对苯二酚抑制铜绿微囊藻生长下藻毒素的产生与释放

选用对苯二酚,根据其抑藻的剂量效应关系,研究了铜绿微囊藻在不同抑制条件下,即投加剂量为EC20、EC50、EC70、EC90、EC99时,藻毒素Microcystin-LR(MCLR)的产生与释放,并通过测定总有机碳和三维荧光光谱,研究了细胞内有机物的释放状况.结果表明,EC20作用下,藻毒素的产生受到抑制,总MCLR约为对照样的72.4%~83.0%;在EC50~EC99作用下,藻细胞受到刺激,毒素产量明显增加,总MCLR可升至对照样的1.77~3.13倍,且在EC70~EC99作用下,胞内毒素大部分释放于胞外.细胞释放的其它有机物主要是类腐殖酸和类富里酸,但并不稳定,6 d后,发生了明显的降解与转化.

Generation and Release of Microcystin-LR by Microcystis aeruginosa Under Hydroquinone Inhibition

The generation and release of algal toxin Microcystin-LR (MCLR), as well as the intracellular organic chemicals were studied during the inhibition processes of Microcystis aeruginosa using hydroquinone as the inhibitor. According to the dose-effect relationship, the corresponding dosages of EC₂₀, EC₅₀, EC₇₀, EC₉₀, EC₉₉ were added to the algae suspension. The TOC was determined by the total organic carbon analyzer, and the three-dimensional fluorescence spectrum was obtained by the fluorescence spectrophotometer. The results showed that the generation of MCLR was inhibited at EC₂₀ and the total MCLR was 72.4%-83.0% of the control samples. Whereas the cells were stimulated to produce higher amount of MCLR, and the total MCLR was 1.77-3.13 times as high as that of the control samples at EC₅₀-EC₉₉. The intracellular MCLR was largely released to the water at EC₇₀-EC₉₉. The release of other intracellular organic chemicals mainly referred to humic-like and fulvic-like substances, which were unstable and had an obvious degradation and transformation after 6 days of cultivation.