电子束辐射对铜绿微囊藻生长过程的影响研究

Effects of Electron Beam Irradiation on the Growth Process of Microcystis aeruginosa

在辐射剂量分别为1、2、3、4、5kGy的情况下,研究电子束辐射对铜绿微囊藻生长过程及繁殖规律的影响。结果表明：1kGy的辐射剂量能减缓铜绿微囊藻的正常生长,2-5kGy有明显的灭活效果。实验结束时,对照组和1kGy辐射组光密度上升1.082和0.407;2-5kGy下降分别为0.533、0.731、0.889和0.946。铜绿微囊藻叶绿素a含量的变化规律与光密度变化规律相似。电子束辐射降低藻液的pH值,铜绿微囊藻通过光合作用和生理调节使pH值升高并逐渐稳定下来。电子束辐射使藻液的电导率增加,并通过对藻细胞的破坏使电导率保持增加。电子束辐射使铜绿微囊藻的细胞结构发生明显变化。电子束辐射首先减少细胞外的糖类物质,进而破坏类囊体结构,使光合作用受阻。

Under the electron beam irradiation with irradiation doses of 0, 1, 2, 3, 4, and 5 kGy, the effects of the irradiation on the growth process and reproductive pattern of Microcystis aeruginosa were studied respectively. The results indicate that the growing speed of Microcystis aeruginosa slows down by irradiation of 1 kGy, while each irradiation dose of 2~5 kGy causes an apparent effect of inactivation. Under the irradiation doses of 0 and 1 kGy, at the end of the irradiation the light densities of the Microcystis aeruginosa liquid increase 1.082 and 0.407, respectively, while under irradiation doses of 2~5 kGy, the light densities decrease 0.533, 0.731, 0.889 and 0.946, respectively. The change tendency of chlorophyll a content in Microcystis aeruginosa is similar to that of the light density. Electron beam irradiation makes the pH of Microcystis aeruginosa liquid decrease, and via photosynthesis and physiologic adjustment of the Microcystis aeruginosa, the pH grows up gradually and becomes stable. The conductivity of Microcystis aeruginosa liquid increases by irradiation and keeps increasing as a result of the destruction of the cell. The TEM photographs show that the cellularity of Microcystis aeruginosa is obviously changed by electron beam irradiation; the electron beam radiation firstly reduces the extracellular carbohydrates and then destroys the structure of thylakoid, which obstructs photosynthesis.