.The stimulation rate of SOD activity increased from day 3(57.25%~83.02%)to day 6(57.25%~103.81%),and then decreased on day 15(-4.23%^-32.96%),which indicated that the antioxidant balance system of the algal cells was destroyed.The rate of Chl-a synthesis inhibition increased gradually,reaching19.70%~79.39%on day 15,while the rate of growth inhibition increased from day 3(-12.90%~10.16%)to day 15(-21.27%~72.46%).Moreover,the algal growth inhibition rate was positively correlated with the inhibition rate of SOD activity or Chl-a synthesis,with the correlation coefficients were 0.6713 and 0.5217,respectively.Algal cells would be stimulating to produce excessive reactive oxygen species,which would cause peroxidation in the cells,thereby destroying chloroplasts,inhibiting chlorophyll synthesis and reducing photosynthesis.With increasing exposure time,irreversible damage to algae can lead to death.This study is expected to enhance our understanding of the ecological risks through algal tests caused by TDE.
基金
supported by the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Z032)
the Natural Science Foundation of China(No.21577027)
the 2017 Central Special Fund for Soil
Preliminary Study on Harmless Treatment and Comprehensive Utilization of Tailings in Dabao Mountain(No.18HK0108)
