• Title/Summary/Keyword: analysis by HPLC

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Establishment of Pre-Harvest Residue Limit (PHRL) of Fungicides Azoxystrobin and Difenoconazole on Prunus mume fruits (매실 중 살균제 azoxystrobin과 difenoconazole의 생산단계 잔류허용기준 설정)

  • Lee, Dong Yeol;Kim, Yeong Jin;Park, Min Ho;Lee, Seung Hwa;Kim, Sang Gon;Kang, Nam Jun;Kang, Kyu Young
    • The Korean Journal of Pesticide Science
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    • v.17 no.4
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    • pp.307-313
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    • 2013
  • This study was carried out to investigate the residual characteristics of fungicide azoxystrobin and difenoconazole in Prunus mume fruits, and establish pre-harvest residue limits (PHRL) based on dissipation and biological half-lives of fungicide residues. The fungicides were sprayed onto the crop at recommended dosage once and 3 times in 7 days interval, respectively. The samples were harvested at 0, 1, 2, 4, 6, 8, 10, 12 and 14 days after treatment. These residual pesticides were extracted with QuEChERS method, clean-up with $NH_2$ SPE cartridge, and residues were analyzed by HPLC/DAD and GLC/ECD, respectively. Method quantitative limits (MQL) of azoxystrobin were 0.03 mg $kg^{-1}$ and of difenoconazole were 0.006 mg $kg^{-1}$. Average recovery were $93.2{\pm}2.49%$, $85.5{\pm}1.97%$ for azoxystrobin at fortification levels at 0.3 and 1.5 mg $kg^{-1}$, and $100.8{\pm}6.74%$, $87.6{\pm}9.92%$ for difenoconazole at fortification levels at 0.06 and 0.3 mg $kg^{-1}$, respectively. The biological half-lives of azoxystrobin were 5.9 and 5.2 days at recommended dosage once and 3 times in 7 days interval, respectively. The biological half-lives of difenoconazole were 9.3 and 8.0 days at recommended dosage once and 3 times in 7 days interval, respectively. The PHRL of azoxystrobin and difenoconazole were recommended as 5.32 and 1.64 mg $kg^{-1}$ for 10 days before harvest, respectively.

Biodistribution and Hepatic Metabolism of Galactosylated $^{111}In-Antibody-Chelator$ Conjugates: Comparison with $^{111}In-Antibody-Chelator$ Conjugates ($^{111}In$-표지 갈락토즈 접합 항체의 체내분포 및 간에서의 대사 : $^{111}In$-표지 항체와의 비교연구)

  • Kwak, Dong-Suk;Jeong, Kyu-Sik;Ha, Jeoung-Hee;Ahn, Byeong-Cheol;Lee, Kyu-Bo;Paik, Chang-H.;Lee, Jae-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.37 no.6
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    • pp.402-417
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    • 2003
  • Purpose: To evaluate the use of monoclonal antibody (MoAb) as a carrier of the receptor-binding ligand the receptor mediated uptake into liver and subsequent metabolism of $^{111}In-labeled$ galactosylated MoAb-chelator conjugates were investigated and compared with those of $^{111}In$ labeled MoAb. Materials and Methods : T101 MoAb, $IgG_2$ against human lymphocytic leukemic cell, conjugated with cyclic DTPA dianhydride (DTPA) or 2-p-isothiocyanatobenzyl-6-methyl-DTPA (1B4M) was galactosylated with 2-imino-2-methoxyethyl-1-thio-${\beta}$-D-galactose and then radiolabeled with $^{111}In$. Biodistribution and metabolism study was peformed with two $^{111}In-conjugates$ in mice and rats. Results: $^{111}In-labeled$ T101 and its galactosylated conjugates were taken to the liver by the time, mostly within 10 min. However DTPA conjugate was retained longer in the liver than the 1B4M conjugate (55% vs 20% of injected dose at 44 hr). During this time, the radiornetabolite of DTPA conjugate was excreted similarly into urine (24%) and feces (17%). The radiometabolite of 1B4M was excreted primarily into feces (68%) rather than urine (8%). Size exclusion HPLC analysis of the bile and supernatant of liver homogenate showed two peaks the first (35%) with the retention time (Rt) identical to IgG and the second (65%) with Rt similar to free $^{111}In$ at 3 hr post-injection for the 1B4M conjugate, indicating that the metabolite is rapidly excreted through the biliary system. in contrast to DTPA conjugate, the small $^{111}In-DTPA-like$ metabolite was the major radioindium component (90%) in the liver homogenate as early as 3 hour post-injection, but the cumulative radioindium activity in feces was only 17% at 44 hour, indicating that the metabolite from DTPA conjugate does not clear readily through the biliary tract. Conclusion: The galactosylation of the MoAb conjugates resulted in higher hepatocyte uptake and enhanced metabolism, compared to those without galactosylation. Metabolism of the MoAb-conjugates is different between compounds radiolabled with different chelators due to different characteristics of radiometabolites generated in the liver.

