Denim Bleaching

Laccase-catalyzed textile dye-bleaching has found its use in finishing indigo-dyed cotton fabric, denim [150-155, 155a]. Commercial laccase products from Novozymes, first DeniliteĀ® and later Denilite IIĀ®, contain a fungal laccase and a redox mediator [74, 150]. With the help of the mediator, the laccase can effectively catalyze the oxidation of the (insoluble) blue indigo into the essentially colorless isatin. The traditional chlorine-based bleaching, applied as the final step in finishing of indigo-dyed denim when the fashion requires a bleached look, is replaced by a much more environmentally acceptable method, whose benefits include better processing control, reduced water usage, and less pollution.

This application is an interesting case from the point of view of enzyme technology development. Mediated oxidoreductase (peroxidase or laccase) systems have been actively pursued for laundry detergent applications, particularly for "dye-transfer inhibition" during washing (or bleaching of fugitive textile dyes in the wash liquor) [56]. The research encountered a major difficulty in how to bleach the unwanted, desorbed dye while preventing fading of the dyed garments. Although a mediated laccase system for household laundry has yet to be developed due to this difficulty, the research was redirected towards an application where bleaching of dyed garments is desired, leading to the successful laccase product for denim bleaching in the textile industry.

Heal Yourself With Qi Gong

Heal Yourself With Qi Gong

Qigong also spelled Ch'i Kung is a potent system of healing and energy medicine from China. It's the art and science of utilizing breathing methods, gentle movement, and meditation to clean, fortify, and circulate the life energy qi.

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