Korea Food and Drug Administration
Korea Food and Drug Administration
Lee H.,Ewha Womans University |
Oh Y.J.,Korea National University of Transportation |
Cho I.H.,Central Research Institute Shinpoong Pharm. Co. |
Lee H.,KAIST |
And 2 more authors.
Chemical Communications | Year: 2012
A new way is demonstrated to develop a bio-inspired coacervate hydrogel by following catechol chemistry showing injectable and re-moldable physical properties. The formed coacervate shows potential long-term stability under water. Depending on pH, formation of the coacervate has been verified which is confirmed by XPS and zeta potential measurements. © 2012 The Royal Society of Chemistry.
Cho H.Y.,Korea Food and Drug Administration |
Yoo H.D.,Chonnam National University |
Lee Y.B.,Chonnam National University
Neuroscience | Year: 2010
The purposes of this study were to clarify the involvement of P-glycoprotein in the absorption of levosulpiride in knockout mice that lack the Abcb1a/ 1b gene, and to evaluate the relationship between genetic polymorphisms in ABCB1 (exon 12, 21 and 26) and levosulpiride disposition in healthy subjects. The plasma and brain samples were obtained after oral administration (10 μg/g) of levosulpiride to abcb1a/1b(-/-) and wild-type mice (n=3~6 at each time point). The average brain-to-plasma concentration ratio and blood-brain barrier partitioning of levosulpiride were 2.3- and 2.0-fold higher in Abcb1a/1b(-/-) mice than in wild-type mice, respectively. A total of 58 healthy Korean volunteers receiving a single oral dose of 25 mg levosulpiride participated in this study. The subjects were evaluated for polymorphisms of the ABCB1 exon 12 C1236T, exon 21 G2677A/T (Ala893Ser/Thr) and exon 26 C3435T using polymerase chain reaction restriction fragment length polymorphism. The PK parameters (AUC0-4h, AUC0-∞ and Cmax.) of ABCB1 2677TT and 3435TT subjects were significantly higher than those of subjects with at least one wild-type allele (P<0.05). The results indicate that levosulpiride is a P-glycoprotein substrate in vivo, which is supported by the effects of SNPs 2677G>A/T in exon 21 and 3435C>T in exon 26 of ABCB1 on levosulpiride disposition. © 2010 IBRO.
Yoo H.-D.,Chonnam National University |
Cho H.-Y.,Korea Food and Drug Administration |
Lee Y.-B.,Chonnam National University
British Journal of Clinical Pharmacology | Year: 2010
Aims To investigate the influence of genetic polymorphisms in the CYP3A5, CYP2C19 and ABCB1 genes on the population pharmacokinetics of cilostazol in healthy subjects. Methods Subjects who participated in four separate cilostazol bioequivalence studies with the same protocols were included in this retrospective analysis. One hundred and four healthy Korean volunteers were orally administered a single 50- or 100-mg dose of cilostazol. We estimated the population pharmacokinetics of cilostazol using a nonlinear mixed effects modelling (nonmem) method and explored the possible influence of genetic polymorphisms in CYP3A (CYP3A5*3), CYP2C19 (CYP2C19*2 and CYP2C19*3) and ABCB1 (C1236T, G2677T/A and C3435T) on the population pharmacokinetics of cilostazol. Results A two-compartment model with a first-order absorption and lag time described the cilostazol serum concentrations well. The apparent oral clearance (CL/F) was estimated to be 12.8 l h-1. The volumes of the central and the peripheral compartment were characterized as 20.5 l and 73.1 l, respectively. Intercompartmental clearance was estimated at 5.6 l h-1. Absorption rate constant was estimated at 0.24 h-1 and lag time was predicted at 0.57 h. The genetic polymorphisms of CYP3A5 had a significant (P < 0.001) influence on the CL/F of cilostazol. When CYP2C19 was evaluated, a significant difference (P < 0.01) was observed among the three genotypes (extensive metabolizers, intermediate metabolizers and poor metabolizers) for the CL/F. In addition, a combination of CYP3A5 and CYP2C19 genotypes was found to be associated with a significant difference (P < 0.005) in the CL/F. When including these genotypes, the interindividual variability of the CL/F was reduced from 34.1% in the base model to 27.3% in the final model. However, no significant differences between the ABCB1 genotypes and cilostazol pharmacokinetic parameters were observed. Conclusions The results of the present study indicate that CYP3A5 and CYP2C19 polymorphisms explain the substantial interindividual variability that occurs in the metabolism of cilostazol. © 2010 The Authors. Journal compilation © 2010 The British Pharmacological Society.