Monitoring of Pesticide Residues in Leafy Vegetables Collected from Wholesale and Traditional Markets in Cheongju (청주지역 도매 및 재래시장 유통 엽채류 중 잔류농약 모니터링)

  • Noh, Hyun-Ho;Park, Young-Soon;Kang, Kyung-Won;Paik, Hyo-Kyung;Lee, Kwang-Hun;Lee, Jae-Yun;Yeop, Kyung-Won;Choi, Song-Rim;Kyung, Kee-Sung
    • The Korean Journal of Pesticide Science
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    • v.14 no.4
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    • pp.381-393
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    • 2010
  • In order to monitor the residual characteristics of the pesticides in leafy vegetables selling at wholesale markets and traditional markets in Cheongju, a total of 180 samples of 15 leafy vegetables, such as broccoli, celery, chard, chicory, Chinese vegetable, Chwinamul, crown daisy, Korean cabbage, leek, lettuce, perilla leaves, Shinsuncho, spinach, welsh onion and young radish, were purchased from the wholesale markets and traditional markets in June and August in 2010 and the pesticide residues in them were analyzed by multiresidue analysis method using GLC, HPLC and GC-MSD. Seven pesticides were detected from 12 samples out of total 180 samples collected, representing detection rate was 6.7%. In case of the samples collected from markets in June, four pesticides including tefluthrin were detected from six samples and in case of the samples collected from markets in August, three pesticides including pendimethalin were detected from three samples. The MRL-exceeding rate of pesticides detected from leafy vegetables was 0.6%. The pesticide exceeded its MRL was azoxystrobin detected from crown daisy and many pesticides were not registered to the crops, excepting that azoxystrobin detected from Chwinamul and tefluthrin from leek. Estimated daily intakes (EDIs) of the pesticides detected from leafy vegetables were less than 7% of their acceptable daily intakes (ADIs), representing that residue levels of the pesticides detected were evaluated as safe.

Bioequivalence of Burophil Capsule to Surfolase Capsule (Acebrophylline 100 mg) (설포라제 캡슐(아세브로필린 100 mg)에 대한 부로필 캡슐의 생물학적 동등성)

  • Cho, Hea-Young;Park, Eun-Ja;Kang, Hyun-Ah;Kim, Se-Mi;Park, Chan-Ho;Oh, In-Joon;Lim, Dong-Koo;Lee, Myung-Hee;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.35 no.3
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    • pp.179-185
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    • 2005
  • Acebrophylline is a compound produced by salifying ambroxol with theophylline-7 -acetic acid. After acebrophylline administration, the salt splits into these two components which feature a peculiar pharmacokinetic behavior, an adequate ambroxol and a low theophylline-7-acetic acid serum levels. The purpose of the present study was to evaluate the bioequivalence of two acebrophylline capsules, Surfolase (Hyundai Pharm. lnd. Co., Ltd.) and Burophil (Kuhnil Pharm. Co., Ltd.), according to the guidelines of the Korea Food and Drug Administration (KFDA). The release of ambroxol from the two acebrophylline formulations in vitro was tested using KP VIII Apparatus II method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty eight healthy male subjects, $23.25{\pm}1.43$ years in age and $64.82{\pm}6.77$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After two capsules containing 100 mg as acebrophylline were orally administered, blood was taken at predetermined time intervals and the concentrations of ambroxol in serum were determined using HPLC with electrochemical detector (ECD). The dissolution profiles of two formulations were similar at all dissolution media. In addition, the pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug Surfolase, were -1.64, -3.33 and -0.92% for $AUC_t$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log 0.8 to log 1.25 $(e.g., \;log\;0.93{\sim}log\;1.05\;and\;log\;0.88{\sim}log\;1.05$ for $AUC_t$, and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Burophil capsule was bioequivalent to Surfolase capsule.

