氧化铁纳米颗粒固定化溶藻菌的除藻作用

为了探讨氧化铁纳米颗粒固定化溶藻菌后对铜绿微囊藻的溶藻作用和降解微囊藻毒素LR(MC-LR)的作用,从太湖水体中分离获得一株属于芽孢杆菌属的溶藻菌,将其与氧化铁纳米颗粒固定化后,以普通Fe2O3作为实验对照,测定其溶藻作用和降解MC-LR作用.以激光粒度仪测定氧化铁纳米颗粒与溶藻菌两者单独和同时存在时的粒径大小及粒径分布,以获得氧化铁纳米颗粒固定化溶藻菌的证据.分析结果表明:在太湖水体中分离获得的一株芽孢杆菌具有较强的溶藻和降解MC-LR的作用,作用24 h后的溶藻率和MC-LR降解率分别达到44.3%和20.5%.同时加入氧化铁纳米颗粒后,溶藻率达到53.0%,MC-LR的降解率达到33.0%.激光粒度仪检测发现,氧化铁纳米颗粒与细菌混合后的颗粒物的平均直径增加到氧化铁纳米颗粒的12.3倍,同时氧化铁纳米颗粒和细菌单独存在时的粒径分布峰消失.氧化铁纳米颗粒是一种具有良好性能的生物固定化材料,可能通过其特有的途径有效地固定化溶藻菌,并增强溶藻菌的溶藻和降解藻毒素作用.

Algae-lyric effect of algicadal bacteria immobilized on Fe2O3 nanoparticles

To investigate the performance and ability of Fe203nanoparticles for algicidal bacteria immobilization and to evaluate the algae-lytic effect and microcystin-LR degradation of algicadal bacte- ria immobilized on Fe2O3 nanoparticles, a kind of algicidal bacterium, which was isolated from Taihu Lake and identified as Bacillus, were immobilized on Fe2O3 nanoparticles. Then aglae-lysing rates and microcystin-LR degradation rates of the bacteria immobilized on Fe2O3 nanoparticles were determined at 6,12 and 24 h. The laser particle size analysator was used to measure particle diameter distribution and their mean diameter. The bacteria isolated from Taihu Lake were proven to have significant effect of algicidal activity and degradation of microcystin-LR. The results show that the 24 h aglae-lysing rate and the microcystin-LR degradation rate of the bacteria with 10^4/mL of microcytis aeruginosa are 44.3% and 20. 5%, respectively. When immobilized on Fe2O3 nanoparficles, the 24 h aglae-lysing rate and the microcystin-LR degradation rate of the bacteria are 53.0% and 33.0%, respectively. The mean diameter of the particles after bacteria immobilization is 12. 3 times of the Fe2O3 particles. The results suggest that Fe2O3 nanoparticles, as a kind of artificial medium, could effectively immobilize algicidal bacteria, and significantly strengthen the algae-lyric effect of bacteria to microcytis aeruginosa and degradation of microcystin-LR.