• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.8-14
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• 2002

Pseudomonas sp. S-47 is capable of degrading 4-chlorobenzoate to produce 5-chloro-2-hydroxymuconic semialdehyde (5C-2HMS) by the enzymes encoding by xylXYZLTE cluster. In this study, the resulting 5C-2HMS was confirmed to be transformed to 5-chloro-2-hydroxymuconic acid (5C-2HMA) by 5C-2HMS dehydrogenase. The xylG gene encoding 5C-2HMS dehydrogenase was cloned from the chromosomal DNA of strain S-47. The nucleotide sequence of xylG showed to be composed of 1,600 base pairs with ATG initiation and TGA termination codons. A deduced amino acid sequence of the 5C-2HMS dehydrogenase (XylG) exhibited 98％, 93％, and 89％ identity with those of the dehydrogenases from P. putida mt-2, P. putida G7, and Pseudomonas sp. CF600, respectively.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.333-340
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• 1997

An analytical method was developed to determine residues of haloxyfop-R and its methyl ester in soils and soybeans using gas-liquid chromatography (GLC) with electron capture detector (ECD). Soil or soybean sample was acidified and extracted with acetone. The extract was then subjected to ion-associated partition to individually separate haloxyfop-R and the neutral methyl ester. One phase containing haloxyfop-R was methylated with $BF_3$/methanol, partitioned to n-hexane and analyzed by GLC/ECD. The other phase containing the methyl ester was further purified by Florisil column chromatography prior to GLC determination. No cross contamination was found between two phases containing each of the acid and methyl ester, thus two compounds can be separately determined as the identical haloxyfop-R-methyl. Overall recoveries of haloxyfop-R from fortified samples averaged 88.2${\pm}$3.9% (n=12) and 88.3${\pm}$4.0% (n=6) for soils and soybeans respectively, and those of haloxyfop-R-methyl showed mean values of 89.2${\pm}$4.0% (n=12) and 85.6${\pm}$5.6% (n=6). Detection limits of both haloxyfop-R and its methyl esterwere 0.005㎎/㎏ and 0.01㎎/㎏ for soil and soybean samples respectively.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.22-31
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• 2015

This study was carried out to monitor the current status of pesticide residues in selling agricultural products via online and assessed their safety in 2014. A total of 124 samples were purchased six times from March to August 2014 twenty online shopping malls randomly. These samples were analysed 208 pesticides by multiresidue method using a GC-ECD/NPD and a LC-MS/MS and confirmed by a GC-MSD. As a result of analysis, residual pesticides samples were 11 (8.9%) such as leek, young radish, welsh onion etc, of which 2 samples (1.6%) such as sesame bud (Chlorothalonil), artemisia (Chlorpyrifos) were violated Korea Maximum Residue limits (MRLs). 11 kinds of pesticides (19 times) were detected in 11 samples. Risk assessment evaluated human health exposure with the ratio of EDI (Estimated daily intake) to ADI (Acceptable daily intake) of pesticides detected. %ADI (the ratios of EDI to ADI) were 0.04~95.70% and some samples represented a fairly dangerous levels. In particular, Chlorothalonil in the sesame bud was shown as a significant risk close to 100% of %ADI. Accordingly, it is recommended to strengthen a safety check on agricultural products in online sales.

• Resources Recycling
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• v.8 no.5
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• pp.34-43
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• 1999

An elecmc arc cracking reaclor is developed for the productiol~o f ieusuble fuel gas by the thennal destruction of waste oil. The churaclensucs of product gas and ~esiduesf rom arc crachng of wnste lubr~cat~nogil are sludird. Thc product gas is mainly coruposcd of hydrogen 135-4076), acetylene (13-4076), ethylene 13-476) and olher hgdrocnrbons. The contenr of carbon monomde, one or the main product in a conventional low-temperature Lhennal cracking umt, 1s very slnvll in lhis atc cracking expcnmcnt. Total calocctic wlue of product gas shows 11,000-13.000 kcizlkg, which is hiph cnough to use as a ~ L I I I Cga~ s . and the concentralions oC loxic gases arc well below the rcguliltury emission critena The GCIMS analysis of llquld-phase residues shows that the high rnalccular welgllt hydrocilrbons in the waste oil arc cracked into the low malecular weight hydrocarbons snd hydroem,. The dehydrogcnntion is found lo be Lhe main cracking rcacuon due lo the high temperalure ~ ~ ~ d ubcyc edle ctric arc. The average parucle size of soot as the solid-phase residue is 10 3 wm, and the conlents of cabon a ~ hdea vy metals are abovc 60% and under 0.01 ppm, respecttrely. Thc utllizvtion or sool, as industl-id1 rcsource seems lo he reasible aIter refimng.

