• Title/Summary/Keyword: residue analysis

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Understanding Ancient Human Subsistence through the Application of Organic Residue Analysis on Prehistoric Pottery Vessels from the Korean Peninsula

  • Kwak, Seungki;Kim, Gyeongtaek
    • Journal of Conservation Science
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    • v.36 no.4
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    • pp.244-254
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    • 2020
  • This study investigates prehistoric human subsistence and pottery use on the Korean peninsula through the organic residue analysis of archaeological potsherds. Ancient human subsistence is one of the core topics in Korean archaeology. However, due to the high acidity of sediments, which prevents the long-term preservation of organic remains, archaeologists have been short of critical information on how these early prehistoric dwellers lived. Ceramic vessels can contain well-preserved lipids originating from past culinary practices. For a better understanding of human subsistence on the prehistoric Korean peninsula, food-processing behaviors were reconstructed by analyzing ancient lipids extracted from a pottery matrix. The potsherd samples used in the analysis in this paper were collected from major prehistoric habitation sites. The results show that subsistence strategies differed according to both location and time period and reveal how organic residue analysis can contribute to a better understanding of prehistoric human subsistence strategies.

Quantitative Analysis of Soluble Residues by Correction of Starch Content in Paperboard Grade (전분 함량 보정을 통한 판지류의 가용성 잔류물질 정량 분석)

  • Lim, Chae-Hoon;Park, Joung-Yoon;Lee, Tai-Ju;Um, Gi Jeung;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.45 no.6
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    • pp.78-87
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    • 2013
  • Even though the notice No. 2010-11 of the Ministry of Food and Drug Safety Administration that has been applied to analyze the content of the water soluble residue eluted from multi-layer paperboard was abolished in 2011, its application for the analysis on evaporation residue is still valid. There are very high possibilities that the noticed existing method gives the misleading result on the evaporation residue due to the water soluble starch eluted from the multi-layer paperboard. The quantitative analysis on water-soluble residue with starch content correction has been carried in the study using UV/Vis spectroscopy and HPLC. The UV/Vis spectroscopy absorbance analysis showed the large amount of the oxidized starch obtained from the aqueous residue eluted out of the multi-layer paperboard after the iodine, ${\alpha}$-amylase reaction, and starch hydrolysis. The residual content decreased by the correction through the enzyme hydrolysis.

Immune Responses in Broiler Chicks Fed Propolis Extraction Residue-supplemented Diets

  • Eyng, C.;Murakami, A.E.;Santos, T.C.;Silveira, T.G.V.;Pedroso, R.B.;Lourenco, D.A.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.1
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    • pp.135-142
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    • 2015
  • This study was conducted to evaluate the effect of inclusion of propolis extraction residue in the feed of broilers from 1 to 21 d of age on phagocytic activity of macrophages, cutaneous basophil hypersensitivity response to phytohemagglutinin, antibody production against Newcastle disease, lymphoid organ weight and hematological profile and to determine the optimal level of inclusion. 120 chicks, reared in metabolism cages until 21 days of age, were distributed in a completely randomized design, with five treatments (0%, 1%, 2%, 3%, and 4% of propolis residue) and six replications. The relative weight of thymus and monocyte percentage were affected by propolis residue, with a quadratic response (p<0.05) and lowest values estimated at 2.38% and 2.49%, respectively. Changes in relative weight of cloacal bursa and spleen, percentage of lymphocyte, heterophil, basophil, eosinophil, and heterophil:lymphocyte ratio, antibody production against Newcastle disease, phagocytic activity of macrophages and the average number of phagocytosed erythrocytes were not observed. The nitric oxide production with regard to positive control (macrophages+erythrocytes) decreased linearly (p<0.05) with increased doses of propolis residue. The remaining variables of nitric oxide production (negative control - macrophages, and difference between the controls) were not affected by propolis residue. The cutaneous basophil hypersensitivity response to phytohemagglutinin as determined by the increase in interdigital skin thickness exhibited a quadratic response (p<0.05), which predicted a lower reaction response at a dose of 2.60% of propolis residue and highest reaction response after 43.05 hours of phytohemagglutinin injection. The inclusion of 1% to 4% of propolis extraction residue in broiler diets from 1 to 21 days of age was not able to improve the immune parameters, despite the modest changes in the relative weight in thymus, blood monocyte percentage, nitric oxide concentration, and interdigital reaction to phytohemagglutinin.

