• Journal of Food Hygiene and Safety
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• v.30 no.3
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• pp.272-280
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• 2015

A simultaneous official method was developed for the determination of phorate and its metabolites (phorate sulfoxide, phorate sulfone, phorate oxon, phorate oxon sulfoxide, phorate oxon sulfone) in livestock samples. The analytes were quantified and confirmed via liquid chromatograph-tandem mass spectrometer (LC-MS/MS) in positive ion mode using multiple reaction monitoring (MRM). Phorate and its metabolites were extracted from beef and milk samples with acidified acetonitrile (containing 1% acetic acid) and partitioned with anhydrous magnesium sulfate. Then, the extract was purified through primary secondary amine (PSA) and C18 dispersive sorbent. Matrix matched calibration curves were linear over the calibration ranges (0.005-0.5 mg/L) for all the analytes into blank extract with $r^2$ > 0.996. For validation purposes, recovery studies were carried out at three different concentration levels (beef 0.004, 0.04 and 0.2 mg/kg; milk 0.008, 0.04 and 0.2 mg/kg, n = 5). The recoveries were within 79.2-113.9% with relative standard deviations (RSDs) less than 19.2% for all analytes. All values were consistent with the criteria ranges requested in the Codex guidelines. The limit of quantification was quite lower than the maximum residue limit (MRL) set by the Ministry of Food and Drug Safety (0.05 mg/kg). The proposed analytical method was accurate, effective and sensitive for phorate and its metabolites determination and it will be used to as an official analytical method in Korea.

• The Korean Journal of Food And Nutrition
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• v.16 no.1
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• pp.22-28
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• 2003

Kimchi made with the addition of 2 percent of boiled young antler, raw young antler, young antler treated with lactic acid(acid treated young antler) has been fermented for 15 days at 11$^{\circ}C$. After 15 days of fermentation, the results show that pH of boiled young antler Kimchi was 3.87, that of raw young antler Kimchi was 4.04, acid treated young antler Kimchi was 3.97, control Kimchi was 3.86, and acidity of boiled young antler Kimchi was 7.4, that of raw young antler Kimchi was 10.5, that of acid treated young antler Kimchi was 10.7, control Kimchi was 6.9, respectively. After 15 days, total sugar content was 1.46% in boiled young antler Kimchi, 0.53% in raw young antler Kimchi, 0.92% in acid treated young antler Kimchi, 1.46% in control Kimchi, and reducing sugar was 0.50% in boiled young antler Kimchi, 0.14% in raw young antler Kimchi, 0.39% in acid treated young antler Kimchi and control Kimchi, respectively. Amino acid content was 13.42${\mu}$㏖/$m\ell$ in boiled young antler Kimchi, 17.83${\mu}$㏖/$m\ell$ in raw young antler Kimchi, 14.48${\mu}$㏖/$m\ell$ in acid treated young antler Kimchi, 17.60${\mu}$㏖/$m\ell$ in control Kimchi, and protein was 2.101% in boiled young antler Kimchi, 1.945% in raw young antler Kimchi, 1.722% in acid treated young antler Kimchi and 2.011% in control Kimchi, respectively. Lactic acid content was 2.021% in raw young antler Kimchi, 2.004% in acid treated young antler Kimchi, 1.950% in boiled young antler Kimchi, 1.200% in control Kimchi, and succinic acid was 0.081% in boiled young antler Kimchi, 0.086% in raw young antler Kimchi, 0.078% in acid treated young antler Kimchi and 0.111% in control Kimchi, respectively. Acetic acid was 0.080% in boiled young antler Kimchi, 0.092% in raw young antler Kimchi, 0.114% in acid treated young antler Kimchi, 0.086% in control Kimchi, respectively. The number of microorganism was 1.09${\times}$ 10$\^$8//g in boiled young antler Kimchi, 1.08${\times}$10$\^$8//g in control Kimchi, 9.88${\times}$10$\^$8//g in acid treated young antler Kimchi and 6.6${\times}$ 10$\^$8//g in raw young antler Kimchi. The number of microorganism was highest in acid treated young antler Kimchi, and followed by raw young antler Kimchi, and boiled young antler Kimchi, control Kimchi, respectively. The results of test of the saltness, sour, aroma, color, texture through sensory evaluation reveal that boiled young antler Kimchi has the excellent taste, and followed by raw young antler Kimchi and control Kimchi, acid treated young antler Kimchi, respectively.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.507-513
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• 2001

