• Title/Summary/Keyword: Quantification Method

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Characterizing a full spectrum of physico-chemical properties of (20S)-and (20R)-ginsenoside Rg3 to be proposed as standard reference materials

  • Kim, Il-Woung;Sun, Won Suk;Yun, Bong-Sik;Kim, Na-Ri;Min, Dongsun;Kim, Si-Kwan
    • Journal of Ginseng Research
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    • v.37 no.1
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    • pp.124-134
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    • 2013
  • The authentication of the physico-chemical properties of ginsenosides reference materials as well as qualitative and quantitative batch analytical data based on validated analytical procedures is a prerequisite for certifying good manufacturing practice (GMP). Ginsenoside Rb1 and Rg1, representing protopanaxadiol and protopanaxatriol ginsenosides, respectively, are accepted as marker substances in quality control standards worldwide. However, the current analytical methods for these two compounds recommended by Korean, Chinese, European, and Japanese pharmacopoeia do not apply to red ginseng preparations, particularly the extract, because of the relatively low content of the two agents in red ginseng compared to white ginseng. In manufacturing fresh ginseng into red ginseng products, ginseng roots are exposed to a high temperature for many hours, and the naturally occurring ginsenoside Rb1 and Rg1 are converted to artifact ginsenosides such as Rg3, Rg5, Rh1, and Rh2 during the heating process. The analysis of ginsenosides in commercially available ginseng products in Korea led us to propose the inclusion of the (20S)- and (20R)-ginsenoside Rg3, including ginsenoside Rb1 and Rg1, as additional reference materials for ginseng preparations. (20S)- and (20R)-ginsenoside Rg3 were isolated by Diaion HP-20 adsorption chromatography, silica gel flash chromatography, recrystallization, and preparative HPLC. HPLC fractions corresponding to those two ginsenosides were recrystallized in appropriate solvents for the analysis of physico-chemical properties. Documentation of those isolated ginsenosides was achieved according to the method proposed by Gaedcke and Steinhoff. The ginsenosides were subjected to analyses of their general characteristics, identification, purity, content quantification, and mass balance tests. The isolated ginsenosides showed 100% purity when determined by the three HPLC systems. Also, the water content was found to be 0.534% for (20S)-Rg3 and 0.920% for (20R)-Rg3, meaning that the net mass balances for (20S)-Rg3 and (20R)-Rg3 were 99.466% and 99.080%, respectively. From these results, we could assess and propose a full spectrum of physico-chemical properties of (20S)- and (20R)-ginsenoside Rg3 as standard reference materials for GMP-based quality control.

True Retention and β-Carotene Contents in 22 Blanched Vegetables (데치기(Blanching)로 조리된 22가지 채소류의 베타카로틴 함량의 변화와 영양소 보존율(True Retention))

  • Hwang, Keum-Hee;Shin, Jung-Ah;Lee, Ki-Teak
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.7
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    • pp.990-995
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    • 2016
  • In the present study, reversed-phase HPLC was utilized to quantify the ${\beta}$-carotene content of 22 kinds of raw and blanched vegetables consumed in Korea. In addition, true retention (TR) of ${\beta}$-carotene in samples was obtained. For quantification of ${\beta}$-carotene, external standard curve was obtained with limit of detection and limit of quantitation. The ${\beta}$-carotene contents in 22 raw vegetables ranged from 6.29 (bellflower root) to $7,050.73{\mu}g/100g$ (spinach, field culture). After blanching, ${\beta}$-carotene contents of 13 vegetables increased up to 103.05% while nine vegetables resulted in reduced content, ranging from -2.17 to -29.16%. However, even though increased ${\beta}$-carotene content was observed after blanching, TR of some vegetables was lower than 100% due to their weight reduction. The highest TR of ${\beta}$-carotene was found from blanched cabbage (164.46%) while the lowest TR was found from Turcz (Gomchwi) at 59.35%. TR is an effective method to evaluate retention of nutrients in cooked foods, considering changes of nutrient content and weight.

Analysis Method for Non-Linear Finite Strain Consolidation for Soft Dredged Soil Deposit -Part I: Parameter Estimation for Analysis (초연약 준설 매립지반의 비선형 유한변형 압밀해석기법 -Part I: 해석 물성치 평가)

  • Kwak, Tae-Hoon;Lee, Chul-Ho;Lim, Jee-Hee;An, Yong-Hoon;Choi, Hang-Seok
    • Journal of the Korean Geotechnical Society
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    • v.27 no.9
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    • pp.13-24
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    • 2011
  • The renowned Terzaghi's one-dimensional consolidation theory is not applicable to quantification of time-rate settlement for highly deformable soft clays such as dredged soil deposits. To deal with this special condition, a non-linear finite strain consolidation theory should be adopted to predict the settlement of dredged soil deposits including self-weight and surcharge-induced consolidation. It is of importance to determine the zero effective stress void ratio ($e_{00}$), which is the void ratio at effective stress equal to zero, and the relationships of void ratio-effective stress and of void ratio-hydraulic conductivity for characterizing non-linear finite strain consolidation behavior for deformable dredged soil deposits. The zero effective stress void ratio means a transitional status from sedimentation to self-weight consolidation of dredged soils. In this paper, laboratory procedures and equipments are introduced to measure such key parameters in the non-linear finite strain consolidation analysis. In addition, the non-linear finite strain consolidation parameters of the Incheon clay and kaolinite are evaluated with the aid of the proposed methods in this paper, which will be used as input parameters for the non-linear finite strain consolidation analyses being performed in the companion paper.

