• Title/Summary/Keyword: 전처리법

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Development of a Colorimetric Rapid Detection Method for Organophosphorus and Carbamate Pesticides using Gold Nanoparticle Aggregation Principle (금 나노 입자 응집 원리를 이용한 유기인계와 카바메이트계 비색-신속 농약검출법 개발)

  • Kim, Hyo-In;Lee, Jeong-Eun;Kim, Sol-A;Moon, Hyo-Yeong;Cho, Sung-Rae;Shim, Won-Bo
    • Journal of Food Hygiene and Safety
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    • v.34 no.3
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    • pp.269-276
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    • 2019
  • A colorimetric rapid detection method based on acetylcholinesterase (AChE) was developed for the analysis of organophosphorus (OP) and carbamate (CB) pesticides. The AChE catalyzes acetylthiocholine into thiocholine having (-) and (+) charges, and the (+) charge results in gold nanoparticle (GNP) aggregation. The in-activation of AChE by OP and CB has been well known. In order to optimize the colorimetric method, optimal dilution times of commercial serum containing AChE, diameter of GNP, and concentration of acetylthiocholine were tested as a key parameter. The colorimetric detection limits of the method were 7.5 ng/mL for both dimethyl amine and carbofuran pesticides in 60% ethanol. No cross-reaction to other chemicals, such as aflatoxin B1 and ochratoxin A, which can be contaminated with pesticides in agricultural products, was observed. Recoveries from lettuce, sesame leaf, and cabbage lettuce spiked with known concentrations of dimethyl amine and carbofuran were found to be ranged from 83.85 to 133.16%. These results indicated that the colorimetric rapid method based on AChE can be a useful tool for the sensitive, specific, rapid, and accurate detection of OP and CB pesticides in fresh vegetables.

Monitoring Heavy Metals in Meat and Meat Products (식육 및 그 가공품의 중금속 모니터링)

  • Hwang, Tae-Ik;Ahn, Tae-Hyun;Kim, Eun-Jung;Lee, Jung-Ah;Kang, Myoung-Hee;Jang, Young-Mi;Kim, Mee-Hye
    • Korean Journal of Food Science and Technology
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    • v.43 no.5
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    • pp.525-531
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    • 2011
  • This study was conducted to examine the contents of lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in meat and meat products in Korea. The contents of Pb, Cd, As, and Hg in 466 samples of beef, pork, chicken, duck, ham, and sausage were measured using inductively coupled plasma mass spectrometry or a mercury analyzer. Wet ashing and microwave method were compared, and the recovery and reproducibility of the microwave method were better than those of wet ashing for meat and meat products. The recovery of the microwave method was 98.1% for Pb, 104.6% for Cd, and 103.4% for As, respectively. The best result was obtained through digestion using an acid mixture ($HNO_3$/$H_2O_2$, 6:2). Hg content was measured using a mercury analyzer. As a result, the contents of Hg and Cd in samples were lower than those of Pb and As. The average contents of Pb were 0.009 mg/kg in beef, 0.010 mg/kg in pork, 0.006 mg/kg in chicken, 0.007 mg/kg in duck, 0.005 mg/kg in ham, and 0.009 mg/kg in sausage. The average Cd contents were 0.0004 mg/kg in beef, 0.0004 mg/kg in pork, 0.0005 mg/kg in chicken, 0.0012 mg/kg in duck, 0.0015 mg/kg in ham, and 0.0019 mg/kg in sausage. The average As contents were 0.016 mg/kg in beef, 0.004 mg/kg in pork, 0.021 mg/kg in chicken, 0.010 mg/kg in duck, 0.014 mg/kg in ham, and 0.018 mg/kg in sausage. The average Hg contents were 0.713 ${\mu}g/kg$ in beef, 0.902 ${\mu}g/kg$ in pork, 0.710 ${\mu}g/kg$ in chicken, 0.796 ${\mu}g/kg$ in duck, 1.141 ${\mu}g/kg$ in ham, and 1.052 ${\mu}g/kg$ in sausage. Based on the results of the National Health and Nutrition Survey 2005, the levels of dietary exposure to heavy metal contaminants in meat and meat products were compared with the provisional tolerable weekly intake(PTWI) established by the Joint FAO/WHO Expert Committee on Food Additives. The average dietary exposure of the general population from meat and meat products was 0.03-0.2% of PTWI for Pb, Cd, As, and Hg, which indicates a safe level for public health at present.

