A Theoretical Study of the Molecular Coupled Structures of Aristolochic Acids and Humic Acid, Potential Environmental Contaminants.

An understanding of the fate of organic compounds originating from plants in soil is crucial for determining their persistence and concentrations in the environment. Aristolochic acids are believed to be the causal agents that induce Balkan endemic nephropathy by food contamination through soil adsorption of humic acids, major components of soil. Aristolochic acids are active chemicals in Aristolochia plant species found in endemic villages. In this article, molecular structure interactions between 18 structures of aristolochic acids with an inserted humic acid structure were studied. These structures were optimized in vacuo and by periodic box simulation with water solvate using the computational molecular mechanics MM+ method with HyperChem software. The QSPR models were used for correlation of the relationship between the hydrophobicity values of 18 AA structures coupled with a HA structure by MM+ and QSAR+ properties. Computational hydrophobicity values were considered dependent variables and were related to the structural features obtained by molecular and quantum mechanics calculations by multiple linear regression approaches. The obtained model was validated, and the results indicated differing hydrophobicity between the MM+ and QSAR+ properties.