The Survey on Pesticide Residues in Vegetables Collected In Seoul (서울지역 유통 채소류의 잔류농약 조사)

  • Jang, Mi-Ra;Moon, Hyun-Kyung;Kim, Tae-Rang;Yuk, Dong-Hyun;Kim, Eun-Hee;Hong, Chae-Kyu;Choi, Chae-Man;Hwang, In-Sook;Kim, Jung-Hun;Kim, Moo-Sang
    • The Korean Journal of Pesticide Science
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    • v.15 no.2
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    • pp.114-124
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    • 2011
  • The characteristics of pesticide residues by multiresidue analysis method using GC, HPLC and GC-MSD were examined for 18,069 numbers of 91 kinds of vegetables in Seoul from 2007 to 2009. Detection rates of pesticide residues were 11.2% in 2007, 8.5% in 2008 and 12.0% in 2009, respectively, and the excess rates of Maximum Residue Limits (MRLs) showed a declining tendency as 4.6% in 2007, 2.8% in 2008 and 2.1% in 2009, respectively. The pesticides exceeding MRLs were 43 ingredients in 2007, 30 ingredients in 2008 and 36 ingredients in 2009, respectively. The frequencies of pesticides exceeding MRLs were 71 of azoxystrobin in 2007, 29 of procymidone in 2008, 24 of endosulfan in 2009, respectively. The excess rate of mustard green for MRLs in comparison with sample numbers was the highest among vegetables analyzed more than 10 cases each year. As a result of comparing annually pesticide residues about pesticide ingredients showed high frequency rates for pesticide detection, there was a statistical significance for the detection quantities of diazinon, endosulfan, paclobutrazol and procymidone.

Functional Activities of Cacao Nibs and Couvertures according to Process Conditions (카카오닙과 커버춰의 가공 조건에 따른 기능성 분석)

  • Choi, Soo-Young;Son, Yang-Ju;Yoo, Kyung-Mi;Lee, Ki-Won;Hwang, In-Kyeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.1
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    • pp.68-75
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    • 2016
  • This study was conducted to provide information regarding changes in antioxidant activity in response to conching temperatures, conching times, and cacao mass content (CMC) in dark chocolate. The radical scavenging activities and functional components of cacao nibs were highest for raw cacao nib (R0) under all conditions. Moreover, antioxidant activities and functional compounds increased during roasting for 25 min. As the conching temperature increased, the radical scavenging activities and functional components increased. Quantitative analysis of major catechin-derived compounds by HPLC revealed that R0 had the highest value for other roasted cacao nibs in all aspects (P<0.05). The content of procyanidin B2, catechin, and epicatechin increased during roasting for 25 min. Finally, evaluation of couvertures revealed that procyanidin B1 content increased as conching time increased to 48 h, except for 70% CMC and conched at $60^{\circ}C$ (HH) and 70% CMC and conched at $50^{\circ}C$. Overall, HH48 contained the richest catechin-derived components.

Convenient Method for Selective Isolation of Immuno-Stimulating Polysaccharides from Persimmon Leaves (감잎으로부터 면역 활성 다당의 선택 분리를 위한 간편 방법)