The analysis of pesticide residue in leafy vegetables using the modified QuEChERS pre-treatment methods (QuEChERS 시료 처리법을 활용한 엽채류 중 잔류농약분석)

  • Kim, Yang-Hyeon;Hong, Su-Myeong;Son, Kyung-Ae;Lee, Ju-Young;Min, Zaw Win;Kwon, Hye-Young;Kim, Taek-Kyum;Kyung, Kee-Sung
    • The Korean Journal of Pesticide Science
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    • v.16 no.2
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    • pp.121-130
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    • 2012
  • In analyzing pesticide residue, LLE (liquid liquid extraction) is generally applied as one of the existing methods, but needed quite a lot of organic solvents and analytical apparatuses for the sample pre-treatment. In addition to its long analysis time and complex analytical processes, it is required to develop a more rapid and efficient method at present. In order to establish an economic and simple pesticide residue analytical method, this study carried out a comparative experiment on the existing analytical method with a new sample pre-treatment method named QuEChERS (quick, easy, cheap, effective, rugged and safe), which extracts and refines pesticide components by directly adding solid powder into the sample. Both the two analytical methods showed favorable values of correlation coefficient ($R^2$ > 0.99) of calibration curves. In terms of the detection limit (identification limit), imidacloprid showed 0.02 mg/kg, while the rest of pesticides showed a level around 0.05 mg/kg. The results of this experiment revealed that the recovery of LLE was 92.8-100.9% and the RSD was below 2.5%. On the other hand, the recovery of QuEChERS was 92.2-101.6% and RSD was below 1.9%. As a result of comparing the amount of pesticide residue by the time between the two analytical methods by using Paired t-Test, there was no significant difference between the two analytical methods as the p-value ranged from 0.3148-0.9890. Considering the results of the two methods, the QuEChERS method had similar recovery, compared to the analytical method using the existing LLE, and the analytical time was shortened by about one fourth of that of the existing method. Moreover, since it excludes the use of harmful organic solvents like dichloromethane during the process of extraction, thus leading to protecting experimenters health and remarkably reducing the amount of disused solvents, it is judged as an echo-friendly and economic analytical method.

Analysis of PAHs (polycyclic aromatic hydrocarbons) in Ground Coffee Using GC-tandem Mass Spectrometry and Estimation of Daily Dose (GC-tandem mass spectrometry를 이용한 분쇄원두커피 중 PAHs(polycyclic aromatic hydrocarbons) 분석법 연구 및 인체노출량 평가)

  • Jung, So-Young;Park, Ju-Sung;Son, Yeo-Joon;Choi, Su-Jeong;Lee, Yun-Jeong;Kim, Mi-Sun;Park, So-Hyun;Lee, Sang-Me;Chae, Young-Zoo
    • Korean Journal of Food Science and Technology
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    • v.43 no.5
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    • pp.544-552
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    • 2011
  • The purpose of this study was to develop an analytical method for determining 15 polycyclic aromatic hydrocarbons (PAHs) of EU priority using gas chromatography (GC)-tandem mass spectrometry (MS). The PAHs in ground coffee were analyzed after being extracted using methods such as saponification-liquid-liquid extraction, Soxhlet extraction, and solid-liquid extraction. The solid-liquid extraction method showed the greatest repeatability and most efficient reduction of the matrix effect. GC-tandem MS for the quantification of the 15 PAHs showed better resolution and lower limit of detections (LODs) than GC-MS-selected ion monitoring (SIM) and high performance liquid chromatography with fluorescence detector. LODs of this method for the ground coffee types were 0.002-0.1 ${\mu}g/kg$ and limit of quantifications (LOQs) were 0.006-0.2 ${\mu}g/kg$ The recoveries ranged from 52.6 to 93.3%. Forty-six commercial types of ground coffee were analyzed to determine their PAHs contamination levels. PAHs concentration ranged from ND to 5.988 ${\mu}g/kg$. This study was conducted with toxicity equivalence factors, the U.S. EPA recommendation to identify dietary risks for PAHs in different types of coffee. The estimated average daily dose of PAHs was $5.24{\times}10^{-8}$ mg/kg body weight/day.

Trends in Rapid Detection Methods for Marine Organism-derived Toxins (해양 생물 유래 독소의 나노 기술 기반 신속 진단법 개발 동향)

