Indigo cotton yarn
 A glucosyl protecting group enables control over the timing and location of indigo dyeing.
Bio-indican can be used as an effective, reductant-free cotton textile dye. (a) Top row, Pure indican with no β-glucosidase (BGL); pure indican with β-glucosidase; bio-indican with β-glucosidase. Bottom row, Indigo, nonreduced; indigo, reduced with sodium