• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.17-28
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• 2018

In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon material. Comparison study was also conducted by production of activated carbon from coconut shell (CCNS), Pinus, and Avicel, and each activated carbon was characterized by chemical composition, Raman spectroscopy, SEM analysis, and BET analysis. The amount of solid residue after thermogravimetric analysis of biomass samples at the final temperature of $750^{\circ}C$ was SAL > CCNS > Pinus > Avicel, which was the same as the order of activated carbon yields after catalytic activation. Specifically, SAL-derived activated carbon showed the highest value of carbon content (91.0%) and $I_d/I_g$ peak ratio (4.2), indicating that amorphous large aromatic structure layer was formed with high carbon fixation. In addition, the largest changes was observed in SAL with the maximum BET specific surface area and pore volume of $2341m^2/g$ and $1.270cm^3/g$, respectively. Furthermore, the adsorption test for three kinds of organic pollutants (phenol, 2,4-Dichlorophenoxyacetic acid, and carbofuran) were conducted, and an excellent adsorption capacity more than 90 mg/g for all activated carbon was determined using 100 ppm of the standard solution. Therefore, SAL, a condensed structure, can be used not only as a nanoporous carbon material with high specific surface area but also as a biosorbent applied to a carbon filter for remediation of organic pollutants in future.

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.137-143
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• 2002

Lyophilizate of immatured wax gourd extract was 3.1 %, matured wax gourd extract was 1.0%, and its main ingredient was sugar, which accounts for 89.7% in total residue. In matured wax gourd, pectin contents was 4.11 mg/ml, and in immatured wax gourd 4.43 mg/m1. In matured wax gourd sarcocarp, sugar contents was 0.1% of sucrose, 0.32% of glucose, 0.35% of fructose, the first unidentified sugar was 0.06% and the second was 0.04%, and all total 0.87%. In sarcocarp of immatured wax gourd, sucrose was 0.33%, glucose was 1.04%, frutcose was 1.12%, and the first unidentified sugar 0.18%, and the second was 0.l2, which total 2.79%. In matured wax gourd core, pH was 4.64, sarcocarp 4.94, immatured wax gourd core 4,96, sarcocarp 5.40. According to the organic acid analysis, in sarcocarp of matured wax gourd, citric acid of 0.409 was contained, magic acid 0.084, succnic acid 0.048%, in matured wax gourd core, citric acid was 0.648, magic acid 0.127, succinc acid 0.058%, in immatured wax gourd, citric acid 0.023, magic acid 0.219, succinic acid 0.298%, in immutured wax gourd, citric acid was 0.039, malic acid 0.350, succinic 0.224%. Fumaric acid was trace in all cases. Total organic acid in matured wax gourd core was 0.833, immatured wax gourd core was 0.624 and immatured wax gourd sarcocarp was 0.546, matured wax gourd sarcocarp was 0,541%. In inhibition rate to propionibacterium acnes, control was 0(ø, cm), wax gourd that was not heated was 2.6, and wax gourd which was heated was 2.5, concentrated by 1/5 was 1.9, wax gourd by 1/10 was 2.5, freezing dry was 2.3. Wax gourd which not heated on producing melanin in B-16 melanoma cell, the melanins forming unit was 15$\mu$1/m1 in addition of 0.01%, while that as a control was 29$\mu$1/m1.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.4
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• pp.247-256
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• 2013

In this study, alginate beads containing birnessite (Bir-AB), a highly reactive oxidative catalyst for the transformation of phenolic compounds, was prepared and its 1-naphthol (1-NP) removal efficiency was investigated in a batch test. Based on scanning electron microscopy image, it can be inferred that the alginate gel cluster acts as a bridge which bind the birnessite particles together. Kinetic experiment with Bir-AB of different mixing ratios of birnessite to alginate (Bir : AG=0.25 : 1~1 : 1 w/w) indicate that pseudo-first order kinetic constants, $k(hr^{-1})$ for the 1-NP removals increased about 1.5 times when the birnessite mixing ratio was doubled. The removals of 1-NP was found to be dependent on solution pH and the pesudo-first order rate constants were increased from 0.331 $hr^{-1}$ at pH 10 to 0.661 $hr^{-1}$ at pH 4. The analysis of total organic carbon for the reaction solutions showed that a higher removal of dissolved organic carbon was achieved with Bir-AB as compared to birnessite. HPLC chromatographic analysis of the methanol extract after reaction of 1-NP with Bir-AB suggest that the reaction products could be removed through incorporation into the aliginate beads as a bound residue. Mn ions produced from the oxidative transformation of 1-NP by birnessite were also removed by sorption to Bir-AB. The Bir-AB was recovered quantitatively by simple filtration and was reused twice without significant loss of the initial reactivity.

