单壁碳纳米管对莱茵衣藻光合产氢的影响

Effects of single-walled carbon nanotubes on photosynthetic hydrogen production in Chlamydomonas reinhardtii

[目的]研究单链DNA包裹前、后的单壁碳纳米管(SWCNT)对莱茵衣藻光合作用和光合产氢的影响,为利用藻类高效产氢提供新思路。[方法]对单壁碳纳米管进行单链DNA修饰,利用光谱学等方法表征其理化性质。将单链DNA包裹前、后的单壁碳纳米管引入莱茵衣藻培养体系共孵育,观察单壁碳纳米管在衣藻细胞中的分布及其对衣藻光合作用和光合产氢的影响。[结果]单链DNA修饰可以增加单壁碳纳米管在溶液中的稳定性,减少纳米管团聚引起的衣藻细胞聚集。单链DNA包裹前、后的单壁碳纳米管对莱茵衣藻生长仅有轻微抑制。在缺硫条件下,与对照相比,2种形态单壁碳纳米管(ss DNA/SWCNT、SWCNT)均造成衣藻PSⅡ活性下降,呼吸速率显著高于光合速率,从而诱导衣藻细胞更快进入缺氧状态。2种形态单壁碳纳米管均可促进莱茵衣藻光合产氢,但未经包裹的单壁碳纳米管效果更加明显,可提高产氢量5倍以上。[结论]单链DNA包裹可提高单壁碳纳米管在溶液中的稳定性和分散性。单壁碳纳米管可通过影响PSⅡ活性和增强呼吸代谢的方式促进莱茵衣藻光合产氢。

[Objectives] In order to provide new strategy for efficient hydrogen production in Chlamydomonas reinhardtii ,the effects of single-walled carbon nanotubes(SWCNT)on the photosynthesis and photosynthetic hydrogen production were studied.[Methods] SWCNT were modified with single strand DNA(ssDNA),and the physical-chemical properties of ssDNA/SWCNT were characterized. SWCNT and ssDNA/SWCNT were co-cultivated with C.reinhardtii ,respectively,and the effects of the two types of SWCNT on the photosynthesis and H 2 production were investigated.[Results] ssDNA could enhance the dispersion of SWCNT in solution and reduced C.reinhardtii cell aggregation,which was more significant under raw SWCNT treatment. Both of ssDNA/SWCNT and SWCNT slightly inhibited the growth of C.reinhardtii . In S-deprivation condition,two types of SWCNT could inhibit PSⅡ activity,and significantly promote the respiration rate. As a result,SWCNT treatments increased the photosynthetic H 2 production in C.reinhardtii ,and SWCNT could further promote H 2 production by more than 5 times than the control.[Conclusions] ssDNA modification can improve the stability and dispersion of SWCNT in solution,and SWCNT could promote photosynthetic hydrogen production by inhibiting PSⅡ activity and enhancing respiratory metabolism in C.reinhardtii .