Unveiling the Hidden Costs of Domestication: Health-Promoting Compounds Lost in Maize

Over centuries, the wild grass teosinte has been transformed through selective breeding into modern maize (Zea mays), prioritizing higher yields but sacrificing health-enhancing compounds like bioactive peptides and key metabolites. While the genetic shifts from domestication are well-documented, the resulting phenotypic changes – especially in protein composition and bioactivity – remain largely untapped. Therefore, this worked aimed at exploring those lost bioactive compounds in 26 modern maize, 25 landraces, and 25 teosinte varieties.

We found that that the raw kernels of teosinte varieties had three times higher protein content than the other two varieties. Moreover, we found significantly higher traces of antioxidant metabolites like quinic acid, caffeic acid, and chlorogenic acid in teosinte kernels. After simulated gastrointestinal digestion, there was no significant difference in the level of most metabolites, except for quinic acid and its derivatives levels, which were significantly higher in teosinte. Moreover, peptide profiling uncovered that digested teosinte varieties were rich in dipeptides and tripeptides containing hydrophobic residues, known to possess bioactive properties. Later, in-vitro studies showed that teosinte digesta significantly reduced oxidative stress in HT-29 cells. These findings indicate that domestication led to the loss of potential health-beneficial compounds, like quinic acid and bioactive peptides, once abundant in teosinte.