Based on the B3LYP methods of density functional theory and the MP2 methods of perturbation theory

the chiral transformation mechanism of the Val monomer molecule

the catalytic effect of water molecules and hydroxyl radicals on the hydrogen transfer reaction were studied. The reaction channel analysis showed that there were four channels a

b

c and d in the Val chiral enantiomer transformation reaction. Channels a and c

the chiral shift was achieved by the H of chiral carbon transferring to the other side from the bridge of Amino N and Carbonyl O respectively. Channel b

the chiral shift was achieved by the H of chiral carbon transferring to the other side from the bridge of Amino N and Carbonyl O in turn. Channel d

the chiral shift was achieved by the H of chiral carbon transferring to the other side from the bridge of Hydroxyl O. From the calculation of potential energy surface

channel a was the optimal reaction channel

the highest energy barrier is 257.6 kJ·mol

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. One water molecule

two water molecules chain and the chain of one water molecule and Hydroxyl radical showed better catalytic effect on the H shift reaction

which decreased the high energy barrier in channel a to 160.3

124.4 and 104.0 kJ·mol

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 accordingly. The result revealed that optical isomer of valine molecule in living body was formulized mainly under the joint action of water molecule and hydroxyl radical.