An effective extraction methods of a garlic were investigated in order to improve the functional properties of the extracts. The solid yield, electron donating ability (EDA), nitrite-scavenging effects (NSE), peroxide value (POV) and total thiosulfinates contents of garlic extracts were determined. In order to improve the functional properties of extracts prepared with several organic solvents and acids, concentration and pH adjustment of the selected solvent and addition of acids and salts to solvents were also examined. Among the solvents tested, the methanol and ethanol extracts were found to be the most effective on the base of functionality and solid yields. The highest EDA, NSE and thiosulfinate value were obtained with 50% ethanol. The pH control of solvent and addition of citric acid, NaCl and phosphates to 50% ethanol did not affect on the functionality of the extracts. Therefore the optimal solvent for the best functional properties of garlic extract was 50% ethanol.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4940-4950
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• 2011

cis-(3R,5R)-Atorvastatin Ca (1) used for hyperlipidemia have four stereomers. However, It is very difficult to prepare stereoselective stereomers. In this paper, the reduction of 3,5-diketo atorvastatin ester (3) was performed using $Me_4NHB(OAc)_3$ in acetic acid as a reductant and showed excellent stereoselectivity in the double reduction of 3,5-diketo atorvastatin ester (3). As a result, reduction of compound 3 by $Me_4NHB(OAc)_3$ was purely obtained with cis-(3R,5R)-atorvastatin ester (4) of 1.5% and trans-(3R,5S)-atorvastatin ester (5) of 98.5%. Also, cis-(3R,5R)-atorvastatin Ca (1) and trans-(3R,5S)-atorvastatin Ca (7) were used to determine efficacy in the treatment of liver damage and hyperlipidemia induced by a high-fat diet in rats and to study the performance of the January 2010 experient was conducted. As a result, total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-c), low-density lipoprotein-cholesterol (LDL-c), and triglyceride (TG) levels of compound 1 and 7 groups were $93.0{\pm}0.5$, $43.5{\pm}0.8$, $40.4{\pm}1.4$, $45.6{\pm}0.9\;mg/d{\ell}$ and $110.0{\pm}0.7$, $33.3{\pm}0.6$, $65.8{\pm}1.9$, $54.8{\pm}1.2\;mg/d{\ell}$, respectively. Atherogenic index (AI) and cardiac risk factor (CRF) in compound 1 and 7 were $1.14{\pm}0.05$, $2.14{\pm}0.05$ and $2.31{\pm}0.06$, $3.31{\pm}0.06$, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were $51.9{\pm}4.6$, $16.0{\pm}2.1\;IU/{\ell}$ and $75.8{\pm}4.4$, $35.1{\pm}9.7\;IU/{\ell}$. Taken together, while compound 1 treat against high-fat diet-induced hyperlipidemia by attenuating hepatic lipid depots and reducing oxidative stress, compound 7 group had a low curative effect on hyperlipidemia induced by a high-fat diet in rats. These findings suggest that new method about synthesis of stereoselective stereomers and indicate that it may consider using in a clinical trial.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.366-371
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• 2006

