Cr~(3+)胁迫对小球藻生理生化特性的影响

水体重金属污染较难处理,且会对水生物造成严重的影响。为探讨水体中重金属对藻类的毒性影响,以普通小球藻(Chlorella vulgaris)和铬(Cr~(3+))为材料,研究不同浓度Cr~(3+)对普通小球藻生理、生化特性的影响,检测不同浓度的Cr~(3+)对小球藻的毒性效应。结果表明,小球藻的最优生长温度为31℃。此条件下,Cr~(3+)浓度为3 mg·L~(-1)时,小球藻的生物量最大。Cr~(3+)的浓度低于3 mg·L~(-1)时,Cr~(3+)能促进小球藻的生长,且藻细胞中光合色素、蛋白质、可溶性糖、丙二醛(MDA)的含量及超氧化物歧化酶(SOD)的活性也逐渐增加。当各胁迫组的Cr~(3+)浓度超过3 mg·L~(-1)时,随着Cr~(3+)浓度的提高,C.vulgaris的生长受到明显的抑制,藻细胞的光合色素、蛋白质和可溶性糖含量呈现逐渐下降的趋势,而MDA含量持续增加,SOD和脯氨酸则表现出先持续增高后降低(Cr~(3+)浓度为7 mg·L~(-1)时)的趋势。证明不同浓度的Cr~(3+)对小球藻的生理生化特性有不同程度的毒性效应。

The Effect of Cr3+ Stress on Physiological and Biochemical Characteristics of Chlorella vulgaris

Heavy mental pollution of water body is difficult to treat,and can cause serious effects on aquatic organisms.In order to reveal the toxic effects of heavy metal,Chlorella vulgaris was exposed to different concentrations of Cr3+.The physiological and biochemical characteristics were determined.The results showed that the optimal growth temperature of C.Vulgaris was 31 ℃.Under this condition,the maximum values of biomass,photosynthetic pigment,protein and soluble sugar contents in algae cells were detected at the Cr3+ concentration of 3 mg · L-1.On the contrary,the growth of C vulgaris was obviously inhibited with the Cr3+ concentration higher than 3mg· L-1.The increase in malondialdehyde (MDA) content and decrease in photosynthetic pigments,proteins,soluble sugar,the activity of superoxide dismutase (SOD) and proline contents were shown at a high Cr3+ concentration of 7 mg· L-1.It is indicated that Cr3+ exhibited toxic effects on physiological and biochemical characteristics of C.vulgaris in a concentration-depended manner.