• Resources Recycling
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• v.25 no.1
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• pp.3-9
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• 2016

The leaching behavior of gold from waste CPU chip using Iodide/Iodine solution was studied. The direct leaching of gold with Iodide/Iodine solution for CPU chip under the size of 150 mesh showed leaching ratio of 20%. It was assumed that the copper film was produced on the gold particle during grinding process and the copper film prevents lodine/Iodide solution from contacting with leachable gold. Meanwhile, the extraction of gold was improved to 90% by pretreatment process with $HNO_3$ solution. In order to explain the result, EDS and ICP analysis for the leaching residue were conducted. It was found that the copper coated on the surface of the gold particle was removed about 80% by $HNO_3$, resulting in the increment of gold leaching rate.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.2
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• pp.301-312
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• 1996

This study was performed to search a optimal analyzing method of cadmium in whole-blood. Cadmium was determined by graphite furnace atomic absorption spectrometry(GFAAS). We investigated the effect of ashing temperature on the absorbance of cadmium in a simple dilution(ten-fold) method with triton X-100 and matrix modifier methods treated with $NH_4H_2PO_4$(1 and 3%) and $Pd(NO_3)_2$(0.00l and 0.005%) as matrix modifier. We also compared the reported reference values of standard blood with values resulted from optimal analyzing conditions of this study. In case of a simple dilution method, when ashing temperature was set at $450^{\circ}C$, the absorbance of sample and background were $0.334{\pm}0.012$ and $1.382{\pm}0.245$, respectively. Background level was higher than the value(0.8) that can be corrected by $D_2$ background correction method. As ashing temperature was rised to $500^{\circ}C$, the absorbance of sample and background were $0.178{\pm}0.008$ and $0.711{\pm}0.223$ respectively. The higher ashing temperature($450^{\circ}C-650^{\circ}C$) was, the lower the absorbance of sample was. In case of a matrix modifier method with $NH_4H_2PO_4$(1 and 3%), when ashing temperature was rised from $500^{\circ}C$ to $650^{\circ}C$, the absorbance of sample slightly changed. The absorbances of sample at $600^{\circ}C$ were $0.230{\pm}0.017$ and $0.137{\pm}0.012$, respectively. These values were larger than that of simple dilution method. But the absorbance of background was higher than the level that can be corrected by $D_2$ method. In case of a matrix modifier method with $Pd(NO_3)_2$(0.001 and 0.005%), the absorbance of sample and background were higher than those of other methods and were stable and reproducible. When ashing temperature was over $550^{\circ}C$, the absorbance of sample was significantly decreased. In case of 0.005% $Pd(NO_3)_2$ carbon residue remained in graphite tube affected the absorbance of sample and background. From these results, We propose that in case of a simple dilution(ten-fold) method with triton X-100 ashing temperature must be maintained below $400^{\circ}C$. In order to diminish the absorbance of background, the alternative method is attenuation of injection volume or multiplication of dilution ratio. We recommend $Pd(NO_3)_2$ than $NH_4H_2PO_4$ as a matrix modifier. In case of a matrix modifier method with $Pd(NO_3)_2$ ashing temperature might be maintained below $550^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.90-96
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• 2013

The anti-obesity effect of ethanol xtract and their fractions from Rumex Crispus L. on the differentiation of 3T3-L1 pre-adipocytes to adipocytes was investigated by suppressing adipocyte differentiation and lipid accumulation with Oil red O assay, western blot and real-time PCR analysis. Ethyl acetate fraction of Rumex crispus L. significantly inhibited adipocyte differentiation when treated during the adipocyte differentiation process, as assessed by measuring fat accumulation using Oil red O staining. In inducing differentiation of 3T3-L1 preadipocytes in the presence of an adipogenic cocktail, isobutylmethylxanthine (IBMX), dexamethasone- and insulin-along with ethyl acetate fraction residue processing treatment significantly decreased protein expression of obesity-related proteins, such as peroxisome-proliferators-activated-receptor-${\gamma}$ ($PPAR{\gamma}$) and CCAAT enhancer-binding-proteins ${\alpha}$ ($C/EBP{\alpha}$). These results indicate that ethyl acetate fraction of Rumex crispus L. is the most effective candidate for preventing obesity. However further studies will be needed to identify the active compounds that confer the anti-obesity activity of ethyl acetate fraction from Rumex crispus L.