This study was done to assess the physical and chemical properties after anaerobic fermentation treatment which use rice bran or wheat bran in plastic film house soil. The results which investigates the change of soil physical property after treatment 150 days showed a dramatic difference. The physical properties of control soil were the bulk density $1.46Mg\;m^{-3}$, hardness $2.30Kg\;cm^{-3}$, hydraulic conductivity $4.8cm\;hr^{-1}$, water stable aggregate(>0.5mm) 6.7%. Of the soil which treatment the rice bran in comparison to control soil, bulk density and hardness was diminished 12% and 58%, respectively. hydraulic conductivity and water stable aggregate(>0.5mm) were increased 4.5 and 5.2 fold, respectively. And, in the soil which treatment the wheat bran, bulk density and hardness was diminished 14% and 67%, respectively. Hydraulic conductivity and water stable aggregate(>0.5mm) were increased 6.3 and 6.5 fold, respectively. $NO_3-N$ contents of the soil which treated the rice bran or wheat bran after treatment 20 days were diminished 98% in comparison to control soil. The decrease of $NO_3-N$ contents in the soil was investigated with the fact that it is caused by with increase of the soil-microbial biomass. EC of the soil which treated the rice bran were $1.48dS\;m^{-1}$ which was diminished 58% in comparison to control soil. That of soil which treated the wheat bran was increased $3.65dS\;m^{-1}$ in the early stage because of acetic and butyric acid. But it was reduced as under $2.0dS\;m^{-1}$ after treatment 30 days. As the conclusion the anaerobic fermentation treatment with rice or wheat bran was effective to the improvement of soil physical and salt accumulation of the plastic film house soil.

• Journal of Life Science
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• v.29 no.6
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• pp.688-696
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• 2019

This study investigated changes in triglyceride and cholesterol synthesis and tyrosinase activity induced by ice plant (Mesembryanthemum crystallinum L.) extract, which cannot be stored for long periods of time due to its high moisture content when it was fermented to improve its storage stability. The accumulation of triglyceride and cholesterol in HepG2 cells inhibited the accumulation with a relatively large magnitude in n-butanol and aqueous fractions that generally have high polarity, however, changes in inhibition potency due to the fermentation were not significant. As for the effect to inhibit tyrosinase activity, when L-tyrosine was used as a substrate, the inhibitory activity was the highest for the aqueous fraction at $60.58{\pm}4.03%$ and $63.35{\pm}4.35%$, before and after fermentation, respectively, which amounted to 72% of that of the positive control group (arbutin, $100{\mu}g/ml$). In addition, when L-3,4-dihydroxyphenylalanine (L-DOPA) was used as a substrate, the inhibitory activity was also found the highest for the aqueous fraction at $56.85{\pm}1.57%$ and $59.38{\pm}1.74%$, before and after fermentation, respectively, which amounted to at least 88% of that in the positive control (kojic acid, $100{\mu}g/ml$). Overall, the activity of the fermented ice plant extract was similar or a little higher compared to that of the one without fermentation, indicating that fermentation can be a good approach to improve the storage stability of the ice plant.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.1
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• pp.64-68
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• 2019

Purpose In the preparation process for N-13 Ammonia injections, there were radioactive medicines adsorbed on filters remarkably. Hereby, we have compared the adsorption rate and quality test on Millex GS filter and Satorious Minisart filter, both representatively hydrophilic sterilizing filters, also evaluated which filter is more accommodative for N-13 Ammonia injection. Materials and Methods The filters used for sterilization of N-13 Ammonia injections were Millex GS filter($0.22{\mu}m$) mand Satorious Minisart filter ($0.2{\mu}m$), which are generally used to strain aqueous solutions. After the N-13 Ammonia passes through each sterilization filter, the adsorption rate of the filter (n=10) is determined by measuring not only the radioactivity through the filter also the amount of radioactivity remaining in it using a Dose Calibrator. The N-13 Ammonia injections after each filter is tested by the quality control test to conform to the Samsung Medical Center standard. Results The ratio of radioactivity passed through Millex GS indicated $29.0{\pm}17.6%$. Satorious Minisart filters output was $80.9{\pm}3.2%$, respectively. Each ratio of radioactivity adsorbed on the sterile filter was $71.0{\pm}17.6%$ for Millex GS and $19.1{\pm}3.2%$ for the Satorious Minisart filters, respectively. Furthermore, on the ratio of filtered radioactivity, Using Satorious Minisart filter showed about 2.8 times higher than using Millex GS filter. The quality testing of N-13 Ammonia injections through each filter met the Samsung Medical Center standard. Conclusion The Millex GS filter is composed of cellulose acetate and cellulose nitrate, whereas the Satorious Minisart filter if composed only of cellulose acetate. Therefore, the presence of cellulose nitrate in the membrane seems to have made differences. Therefore, the use of Satorious Minisart filter in the preparation of N-13 Ammonia injection solution minimized the loss of radioactive medicines due to filter adsorption, thereby improving the synthesis yield.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.2
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• pp.74-78
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• 2018

