• Korean Journal of Environmental Agriculture
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• v.5 no.2
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• pp.113-118
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• 1986

After selecting four places in the main shellfish habitat, 118 items of the sample were collected in the mud flat from August to October in 1983, in order to analyze organochlorine pesticide residues by a gas chromatograph equipped with an electron capture detector. The results obtained were summarized as follows; ${\alpha}-BHC,\;{\gamma}-BHC\;&\;PCNB,\;heptachlor,\;{\gamma}-endosulfan,\;{\beta}-endosulfan,$ p, p'-DDE, dieldrin, o, p'-DDT and p, p'-DDT were detected in the range from 2 to 98 percent and their levels of mean residues ranged from trace to 0.041ppm, in the order of ${\gamma}-BHC\;&\;PCNB,\;{\alpha}-BHC,\;heptachlor{\approx}{\alpha}-endosulfan{\approx}p, p`-DDE{\approx}dieldrin{\approx}{\beta}-endosulfan{\approx}$o, p'-DDT, and p, p'-DDT. The mean of total residues in regions was Kangjin(0.058ppm), Kwangyang(0.080ppm), Yoch'on (0.016ppm), and Yonggwang(0.75ppm). ${\gamma}-BHC\;&\;PCNB$ peak were separated by column packed with DC-200. PCNB was identified by making a PCA(pentachloroaniline), the reduced derivative of PCNB, and this confirmed that PCNB residues were detected in the soil sample.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.164-168
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• 2005

An experimental design has been used to optimize the analysis of volatile component from fresh ginseng using solvent free solid injector (SFSI). The analysis were performed at three different sample preparing methods (fresh, oven drying and freezed drying), different injector port temperatures (100, 150, 200, 250 and $300^{\circ}C$) and different preheating time (3, 5, 7, 10 and 15 min) according to the above experimental design. The optimum conditions from analytical results were fresh sample (sample preparing methods), $250^{\circ}C$ (injector temperature) and 10 min (preheating time). Ginsengs grown for six years at Gumsan were prepared for fresh, white and red ginsengs. These fresh, white and red singsengs were analyzed for their volatile components by GC/MS equipped with SFSI according to the above the optimum conditions. A total of thirty-three volatile components were identified in fresh ginseng by SFSI, thirty-six in white ginseng and thirty-eight in red ginseng. These results suggested that the SFSI method could be used for isolating volatile component in ginsengs.

• Korean Journal of Environmental Agriculture
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• v.11 no.1
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• pp.59-66
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• 1992

An enzyme immunoassay(EIA) was developed for the analysis of insecticide endosulfan and its degradation products. The sensitivity and specificity of the antibody produced were examined. Optimal conditions in the ELISA system for residue analysis were also discussed. A mixed suspension of endosulfan-hemocyanin conjugate(ES-KLH) 1.1 mg/ml and Freund's adjuvant was injected subcutaneously to white rabbits and then collected antisera were tested for titers by indirect ELISA(1/24,000). Because of difficulties in the synthesis of endosulfan peroxidase conjugate, amine derivative of endosulfan-diol was synthesized and it showed 40% of conjugate yields(2mg/ml of conjugate). the highest sensitivity obtained enzyme-conjugate was a concentration of 200ng/ml. The detection limit of endosulfan in ELISA system was 5 ppb on the standard curve. In application of ELISA for residue analysis, the recoveries were really 100% both in the spiked soil and apple sample regardless of endosulfan concentration treated. On the other hand, chlorinated hydrocarbons of similar structure with endosulfan showed low cross-reactivity$(2.2%{\sim}29.2%).$

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.315-322
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• 2008