• Journal of Food Hygiene and Safety
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• v.32 no.2
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• pp.141-146
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• 2017

A rapid and precise method using LC-MS/MS was developed for carbendazim analysis in agricultural products. This compound was extracted with acetonitrile from agricultural products and cleaned up by solid-phase extraction procedure. The limit of detection and quantification were 0.001 mg/kg and 0.004 mg/kg, respectively. The mean recoveries and precision from 4 agricultural products, soybean sprout and mungbean sprout were in the range of 83.3-86.4% and 0.2-3.0% spiked at 1.0 mg/kg and those were in the range of 77.3-90.1% and 1.3-3.8% spiked at 0.02 mg/kg. The present method is faster and more precise compared with the multi-residue method of Korean Food Code. Therefore, we conclude that this method is suitable for carbendazim determination in a wide range of agricultural products.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1252-1257
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• 2011

Number of crop residues generated at large amount in agriculture can be utilized as substrate in methane production by anaerobic digestion. Greenhouse vegetable crop cultivation that adopting intensive agricultural system require the heating energy during winter season, meanwhile produce waste biomass source for the methane production. The purpose of this study was to investigate the methane production potential of greenhouse vegetable crop residues and to estimate material and energy yield in greenhouse system. Cucumber, tomato, and paprika as greenhouse vegetable crop were used in this study. Fallen fruit, leaf, and stem residues were collected at harvesting period from the farmhouses (Anseong, Gyeonggi, Korea) adopting an intensive greenhouse cultivation system. Also the amount of fallen vegetables and plant residues, and planting density of each vegetable crop were investigated. Chemical properties of vegetable waste biomass were determined, and theoretical methane potentials were calculated using Buswell's formula from the element analysis data. Also, BMP (Biochemical methane potential) assay was carried out for each vegetable waste biomass in mesophilic temperature ($38^{\circ}C$). Theoretical methane potential ($B_{th}$) and Ultimate methane potential ($B_u$) off stem, leaf, and fallen fruit in vegetable residues showed the range of $0.352{\sim}0.485Nm^3\;kg^{-1}VS_{added}$ and $0.136{\sim}0.354Nm^3\;kg^{-1}VS_{added}$ respectively. The biomass yields of residues of tomato, cucumber, and paprika were 28.3, 30.5, and $21.5Mg\;ha^{-1}$ respectively. The methane yields of tomato, cucumber, and paprika residues showed 645.0, 782.5, and $686.8Nm^3\;ha^{-1}$. Methane yield ($Nm^3\;ha^{-1}$) of crop residue may be highly influenced by biomass yield which is mainly affected by planting density.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.335-344
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• 2021

BACKGROUND: Cyantraniliprole is a systemic diamide insecticide that has been used to control lepidopteran pests in agriculture. Cyantraniliprole has become an issue due to its potentiality of unexpectable contamination in rotational crop cultivation. Thus, studies on the evaluation of cyantraniliprole translocated from soil into rotational crops are required. METHODS AND RESULTS: Cyantraniliprole was treated at a yearly maximum application level onto bare soil under greenhouse conditions in two geographically different regions. Lettuce was transplanted and spinach and radish were sown onto the soil 30 and 60 days-plant back intervals (PBIs) after cyantraniliprole treatment. The QuEChERS method was modified and coupled with LC/MS/MS analysis to determine the residues of cyantraniliprole in soil and plant samples. The methods for sample preparation and instrumental conditions were validated to meet the criteria of Codex guidelines and were successful to determine cyantraniliprole quantitatively and qualitatively in the samples. Cyantraniliprole residues in lettuce samples were 0.01 mg/kg for PBI 60 and 0.02 mg/kg for PBI 30, respectively. The residues in spinach samples were 0.01 mg/kg for PBI 60 and 0.01~0.02 mg/kg for PBI 30, respectively. Less than limit of the quantitation (LOQ) level (0.01 mg/kg) of cyantraniliprole was observed in radish samples. The residues in the plant samples were found as the levels less than maximum residue limit (MRL) for leafy and root vegetables. CONCLUSION(S): This study suggests PBI 30~60 days for rotational cultivation of lettuce, spinach and radish in greenhouse soil treated with cyantraniliprole at a yearly maximum application level.