• Journal of the Korea Furniture Society
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• v.11 no.1
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• pp.13-23
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• 2000

This study was carried out to investigate the wood properties for development the proper uses of lesser-known tree species. The tested species are Kebambang(Pentace sp.), Bawang-bawang(Dysoxylum alliaceum Bl .), Garu buaya( Gonystylus brunescens A. Shaw)grown in Indonesia. fundamental wood properties such as anatomical, physical, mechanical and chemical properties and characteristics related to wood processing were examined. The results are summarized as follows : The woods of these species are diffuse porous, coarse textured, and interlocked grained. The heartwood of Kebambang is distinguished clearly to the sapwood, but the heartwood of other species are not distinguished clearly to the softwood. The woods of Kebambang and Bawang-bawang have the moderate weight density and the low strength properties, but Garu buaya has the high weight density and the high strength properties. The woods of these species has high shrinkage. The sawing characteristics of Kebambang are excellent but the other species are moderate. The machining characteristics by planer and drying characteristics of these species are moderate. These woods has poor characteristics in bending processing and decay durability. The wood of Bawang-bawang has high content of the extractives and lignin.

• Journal of the Korean Wood Science and Technology
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• v.40 no.2
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• pp.141-146
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• 2012

The outer bark of Prunus sargentii was collected, air-dried and extracted with 70% aqueous acetone. Then it was successively partitioned with n-hexane, dichloromethane ($CH_2Cl_2$), ethyl acetate (EtOAc) and $H_2O$. From the EtOAc soluble fraction, four compounds were isolated by the repeated Sephadex LH-20 column chromatography. The isolated compounds were determined as (+)-catechin (1), (-)-epicatechin (2), taxifolin (3), and neosakuranin (4) by the spectroscopic analysis including $^1H$, $^{13}C$-NMR, and 2D-NMR spectrometers. The antioxidative activities on the isolated compounds and the separated fractions were evaluated by DPPH radical scavenging assay. The crude, EtOAc, and $H_2O$ soluble fractions indicated good antioxidative potential compared to the $CH_2Cl_2$ and n-hexane soluble fractions.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.42-48
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• 2000

Two stilbenoids and two flavonoids were isolated from ethylacetate fraction of ethanol extract of Morns bombycis heartwood. These four compounds were identified 2',3,4',5-tetrahydroxystilbene(oxyresveratrol), 3,4',5-trihydroxystilbene (resveratrol) as stilbenoids, and 2',3,4',5,7-pentahydroxyflavone(morin), 3,4',5,7-tetrahydroxyflavan((+)-afzelechin) as flavonoids by Mass and NMR spectroscopic analysis.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2008.04a
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• pp.222-228
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• 2008

The chemical composition and thermal, crystal characterization of oak mushroom waste were investigated in comparison with those normal oak wood for utilization of cellulose from oak mushroom waste. The oak mushroom waste contained a higher percentage of ash, and hot water extractives than oak wood. This results indicated that the materials inside the body are easily decomposed during the oak mushroom cultivation. The lower percentage of holocellulose and a-cellulose of oak mushroom waste caused by fungal decomposition too. Whereas, the thermal decomposition behavior and crystallinity of oak mushroom waste was similar to that of normal oak wood, which indicated that the cellulose characterization of oak mushroom waste is resistant to fungal decomposition. In additionally, a degree of polymerization of oak mushroom waste must be investigate for examination of cellulose crystalline characterization, especially.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.511-515
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• 2006

From the EtOAc soluble fractions of Platanus orientals Linn leaves, (+)-catechin (1), (+)-epicatechin (2), (+)-gallocatechin (3), kaempferol (4), quercetin (5), kaempferol-3-O-${\alpha}$-L-rhamnopyranoside (6), quercetin-3-O-${\beta}$-D-glucopyranoside (7) and tyrosol (8) were isolated. The structures of the isolated compounds were characterized by NMR and MS spectrometers. The antioxidative activities of the isolated compounds and fractions were evaluated by DPPH free radical scavenging method and the results indicated that compounds 1, 2, 3, 4, 5 and EtOAc soluble fraction exhibited greater activities than ${\alpha}$-tocopherol and BHT, while compounds 6, 8 and other fractions showed low activity compared to the controls.

• Journal of the Korean Wood Science and Technology
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• v.31 no.5
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• pp.43-48
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• 2003

From the leaves of S. japonica, three compounds were isolated and identified as follows : hypogallic acid, kaempferol and quercetin. The free radical scavenging activities of the isolated compounds were 98.2%, 96.2% and 90.2% at 100 ㎍/ml, respectively. Compound 1 (hypogallic acid) and compound 2 (kaempferol) indicated higher antioxidative activity compared with reference compound, BHT.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.3
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• pp.57-65
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• 2016