In this study, a simple, effective, and sensitive method has been developed for the quantitative residue analysis of cyhalofop-butyl and its metabolite cyhalofop acid in water and soil when kept under laboratory conditions. The content of cyholofop-butyl and cyhalofop acid in water and soil was analyzed by first purifying the compounds through liquid-liquid extraction and partitioning followed by Silica gel (adsorption) chromatography. Upon the completion of the purification step the residual levels were monitored through high-performance liquid chromatography (HPLC) using a UV absorbance detector. The recoveries of cyhalofop-butyl from three replicates spiked at two different concentrations ranged from 82.5 to 100.0% and from 66.7 to 97.9% in water and soil, respectively. The limit of detection and minimum detection level of cyhalofop-butyl in water and soil was 0.02 ppm and 10 ng, respectively. The recoveries of cyhalofop acid ranged from 80.7 to 104.8% in water and from 76.9 to 98.1 % in soil. The limit of detection of cyhalofop acid was 0.005 ppm in water and 0.01 ppm in soil, while the minimum detection level was 2 ng both in water and soil. The half-live of cyhalofop-butyl was 4.14 and 6.6 days in water and soil, respectively. The method was successfully applied to evaluate cyhalofop-butyl residues in water and soil applied aj. 30% emulsion, oil in water (EW) product.

• The Korean Journal of Pesticide Science
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• v.13 no.1
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• pp.28-38
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• 2009

An extrapolation of residue data of seven commonly used pesticides namely bifenthrin, chlorothalonil, cypermethrin, diazinon, fenvalerate, phenthoate and procymidone on a total of 22 minor crops has been carried out in an experimental field trial. The pesticides were applied to 11 leafy-, 5 root- and 6 stem-crops grown in the experimental green-house and the crops and plants were randomly collected at 1, 3, 5, 7 days after application. The average recoveries of applied pesticides were ranged from 72.0 to 117.0% in leafy crops, from 81.3 to 105.0% in stem crops and from 70.1 to 108.1% in the root-crops. Limits of detection (LODs) were 0.005-0.1 mg/kg in the leafy crops and 0.001-0.005 mg/kg in both the stem & root crops. Based on the results of residual dissipation pattern and their morphology, all crops were classified into high and low residual groups. The results showed that it might be possible to extrapolate residual data of stem-crops to root-crops within the same group. Crops that have currently no registered pesticide for use, would be possible to use the pesticides which are already been registered for the similar crops.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.209-215
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• 2009

This study was performed to produce the processing factors of pesticides in dried carrot. It is essential data for establishing the maximum residue limits (MRLs) of pesticides in dried carrot. The target pesticides were azinphos-methyl, chlorpyrifos, captan, endosulfan and triclorfon. These pesticides are included Korea's MRL list in carrot and USA's MRL list in dried foods. To infiltrate these pesticides up to each MRL level in carrot, the dipping test was performed in laboratory. Also, the supervised residue trial of the pesticide for carrot was conducted in the green house to recognize the field trial's tendency. In the dipping test in laboratory (including drying examination), the processing factors of the carrot at various concentrations and temperatures could be evaluated. In field test, the processing factors were 5.9 for azinphos-methyl, 1.7 for captan, 7.6 for chlorpyrifos, 6 for endosulfan, 0 for trichlorfon, respectively. The dipping test in laboratory on various kinds of conditions showed more precise processing factors than field trial. The processing factors obtained from the dipping test of carrot were 0~4.7 at the various concentration of the pesticides, and 0~6.7 at various drying temperature. The lower level processing factors were 0~0.6 for trichlorfon and the higher level were 3.0~5.8 for chlorpyrifos. The highest processing factor was 9.1 for captan.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.320-326
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• 2001

To obtain the basic data for preparing edible or biodegradable film, fish meal protein isolates (FMPI) were prepared through alkaline extraction. And FMPI's properties and the ester compounds permeability of FMPI film were measured. FMPI were extracted under various extracting time with 0.2 N NaOH solution at $60^{\circ}C$, Recovery ratios of FMPI extracted from fish meal were increased with extracting time increasing. Surface hydrophobicity of FMPI extracted for 1 hr showed highest value. Emulsifying activity index (EAI) was increased with the increasement of extracting time but its emulsifying stability index (ESI) showed an inverse results. Viscosity of FMPI solution showed the highest value at pH 2 but showed the lowest value at pH 4, The higher concentration of sorbitol as plasticizer showed the higher ethyl acetate permeability of FMPI film, Ethyl acetate permeability of FMPI films according to kind of plasticizers showed different degree and increased in order as follow: polyethylene glycol, glycerol and sorbitol. Ester compounds having the lower molecular weight showed the higher permeability. Increment of temperature increased the ethyl acetate permeability of FMPI film. FMPI haying higher surface hydrophobicity made FMPI film be higher tensile strength. On elongation of FMPI films, kinds of plasticizer were more effective than surface hydrophobicity of FMPI.