Purpose $[^{11}C]$acetate has been proved useful in detecting the myocardial oxygen metabolism and various malignancies including prostate cancer, hepatocellular carcinoma, renal cell carcinoma and brain tumors. The purpose of study was to improve the radiosynthesis yield of $[^{11}C]$acetate on a automated radiosynthesis module. Materials and Methods $[^{11}C]$acetate was prepared by carboxylation of grignard reagent, methylmagnesium chloride, with $[^{11}C]$$CO_2$ gas, followed by hydrolysis with 1 mM acetic acid and purification using solid phase extraction cartridges. The effect of the reaction temperature ($0^{\circ}C$, $10^{\circ}C$, $-55^{\circ}C$) and cyclotron beam time (10 min, 15 min, 20 min, 25 min) on the radiosynthesis yield were investigated in the $[^{11}C]$acetate labeling reaction. Results The maximum radiosynthesis yield was obtained at $-10^{\circ}C$ of reaction temperature. The radioactivities of $[^{11}C]$acetate acquired at $-10^{\circ}C$ reaction temperature was 2.4 times higher than those of $[^{11}C]$acetate acquired at $-55^{\circ}C$. Radiosynthesis yield of $[^{11}C]$acetate increased with increasing cyclotron beam time. Conclusion This study shows that radiosynthesis yield of $[^{11}C]$acetate highly dependent on reaction temperature. The best radiosynthesis yield was obtained in reaction of grignard reagent with $[^{11}C]$$CO_2$ at $-10^{\circ}C$. This radiolabeling conditions will be ideal for routine clinical application.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.140-147
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• 2019

An analytical method was developed for the determination of quinoxyfen in agricultural products using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted with 1% acetic acid in acetonitrile and water was removed by liquid-liquid partitioning with $MgSO_4$ (anhydrous magnesium sulfate) and sodium acetate. Dispersive solid-phase extraction (d-SPE) cleanup was carried out using $MgSO_4$, PSA (primary secondary amine), $C_{18}$ (octadecyl) and GCB (graphitized carbon black). The analytes were quantified and confirmed by using LC-MS/MS in positive mode with MRM (multiple reaction monitoring). The matrix-matched calibration curves were constructed using six levels ($0.001-0.25{\mu}g/mL$) and the coefficient of determination ($R^2$) was above 0.99. Recovery results at three concentrations (LOQ, 10 LOQ, and 50 LOQ, n=5) were in the range of 73.5-86.7% with RSDs (relative standard deviations) of less than 8.9%. For inter-laboratory validation, the average recovery was 77.2-95.4% and the CV (coefficient of variation) was below 14.5%. All results were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL 40-1993, 2003) and Food Safety Evaluation Department guidelines (2016). The proposed analytical method was accurate, effective and sensitive for quinoxyfen determination in agricultural commodities. This study could be useful for the safe management of quinoxyfen residues in agricultural products.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.228-238
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• 2021

The aim of this research was to develop a rapid and easy multi-residue method for determining dimethipin, omethoate, dimethipin, chlorfenvinphos and azinphos-methyl in agricultural products (hulled rice, potato, soybean, mandarin and green pepper). Samples were prepared using QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) and analyzed using gas chromatography-tandem mass spectrometry (GC-MS/MS). Residual pesticides were extracted with 1% acetic acid in acetonitrile followed by addition of anhydrous magnesium sulfate (MgSO₄) and anhydrous sodium acetate. The extracts were cleaned up using MgSO₄, primary secondary amine (PSA) and octadecyl (C₁₈). The linearity of the calibration curves, which waas excellent by matrix-matched standards, ranged from 0.005 mg/kg to 0.3 mg/kg and yielded the coefficients of determination (R²) ≥ 0.9934 for all analytes. Average recoveries spiked at three levels (0.01, 0.1, 0.5 mg/kg) and were in the range of 74.2-119.3%, while standard deviation values were less than 14.6%, which is below the Codex guideline (CODEX CAC/GL 40).