  • Park, Chan Yeong;Kweon, So Yeon;Moon, Sunhee;Kim, Min Woo;Ha, Sang-Do;Park, Jong Pil;Park, Tae Jung
    • Journal of Food Hygiene and Safety
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    • v.35 no.4
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    • pp.291-303
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    • 2020
  • Marine organism-derived toxins have negative effects not only on human health but also in aquaculture, fisheries, and marine ecosystems. However, traditional analytical methods are insufficient in preventing this threat. In this paper, we reviewed new rapid methods of toxin detection, which have been improved by adopting diverse types of nanomaterials and technologies. Moreover, we herein describe the main strategies for toxin detection and their related sensing performance. Notably, to popularize and commercialize these newly developed technologies, simplifying the process of pre-treating real samples real samples is very important. As part of these efforts, numerous studies have reported pretreatment methods based on the antibody-immobilized magnetic nanoparticles, and some cases have applied nanoparticles to enhance the sensing performance by utilizing the intrinsic catalytic activity. Furthermore, some reports have introduced fluorescent nanoparticles, such as quantum dots, to represent the lower detection limits of conventional enzyme-based colorimetric methods and lateral flow assays. Some studies using electrochemical measurements based on aptamer-nanoparticle complexes have also been announced. In addition, as the response to new toxins generated by changes in the marine environment is still lacking, further research on diagnostic and detection is also greatly needed for these kinds of marine toxins and their derivatives.

Monitoring and Risk Assessment of Pesticide Residues in Herbal Medicines in Incheon (인천광역시 유통 한약재의 잔류농약 실태 조사 및 위해평가)

  • Min-jeong Kang;Sung-Hee Kwon;Sun-Hoi Kim;Mi-Sook Yeom;Byung-Kyu Park;Hee-jeong Lee;Ji-Hyeung Kim;Kwang-sig Joo;Myung-je Heo;Mun-ju Kwon
    • Journal of Food Hygiene and Safety
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    • v.39 no.2
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    • pp.118-127
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    • 2024
  • This study investigated the levels of 345 pesticide residues in 50 herbal medicines sold in Incheon metropolitan city to determine their safety. Pesticide residues are harmful substances that can cause serious health problems owing to their toxicity and carcinogenicity. The analysis of pesticide residues in the samples was conducted using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method, known for its high analysis efficiency, to analyze a wide range of pesticides for which no standards have been set. The analysis was cross-validated with the pretreatment method outlined in the Korea Pharmacopoeia. Among the 50 samples encompassing 24 different herbs, 22 pesticide residues were detected in 24 samples, covering 7 distinct herbs, resulting in a detection rate of 48%. It is noteworthy that, except for two cases, all detected pesticides were those for which no standards were set. However, after conducting a risk evaluation considering the daily dosage of herb, it was determined that the levels of pesticide residues were within safe limits. Pesticides with high frequency within the same category of herbs were detected, indicating the necessity for continuous monitoring and regulation. In addition, comparative analysis using the pretreatment method outlined in the Korean Pharmacopoeia, yielded similar results, suggesting the possibility of analyzing pesticide residues in herbs using the QuEChERS method. The study emphasizes the importance of continuous monitoring of pesticide residues in herbs and the development of high-efficiency reliability analysis methods should continue to ensure consumer safety.

A study on oil-contaminated fingerprints developing (유지문 현출법에 관한 연구)

  • Choi, Mi-Jung;Park, Won-Seok;Kim, Man-Ki;Jeon, Chung-Hyun;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.23 no.1
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    • pp.89-96
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    • 2010
  • In general, three types of fingerprints could be found at the crime scene: visible, plastic, and latent fingerprints. Examples of visible fingerprint include those made by blood, paint or ink. Plastic fingerprint are made from an impression of the finger on soft material as soap, wax, etc. Latent fingerprint are those of the invisible one to the human eye. Oil-contaminated fingerprints remained in the evidence, that are contaminated with the soybean oil, engine oil, lubricating oil or grease. Oil-contaminated fingerprints are special types of fingerprint evidence but the research for developing method regarding oil-contaminated fingerprints is a few. In this study, ultraviolet light source was employed for untreated oil-contaminated prints and the freeze-dry method with liquid nitrogen for freeze oil residue on the surfaces with sequence of developing oil-contaminated fingerprints with black and magnetic powders, cyanoacrylate (CA) fuming, Basic Yellow 40. The types of oil chosen for the experiment were soybean oil, LSA oil, engine oil and material surfaces selected for the experiment were glass, plastic aluminum plates. The aims of this study were to determine the appropriate developing methods for oil-contaminated fingerprints.

