Speaker
Description
Anthocyanins are glycosidic flavonoid pigments responsible for most of the red, purple, and blue colors in flowers, fruits, leaves, stems, bracts, seeds, and pollen. These multifunctional secondary metabolites reside primarily in epidermal vacuoles and act as antioxidants, providing photoprotection, contributing to wound healing, and offering freeze protection. In the crowded vacuolar environment (pH 3–6), anthocyanins undergo a complex series of molecular transformations governed by pH, metal ions, copigments, and concentration. Color is determined by kinetic and thermodynamic relationships among anthocyanin species, as well as by concentration-dependent associative self-assembly.
Microscopic analysis of live epidermal cells reveals multiple anthocyanic phases with sizes ranging from 1–10 μm. Self-assembly is driven by intra- and intermolecular π–π stacking, hydrogen bonding, ion pairing, and charge-shift interactions, leading to amphiphilic micelle formation. These associations can generate spatial patterning in petals. In our mathematical framework, pattern formation results from collective behavior due to emergent structures and pathways arising from interactions among many coupled species. We have also developed microfluidic, self-reporting spectroscopic methods to study these phase behaviors.