Optimizing Recipes of Korean-style Cut Noodles with Anchovy Engraulis japonicus Soup Base Residue Powder (멸치(Engraulis japonicus) 잔사 분말을 첨가한 칼국수의 최적화)

  • Lee, So-Yeon;Ryu, Hong-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.5
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    • pp.545-555
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    • 2014
  • To develop Korean-style cut noodles with enhanced protein and calcium levels, we manipulated the ratio of dried anchovy Engraulis japonicus soup base residue powder to wheat flour, using a response surface methodology based on trained panel trials to determine the optimum ratio. Texture analysis and nutritional evaluation were also performed on cut noodles containing dried anchovy soup base residue (CNAR). Higher umami taste and springiness, and lower fishy flavor were strongly correlated with overall acceptability. The optimal CNAR formulation consisted of wheat flour (96.02 g), anchovy residue powder (2.67 g), and water (50.64 mL). CNAR had lower gumminess and adhesiveness (P<0.001), but higher springiness, cohesiveness (P<0.001), and chewiness (P<0.05), than the control (original wheat flour cut noodles). The addition of anchovy soup base residue elevated protein, lipid, and ash levels relative to the control. Color values decreased with increasing residue powder content. In vitro protein and starch digestibility of CNAR were lower than in the control (P<0.001). CNAR yielded significantly higher total free amino acid content than the control (P<0.01), leading to CNAR's improved palatability. Dried anchovy soup base residue can be used in wheat flour cut noodles to improve nutrition, sensory acceptability, and profitability.

Study for Residue Analysis of Fluxametamid in Agricultural Commodities

  • Kim, Ji Young;Choi, Yoon Ju;Kim, Jong Soo;Kim, Do Hoon;Do, Jung Ah;Jung, Yong Hyun;Lee, Kang Bong;Kim, Hyochin
    • Korean Journal of Environmental Agriculture
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    • v.38 no.1
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    • pp.1-9
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    • 2019
  • BACKGROUND: Accurate and simple analytical method determining Fluxametamid residue was necessary in various food matrices. Additionally, fulfilment of the international guideline of Codex (Codex Alimentarius Commission CAC/GL 40) was required for the analytical method. In this study, we developed Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) method to determine the Fluxametamid residue in foods. METHODS AND RESULTS: Fluxametamid was extracted with acetonitrile, partitioned and concentrated with dichloromethane. To remove the interferences, silica SPE cartridge was used before LC-MS/MS (Liquid Chromatography-Tandem Mass Spectrometry) analysis with $C_{18}$ column. Five agricultural commodities (mandarin, potato, soybean, hulled rice, and red pepper) were used as a group representative to verify the method. The liner matrix-matched calibration curves were confirmed with coefficient of determination ($r^2$) greater than 0.99 at calibration range of 0.001-0.25 mg/kg. The limits of detection and quantification were 0.001 and 0.005 mg/kg, respectively. Mean average accuracies were shown to be 82.24-115.27%. The precision was also shown to be less than 10% for all five samples. CONCLUSION: The method investigated in this study was suitable to the Codex guideline for the residue analysis. Thus, this method can be useful for determining the residue in various food matrices as routine analysis.

