• Textile Coloration and Finishing
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• v.19 no.3
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• pp.12-17
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• 2007

In this study, we have investigated properties and behaviors of the indigo vat dyeings on synthetic fibers, namely PET and PTT/Spandex. In addition, indigo vat dyeing conditions such as dyeing temperature, dye concentration and pH were optimized. The finding results show that higher color strengths of indigo dyeings on the two types of applied fibers were obtained at $110^{\circ}C$ and $90^{\circ}C$, respectively. Furthermore, acid leuco dyeings on the fiber substrates using acetic acid and formic acid show higher dye uptake with compared to alkali leuco counterparts.

• KSBB Journal
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• v.28 no.5
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• pp.295-302
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• 2013

Indigo is utilized in various industries including textile dyeing, cosmetics, printing and medicinal products and its reduced form, leuco-indigo, is mainly used in these process. Chemical reducing agent (sodium dithionite, sodium sulfide, etc.) is preferred to use for the formation of leucoindigo in industry. In traditional indigo fermentation process, microorganisms can participate in the reduction of indigo and thus it has been known to reduce environmental pollution and noxious byproducts. However, in fermentation method using microorganisms it is difficult to standardize large scale production process due to low yield and reproducibility. In this study, we attempted to develop the indigo reduction process using microbial flora which was isolated from naturally fermented indigo vat or deduced by metagenomic approach. From the results of library analyses of PCR-amplified 16S rRNA genes from the traditional indigo fermentation vat sample (metagenome), it was confirmed that Alkalibacteriums (71%) was distinctly dominant in population. Some strains were identified after confirming that they become pure culture in nutrient media modified slightly. Four strains were separated in this process and each strain showed obvious reducing ability toward indigo in dyeing test. It is expected that the analyzed results will provide important data for standardizing the natural fermentation of indigo and investigating the mechanism of indigo reduction.