• Journal of Applied Biological Chemistry
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• v.52 no.4
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• pp.180-186
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• 2009

Whole plants of Vitex rotundifolia were extracted for 2 days with methylene chloride ($CH_2Cl_2$) followed by extraction of the residue for an additional 2 days. The same procedure was also applied using methanol (MeOH). The two crude extracts were combined and partitioned between $CH_2Cl_2$ and $H_2O$. The organic layer was further partitioned between n-hexane and 85% aq. MeOH, and the aqueous layer was also further fractionated with n-BuOH and $H_2O$, successively. From the 85% aq. MeOH fraction, one compound was isolated through the repeated HPLC. According to the results of physicochemical data including NMR and MS, the chemical structure of the compound was determined as artemetin (1). The antiproliferative effects of the crude extracts, fractions, and compound against HT1080, AGS, MCF-7 and HT-29 human cancer cells were compared with the control by using MTT assay. In the comparative analysis, the 85% aq. MeOH fraction exhibited the strongest antiproliferative effects on human cancer cell lines in a dose-dependent manner (p<0.05). In addition, exposure of compound 1 isolated from 85% aq. MeOH fraction led to strong antiproliferative effect in HT1080 cancer cell lines. These results suggest that the extracts and compound isolated from V. rotundifolia may be used as potential chemopreventive and chemotherapeutic agents.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.229-238
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• 1977

Sumithion and EPN residues on grapes, EPN and Diazinon on chinese cabbage, Parathion on peaches, Dimethoate on tomatoes, and EPN and Malathion on cucumber were analyzed in terms of 0, 3, 7, 14, 21 and 30 days after last application for the pesticides safty use. From the disappearance rate for various organo-phosphate insecticides on vegetables and fruit crops, following results are obtained. 1. On Chinese cabbage, Diazinon residues were 0.25~0.38p.p.m three weeks after one application, and EPN were 1.39~2.69p.p.m seven days after one application and 0.96~2.34p.p.m two weeks after twice application. 2. EPN residues on grapes were 1.09~1.80p.p.m seven days after one application and Sumithion were 0.17~0.53p.p.m fourteen days after one application. 3. On peaches, Parathion residues were 0.40~0.61p.p.m two weeks after last application. 4. Dimethoate residues on tomatoes were 0.141p.p.m seven days after four times application. 5. On cucumber, EPN residues were 2.11~2.14p.p.m three days after twice application, and Malathion were 0.46p.p.m 3 day after four times application but 0.062~0.025p.p.m three days after last application. 6. Rate of degradation of organo-phosphate chemicals is inversely related to half-life of its. 7. Minimum intervals between last treatment and harvest to prevent unsafty residues are as follows. 7 days for EPN with one application and 14 days with twice application on chinese cabbage, 3 days on cucumber and 7 days on grape, 14 days for parathion, 7 days for dimethoate on tomatoes, 0 to 3 days for Malathion on cucumber, 21 days for Sumithion on grape, 21 days on chinese cabbage for Diazinon.

• Journal of Food Hygiene and Safety
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• v.31 no.3
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• pp.186-193
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• 2016

An analytical method was developed for the determination of oxathiapiprolin in agricultural commodities. Oxathiapiprolin is a new oomycide (fungicide of piperidinyl thiazole isoxazoline class) which controls downy mildew in cucurbits caused by Pseudoperonospora cubensis (oomycete plant pathogen). Agricultural commodities were extracted with acetonitrile and partitioned with dichloromethane to remove the interference, adjusting pH between 9 and 10 by 1 N sodium hydroxide. After purification by silica SPE cartridge to clean up the interference of organic compounds, they were finally quantified by HPLC-UVD (high performance liquid chromatograph ultraviolet detector) using a wavelength at 260 nm and confirmed by LC-MS (liquid chromatograph mass spectrometer) in electro-spray ionization positive ion mode. The standard calibration curve was linear with coefficients of determination ($r^2$) 1.00 over the calibration ranges (0.025-2.5 mg/L). Recoveries were ranged between 86.7 to 112.7%, with relative standard deviations less than 10% at three concentration levels (LOQ, 10LOQ, and 50LOQ) performing five replicates. The overall results were determined and estimated according to the CODEX guidelines (CAC/GL40). The proposed method for determination of oxathiapiprolin residues in agricultural commodities can be used as an official method.