Study for Residue Analysis of Pinoxaden in Agricultural Commodities

  • Kim, Ji Young;Yoon, Eun Kyung;Kim, Jong Soo;Seong, Nu Ri;Yun, Sang Soon;Jung, Yong Hyun;Oh, Jae Ho;Kim, Hyochin
    • Korean Journal of Environmental Agriculture
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    • v.38 no.4
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    • pp.321-331
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    • 2019
  • BACKGROUND: Pinoxaden is the phenylpyrazoline herbicide developed by Syngenta Crop Protection, Inc. and marketed on 2006. The maximum residue levels for wheat and barley were set by import tolerance. Thus, Ministry of Food and Drug Safety (MFDS) official analytical method determining Pinoxaden residue was necessary in various food matrixes. Satisfaction of international guideline of CODEX (Codex Alimentarius Commission CAC/GL 40) and National Institute of Food and Drug Safety Evaluation-MFDS (2017) are additional pre-requirements for analytical method. In this study, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was investigated to analyze residue of Pinoxaden (M4), which is defined as pesticide residue in Korea, in foods. METHODS AND RESULTS: Pinoxaden (M4) was extracted followed by acid digestion (2hr reflux with 1N HCl) and pH adjusting (pH 4-5 with 3% ammonium solution). To remove oil, additional clean-up step with hexane saturated with acetonitrile was required to high oil contained sample before purification. HLB cartridge and nylon syringe filter were used for purification. Then, samples were analyzed by LC-MS/MS using reserve phase column C18. Five agricultural group representative commodities (mandarin, potato, soybean, hulled rice, and red pepper) were used to verify the method in this study. The liner matrix-matched calibration curves were confirmed with coefficient of determination (r2) > 0.99 at calibration range 0.002-0.2 mg/kg. The limits of detection and quantitation were 0.004 and 0.01 mg/kg, respectively, which were suitable to apply Positive List System (PLS). Mean average accuracies of pinoxaden (M4) were shown to be 74.0-105.7%. The precision of pinoxaden and its metabolites were also shown less than 14.5% for all five samples. CONCLUSION: The method investigated in this study was suitable to CODEX (CAC/GL 40) and National Institute of Food and Drug Safety Evaluation-MFDS (2017) guideline for residue analysis. Thus, this method can be useful for determining the residue in various food matrixes in routine analysis.

Analysis of Variability Factors in Establishing Pesticide Residue Limits on Food Crops (농산물중 농약잔류 허용기준 설정시의 변이계수 분석)

  • Lee, Mi-Gyung;Lee, Su-Rae
    • Korean Journal of Food Science and Technology
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    • v.37 no.3
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    • pp.492-497
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    • 2005
  • In establishing legal limits of pesticide residues, various default values are employed to compensate for unavoidable variability in data. Because permissible errors in residue analysis reach ${\pm}30-40%$ RSD, maximum residue limits (MRLs) follow geometric progression. According to 5-yr period JMPR reports, variability factor (ratio of highest to median values) in field residue trials was 3.8-fold in 486 crop-pesticide combinations and round-up effort from highest residue to MRL was 1.5-fold, whereas regulatory margin (ratio of MRL to highest residue) used in Korea was 4.8-fold in 822 crop-pesticide combinations; Korean MRLs will be set at higher levels as compared with Codex limits if these margins are employed. Validation studies to compare and harmonize Korean and Codex MRLs of pesticide residues on food crops should be undertaken.

A spectral domain analysis of microstrip lines using a residue theorem (유수정리를 이용한 마이크로스트립 선로의 스펙트럼 영역 해석)

  • 문병귀;진경수;박병우
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.1
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    • pp.8-15
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    • 1998
  • An analysis of the microstripline is started as an assumption of the axial & transveral current distribution. Applying the boundary conditions to the scalar wave equations of a electric & magnetic potential, the two simultaneous coupled integral equations are produced. The electronmagnetic fields in microstrip line can be obtained by solving these two coupled integral equaltion. In general, either a numerical analysis method or a Galerkin method was used to solve them. In this paper, a residue theorem is proposed to solve them. The electromagnetic fields are expressed as integral equations for LSE and LSM mode in the spectral domain. Applying a residue theorem to the Fourier transformed equation and Fourier inverse transformed equation which is necessary for interchanging the space domain and the spectral domain, the electromagnetic fields are expressed as algebraic equations whichare relatively easier to handle. the distributions of the electromagnetic field are shown at the range of -5w/2.leq.x.leq.5w/2, 0.lep.y.leq.4h for z=0. It agrees well with the results of the Quasi-TEM mode analysis.

