• Journal of the Korean Wood Science and Technology
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• v.31 no.3
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• pp.17-23
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• 2003

As a fundamental study of developing sawdust board from thinning softwood logs from three species (Pinus densiflora S. et Z., Larix leptolepis G. and Pinus koraiensis S. et Z.), this study examined the effect of board density and resin content on physical and mechanical properties of sawdust board. As the board density increase, thickness swelling, bending strength, and Brinell hardness increased while water absorption decreased. With increasing the resin content, the bending strength and hardness increased while water absorption and thickness swelling decreased. The board made of L. leptolepis was slightly low in its water absorption, and the one made of P. koraiensis was a little high in its bending strength, while there was no definite difference between each kind of trees in their hardness values.

• Analytical Science and Technology
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• v.14 no.4
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• pp.349-355
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• 2001

A series of micro- and mesoporous activated carbons were prepared from phenolic resin using a metal treated chemical activation methodology. $N_2$-adsorption data were used to characterize the surface properties of the produced activated carbons. Results of the surface properties and pore distribution analysis showed that phenolic resin can be successfully converted to micro- and mesoporous activated carbons with specific surface areas higher than $962.3m^2/g$. Activated carbons with porous structure were produced by controlling the amount of metal chlorides($CdCl_2$, $CuCl_2$). Pore evolvement was shown to be most effected by the incremental addition of metal chloride. From the thermodynamic DSC data, enthalpy formations(${\Delta}H$) of first endothermic reaction were increase with the incremental addition of metal chloride.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.755-762
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• 1995

A phenolic resin industrial wastewater containing about 41,000 mg/l of phenol and 2,800 mg/l of formaldehyde was biologically treated by a mixed culture GE2 immobilized on ceramic beads. This study was carried out with three experimental groups : Control-only added the sludge of papermill wastewater ; GE2 treatment-added GE2 to Control ; Ceramic treatment-applied ceramic carrier to GE2 treatment. When the original wastewater was diluted 80 times with aerated tap-water, influent COD$_{Mn}$ WaS 1,140 mg/l and that of the effluent was in the range of 22-35 mg/l, which was not much different among the experimental groups. However, at 20-times dilution, influent COD$_{Mn}$ was 4,800 mg/l and the effluent COD$_{Mn}$ of Control, GE2 treatment and Ceramic treatment was 179, 128 and 94 mg/l, respectively. COD$_{Mn}$, removal efficiency by Ceramic treatment was the highest, at 98.0%. At this time, the effluent phenol concentration of Control, GE2 treatment and Ceramic treatment was 10.71, 7.93 and 5.60, respectively. As the dilution times decreased, the removal efficiency of COD$_{Mn}$ and phenol did not change much, but COD$_{Mn}$ and phenol concentration of the effluent increased. Consequently, it is likely that the phenolic industrial wastewater containing phenol and formaldehyde can be biologically treated using a GE2 and ceramic carrier and that at 40-times dilution, the effluent completely meets the effluent standards for industrial wastewater treatment plant.

• Korean Journal of Pharmacognosy
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• v.42 no.2
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• pp.149-154
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• 2011

Seventeen 30% EtOH extracts from the Compositae plants collected in Gangwon-do, Korea during autumn season were analyzed by HPLC using three standard caffeoylquinic acids (chlorogenic acid, 3,5-di-O-caffeoylquinic acid, 3,5-di-Omuco-quinic acid) and six flavonoids (rutin, isoquercitrin, astragalin, quercitrin, quercetin and kaempferol) to find the composition of phenolic compounds and also assayed to evaluate the peroxynitrite (ONOO$^-$) scavenging effect. The extracts with $IC_{50}$ values less than 2.0 ${\mu}g/ml$ were as follows: Aster tartaricus ($IC_{50}$, $1.26{\pm}0.10\;{\mu}g/ml$), A. maaki ($1.45{\pm}0.03\;{\mu}g/ml$), Solidago virga-aurea, ($1.45{\pm}0.03\;{\mu}g/ml$), Picris hierraciodes var. glabrescens ($1.45{\pm}0.04 \;{\mu}g/ml$), Lactuca triangulata ($1.50{\pm}0.09\;{\mu}g/ml$), Chrysanthemum zawadskii ssp. acutilobum, ($1.79{\pm}0.14\;{\mu}g/ml$). Particularly, the proportion of total phenolic compounds measured in the extract of L. triangulata was highest as the value 54.51%.

• Journal of Ginseng Research
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• v.34 no.3
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• pp.198-204
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• 2010

Korean ginseng (Panax ginseng C.A. Meyer) preserved in syrup, known as ginseng Jung Kwa (GJK), is a popular traditional snack in Korea. We investigated the effects of heat processing time on total phenolic content and antioxidant capacity of GJK. Water extract was prepared from GJK with different heat processing times, 3 hours (GJK-3), 6 hours (GJK-6), or 12 hours (GJK-12), with sonication for 2 hours. The GJK extract contained total phenolic content in the following order: GJK-12 (2.28%)>GJK-6 (1.57%)>GJK-3 (1.29%). Both the peroxy and hydroxyl radical-scavenging activity and cellular antioxidant capacity of GJK extract was significantly enhanced with increasing heat processing time. The hydroxyl radical-scavenging activity of GJK-12 extract was greater than that of the GJK-3 and GJK-6 extracts, consistent with metal chelating capacity and reducing capacity. In a cellular model, the GJK extract effectively reduced 2,2'-azobis(2-amidinopropane) dihydrochloride, $Cu^{2+}$-, and $H_2O_2$-induced oxidative stress, with GJK-12 and GJK-6 extracts demonstrating greater cellular antioxidant capacity than the GJK-3 extract. These results suggest that heat processing time can contribute to the antioxidant capacity of GJK and that GJK extract may have the potential to be used as an effective dietary antioxidant to prevent oxidative stress-related diseases.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.300.1-300.1
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• 2002

