Pb2 胁迫对蛋白核小球藻叶绿素荧光强度及亚显微结构的影响

实验研究了蛋白核小球藻叶绿素荧光强度及亚显微结构受不同浓度Pb2+的影响。实验结果表明:随暴露时间的进行0、1 mg/L Pb(NO3)2处理组蛋白核小球藻的叶绿素荧光强度是逐渐升高的;而5、10、50、80 mg/L处理组的藻叶绿素荧光强度逐渐降低;且Pb2+浓度越大其荧光强度的下降趋势越明显。经Pb2+处理的蛋白核小球藻细胞易破裂且多变形,细胞壁和原生质体结合疏松,细胞超微结构中的细胞器如叶绿体、线粒体、蛋白核、淀粉与液泡等受到了Pb2+毒性影响,导致其细胞内的各个系统受到明显影响,进而影响到藻细胞的荧光特性。

Effects of Pb2 stress on chlorophyll fluorescence intensity and ultrastructure of Chlorella pyrenoidosa

Stress effects of heavy metal lead (Pb₂ ) with different concentrations on the chlorophyll fluorescence intensity and ultrastructure of Chlorella pyrenoidosa were studied in the present work. When induced by Pb₂ solution of 0 and 1 mg/L, the fluorescence intensity of C. pyrenoidosa increased gradually with the exposure time, which was similar to the control group. While the intensity decreased with the exposure time when exposed to high concentration of Pb₂ solution (i.e., 5, 10, 50, 80 mg/L ), and an obvious concentration fluorescence intensity response relationship was obtained. Rupture and deformation of C. pyrenoidosa cells, as well as the structure loose between cell wall and protoplast were observed after the exposure of Pb₂ solution. The poisoning of organelles (chloroplasts, mitochondria and vacuoles, etc.) of cell ultrastructure exposed to Pb₂ solution could be the main reason of the fluorescence intensity change of algal cells.