无机氮和有机氮对铜绿微囊藻生长和产毒影响的比较

Comparison of inorganic nitrogen and organic nitrogen on the growth and microcystin production of Microcystis aeruginosa

以氯化铵和丙氨酸作为氮源,通过测定铜绿微囊藻细胞生物量、胞内藻毒素含量、基质利用率等变化情况探究并比较两种含氮化合物对铜绿微囊藻生长和产毒的影响.结果表明铵氮低浓度(<10 mg·L-1)促进铜绿微囊藻生长,而高浓度(>20 mg·L-1)具有抑制作用;不同浓度的丙氨酸对铜绿微囊藻的生长均具有促进作用,最适生长浓度为20 mg·L-1.铵态氮对藻毒素产生的促进作用不明显,丙氨酸则较大的促进了微囊藻产毒,是同时期对照组的6倍.

In this study,two nitrogen-bearing compounds,ammonium chloride and alanine,were compared for their effects on the growth and toxin production of Microcystis aeruginosa. Cell abundance,intracellular microcystin concentration,and the utilization rate of substrate were chosen as the indicators. Results indicated that low ammonium concentration( < 10 mg·L- 1) promoted the growth of Microcystis aeruginosa,while high ammonium level( > 20 mg·L- 1) inhibited. Alanine of all the tested concentrations could enhance Microcystis aeruginosa growth,and the optimal level was found to be 20 mg·L- 1. The enhancing effect of ammonium-nitrogen on microcystin production was not significant,but alanine was much more effective,with the corresponding microcystin level 6 times that of the control sample.