Abstract
Indigo dyeing can be performed by producing indigo within fiber from indican and the enzyme in the fresh leaves of the indigo plant or by reducing indigo in a vat. This method, however, is applicable only when fresh leaves can be obtained, because indican in the leaves changes to indigo when they die. To find a good method to maintain indican in the leaves, its content was measured after various drying processes. Drying with a microwave oven was found to be effective in keeping indican in the leaves and the content of indican did not decrease for more than several months. On the other hand the enzyme in the leaves was found to exist in the naturally dried leaves for a long time. This enzyme hydrolyzes indican to indoxyl which turns into indigo by oxidation. These results indicate that dyeing with indican can be achieved in all seasons by using both microwave dried leaves and naturally dried leaves.
