Uptake of Artificial Sweeteners in Wheat ( <i>Triticum aestivum</i> L.): Subcellular Distribution and Nontarget Identification of New Metabolites

Artificial sweeteners (ASs), which serve as vital alternatives to sucrose, have been detected in agricultural soils and crops. However, knowledge gaps persist regarding their bioaccumulation in plants, which is vital for assessing ecosystem risks. This study examined saccharin (SAC) and acesulfame (ACE) absorption, translocation, and biotransformation in plants via hydroponic experiments. Inhibition studies revealed that root uptake is an active, energy-dependent process involving aquaporins and anion channels. Their hydrophilicity enabled upward movement to above-ground tissues through transpiration and storage in water-soluble cellular components. High-resolution mass spectrometry detected 11 metabolites, proposing potential degradation pathways and identifying, for the first time in plants, phase II metabolites undergoing methylation and glucuronide conjugation. Ecotoxicity predictions indicated that hydroxylated and methylated metabolites were more toxic. This study is the first to explore the mechanisms of AS accumulation and biotransformation in plants, providing deeper insights into their in-plant behavior.