• Textile Coloration and Finishing
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• v.20 no.6
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• pp.51-62
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• 2008

The purpose of this study was to check color change depending on dyeing conditions when silk fabrics was dyed with gromwell and to investigate mordant effect when synthetic tannin was used as a mordant. First, when silk fabrics were dyed with gromwell, the change of color, brightness and chroma were examined by measuring K/S value, a, b value, L value and C value depending on dyeing condition. Second, color, brightness and chroma differences which appeared after mordanting with synthetic tannin were investigated and muti-functional mordanting effect was confirmed with dyeing fastness, antibiosis. As a result of color analysis of gromwell, it was proved that the main pigment of gromwell was shikonin. Color was red purple at pH 3 when silk fabrics were dyed with gromwell. But It became greenish and bluish as temperature rose and time passed by. And it grew reddish and yellowish as concentration level reached higher. The color became purple at pH 5 and purple blue at pH 7. Both at pH 5 and pH 7, it became greenish and yellowish, as temperature went up and time ran by. And it became reddish with concentration increasing. Brightness and chroma decreased with temperature and concentration increasing as well as time passing by. After mordanting with synthetic tannin, the color became less reddish at pH 3 and reddish-yellowish at pH 5 and pH 7. The brightness increased and the chroma decreased. At all pH, the color, the brightness and the chroma became similarly by synthetic tannin mordanting. Dyeing fastness of synthetic tannin mordanted fabric was higher than that of non-mordanted fabric. Especially, wet fastness at pH 3 improved from 1 grade before synthetic tannin mordanting to $3{\sim}4$ grade after tannin mordanting. Antibiosis was improved by gromwell dyeing and synthetic tannin mordanting.

• Textile Coloration and Finishing
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• v.20 no.2
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• pp.59-65
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• 2008

The tannin acid and the enzymes have been used in order to improve the ruggedness in laundry and the absorption of dyes and pigments in the textile industry for several years. The enzyme processing on the protein fiber minimizes the damage of the entire fiber and improves the dyeability by effectively modifying only the hydrophobic surface. This study tried out the structural observation by applying the Castanea crenata sieb. et. zucc. containing abundant tannin to the hair dyeing as the natural dyeing pigment along with Protease of Rhizopus sp. The dyeability was improved as compared to the dyeing using only the synthetic tanning and iron mordant. When the depth of pigment was higher in accordance with the surface observation, the enzyme dissolution had impact on dyeing and so the keratin layer on the hair surface. Accordingly, it was found that the appropriate depth was between 0.01 and 0.03%. It was estimated that 0.1% protease would treated within 30min. Consequently, it would cause the good reaction with the functional group of tannin pigment.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.5
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• pp.417-426
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• 2010

In this study, ten different bio-adsorbents were prepared by immobilization of vegetable tannins such as mimosa(Catechol Tannin) and chestnut(Pyrogallol Tannin) on the collagen matrix which was derived from during leather manufacturing processing. Removal efficiency of Cu(II), Cd(II), Zn(II), Pb(II), Cr(III) by each bio-adsorbent in synthetic wastewater was evaluated by a laboratory-scale batch reactor at different reaction conditions. When mimosa was used as a vegetable tannin, the penetration efficiency of mimosa into the inner bundle of fiber depended on the dose of the naphthalene condensated penetrant; 3% ${\geq}$ 1.5% > 0%. For all bio-adsorbents, removal of heavy metal ions was not observed below pH 3.0 but was rapidly increased between pH 3.0 and 6.0, showing near complete removal of all heavy metal ions except Zn(II) above pH 6.0. Removal of Cr(III) was quite similar for all bio-adsorbents while removal of Cu(II), Zn(II) and Pb(II) was higher by bio-adsorbents immobilized with chestnut than that by mimosa. Adsorption of Pb(II) and Cu(II) by S10 bio-adsorbent was little affected by the presence of monovalent and divalent electrolytes as well as variation of 1000 times ionic concentration with $NaNO_3$.

• The Korean Fashion and Textile Research Journal
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• v.14 no.4
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• pp.648-659
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• 2012

