• Textile Coloration and Finishing
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• v.4 no.3
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• pp.116-121
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• 1992

This paper is on for a material to replace the petroleum-based resins used as adhesives for the fiber in rubber composite materials. The study limited to the reaction properties of tannin with formaldehyde. Tannin-formaldehyde(TF) reactions were carried out in aqueous media. Rates of reaction were strongly dependent on concentration, temperature, pH, and the mole ratio of tannin to formaldehyde. Viscosities of reaction mixtures were followed up to gelation. The reactivity of tannin-formaldehyde resins was greater than that of resorcinol-formaldehyde resins. To formulate an adhesive, a styrene-butadiene-vinyl pyridine terpolymer latex(L) was added to the TF. This preliminary results suggest that the condensed tannins have considerable promise as substitutes for resorcinol used in resin formulation for bonding of fiber to rubber.

• Elastomers and Composites
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• v.45 no.3
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• pp.199-205
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• 2010

Medium-density fiberboard (MDF) is widely used as an indoor building materials. However, formaldehyde resins, commonly used to bind MDF together, emit formaldehyde and other volatile organic compounds that cause health risk at sufficient concentration. In this study, condensed tannin having formaldehyde absorption ability was used to solve the problem of formaldehyde emission generated from surface material. The synthesis of melamine-formaldehyde resin and reaction of melamine-formaldehyde and condensed tannin were analyzed by FT-IR spectrum. Also surface properties, such as shear force, impact strength, tape adhesion, pencil hardness and gloss retention were measured. Free formaldehyde analysis was performed to analyze remaining unreacted formaldehyde. According to the results, the optimum shear force and impact strength could be obtained by 10 wt.% usage of condensed tannin. In cases of pencil hardness and gloss retention, the optimum properties could be obtained at 20 wt.% of condensed tannin. The amounts of formaldehyde emission of surface material containing 20 wt.% of condensed tannin was 59 ${\mu}g/m^2{\cdot}h$. The amounts of formaldehyde emission could be reduced 3 times by using 20 wt.% of condensed tannin.

• Korean Journal of Pharmacognosy
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• v.32 no.1 s.124
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• pp.68-71
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• 2001

For the use of tannins in the whitening-effect cosmetics, inhibitory effect against tyrosinase activity was determined. Three condensed tannins including gallocatechin, gallocatechin 3',4'-di-O-gallate and epicatechin 3-O-gallate and three hydrolyzable tannins, 1,2,6-tri-O-galloyl-${\beta}$-D-glucose, 2,3-(S)-HHDP-D-glucose and pedunculagin showed 15-29% mild inhibitory effects against tyrosinase activity.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.203-208
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• 2005

The aim of this experiment was to determine the chemical composition of six commonly utilized fodder trees and shrub species in Turkey, namely Glycrrhiza glabra L, Arbutus andrachne, Carpinus betilus, Juniperus communis, Quercus libari L and Pistica lentiscus and its relationship with gas production and estimated parameters when incubated with rumen fluid in vitro. There were significant (p<0.001) differences between leaves in terms of crude protein (CP), acid detergent fiber (ADF), total condensed tannin (TCT), bound condensed tannin (BCT) and soluble condensed tannin (SCT). Crude protein contents ranged from 5.74% (Juniperus communis) to 12.59% (Glycrrhiza glabra L). Acid detergent fiber contents ranged from 25.14% (Glycrrhiza glabra L) to 39.23% (Juniperus communis). Total condensed tannin (TCT) contents of leaves ranged from 4.34% (Quercus libari L) to 20.34% (Juniperus communis). Acid detergent fiber (ADF) and total condensed tannin contents of leaves were negatively correlated with gas productions and some estimated parameters. Potential gas productions (A) of Glycrrhiza glabra L, Arbutus andrachne, Quercus libari L and Pistica lentiscus were significantly (p<0.001) higher than those of Carpinus betilus and Juniperus communis whereas gas production rate (${\mu}_{24}$) of Pistica lentiscus was significantly (p<0.001) higher than the others. Time (h) to produce 50% of total gas pool size ($T_{50}$) of Juniperus communis was significantly (p<0.001) lower than that of Carpinus betilus whereas time (h) to produce 90% of total gas pool size ($T_{90}$) of Juniperus communis was significantly lower than the others except for Pistica lentiscus. The metabolizable energy (ME) contents of leaves ranged from 8.86 to 10.39 MJ $kg^{-1}$ DM. The results obtained in this study suggested that browse species had a significant effect on chemical composition, gas production and estimated parameters of leaves. Leaves from Glycrrhiza glabra L with a considerable amount of CP had a high rank value in terms of ME. Therefore leaves from Glycrrhiza glabra L may have a high potential value for small ruminant animals in terms of rumen and whole digestibility. Leaves from other species studied require protein supplementation when they are the only feed consumed by ruminant animals.

• Textile Coloration and Finishing
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• v.6 no.1
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• pp.19-27
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• 1994

Mimosa and Quebracho are, in general, tanned with leather skin, finished silk fabrics according to temperature, treatment time, tannin concetration, pH, and studies that relation between tannin weighting and various factors. This makes fundamental study on characteristic of tannin treated fabrics. and the results are as fallows : 1. λ$_{max}$ was found at 278.5nm for Mimosa. 279.5nm for Quebracho. Also a stability was good in standing time and heating. 2. The higher tannin treatment temprature was, the better tannin weighting effect was. But they were slightly decreased at over 8$0^{\circ}C$, and K/S was slowly increased. 3. As tannin treatment time increased, tannin weighting effect increased but they were decreased at over 8$0^{\circ}C$, 90min. 4. As tannin concentration increased, tannin weighting was increased. 5. In tannin weighting effect according to various pH conditions, the it's best range of pH were 3.5~5.5 of Mimosa, 2.5~3.5 of Quebracho.o.

