不同浓度维生素C对DNA紫外损伤的影响

Effects of Different Levels of Vitamin C on UV Radiation-Induced DNA Damage

分别检测了DNA与不同浓度维生素C的混合物经10和30 min紫外辐射的拉曼光谱,紫外线的辐 射照度为18．68W·m-2。实验表明,维生素C对DNA损伤的影响与其浓度密切相关。低于0．35 mmol·L-1 的维生素C对紫外线诱发的DNA损伤具有明显的保护作用,且保护效果随着其浓度的增大越来越好,0．35 mmol·L-1时保护效果最佳。当维生素C的浓度高于0．35 mmol·L-1时,在10 min的紫外辐射中,维生素C 不仅没有保护DNA,反而促进了DNA的损伤,DNA被损伤的程度随着维生素C浓度的增加而增加;但在 30 min的紫外辐射中,相对于不加VC的紫外辐射,维生素C对DNA仍起保护作用。

The Raman spectra of DNA in different levels of vitamin C with 10 rain ultraviolet radiation and 30 min ultraviolet radiation were reported. The intensity of ultraviolet radiation was 18.68 W·m^-2. The experimental results proved that vitamin C can reduce DNA damage solely, but the effects are related to the concentration of vitamin C. When the concentration of vitamin C was lower than 0.35 mmol·L^- 1, DNA was protected better with the rising of vitamin C concentration during ultraviolet radiation. DNA was protected best when vitamin C was 0.35 mmol·L^- 1. When vitamin C concentration was higher than 0.35 mmol·L^- 1, vitamin C accelerated DNA damage with 10 min ultraviolet radiation. But DNA was also protected with 30 min ultraviolet radiation as vitamin C was 0.35- 0.65 mmol·L^-1. However, DNA was only protected slightly at high concentration of vitamin C.