This research categorizes fundamental data needed to develop eco-friendly fabrics treated with bamboo leaf & pine leaf extracts. The effect of mordant on those fabrics was analyzed through the measurement of mechanical properties and the estimation of primary hand values for cotton and silk fabrics dyed with bamboo leaf and pine leaf extracts that were later treated with various mordants. When cotton was dyed with bamboo leaves and pine leaves extracts, EM, WT, 2HB, 2HG, 2HG5, LC, T, and W increased however, RT, SMD, and RC decreased compared to raw cotton fabric. The B, G, and MIU increased after mordant treatment to the dyed cotton and resulted in a stiffer and rougher cotton's hand. EM, WT, RT, MIU, WC, T, and W increased (in terms of silk); however, LT, B, 2HB, G, 2HG, 2HG5, MMD, SMD, and LC decreased compared to raw silk fabric. Similar to the dyed cotton, mordant treatment increased the MIU and LC of dyed silk subsequently, the hand became stiffer and rougher. A greater tannin adsorption results in an increased mechanical property and the primary hand value. For both fabrics, mordant treatment made its smoothness drop. However, the scale of drop for cotton was significant, while the scale of the drop for silk was minor. In terms of type of mordant, femordant and natural-mordant treatment influenced the tensile, shear, surface properties of fabrics, and primary hand values more than Cu-mordant and synthetic-mordant in addition, this increased the stiffness, hardness, and roughness of fabrics.

• Microbiology and Biotechnology Letters
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• v.18 no.6
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• pp.591-598
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• 1990

Six species under the basidiomycetes were screened for extracellular tannase (tannin acyl hydrolase EC 3.1. 1.20) production in submerged culture and Lenzites betulina was found to be most effective for the production of tannase. The optimum cultural conditions for tannase production were $25^{\circ}C$, pH 6.0 and 21 days of culture period, The efficient composition of culture medium for the production of tannase was performed in synthetic medium containing tannic acid, 2g; sucrose, 5g; bacto-peptone, 2g; ,$ KH_2PO_4, \;2g,\; MgSO_4.7H_2O \;0.5g,\; CuS0_4.5H_2O$, 2 mg; thiamine HCl, 100 ug and distilled water 100 ml, The tannase produced from Lenzites bdulin*r was 223.3 unit (umole of gaUic acidiml of brothlmin). The tannase had an optimal reaction conditions ofpH 6.0 and temperature of $40^{\circ}C$. The enzyme was stable at temperature below $40^{\circ}C$ and lost its activity by 50% above $60^{\circ}C$. And the stable pH range was 5.5 to 6.0.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.2
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• pp.256-265
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• 2009

The purpose of this study is to check color change, color fastness, increase wt., antibiosis, and UV-protection efficiency depending on gallnut concentrations and mordanting methods, when silk fabrics dye with gromwell according to pH. This results will contribute in developing of natural mordant with multi function. The results are as follows. ${\lambda}_{max}$ of Gallnut extracts was near 299 nm. When gallnut was used as a mordant, at all pH levels, pre-mordanted fabrics had red color and post-mordanted ones had red-purple color which was closed to natural color of gromwell. Brightness of post-mordanted fabrics was higher than that of pre-mordanted fabrics. In the case of chroma, pre-mordanted fabrics was higher than post-mordanted fabrics. There was no significant difference of color, brightness, and chroma depending on gallnut concentration. As mordanting concentration increased, fabric weight gradually went up and increase weight reached maximum $17{\sim}19%$. At all pH levels, color fastness improved by pre-mordanting and post-mordanting, and it showed the maximum $4{\sim}5$ grade of wet fastness and 5 grade of dry cleaning. Antibiosis of silk fabric was improved by gromwell dyeing and synthetic tannin mordanting. Antibiosis of gallnut extracts was excellent. The color fastness and antibiosis were preserved after 10 cycle dry cleaning. UV-protection efficiency was excellent by dyeing with gromwell and mordanting with gallnut.

• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.250-257
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• 2017

Eight hydrolyzable tannin compounds, such as gallic acid (1), methyl gallate (2), kurigalin (3), 1,2,3,6-tetra-O-galloyl-${\beta}$-D-(+)-glucose (4), 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-(+)-glucose (5), 6-m-digalloyl-1,2,3,4,6-penta-O-galloyl-${\beta}$-D-(+)-glucose (6), isocorilagin (7), macabarterin (8), were isolated from the EtOAc and $H_2O$ soluble fractions of Katsura tree (Cercidiphyllum japonicum) leaves, wood and bark. Then antioxidative and anti-inflammatory activity were evaluated on the each isolated compound. The antioxidative test was DPPH radical scavenging activity and all of the isolated compounds indicated much higher antioxidative values compare to the controls, BHT and ${\alpha}$-tocopherol. In the anti-inflammatory test measuring nitric oxide (NO) inhibition activity, methyl gallate, 1,2,3,6-tetra-O-galloyl-${\beta}$-D-glucose and 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-glucose inhibited NO production, and especially, methyl gallate showed high inhibition activity. However, the anti-inflammatory activity of the hydrolyzable tannins did not show positive effect. Based on the above results, the hydrolyzable tannins of katsura tree may be used as one of the natural biomass sources that can substitute with the synthetic antioxidant.