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Chapter 15 · Showing Your Colors Sustainably! - Natural Dyes
15
. Fig. 15.6 Indigo plant (left) and woad (right) (© Dr. Renate Kaiser-Alexnat, Institut für Färbepflanzen, Michelstadt/
Germany)
N
H
O
O
HO
OH
OH
CH 2
OH
Enzymatic
cleavage
N
H
OH
O 2
2x
N
H
O
H
N
O
Indigo
N
H
OH
H
N
HO
Leucoindigo
Indican
Indoxyl
Reduction
Oxidation
. Fig. 15.7 Production of natural indigo (and conversion to indigo white)