Lee H.-M.,Seoul National University |
Kim C.S.,Korea Food and Drug Administration |
Jang Y.M.,Korea Food and Drug Administration |
Kwon S.W.,Seoul National University |
Lee B.-J.,Seoul National University
Journal of Pharmaceutical and Biomedical Analysis | Year: 2011
MEGATON, a dietary supplement, was analyzed in order to detect PDE-5 inhibitors and their analogues. A new analogue of vardenafil could be detected by high-performance liquid chromatography (HPLC) analysis with a photodiode array detector (PDA). This compound was compared with sildenafil, tadalafil, and vardenafil as well as their structurally modified analogues such as hongdenafil and homosildenafil. The structure of this compound was elucidated by mass spectrometry (MS), infrared (IR) spectroscopy and one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. When compared with vardenafil to verify the structural difference, this compound had an acetyl group instead of a sulfonyl group in the pyrazolopyrimidine portion without any substitution in the piperazine ring of the molecule. This compound was identified as 2-(2-ethoxy-5-(2-(4-ethylpiperazin-1-yl)acetyl)phenyl)-5-methyl-7-propyl-imidazo(5,1-f)-(1,2,4)triazin-4(3H)-one, which is also called acetylvardenafil. © 2010 Elsevier B.V.
Aditya N.P.,Sejong University |
Shim M.,Sejong University |
Lee I.,Sejong University |
Lee Y.,Sejong University |
And 2 more authors.
Journal of Agricultural and Food Chemistry | Year: 2013
To increase the oral bioavailability of curcumin and genistein, we fabricated nanostructured lipid carriers (NLCs), and the impact of these carriers on bioaccessibility of curcumin and genistein was studied. Entrapment efficiency was more than 75% for curcumin and/or genistein-loaded NLCs. Solubility of curcumin and/or genistein in simulated intestinal medium (SIM) was >75% after encapsulating within NLCs which otherwise was <20%. Both curcumin and genistein have shown good stability (≥85%) in SIM and simulated gastric medium (SGM) up to 6 h. Coloading of curcumin and genistein had no adverse effect on solubility and stability of each molecule. Instead, coloading increased loading efficiency and the cell growth inhibition in prostate cancer cells. Collectively, these results have shown that coloaded lipid based carriers are promising vehicles for oral delivery of poorly bioaccessible molecules like curcumin and genistein. © 2013 American Chemical Society.
Na S.,Korea Institute of Science and Technology |
Kim M.,Korea Food and Drug Administration |
Paek O.,Korea Food and Drug Administration |
Kim Y.,Korea Institute of Science and Technology
Chemosphere | Year: 2013
This study was conducted to measure the concentration of PBDEs in various food stuffs from Korea and to estimate levels of PBDE intake from food for the Korean population according to geographical location and age. 20 types of food samples were collected from four heavily populated cities (Seoul, Gwangju, Daejeon, Pusan) and one rural city (Gangneung) and were analyzed for 19 polybrominated diphenyl ether congeners (BDE 15, 17, 28, 33, 47, 49, 66, 71, 85, 99, 100, 119, 126, 138, 153, 154, 183, and 209).No significant differences in total PBDE levels in foods were found among four large cities (Gwangju; 10.91ngg-1 wet weight (ww), Seoul; 7.66ngg-1ww, Daejeon; 6.91ngg-1ww, Pusan; 6.87ngg-1ww) and one rural city (Gangneung; 8.72ngg-1ww). Daily dietary intake of PBDEs does not appear to be related to the extent of urbanization.Total dietary intake of PBDE for the average general population was 72.30ngd-1 (not detected (ND)=0) which was similar to other countries. In all food groups, the largest contribution to PBDE intake was from fish and shellfish (48.96ngd-1). Total PBDE consumed per kilogram of body weight was estimated to range from 2.70ngkg-1d-1 for infants 1 through 2years of age to 0.85ngkg-1d for 65years and older and was highest in young children and decreased with increasing age. © 2012 Elsevier Ltd.