Indigo (Polygonum tinctorium L.) is a typical blue dye which had been used from ancient times. This study was going to shade the complicated traditional methods extracting indigo dye by the fermentation and producing as adsorbate on calcium hydroxide, which says so called as the 'Indigo lime'. Accordingly we were going to make indigo through the hydrolysis of the hot water extractives of indigo leaves simply. During hot-water extraction, ${\beta}$-glucosidase which required hydrolysis of the linkage between indigo and glucose was not activated. To achieve this goal, indican was acid-hydrolyzed to glucose and indigo. The acetic acid, citric acid, hydrochloric acid, and sulfuric acid were used for the hydrolysis of hot water extractives. The hydrolysis conditions of extractives performed in water bath at $80^{\circ}C$ for 120 minutes and in an autoclave for 120 minutes. In the acid hydrolysis of extracted indican by hot water, the indican yields of acetic acid and hydrochloric acid hydrolysis were higher than sulfuric acid in water bath. Also, the indican yield of hydrochloric acid hydrolysis was better than sulfuric acid in autoclave. The hot water extracted indican was confirmed by HPLC analysis and its structure was confirmed by UV-Vis and FT-IR spectroscopy, compared with isolated indigo and commercial synthesized indigo. This improved extraction and hydrolysis methods can be replace the traditional indigo making method.

• Journal of the Korean Wood Science and Technology
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• v.48 no.2
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• pp.231-244
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• 2020

As a way of finding value-added materials from waste medium density fiberboard (MDF), this study characterized cellulose nanocrystals (CNCs) isolated by ammonium persulfate (APS) oxidation using recycled MDF fibers. Chemical composition of the recycled MDF fibers was done to quantify α-cellulose, hemicellulose, lignin, nitrogen, ash and extractives. The APS oxidation was performed at 60 ℃ for 16 h, followed by ultrasonication, which resulted in a CNC yield of 11%. Transmission electron microscope images showed that rod-like CNCs had an average length and diameter of 167±47 nm and 8.24±2.28 nm, respectively, which gave an aspect ratio of about 20. The conductometric titration of aqueous CNCs suspension resulted in a carboxyl content of 0.24 mmol/g and the degree of oxidation was 0.04. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy clearly showed the presence of carboxyl group on the CNCs prepared by the APS oxidation. The change of pH of the aqueous CNC suspension from 4 to 7 converted the carboxyl group to sodium carboxylate group. These results showed that the APS oxidation was facile and CNCs had a one-step preparation method, and thus suggested an optimization of the oxidation condition in future.

• Journal of the Korean Wood Science and Technology
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• v.34 no.3
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• pp.90-98
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• 2006

The purpose of this study was to estimate natural dyeing properties of Korean traditional paper (Hanji). Korean traditional paper, which made from bleached bast fiber pulp of Broussonetia kazinoki was used as base paper. As dyestuffs, hot water extractives of Phellodendron amurense bark, Rosa multiflora leaf and stalk, and Rubia cordifolia root and methanol extractives of Lithospermum erytrorhizon root were used. $Al_2(SO_4)_3$ and $Fe(OH)(CH_3COO)_2$ 0.5% solution were used as mordant. Soybean juice (10%), chitosan (0.1%), and skim milk (2%) solutions were used as auxiliary dyeing agents. Accelerated aging treatments of natural dyed Korean traditional papers were undergone at following conditions: exposure temperature, $80^{\circ}C$ relative humidity, 60%; wavelength, 340 nm; UV irradiance, $0.67W/m^2/nm$ exposure time, 24, 48, and 72 hours. Colors, color difference, and color fastness were examined for estimation of natural dyeing characteristics. The auxiliary dyeing agents treated Korean traditional papers were more superior the dyeing effectiveness about dyestuffs than untreated Korean traditional papers. The dyeing effectiveness of soybean juice treated Korean traditional paper was superior to the others. The color fastness of Korean traditional paper, which was dyed with Rubia cordifolia root extractives, was most inferior to the others.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.51-57
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• 2002

Antimicrobial and antioxidative activites on heartwood extractives of domestic species were investigated to develop a natural fungicide or preservative. One steroid, stilbene derivatives and two flavonoids were isolated from heartwood of Robinia pseudo-acacia which has been selected due to its high antioxidative activity among the tested species. The structures were determinded as: 3-𝛽-stigmast-5-en-3-ol(daucosterol), 3,3'4,5-tetrahydroxystilbene, 3,3'4'5,7-pentahydroxyflavone(robinetin) and 3,3'4'7-tetrahydroxyflavanone(fustin) respectively on the basis of spectroscopic data and chemical correlations. According to the results of free radical scavenging activity, 3,3'4'5,7-pentahydroxyflavone was evaluated as the highest antioxidative compound among the four compounds and showed higher radical scavenging activity than those of 𝛼-tocopherol and butylated hydroxytoluene(BHT), one of the strongest synthetic antioxidants. 3,3'4'5-Tetrahydroxystilbene and 3,3'4'7-tetrahydroxyflavanone showed higher antioxidative activities than that of 𝛼-tocopherol. However, 3-𝛽-stigmast-5-en-3-ol did not show free radical scavenging activity. In this regard, it could inferred that high antioxidative activity of extractives of R. pseudo-acacia was derived from 3,3'4'5'7-pentahydroxyflavone, 3,3'4'5-tetrahydroxystilbene and 3,3'4'7-tetrahydroxyflavanone.