• Fashion & Textile Research Journal
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• v.8 no.3
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• pp.343-348
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• 2006

This study aims to attain gray tone dyed goods by using tannin that is contained in green tea. Tannin is given general name of polyphenol, which has a characteristic that bonds with protein and it is used for food preservative that protects against bacteria, as well as its purpose of black tone dye for silk treatment that has been processed since its early ages. In particular, as tannin reacts with all kinds of metallic mordant and changes to various colors, when tannin acid is combined with iron, it becomes tannin steel and produces gray tone color. Tannin that is contained in green tea is condensed tannins and its structure does not hydrolyze, thus having flavan type structure. In order to find the suitable condition for processing tannin, UV-Vis part absorption spectrum of green tea tannin, dye ability based on temperature and time, reflection rate based on concentration, color changes based on acid treatment and alkali treatment, changes on surface based on concentration or metal mordant condition, and lightfastness were measured. Maximum absorption wavelength (${\lambda}_{max}$) of green tea tannin was at around 273nm, while strong absorption was also observed at below 350 nm. Dye ability of green tea tannin is done more easily on silk rather than cellulose fibers such as cotton, while the optimum condition for dyeing was observed to be at $60^{\circ}C$, for 20 minutes. As a result of acid treatment, the color of dye material consisted highly of gray tones and showed overall gray tone with the combined color of yellow and red after the alkali treatment. While it was observed that as dye concentration and metal mordant concentration increased, the color changed at counter-clockwise direction on the Y-scale of Munsell's scale of colors. Additionally, lightfastness was more on a normal fading.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.477-481
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• 1996

It has been shown that tannins have adverse effects on growth of animals and feed utilization. Tannins are usually classified into hydrolyzable and condensed types but the adverse effects are more marked in condensed tannin in hydrolyzable tannin. Furthermore, the principle condensed tannins found in banana fruits are pro types by the polymerization of flavan-3, 4-diols either alone or in combination with other flavonoids such as catechins. Tannin of the investigated banana(Banana; Musa sapientum LINN)fruits was fractionated into four or five molecular forms, according to the degree of polymerization by chromatography on a column of Sephadex LH-20. The protein-precitating capacity of the fraction noted tannins increased in degree polymerzation. The inhibitory effect of tannins on trypsin(EC 3. 4. 21. 4), ${\alpha}-amylase$(EC 3. 2. 1. 1) and lipase(EC 3. 1. 1. 3) activities in vitro also increased with the incraesed in degree of polymerization.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1134-1138
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• 2006

Forest tree leaves (12 different species) of semi hilly arid region of Punjab State were collected at 30-day interval throughout the year to assess the seasonal variations in tannin profile. Tannins were extracted and fractionated from fat free samples and data were analyzed statistically by $12{\times}12$ factorial design. The leaves of Anogeissus latifolia had the highest (p<0.05) concentration of total phenols (17.4%), net (15.9%) and hydrolysable (16.9%) tannins, followed by leaves of Acacia nilotica. Majority of the tree leaves selected had moderate levels (2-5%) of net tannins. Leaves of Carrisa had the highest (p<0.05) concentration of condensed tannins (CT), whereas the leaves of Anogeissus had the lowest (p<0.05) concentration of condensed tannins. The protein precipitable phenols (PPP) corresponded well with the net tannin content present in different tree leaves. Seasonal variation data revealed that in summer, net tannins and PPP decline in leaves of Bauhinia and Zizyphus whereas the net tannin content of Anogeissus and that of Carrisa increased during summer. The CT and PPP content in the leaves of Pheonix, Leucaena, Zizyphus and Ougenia increased in winter till spring season. Tree leaves generally had higher concentration of HT during summer months. It was concluded that leaves of leaves of A. nilotica, A. latifolia and L. leucocephala could serve as an excellent alternate feed stuffs for ruminants. However, leaves of Phoenix, Carrisa, Bauhinia and Dodonea should be avoided.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.6
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• pp.891-894
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• 1999

A field experiment was conducted with Calliandra calothyrsus of fifteen provenances to evaluate the variation in the condensed tannin content of fresh leaves. Plants were raised in a nursery for three months and planted in the field. Experimental design was line planting of double hedgerows (3 m long plot, 1/2 meter interval, 45 plants in each plot) with 5 replicates. Plants were lopped every 5 months and samples (10 different plants within a plot; 4 newly flushed leaves, 4 partially expanded leaves and 4 mature full expanded leaves from each of 10 trees in a plot) were collected and were put on ice before transfer to the laboratory. Proanthocyanidine was extracted in aqueous acetone, and total extractable proanthcyanidine (TEPA) and total proanthocyanidine (TOPA) were measured. In addition, proximate analyses were made of different provenances. Crude protein contents varied from 19.74% to 16.45%; in vitro organic matter digestibility ranged from 36.09% to 23.32%. TEPA content ranged from 11.22 to 16.01 (measured as absorbance at $550nm,\;g^{-1}$ DM) and TOPA from 24.57 to 31.72 (measured as absorbance at $550nm,\;g^{-1}$ DM) TEPA and TOPA had a positive correlation, whereas crude protein content of Calliandra was negatively correlated with TEPA and TOPA. Provenances, such as Georgesville (Belize), local, Coban (Guatemala), Patulul (Guatemala), Bombana (Mexico) can be selected on the basis of nutritive value of fodder.

• Elastomers and Composites
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• v.30 no.1
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• pp.32-41
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• 1995