Thionins

Low molecular weight proteins which occur in the seeds of several plant species and show antimicrobial activity. Thionins — small, cysteine-rich, basic peptides from wheat, barley, and other cereals — disrupt microbial membranes, contributing to the seed‘s defence against fungi and bacteria. Their potent antimicrobial action has attracted interest as natural food preservatives and as templates for engineered antimicrobial peptides, though toxicity and stability questions remain. In plant science they are model defence proteins; in food technology they illustrate the broader search for plant-derived hurdles that could supplement conventional preservation with clean-label appeal.