Natural pigments from six species of Thai plants extracted by water for hair dyeing product application

► Six plants extracted with water at 100 °C, pH9 gave pigment to generate eco-friendly dyes. ► Hair dyed with plant extracts, ascorbic acid, ferrous sulfate had excellent dyeability. ► The interaction of hair protein and natural pigment mixtures had high-affinity analyzed by SPR. ► Six plant extracts could be applied for hair dyeing, non-food and food industries.