• YAKHAK HOEJI
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• v.45 no.2
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• pp.169-179
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• 2001

In previous study, Gyrophora esculenta showed significant inhibitory effect on $\alpha$-glucosidases in vitro and blood glucose elevation in vivo. In the isolating process of active substance, orcinol was separated from Gyrophora esculenta. Orcinol is known to be toxic, therefore, in this study, it was analysed by the TLC densitometry method for quantitative determination from Gyrophora esculenta. The average amount of orcinol of Gyrophora esculenta was 0.2%. For the purpose of removing orcinol, the water extract of Gyrophora esculenta was sequentially fractionated by organic solvents, and the acute toxicity of each fraction was assessed in mice. Among them, the LD50 of butanol fraction was 1.19 g/kg(p.o.) and the weight increase of mice in that group was somewhat retarded.

• Bulletin of the Korean Chemical Society
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• v.9 no.2
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• pp.71-77
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• 1988

Boron trifluoride etherate on alumina catalyses the condensation of orcinol and monomethyl orcinol with cyclic allylic alcohols : in contrast to parallel reactions with boron trifluoride etherate in solution the products obtained undergo intramolecular cyclisations.

• Korean Journal of Food Science and Technology
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• v.3 no.2
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• pp.105-109
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• 1971

Effects of perchloric acid (PCA) and trichloroacetic acid (TCA) on the color generation by orcinol reaction were systematically investigated. When the concentration of PCA on hot acid treatment was varied from 1 through 5 to 10%, and then the concentration of PCA on orcinol reaction was adjusted to 5% of reaction volume, no difference in the color generation was observed between 5 and 10% of PCA, but clearly observed between 1 and 5% PCA. When RNA was treated in 5% hot PCA and then PCA concentrations on orcinol reaction were adjusted to 5% and 10%, respectively, remarkable differences in color generation were observed. When RNA was treated in 10% hot PCA and then PCA concentration on orcinol reaction was adjusted to 5% no difference in color generation between 5% and 10% hot acid treatment was observed. The results show that PCA concentration must be adjusted prior to orcinol reaction.

• Korean Journal of Pharmacognosy
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• v.30 no.3
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• pp.295-300
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• 1999

Seven compounds were isolated from the n-BuOH extract of the dried stem barks of Rhus javanica L. On the basis of physico-chemical, spectroscopic evidences and comparison with authentic samples, the compounds $1{\sim}7$ were identified as gallic acid (1), methyl gallate (2), scopoletin (3), scopolin (4), $1,\;2,\;3,\;4,\;6-penta-O-galloyl-{\beta}-D-glucose$ (5), orcinol (6) and $orcinol-{\beta}-D-glucoside$ (7). Among these compounds, scopolin, $orcinol-{\beta}-D-glucoside$ were isolated from this plant for the first time.

• Journal of the Korean Wood Science and Technology
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• v.33 no.5 s.133
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• pp.86-91
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• 2005

Six compounds were isolated from the EtOAc and $Et_2O$ fractions of the bark of Rhus chinensis by repeated column chromatography with $SiO_2$ and Sephadex LH-20. The structures were determined by instrumental analysis using MS and NMR spectrophotometer as: gallic acid (1), methyl gallate (2), 6, 7-dimethoxycoumarin (3), orcinol-${\beta}$-D-glucoside (4), scopoletin (5), semialactone (6). Among these compounds, 6,7-dimethoxycoumarin (3) was isolated from this plant for the first time. To measure the antioxidant activity, the DPPH radical scavenging activity test was performed. Gallic acid (1) showed the strongest activity, while orcinol-${\beta}$-D-glucoside (4), semialactone (5) and scopoletin (6) had the low activities.

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.221.1-221.1
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• 2000

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.457-458
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• 1992

• The Korean Journal of Mycology
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• v.24 no.3 s.78
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• pp.237-242
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• 1996

Two depsides, medicinal herb products isolated from the methanol extract of Umbilicaria esculenta, inhibited human synovial fluid Phospholipase $A_2\;(PLA_2)$ ($IC_{50}$ of 0.22 and 0.26 mM, respectively). In the course of screening for antiinflammatory compounds from natural products, we successfully isolated two depsides $PLA_2$ inhibitory compounds, Orcinol and methyl orsellinic acid. The compounds were identified as orcinol and methyl orsellinic acid on the basis of various NMR studies including $^1H,\;^{13}C$ and DEPT experiments.

• Analytical Science and Technology
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• v.10 no.4
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• pp.282-290
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• 1997

The sorption and desorption properties of U(VI), Th(IV), Zr(IV), Cu(II), Pb(II), Ni(II), Zn(II), Cd(II) and Mn(II) ions on XAD-16-[4-(2-thiazolylazo)orcinol] (TAO) chelating resin were studied by elution method. The effect was examined with respect to overall capacity of each metal ion, separation of mixed metal ions, flow rate and concentration of buffer solution for optimum condition of sorption. The overall capacities of some metal ions on this chelating resin were 0.35nmol U(VI)/g resin, 0.49nmol Th(IV)/g resin, 0.41nmol Cu(II)/g resin, and 0.31nmol Zr(IV)/g resin, respectively. The elution order of metal ions obtained from breakthrough capacity and overall capacity at pH 5.0 was Th(IV)>Cu(II)>U(VI)>Zr(IV)>Pb(II)>Ni(II)>Zn(II)>Mn(II)>Cd(II). The group separation of mixed metal ions was possible by increasing pH in pH range 2~5 at a flow rate of 0.28mL/min. Characteristics of desorption were investigated with desorption agents such as $HNO_3$, HCl, $HClO_4$, $H_2SO_4$, and $Na_2CO_3$. It was found that 2M $HNO_3$ showed high desorption efficiency to most of metal ions except Zr(IV) ion. Also, desorption and recovery of Zr(IV) ion were successfully performed with 1M $H_2SO_4$. Recovery of trace amount of U(VI) ion from artificial sea water was over 94%. The chelating resin, XAD-16-TAO was successfully applied to group separation of rare earth metal ions from U(VI) by using 2M $HNO_3$ as an eluent.

• Analytical Science and Technology
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• v.13 no.3
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• pp.323-331
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• 2000

Two chelating resins, XAD-16-TAC and XAD-16-TAO were synthesized by Amberlite XAD-16 macroreticular resin with 2-(2-thiazolylazo)-p-cresol (TAC) and 4-(2-thiazolylazo)-orcinol (TAO) as functional groups. The sorption behaviour of Zr(IV), Th(IV) and U(VI) with two chelating resins were examined with respect to the effect of pH and masking agent by batch methods. It was obtained that the optimum pH was in the range of 5-6, and two chelating resins showed good separation efficiency of Zr(IV) or Th(IV) by using $NH_4F$ as a masking agent. Characteristics of desorption were investigated with 0.1-2 M $HNO_3$ as desorption agent. It was found that 2 M $HNO_3$ showed high desorption efficiency to most of metal ions except Zr(IV). XAD-16-TAC resin is applied to separation and preconcentration of trace Zr(IV) from mixed metal ions. Also, Th(IV) ion can be successfully separated from U(VI) and Zr(IV) ion by using XAD-16- TAO resin.