  • Lee, Sue Jung;Hong, Hee-Do;Shin, Kwang-Soon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.1
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    • pp.52-60
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    • 2016
  • The biological activity of polysaccharide is greatly influenced by polysaccharide structure and molecular distribution. Here, we developed a rapid and convenient isolation method for fractionating polysaccharides with different characteristics and optimized it using a polysaccharide mixture from Korean persimmon leaves. A crude polysaccharide mixture, persimmon leaves-enzyme (PLE) fraction, was isolated from persimmon leaves digested with pectinase and ethanol precipitation. The PLE fraction was further fractionated with a serially diluted ethanol solution (ethanol : deionized water=4:1, 2:1, 1.5:1, 1:1, and 0.5:1) to produce 10 subfractions (five precipitate fractions labeled from PLE-4 to PLE-0.5 and five supernatant fractions labeled from PLE-4S to PLE-0.5S). HPLC analysis indicated that PLE-4 and -2 consisted of diverse polysaccharides, whereas PLE-1.5, -1, and -0.5 contained high molecular weight (MW) polysaccharides. The fractions from PLE-4 to PLE-1 were mostly composed of 13 different characteristic sugars in rhamnogalacturonan (RG) I and II, and the sugars contained an arabino-${\beta}$-3,6-galactan moiety. However, PLE-0.5 did not contain RG-II or ${\beta}$-arabino-3,6-galactan. Treatment of macrophages with fractions PLE-1.5S and PLE-1S led to a $10{\mu}g/mL$ increase in interleukin (IL)-6 production, whereas treatment with PLE-4S and PLE-2S fractions composed of low MW polysaccharides resulted in reduced levels of IL-6. These results indicate that this isolation method may be useful for the rapid and convenient fractionation of bioactive RGs from polysaccharide mixtures with various properties.

Effects of Pre Harvest Light Treatments (LEDs, Fluorescent Lamp, UV-C) on Glucosinolate Contents in Rocket Salad (Eruca sativa) (수확 전 LED, 형광등, UV-C 조사가 로켓 샐러드 내 글루코시놀레이트 함량에 미치는 영향)

  • Lee, Hye-Jin;Chun, Jin-Hyuk;Kim, Sun-Ju
    • Horticultural Science & Technology
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    • v.35 no.2
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    • pp.178-187
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    • 2017
  • The aim of this study was to investigate the effect of different light sources on the levels of glucosinolates (GSLs) in rocket salad (Eruca sativa L.). The light sources used in the study were: natural light (Control-1 or 2), red light-emitting diodes(LEDs), blue LEDs, mixed red and blue LEDs (R+B LEDs), white LEDs, fluorescent lamps (FL), and fluorescent lamps plus UV-C (FL+UV-C). Two separate experiments were conducted [Experiment I: Control-1, Red LED, Blue LED, Mix (R+B) LED and Experiment II: Control-2, White LED, FL, FL+UV-C] because of the limited number of growth chambers in our laboratory. The rate of increase in the length of rocket salad leaves was the highest under red LEDs and, FL confirming that red LED and, FL affect the growth of rocket salad. We separated and identified seven types of GSLs from the rocket salad:glucoraphanin, diglucothiobeinin, glucoerucin, glucobrassicin, dimeric 4-mercaptobutyl GSL, 4-methoxyglucobrassicin, and gluconasturtiin. The highest total GSL contents in Eexperiment I was found in plants grown under in red LEDs ($4.30{\mu}mol{\cdot}g^{-1}\;dry$ weight, DW), and the lowest under blue LEDs ($0.17{\mu}mol{\cdot}g^{-1}\;DW$). The highest total GSL contents in Experiment II was found in plants grown under FL ($13.45{\mu}mol{\cdot}g^{-1}\;DW$), and the lowest in FL+UV-C ($0.39{\mu}mol{\cdot}g^{-1}\;DW$). Especially in Experiment II, the content of dimeric 4-mercaptobutyl, which has a strong aroma and spicy flavor in rocket salad, was higher under FL and white LEDs than in Control-2, increasing by approximately 14.9 and 3.2-fold respectively. Therefore, light sources such as red LEDs, white LEDs and FL affected the accumulation of GSLs in rocket salad.

