ABSTRACT
The Raman spectra of DNA in different levels of vitamin C with 10 min ultraviolet radiation and 30 min ultraviolet radiation were reported. The intensity of ultraviolet radiation was 18.68 W x 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 x 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 x L(-1). When vitamin C concentration was higher than 0.35 mmol x 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 x L(-1). However, DNA was only protected slightly at high concentration of vitamin C.
Subject(s)
Ascorbic Acid/chemistry , DNA/chemistry , Ultraviolet Rays , Animals , Cattle , DNA Damage , Spectrum Analysis, RamanABSTRACT
The Raman spectra of calf thymus DNA in aqueous solution and at 9, 20 and 40 min after ultraviolet radiation were reported. The experimental results proved that though the ultraviolet radiation time was not long, it had a serious influence on the DNA. Only through 9 min of ultraviolet radiation, the peak of 1094 cm(-1) changed into a few weaker peaks, and it was proved that the molecular conformation was changed and the hydrogen bonds were damaged. Some kinds of nucleotides came into being because of the damage to the DNA molecular. Ultraviolet radiation also had influence on adenine, guanine, cytosine and thymine. Among them the purine and pyrimidine were badly damaged. At the same time, our experiment proved that DNA in aqueous solution possesses both A-type structure and B-type structure.