Monitoring Ochratoxin A in Coffee and Fruit Products in Korea (커피 및 과실류 가공품의 오크라톡신 A 모니터링)

  • Park, Ji-Eun;Heo, Seok;Lee, Mi-Seon;Kim, Eun-Jung;Park, Jong-Seok;Oh, Jae-Ho;Jang, Young-Mi;Kim, Mee-Hye
    • Korean Journal of Food Science and Technology
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    • v.42 no.3
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    • pp.263-268
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    • 2010
  • This research was conducted to evaluate the occurrence of ochratoxin A (OTA) in coffee and fruit products in Korea. A total of 388 coffee and fruit product samples were collected from retail or outlet markets; 177 samples were coffee and 211 were fruits or their products. Analytical methods including AOAC and Comit$\acute{e}$ Europ$\acute{e}$en de Normalisation (CEN) were selected and modified by method validation to detect and quantify the OTA in samples. All samples were analyzed by liquid chromatography with fluorescence detection. OTA was detected in 3.9% of 177 kinds of coffee and 0% of 211 kinds of fruit products. The levels of OTA were $0.7-4.6\;{\mu}g/kg$ in green coffee, $0.3-4.8\;{\mu}g/kg$ in roasted coffee, $1.4\;{\mu}g/kg$ in mixed coffee, and $0.4-0.6\;{\mu}g/kg$ in instant coffee. However, OTA was not detected in liquid coffee, dried fruits, or grape juice. OTA levels of all samples detected were less than the European Union legislation of $5.0\;{\mu}g/kg$ in coffee, $10.0\;{\mu}g/kg$ in raisins and $2.0\;{\mu}g/kg$ in grape juice. Therefore, the risk of OTA in coffee and fruit products in Korea is relatively low at safe levels.

Identification of Faulty Red Pepper Powder Containing Seasoned Red-pepper Sauce (고추다대기 혼입 불량고춧가루 판별법 개발)

  • Park, Yong-Chjun;Lim, Ji-Young;Kim, Mi-Ra;Park, Young-Eun;Lim, Jan-Di;Hwang, Cho-Rong;Kim, Kyu-Heon;Lee, Jae-Hwang;Cho, Tae-Yong;Lee, Hwa-Jung;Lee, Sang-Jae;Han, Sang-Bae
    • Journal of Food Hygiene and Safety
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    • v.27 no.2
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    • pp.182-187
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    • 2012
  • In this study, the experimental method has been investigated using molecular biological way to identify raw materials from seasoned red-pepper sauce which is one of the most popular spices in Korea. 6 kinds of seasoned red-pepper sauces were chosen as a sample containing chilli pepper, garlic, onion as a major ingredient and species specific primers were used for the identification of the raw material of processed food. Selected samples were pre-treated to remove salt (samples were washed with distilled water 3~4 times for desalting), after that, to amplify the extracted genes, whole genome amplification (WGA) kit was performed. Afterwards, PCR products were confirmed through the electrophoresis. As a result, 102, 180, 280 bp of specific PCR products were confirmed for each major ingredients such as chilli pepper, garlic, onion. From this study, the gene extraction method was validated for the identification of ingredients from the spices and it would be applied to distinction of low quality chilli pepper powder including seasoned red-pepper sauce illegally.

Enzymatic Hydrolysis of Yellowfin Sole Skin Gelatin in a Continuous Hollow Fiber Membrane Reactor (연속식 중공사막 반응기를 이용한 각시가자미피 젤라틴의 가수분해)

  • KIM Se-Kwon;BYUN Hee-Guk;KANG Tae-Jung;SONG Dae-Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.2
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    • pp.120-132
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    • 1993
  • A continuous hollow fiber membrane reactor(CHFMR) was developed and optimized for the production of yellowfin sole(Limanda aspera) skin gelatin hydrolysates using trypsin. The results were summerized as follows: The $K_m$ value of the CHFMR was 2.4 times higher than that of the batch reactor, indicating reduced enzyme affinity for the substrate. The $K_2$ value of the CHFMR was 8.5 times lower than that of the batch process, showing a significant reduction in trypsin activity in the CHFMR. The optimum operating conditions for the CHFMR process were $55^{\circ}C$, pH 9.0, flux 7.79 ml/min, residence time 77min, and trypsin to substrate ratio, 0.01(w/w) After operating for 60min under the above conditions, $79\%$ of the total amount of initial gelatin was hydrolysed. Enzyme leakage was observed through the 10,000 MWCO membrane after the 20min of reactor operation, while none occurred after 5hr. Total enzyme leakage was about $12.95\%$ at $55^{\circ}C$ for 5hrs. However, there was no apparent correlation between enzyme leakage and substrate hydrolysis. The membrane has a significant effect on trypsin activity loss for 60min of the CHFMR operation. The CHFMR operating with the membrane lost $34\%$ of the initial activity versus a $23\%$ loss of activity after 3hr in the continuous reactor lacking the hollow fiber membrane. The measurement of fouling property showed that relative flux reduction was $91\%$ and flux recover rate was $92\%$ at $10\%$ substrate solution. The productivity(378.85mg product/mg enzyme) of the CHFMR was more than 4 times higher than that of the batch reactor at $55^{\circ}C$.

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