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Effects of Short-Term Soil Tillage Management on Activity and Community Structure of Denitrifiers under Double-Cropping Rice Field

  • Tang, Haiming;Li, Chao;Cheng, Kaikai;Shi, Lihong;Wen, Li;Xiao, Xiaoping;Xu, Yilan;Li, Weiyan;Wang, Ke
    • Journal of Microbiology and Biotechnology
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    • v.30 no.11
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    • pp.1688-1696
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    • 2020
  • Soil physical and chemical characteristics, soil potential denitrification rates (PDR), community composition and nirK-, nirS- and nosZ-encoding denitrifiers were studied by using MiSeq sequencing, quantitative polymerase chain reaction (qPCR), and terminal restriction fragment polymorphism (T-RFLP) technologies base on short-term (5-year) tillage field experiment. The experiment included four tillage treatments: conventional tillage with crop residue incorporation (CT), rotary tillage with crop residue incorporation (RT), no-tillage with crop residue retention (NT), and rotary tillage with crop residue removed as control (RTO). The results indicated that soil organic carbon, total nitrogen and NH4+-N contents were increased with CT, RT and NT treatments. Compared with RTO treatment, the copies number of nirK, nirS and nosZ in paddy soil with CT, RT and NT treatments were significantly increased. The principal coordinate analysis indicated that tillage management and crop residue returning management were the most and the second important factors for the change of denitrifying bacteria community, respectively. Meanwhile, this study indicated that activity and community composition of denitrifiers with CT, RT and NT treatments were increased, compared with RTO treatment. This result showed that nirK, nirS and nosZ-type denitrifiers communities in crop residue applied soil had higher species diversity compared with crop residue removed soil, and denitrifying bacteria community composition were dominated by Gammaproteobacteria, Deltaproteobacteria, and Betaproteobacteria. Therefore, it is a beneficial practice to increase soil PDR level, abundance and community composition of nitrogen-functional soil microorganism by combined application of tillage with crop residue management.

Residues and Exposure Assessment of Carbendazim in Chamnamul on Field Trials for Revising Maximum Residue Limit in Korea (생산단계 참나물의 Carbendazim 잔류특성에 따른 노출평가 및 농약 잔류허용기준 개선)

  • Chang, Hee-Ra;Gwak, Hye-Min
    • Korean Journal of Environmental Agriculture
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    • v.41 no.3
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    • pp.153-157
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    • 2022
  • BACKGROUND: The residue dissipation pattern of pesticides for agricultural products during the pre-harvest period after the final application is important to prevent the maximum residue limit (MRL) violations in domestic and export markets. The MRL violations of carbendazim are observed more often in chamnamul by pesticide residue management surveys by the Ministry of Food and Drug Safety. The residue level at the pre-harvest interval (PHI) and the residue dissipation constant from the critical good agricultural practice (cGAP) trials could be estimated to meet the MRL and pose a health risk to consumers. METHODS AND RESULTS: Chamnamuls were harvested at 0, 1, 3, 5, 7, 10, and 14 days after application of carbendazim in accordance with critical GAP. The residue analysis in chamnanul was performed by HPLC-DAD with the C18 column. The limit of quantitation of carbendazim was 0.04 mg/kg, and the recoveries were 74.4 - 95.8% at the two spiked levels (LOQ and 10LOQ) of carbendazim. The dissipation rates in chamnamul were calculated from the residues at the sampling days by statistical method at a 95% confidence level. The biological half-lives of residual carbendazim in the field trials 1 and 2 were 4.9 and 4.4 days, respectively. CONCLUSION(S): In this dissipation study, the residue concentrations at the recommended PHI were higher than the established MRL in Korea. Therefore, the MRL is proposed based on the residue data sets from the trials conducted at the same cGAP and the dietary exposure assessment.