• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.946-950
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• 2014

Bacillus licheniformis was grown in minimal nutrient medium containing 1% (w/v) of distillers dried grain with soluble (DDGS), palm kernel meal (PKM), wheat bran (WB) or copra meal (CM), and the enzyme activity of endoglucanase, ${\beta}$-glucosidase, xylanase and reducing sugars was measured to investigate a possibility of using cost-effective agricultural residues in producing cellulolytic and hemicellulolytic enzymes. The CM gave the highest endoglucanase activity of 0.68 units/mL among added substrates at 48 h. CM yielded the highest titres of 0.58 units/ml of ${\beta}$-glucosidase, compared to 0.33, 0.23, and 0.16 units/mL by PKM, WB, and DDGS, respectively, at 72 h. Xylanase production was the highest (0.34 units/mL) when CM was added. The supernatant from fermentation of CM had the highest reducing sugars than other additional substrates at all intervals (0.10, 0.12, 0.10, and 0.11 mg/mL respectively). It is concluded that Bacillus licheniformis is capable of producing multiple cellulo- and hemicellololytic enzymes for bioethanol production using cost-effective agricultural residues, especially CM, as a sole nutrient source.

• Journal of Environmental Health Sciences
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• v.34 no.6
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• pp.433-438
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• 2008

Much of the increase in agricultural productivity over the past half century has been due to the control of the pests with synthetic pesticides. The use of these pesticides has caused environmental problems and public health concern. The guidelines of maximum residue levels of pesticides in agricultural products has been well documented but more careful monitoring of their residues is required. Pyrethorid class pesticides are dominant in modern agricultural industry but public health concerns have been recently considered. The major route of pesticide exposure is the diet and with improved surveillance of pyrethorid residues in agricultural products their exposure should be controlled and minimized. In suitable products with reduced matrix effects such as agricultural products, aqueous samples, fruits and vegetables the use of immunoassays for pyrethorid residue monitoring could satisfy this requirement. Immunoassays have several advantages, namely they are highly sensitive, selective and cost-effective and enable large-scale sample handling and analysis in the laboratory.

• Journal of Veterinary Science
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• v.25 no.1
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• pp.18.1-18.27
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• 2024

Mastitis is one of the most widespread infectious diseases that adversely affects the profitability of the dairy industry worldwide. Accurate diagnosis and identification of pathogens early to cull infected animals and minimize the spread of infection in herds is critical for improving treatment effects and dairy farm welfare. The major pathogens causing mastitis and pathogenesis are assessed first. The most recent and advanced strategies for detecting mastitis, including genomics and proteomics approaches, are then evaluated. Finally, the advantages and disadvantages of each technique, potential research directions, and future perspectives are reported. This review provides a theoretical basis to help veterinarians select the most sensitive, specific, and cost-effective approach for detecting bovine mastitis early.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.42-48
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• 2017

This study was conducted to compare the effect of bagging technique on the presence of pesticide residues in various parts of grape fruit (whole fruit, pulp and peel). The tested pesticides were diluted at 2,000 times and sprayed three times onto the crops at an interval of seven days and then they were collected at 0, 1, 3, 5 and 7 days after final application. Later, bagging/non-bagging samples were pre-treated with fruit, pulp and peel samples, respectively. Thiacloprid and lufenuron were not detected in any of the bagging samples. The thiacloprid residues of non-bagging samples in whole, peel and pulp samples were 0.47-1.09, 0.18-0.33 and 1.24-1.67 mg/kg, respectively. The lufenuron residues of non-bagging samples in whole fruit, peel and pulp samples were 0.16-0.62, < LOD-0.08 and 0.85-1.48 mg/kg, respectively. The biological half-lives of thiacloprid and lufenuron in whole fruit, peel and pulp of non-bagging samples were 5.7, 15.1 and 7.8 days and 4.0, 9.4 and 2.6 days, respectively. While the unbagged samples showed a sequential decrease in pesticide residues, this study concludes that bagging would be an effective method to protect the presence of thiacloprid and lufenuron residues in grape fruits.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.112-122
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• 2023

We assessed the pesticide residues in the medicinal agricultural products distributed in Korea. Pesticide residues in 72 samples were analyzed using the QuECheRS method for 339 pesticides, using GC-MS/MS and LC-MS/MS. The pesticide residues were below the maximum residues limit (MRL) in 42 samples (58.3%); however, they exceeded the MRL in 5 samples (6.9%). These included 43 types of pesticides; 20 fungicides and 23 insecticides were detected 75 times and 58 times, respectively. Tebuconazole and carbendazim were the most detected fungicides, each 11 times. The levels of acetamiprid, cadusafos, chlorpyrifos, flubendiamide, fluopyram, and triazophos exceeded the MRL in Gogi berry, Omija, and Reishi mushroom. All of them were positive list system (PLS) items that lacked pesticide residue standards. Therefore, authorities should monitor the distributed medicinal agricultural products.

• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.249-259
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• 2022

This study investigated pesticide residues in 7,069 agricultural products distributed in the city of Incheon from 2019 to 2021. Ingestion of pesticides can cause serious carcinogenic, endocrine, neurological, and reproductive problems. Pesticide residues in the samples were analyzed using various multi-residue methods (GC-MS/MS, GC-ECD/NPD, LC-MS/MS, and HPLC-UVD) on the Korean Food Code. The violation rate of the samples exceeding the maximum residue level (MRL) of pesticide residues for the years 2019, 2020, and 2021 was 1.0%, 1.4%, and 1.1%, respectively. Diazinon, flubendiamide, procymidone, fluxametamide, and fluquinconazole were the most frequently reported violative pesticide residues. Most commonly encountered agricultural products exceeding MRLs were coriander leaves, chamnamul, chwinamul, welsh onion, and crown daisy. Agricultural products and pesticides frequently exceeding MRLs should be continuously inspected for food safety. Continuous monitoring of pesticide residues in agricultural products is indispensable to improve consumer safety by preventing the distribution of agricultural products exceeding MRLs.

• Korean Journal of Environmental Agriculture
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• v.42 no.2
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• pp.139-151
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• 2023

Sulfonylurea herbicides are widely used in agriculture because they have a long residual period and high selectivity. An analytical method was developed using QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) technique for simultaneous determination of sulfonylurea herbicide residues in agricultural products by liquid chromatography tandem mass spectrometry and for establishment MRL (Maximum Residue Limit) of those herbicides in Korea. Extraction was performed using acetonitrile containing 0.1% formic acid with MgSO₄ (anhydrous magnesium sulfate) and NaCl (sodium chloride) and the extract was cleaned up using MgSO₄ and C₁₈ (octadecyl). The matrix-matched calibration curves were composed of 7 concentration levels from 0.001 to 0.25 mg/kg and their coefficients of determination (R²) exceeded 0.99. The recoveries of three spiking levels (LOQ, 10LOQ, 50LOQ, n=5) were in the range of 71.7-114.9% with relative standard deviations of less than 20.0% for all the five agriculture products. All validation values met criteria of the European Union SANTE/11312/2021 guidelines and Food and Drug Safety Evaluation guidelines. Therefore, the proposed analytical method was accurate, effective, and sensitive for sulfonylurea herbicide residues determination in agricultural commodities.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.214-223
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• 2013

BACKGROUND: This study focused on the development of an analytical method about dichlorprop (DCPP; 2-(2,4-dichlorophenoxy)propionic acid) which is a plant growth regulator, a synthetic auxin for agricultural commodities. DCPP prevents falling of fruits during their growth periods. However, the overdose of DCPP caused the unwanted maturing time and reduce the safe storage period. If we take fruits with exceeding maximum residue limits, it could be harmful. Therefore, this study presented the analytical method of DCPP in agricultural commodities for the nation-wide pesticide residues monitoring program of the Ministry of Food and Drug Safety. METHODS AND RESULTS: We adopted the analytical method for DCPP in agricultural commodities by gas chromatograph in cooperated with Electron Capture Detector(ECD). Sample extraction and purification by ion-associated partition method were applied, then quantitation was done by GC/ECD with DB-17, a moderate polarity column under the temperature-rising condition with nitrogen as a carrier gas and split-less mode. Standard calibration curve presented linearity with the correlation coefficient ($r^2$) > 0.9998, analysed from 0.1 to 2.0 mg/L concentration. Limit of quantitation in agricultural commodities represents 0.05 mg/kg, and average recoveries ranged from 78.8 to 102.2%. The repeatability of measurements expressed as coefficient of variation (CV %) was less than 9.5% in 0.05, 0.10, and 0.50 mg/kg. CONCLUSION(S): Our newly improved analytical method for DCPP residues in agricultural commodities was applicable to the nation-wide pesticide residues monitoring program with the acceptable level of sensitivity, repeatability and reproducibility.

• Korean Journal of Veterinary Service
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• v.38 no.1
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• pp.25-30
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• 2015

Bee venom has been used as to prevent and treat bovine mastitis as natural antimicrobial compounds in some dairy cattle farms in Korea. It is needed to determine the residual of bee venom in milks of dairy cattle treated with bee venom. Since bee venom is not approved as a raw material for animal drugs, the preprocessing method to detect bee venom residual in milk and the tolerance limit for its residue has not been established yet in Korea. Therefore, the purpose of this study was to develop pre-processing method not affecting major component of bee venom for detection of its residue in milks using ultra-high performance liauid chromatography (UHPLC). In addition, bee venom residue was also analyzed in milk samples of dairy cattle treated for mastitis with bee venom using UHPLC with the developed pre-processing method in this study. As a result, melittin, histamin and phospolipase A2, the major components of bee venom, were all detected by UHPLC with the pre-processing method developed in this study. The results of this study suggest that the pre-processing method developed in this study can be useful to detect bee venom residue in dairy cattle milk. We also found that no bee venom residues were detected in milk samples collected from dairy cattle treated with bee venom after 1 and 3 days, respectively.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.12a
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• pp.315-320
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• 1999