• The Korean Journal of Pesticide Science
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• v.3 no.2
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• pp.47-53
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• 1999

Photosensitizing activities of some photosensitizers (PS) for the artificial diminution of pesticide residues on horticultural crops were investigated. Five fungicides, iprodione, bitertanol, chlorothalonil, myclobutanil, and dichlofluanid were sprayed on apple and cucumber, followed by the application of each selected photosensitizer, and the samples were collected 0, 1, 3, 7, 15 days after the photosensitizer application and analyzed for the residual amounts. Of the 40 photosensitizers tested, six selected on the basis of the eliminating effect of pesticide residues were PS-1 (aromatic ketone), PS-2 (aromatic amine), PS-3 (quinone), PS-4 (inorganic compound), PS-5 (organic acid salt), and PS-6 (semiconductor photocatalyst). The residual amount of iprodione after 15 days of the application of PS-1 was 74% of that of the control. For bitertanol, the residual amount after 15 days of the application of PS-1 accounted for 78% of that of the control. The residual amounts of chlorothalonil after 1 day of the application of PS-1 and PS-2 accounted for 56 and 54% of those of the control, respectively. The residual amounts of iprodione on cucumber after 3 days of the application of the photosensitizers PS-1 and PS-2 were 44 and 67% of those of the untreated control, respectively. For myclobutanil, the residual amount after 15 days of the application of PS-6 accounted for 45% of that of the control. In case of dichlofluanid, the residual amount after 3 days of the application of PS-1 accounted for 44% of that of the control. Based on the results, PS-1 turned out to be the most promising photosensitizer for the accelerated photodegradation of the above fungicides on apple and cucumber.

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.30-38
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• 2008

Petroleum-based resin adhesives have extensively been used for the production of wood panels. However, with the increase of manufacturing cost and the environmental issue, such as the emission of volatile organic compounds, of the adhesive resins, it is necessary to be developed new adhesive systems. In this study, the potential of okara, which is a residue wasted from the production of tofu, for the development of bio-based adhesives was investigated. At first, the physical and chemical properties of okara were examined. After okara was hydrolyzed in acidic and/or alkaline solutions, okara-based adhesive resins were formulated with the mixtures of the okara hydrolyzates and phenol formaldehyde (PF) prepolymer. The adhesive resins were used for the fabrication of plywood panels, and then the adhesive strength and formaldehyde emission of the plywood panels were measured to examine the applicability of the resin adhesives for the production of plywood panels. The solids content and pH of the okara used in this study were around 20% and weak acidic state, respectively. In the analysis of its chemical composition, the content of carbohydrate was the highest, and followed by protein. The shear strengths of plywood fabricated with okara-based resin adhesives exceeded a minimum requirement of KS standard for ordinary plywood, but its wood failure did not reach the minimum requirement. In addition, the formaldehyde emissions of all plywood panels were higher than that of E1 specified in the KS standard. Based on these results, okara has the potential to be used as a raw material of environmentally friendly adhesive resin systems for the production of wood panels, but further researches - biological hydrolysis of okara and various formulations of PF prepolymer - are required to improve the adhesive strength and formaldehyde emission of okara-based resin adhesives.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.325-335
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• 1985

Biogas production from agricultural wastes were summarized as follows: 1. Biogas Generation Characteristics of Various Manures and Residues a. Gas yield from crop residues like rice straw, rice hull, corn stalk and coconut husk can be improved by addition of animal manures. b. Gas yield from coconut husk can be improved through aerobic fermentation for at least one week before loading in the digester. c. Gas yield from fresh rice straw is better than from pre-fermented one, whether alone or in combination with animal manures. d. Initial study has shown that fresh azolla can be substituted for animal manures in manurerice straw combinations and gas yield derived based on unit volatile solids loaded is actually better than for manure-residue combinations. e. Gas production is highly sensitive to substrate pH and becomes almost nil at a pH of below 6. 2. Effect of ambient conditions and other factors on biogas production in a house hold-size digester. a. Results showed that compaction of rice straw in straw-manure combination can reduce gas yield compared with loosely mixed straw. b. The effective gas production period extended to 70 days using freshly threshed rice straw and fresh cattle manure as feed material. c. Underground and above ground digesters with shade have relatively more stable substrate temperature than aboveground exposed digesters. This relative temperature instability may likely be the reason for lower gas yield for the exposed aboveground digester loaded with loose straw-cattle manure substrate, compared with the underground digester with the same substrate. 3. Economic Analysis a. Based on prevailing costs of fuel, materials, and labor in the Philippines, biogas produced from the household size system is cheaper than either LPG or kerosene. b. If other benefits like organic fertilizer, pollution control and convenience are considered, biogas will surely be the best alternative fuel source.