多种藻类对As(Ⅲ)的耐受性及吸附研究

Study on Arsenic Tolerance and Biosorption of Various Microalgae

[目的]筛选到在自然条件下能有效去除水体中砷污染的微藻。[方法]以4种微型绿藻(小球藻Chlorella sp.(zfsaia)、Chlorellaminata、Chlorella vulgaris和羊角月牙藻Selenastrum capricormulum)为材料,选取6个不同浓度的As(III)(0.5、1.0、2.0、5.0、10.0、20.0mg/L)进行培养处理,以生物量、叶绿素a含量等生理指标研究这4种藻类对砷的耐受性及其吸附情况。[结果]小球藻Chlorella sp.(zf-saia)对砷的毒害有敏感性,当砷浓度超过10 mg/L时,其生长受到抑制,EC50值为17.32 mg/L;当砷浓度在0～20 mg/L范围内,羊角月牙藻Selenastrum capricormulum、小球藻Chlorella minata和Chlorella vulgaris生长不受影响,对砷具有较高的耐受性,24 h后,它们对砷的去除率分别达77.02%、72.18%和81.36%。[结论]该研究表明藻类在治理含砷废水和作为砷污染废水的指示性植物等方面具有良好的应用前景。

[ Objective ] This study aimed to select microalgae species which are capable to effectively remove arsenic contamination from water under natural conditions. [ Method] Four microalgae species [ Chlorella sp. （zfsaia）, Chlorella minata, Chlorella vulgaris and Selenastrum capricormulum] were used as experimental materials and cultured with six different concentrations of As （III） （0.5, 1.0, 2.0, 5.0, 10.0, 20.0 mg/L）. Biomass, chlorophyll a content and other physiological indicators were determined to investigate the arsenic tolerance and biosorption of four microalgae species. [ Result] Chlorella sp. （zfsaia） is sensitive to arsenic toxicity, its growth was inhibited when arsenic concentratinn exceeded 10 mg/L, with a EC50 of 17.32 mg/L; when the arsenic concentration was 0 -20 mg/L, growth of Selenastrum capricormulum, Chlorella minata and Chlorella vulgaris was not affected, which showed relatively high tolerance to arsenic, with arsenic removal rates of 77.02% , 72.18% and 81.36 respectively after 24 h. [ Conclusion] This study indicates that microalgae have good application prospects for processing arsenic wastewater and being indicator plants of arsenic wastewater.