• Composites Research
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• v.27 no.6
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• pp.248-253
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• 2014

In this study, tapered double cantilever beam specimens are designed with the variable of angle to investigate the fracture property at the bonded surface of adjoint structure. These specimens are made with four kinds of models as the length of 200 mm and the slanted angles of bonded surfaces on specimens of $6^{\circ}$, $8^{\circ}$, $10^{\circ}$ and $12^{\circ}$. By investigating experiment and analysis result of these specimens, the maximum loads are happened at 120 N, 137 N, 154 N and 171 N respectively in cases of the specimens with slanted angles of $6^{\circ}$, $8^{\circ}$, $10^{\circ}$ and $12^{\circ}$. As the analysis result approach the experimental value, it is confirmed to have no much difference with the values of experiment and analysis. It is thought that the material property can be investigated effectively on shear behavior of the material composed of aluminum foam bonded with adhesive through simulation instead of experiment by applying this study method.

• Journal of Korean Society of Forest Science
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• v.80 no.3
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• pp.311-316
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• 1991

Butt-rot fungi were isolated from decayed portion in butt rotted larch trees[Larix leptolepis(Sieb. et Zucc.) Gord.]. From a total of 216 affected trees in 38 forests of five provinces, Sparassis crispa(Wulf. ex Fr.) Fr. was isolated with the highest frequency, i.e.. 28% of the total trees. Laetiporus sulphureus(Fr.) Bond. et Sing, with 19%, and Phaeolus schweinitzii(Fr.) Pat. with 8%. However, none of these fungi was isolated from 45% of the trees. Wood decaying abilities and interaction of four basidiomycetous and three non-basidiomyo:etous fungi isolated from butt rotted trees were investigated. The weight loss of larch wood blocks, when exposed to the culture of a fungus for six months, was 19.6% for P. schweinitzii, 10% for S. crispa, 8.2% for L. sulphurous, 5.1% for Coriolus hirsutus, and less than 4.4% for three non-basidiomycetous fungi. In incubation with combinations of the fungi, the wood decay activity of S. crispa, L. sulphurous and C. hirsutus was increased by the non-basidiomycetous fungi of Geotrichum candidacy, G. sp. and Verticillium sp., but that of P. schweinitzii was not.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.681-686
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• 2015

The purpose of this study was to measure total phenolic compounds as a measure of antioxidant activity as well as ${\alpha}$-amylase inhibitory and ${\alpha}$-glucosidase inhibitory activities as a measure of anti-diabetic efficacy in methanol extracts from 23 kinds of medicinal plants. Extracts of three medicinal plant species showing high total polyphenol contents were selected (Euonymus alatus stem, Taxus cuspidata fruit, and Eucommia ulmoides leaf). Extracts of six medicinal plant species showing over 60% DPPH radical scavenging activity were also selected [Eucommia ulmoides barks (80.10%), Lycium chinense roots (64.25%), Euonymus alatus stem (73.59%), Lespedeza cuneata (78.20%), Taxus cuspidata fruits (70.52%), and Tilia taquetii leaf and stem (67.81%)]. Regarding ${\alpha}$-glucosidase and ${\alpha}$-amylase inhibitory activities acarbose showing approximately 80% inhibitory activity was selected as a control group, and six species (Eucommia ulmoides heartwood, Eucommia ulmoides bark, Euonymus alatus stem, Dioscorea batatas, Coix lachryma-jobi, and Phaseolus radiatus) showed greater than 80% ${\alpha}$-glucosidase inhibitory activity. Extracts of nine medicinal plant. species showing over 80% ${\alpha}$-amylase inhibitory activity (Pueraria thunbergiana root, Eucommia ulmoides bark, Eucommia ulmoides leaf, Lycium chinense fruits, Euonymus alatus leaf and stem, Euonymus alatus stem, Sasa borealis whole, Dioscorea batatas leaf and stem, and Tilia taquetii leaf and stem). Based on these results, medicinal plants showing high antioxidant and antidiabetic activities can be used as fundamental products in developing new medicines, as well as functional foods to prevent adult disease.