Kim M.,Korea Food and Drug Administration |
Wolt J.D.,Iowa State University
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2011
Global interest in the adverse health effects of cadmium (Cd) has focused on dietary exposure as the principal source of Cd exposure to the general population. Common assumptions used in deterministic Cd assessment in global or regional diets have limitations when applied to specific national cases where local variation in food composition and consumption patterns are different than for global or regional norms. Stochastic dietary Cd exposure assessment was conducted for the general South Korean population to understand better Cd dietary intake. Because rice (Oryza sativa) is commonly and highly consumed by Koreans, it was the dominant contributor to Cd in the diet, representing on average 25% of the total dietary exposure for the general population. Hazard index (HI) values were below the level of concern for the 95th percentile of the general population. Sensitivity analyses demonstrated that variation in rice intake and Cd concentration had the greatest influence on the Cd risk estimate for the general population. Changes in food sources, such as the use of imported rice with higher Cd levels, would lead to increased Cd exposure in the diet, thus necessitating continued vigilance as to the status of Cd within the food supply. © 2011 Taylor & Francis.
Yong H.-Y.,Duksung Womens University |
Kim I.-Y.,Korea Food and Drug Administration |
Kim J.S.,Duksung Womens University |
Moon A.,Duksung Womens University
International Journal of Oncology | Year: 2010
Overexpression of ErbB2 has been frequently found in mammary carcinoma. We have previously shown that the aberrant activation of H-Ras induces human breast cell invasion and migration. The present study was aimed at investigating the effect of ErbB2 overexpression on H-Ras-induced breast cell invasion and to elucidate the underlying mechanisms. Herein, we show that overexpression of ErbB2 promotes invasive and migratory abilities of H-Ras-activated MCF10A human breast epithelial cells through upregulation of matrix metalloproteinase (MMP)-13 and urokinase-type plasminogen activator (uPA). We also demonstrate that the p38 MAPK is an important signaling molecule in the ErbB2-induced upregulation of MMP-13 and uPA and invasion/migration of H-Ras MCF10A cells overexpressing ErbB2. The present study elucidating the molecular mechanism underlying ErbB2-induced promotion of H-Ras MCF10A cell invasion may provide invaluable information for understanding breast cancer progression and establishing therapeutic interventions for breast cancer.
Lee S.Y.,Korea Food and Drug Administration |
Jung M.Y.,Woosuk University |
Yoon S.H.,Korea Food Research Institute
Food Science and Biotechnology | Year: 2014
Processing conditions during degumming, alkaline refining, bleaching, and deodorization of crude camellia seed oil were optimized to obtain high-quality edible camellia oil. Physicochemical properties of camellia oil were monitored during refining steps. RBD (refined, bleached, and deodorized) camellia oil obtained using optimized refining conditions fully satisfied Korean quality standards for edible oil. The iodine value of camellia oil was 84.2 mg I2/100 g of oil. Camellia oil contained an exceptionally high level of oleic acid (83.1%), along with minor quantities of other fatty acids (8.9% palmitic acid, 4.8% linoleic acid). The total saponin content in crude oil was 437 ppm, as determined by gravimetric analysis. Most (99.8%) of the saponin in crude oil was removed during the refining process. The physicochemical properties of camellia oil were similar to olive oil. RBD camellia oil is virtually colorless and bland tasting and is suitable for edible purposes. © 2014 The Korean Society of Food Science and Technology and Springer Science+Business Media Dordrecht.
Kim E.,Korea Food and Drug Administration |
Bahn K.,Korea Food and Drug Administration |
Kang E.,Korea Food and Drug Administration |
Kim M.,Korea Food and Drug Administration
Food Chemistry | Year: 2012
This study presents the simultaneous extraction and determination of lincomycin (LCM) and narasin (NAR) by using liquid chromatography-electrospray ionisation tandem mass spectrometry (LC-MS/MS) on samples from poultry, milk and eggs (n = 196). The homogenised samples are extracted with acetonitrile and the extract is further cleaned using C 18 solid-phase extraction cartridges. The recoveries of the analytes in different matrices were found ranging from 90% to 101% and 85% to 95% for LCM and NAR, respectively. The corresponding limits of detection were 0.6 and 1.5 ng g -1 for LCM and NAR, respectively. As a result of monitoring, NAR was not detected in any samples and LCM was detected in one egg with a concentration of 25 ng g -1. The method was relatively simple to perform and therefore could be used for food safety surveillance activities. © 2011 Elsevier Ltd. All rights reserved.