Research Of Effects Of Nucleosides,Nitrogen Bases And Ribose On The Formation Of PhIP And MeIQx

In this study, we chose two main heterocyclic amines PhIP and MelQx as the research object, the establishment of creatinine and phenylalanine as the precursors to generate PhIP in simulation system and of creatinine, glycine and glucose as the precursors to generate MelQx simulation system .The effect of nucleosides, nitrogen bases and ribose on the formation of PhIP and MelQx were also investigated in detail.The results showed that the amount of PhIP was increased with the increase of the amount of creatinine and phenylalanine in the simulated system when the ratio of precursor was fixed. With the increase of creatinine, glycine and glucose in the simulated system, the amount of MelQx increased first and then decreased.The effect of nucleic acids on the formation of heterocyclic amines was studied. The results showed that adenine promoted rate was 29.78%?124.47%, the rate of hypoxanthine was 39.13%?59.52%, the rate of xanthine was 25.71% ?53.76%, the rate of thymine was 9.19%?27.02% ,the rate of uracil was 8.29% ?35.46% , the rate of cytosine was 6.51%?29.19%,when the base addition levels was 0.?0.25 mmol .The ability of purine to promote PhIP was more than that of pyrimidine. The amount of MelQx was not significantly affected by the addition of 0.01?0.25 mmol of the base in the simulated system of MelQx (P <0.05). D-ribose and 2-deoxy-D-ribose were added into the system respectively. With the increase of D-ribose content, the amount of PhIP increased first and then decreased, and the amount of MeIQx contiinued to decrease. With the addition of 2-deoxy-D-ribose, the amount of PhIP and MeIQx decreased. In the PhIP simulation system. 0.01?0.25 mmol of 4 nucleosides were added respectively. Among them, adenosine,inosine and uridine had a positive effect on PhIP formation, while cytidine had no significant effect on PhIP formation.Based on the results of nucleic acid-promoted PhIP generation, we further studied whether nucleic acids are involved in their production as precursors, and studied the effects of nucleic acids on the formation of PhIPs, including creatinine, bases as precursors and phenylalanine and bases as precursors .The results show that the base does not react directly with creatinine or phenylalanine to produce PhIP.