Analysis of Functional Constituents of Mulberries (Morus alba L.) Cultivated in a Greenhouse and Open Field during Maturation (시설 및 노지 재배 오디의 숙기에 따른 기능성 성분 함량 분석)

  • Kim, Ha Yun;Lee, Ji Young;Hwang, In Guk;Han, Hye Min;Park, Bo Ram;Han, Gui Jung;Park, Jong Tae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.10
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    • pp.1588-1593
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    • 2015
  • Contents of phenolic acids, flavonoids, and anthocyanins of mulberries (Morus alba L.) cultivated in a greenhouse (GH) and open field (OF) were evaluated by HPLC during maturation. In the case of phenolic acids, caffeic acid ($96.37{\sim}824.00{\mu}g/g$), coumaric acid ($19.45{\sim}68.23{\mu}g/g$), ferulic acid ($4.50{\sim}18.66{\mu}g/g$), and sinapic acid ($15.61{\sim}29.27{\mu}g/g$) were detected. The major phenolic acid was caffeic acid, and its content increased in the initial stage and decreased in the last stage. The phenolic acid content of OF mulberries was higher than that of GH mulberries. Contents of two major flavonoids, quercetin, and kaempferol, were $44.17{\sim}1,661.73{\mu}g/g$ and $108.67{\sim}360.20{\mu}g/g$, respectively. Quercetin content decreased with maturation stage, whereas kaempferol content remained constant in GH mulberries but increased in OF mulberries. In the case of cultivation methods, quercetin content of OF mulberries was higher than that of GH mulberries. Contents of cyanidin, delphinidin, malvidin, and pelargonidin were $30.43{\sim}6,443.88{\mu}g/g$, $0{\sim}52.10{\mu}g/g$, $1.06{\sim}1,650{\mu}g/g$, and $1.92{\sim}401.97{\mu}g/g$, respectively. Anthocyanin content increased with maturation stage, and anthocyanin content of OF mulberries was higher than that of GH mulberries. OF mulberries in the last stage of maturation had higher contents of functional substances than other conditions.

Antioxidative, and Inhibitory Activities on Melanogenesis of Vitex negundo L. Leaf Extract (목형 잎 추출물의 항산화 활성과 멜라닌 생합성에 대한 저해활성)

  • Kim, A Reum;Park, Su Ah;Ha, Ji Hoon;Park, Soo Nam
    • Microbiology and Biotechnology Letters
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    • v.41 no.1
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    • pp.135-144
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    • 2013
  • The aim of this study was to evaluate various aspects of Vitex negundo L. leaf extract, such as the antioxidative activity, tyrosinase inhibitory effects, and inhibitory activities on ${\alpha}$-MSH induced melanogenesis, and active component analysis. The DPPH (1, 1-diphenyl-2-picrylhydrazyl) scavenging activities ($FSC_{50}$) of the ethyl acetate fraction and aglycone fraction of V. negundo L. leaf extract were $14.51{\mu}g/ml$ and $13.96{\mu}g/ml$, respectively. A luminol-dependent chemiluminescence assay revealed that the reactive oxygen species (ROS) scavenging activity ($OSC_{50}$) of the aglycone fraction of V. negundo L. leaf extract on ROS generated in an $Fe^{3+}$-$EDTA/H_2O_2$ system was the most prominent at $0.22{\mu}g/ml$. The protective effects of the extracts fractions of V. negundo L. leaf against the rose-bengal sensitized photohemolysis of human erythrocytes were increased in a concentration dependent manner ($1{\sim}50{\mu}g/ml$). In particular, there were greater protective effects of the aglycone fraction on the cellular membrane than that of the fat-soluble antioxidant (+)-${\alpha}$-tocopherol. The inhibitory effects ($IC_{50}$) on mushroom tyrosinase were the highest for the ethyl acetate fraction ($IC_{50}$ = $48.58{\mu}g/ml$). The inhibitory effect on ${\alpha}$-MSH induced melanogenesis in B16 melanoma cells was 41.80% at $50{\mu}g/ml$ of ethyl acetate fraction. Active component analyses by TLC, HPLC and LC/ESI-MS revealed luteolin and isoorientin. These results indicate that V. negundo L. leaf extract can be used as an antioxidant for ROS scavenging. Particularly, the luteolin and isoorientin of the ethyl acetate fraction may be applicable to new whitening cosmetics because of its inhibitory effect on mushroom tyrosinase and ${\alpha}$-MSH induced melanogenesis in B16 melanoma cells.