Experimental Determination of Octanol–Water Partition Coefficients of Selected Natural Toxins Article Swipe
YOU?
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· 2020
· Open Access
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· DOI: https://doi.org/10.1021/acs.jced.9b01129
· OA: W3007829240
Natural toxins are widely occurring,\nhighly diverse organic compounds\nproduced by, for example, plants or fungi. In predictive environmental\nfate and risk assessment of organic chemicals for regulatory purposes,\nthe octanol–water partition coefficient (<i>K</i><sub>ow</sub>) remains one of the key parameters. However, experimental\ndata for natural toxins are largely missing, and the current estimation\nmodels for <i>K</i><sub>ow</sub> show limited applicability\nfor multifunctional, ionizable compounds. Thus, log <i>K</i><sub>ow</sub> data were first experimentally derived for a diverse\nset of 45 largely ionizable natural toxins and then compared with\nthe predicted values from three different models (KOWWIN, ACD/Percepta,\nand Chemicalize). Both approaches were critically evaluated with regard\nto their applicability for multifunctional, ionizable compounds. The\nminiaturized shake-flask approach allowed reliable quantification\nof pH-dependent partitioning behavior for neutral, acidic, and basic\nionizable natural toxins. All the analyzed toxins are rather polar\nwith an average log <i>K</i><sub>ow</sub> < 1 and an\nobserved maximum log <i>K</i><sub>ow</sub> of 2.7. Furthermore,\nthe comparison of experimental data for the neutral form of ionizable\ntoxins with those of commonly used prediction models showed that the\nlatter match the former with only slightly increased errors. The Chemicalize\ntool gave the best overall predictions for the dataset generated here,\nwith a mean absolute error of 0.49.