From 4 fractions as n-hexane (yield. 0.09%), EtOAc (0.48%). BuOH (3, 0%) and H2O (5.17%) fraction from MeOH extract (11, 64%) of powdered Gastrodia elata Rhizoma (GER) for the activity-guided separation on anti-inflammatory action. some biological active agents were isolated by column chromatography (column. silica gel: elution solvent. CHCl3 : MeOH) according to the method of Junko Hayashi et. al. and Heihachiro Taguchi et. al. Compound I, II, III, IV, V as phenolic derivatives were isolated in the EtOAc and BuOH fractions. (omitted)

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1476-1480
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• 2009

Antioxidant activities of mulberry leaf extracted with different concentrations of EtOH were investigated. Total phenolic content and electron donating abilities of extract from 70% EtOH were the highest. Extracts obtained from EtOH-water mixture were shown to be significantly higher superoxide dismutase (SOD)-like activities than other treatment (p<0.05). Angiotensin-converting enzyme (ACE) inhibition was the greatest at 50% EtOH concentration (p<0.05). The extracts from 30-70% EtOH exhibited higher ferric reducing ability of plasma (FRAP) value than rest of the concentration (p<0.05). In case of nitrite scavenging activity, much higher scavenging activities were observed when the extraction was performed with EtOH or EtOH-water mixture (p<0.05). The results indicate that concentration of EtOH as extraction solvents can affect the antioxidant activity of mulberry leaf, which may provide useful information on the optimal solvent conditions for the extraction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.153-160
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• 2013

The peel from seven types of citrus was extracted with 80% methanol, and their phenolic compound content, oxygen radical absorbance capacity (ORAC), inhibitory activities of nitric oxide (NO), and reactive oxygen species (ROS) production induced by LPS and t-BHP in LPS-activated RAW 264.7 cells were measured. Total phenolic content was high in Yungkyool, Cheonhyehyang, and Jinkyool (30.6, 30.2, and 28.2 mg GAE/g, respectively), while total flavonoid content was high in Yungkyool and Jinkyool (30.3 and 25.5 mg RE/g, respectively). ORAC was the highest at 1,076 mM TE/g in Yungkyool, followed by Cheonhyehyang (1,012), Jinkyool (984), and Hallabong (914). High inhibitory activity against NO production was shown in Cheonhyehyang, Yungkyool, and Jinkyool with $IC_{50}$ values of 215.3, 259.2, and 328.9 ${\mu}g/mL$, respectively. LPS-induced ROS production was inhibited by 16.4% and 12.8% in Hallabong and Jinkyool, while t-BHP-induced ROS production was inhibited by 28.7%, 26.1%, and 26.6% in Jinkyool, Hallabong, and Cheonhyehyang, respectively. Correlation coefficients between total phenolic, total flavonoid content, and ORAC were 0.884 and 0.855. Inhibitory activity against NO production showed higher correlation with total phenolic content than total flavonoid content. It was concluded that citrus peels had potent antioxidant activities and could be used as natural antioxidants in the food and pharmaceutical industries.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.73-77
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• 2005

Contents of isoflavone, phenolic acids, tocopherol, and anthocyanin in black soybean (Glycine max) were measured by HPLC. To compare antioxidative activities of main black soybean components, antioxidative effects of the same levels of commercial standard components were measured by Trolox equivalent antioxidant capacity assay (TEAC). Most effective component was gentisic acid followed by anthocyanin, p-coumaric acid, ferulic acid, genistein, syringic acid, and daidzein. TEAC assay results revealed genistein in isoflavone, gentisic acid in phenolic acids, p-tocopherol in tocopherol, and anthocyanin showed highest antioxidative and synergistic acitivities, with anthocyanin showing strongest synergy effect.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.3
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• pp.251-259
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• 1987

Humic acids extracted from decomposing plant residues were characterized by infrared(IR) spectra. The IR spectra were further interpreted by chemical analyses for oxygen-containing functional groups such as carboxyl, phenolic, alcoholic, carbonyl, and quinionic groups. 1. The IR spectra obtained in this study were divied into three categories: spectra of humic acids from grain crop straws of rice, barley, wheat and rye produced Type I, while that from wild grass hay yielded Type II, and those from forest tree litter of the deciduous and conifers were led to give Type III. 2. There were no significant changes in the absorption bands observed among humic acids extracted at various stages of decomposition of a given Plant material. 3. The absorption band at about $3,430cm^{-1}$ represents the presence of hydrogen-bonded hydroxyl groups, phenolic-OH groups being the major component. 4. A close relationship was found between the total acidity and the content of phenolic-OH groups of humic acids. The content of carboxyl groups maintains a direct relationship with the content of total hydroxyl groups, and such a close relationship also exists between the content of alcoholic hydroxyls and that of total hydroxyl groups. 5. Overlapping of the absorption bands of carbonyl groups and quinones renders it difficult to make differentiation between the two. 6. A variety of non-armoatic cyclic hydrocarbons appears to be a structural component as evidenced by a sharp absorption peak near $995-1000cm^{-1}$.