Placenta Transfer and Toxicokinetics of Valproic Acid in Pregnant Cynomolgus Monkeys

  • Jeong, Eun-Ju;Yu, Wook-Joon;Kim, Choong-Yong;Chung, Moon-Koo
    • Toxicological Research
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    • v.26 no.4
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    • pp.275-283
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    • 2010
  • Placenta transfer study in non-human primate (NHP) is one of the crucial components in the assessment of developmental toxicity because of the similarity between NHP and humans. To establish the method to determine placenta transfer in non-human primate, toxicokinetics of valproic acid (VPA), a drug used to treat epilepsy in pregnant women, were determined in pregnant cynomolgus monkeys. After mating, pregnancy-proven females were daily administered with VPA at dose levels of 0, 20, 60 and 180 mg/kg by oral route during the organogenesis period from gestation day (GD) 20 to 50. Concentrations of VPA and its metabolite, 4-ene-VPA, in maternal plasma on GDs 20 and 50, and concentrations of VPA and 4-ene-VPA in placenta, amniotic fluid and fetus on GD 50 were analyzed using LC/MS/MS. Following single oral administration of VPA to pregnant monkeys, concentrations of VPA and 4-ene-VPA were generally quantifiable in the plasma from all treatment groups up to 4-24 hours post-dose, demonstrating that VPA was absorbed and the monkeys were systemically exposed to VPA and 4-ene-VPA. After repeated administration of VPA to the monkeys, VPA was detected in amniotic fluid, placenta and fetus from all treatment groups, demonstrating that VPA was transferred via placenta and the fetus was exposed to VPA, and the exposures were increased with increasing dose. Concentrations of 4-ene-VPA in amniotic fluid and fetus were below the limit of quantification, but small amount of 4-ene-VPA was detected in placenta. In conclusion, pregnant monkeys were exposed to VPA and 4-ene-VPA after oral administration of VPA at dose levels of 20, 60 and 180 mg/kg during the organogenesis period. VPA was transferred via placenta and the fetus was exposed to VPA with dose-dependent exposure. The metabolite, 4-ene VPA, was not detected in both amniotic fluid and fetus, but small amount of 4-ene-VPA was detected in placenta. These results demonstrated that proper procedures to investigate placenta transfer in NHP, such as mating and diagnosis of pregnancy via examining gestational sac with ultrasonography, collection of amniotic fluid, placenta and fetus after Caesarean section followed by adequate bioanalysis and toxicokinetic analysis, were established in this study using cynomolugus monkeys.

Magnetic Flux Leakage based Damage Quantification of Steel Bar (누설자속기법을 이용한 강봉의 손상 정량화 기법)

  • Park, Jooyoung;Kim, Ju-Won;Yu, Byoungjoon;Park, Seunghee
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.30 no.1
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    • pp.63-70
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    • 2017
  • In this paper, a magnetic flux leakage(MFL) based steel bar damage detection was first researched to quantify the signals from damages on the wire rope. Though many researches inspecting damages using a MFL method was proceeded until the present, the researches are at the level that diagnose whether damages are or not. This has limitation to take measures in accordance with the damage level. Thus, a MFL inspection system was modeled using a finite element analysis(FEM) program dealing with electromagnetism problems, and a steel bar specimen was adopted as a ferromagnetic object. Then, an experimental study was also carried out to verify the simulation results with a steel bar which has same damage conditions as the simulation. The MFL signals was nearly not affected by the increase of the inspection velocity, and the magnitudes of the signals are not identical according to the change of the defect width even the defects have same depth. On the basis of the analysis, the signal properties from the damages were extracted to classify the type of damages, and it could be confirmed that classification of damages using extracted signal properties is feasible.

The Environmental Hazard Assessment of Siting Restricted Industries from Industrial Complex in Rural Area Applied by Chemical Ranking and Scoring System (화학적 등급화기법을 적용한 농공단지 입주제한업종의 환경유해성 평가)

  • Hong, Sang-Pyo
    • Journal of Environmental Impact Assessment
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    • v.24 no.6
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    • pp.549-560
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    • 2015
  • The priorities of siting restriction was derived from quantification of environmental hazard according to industrial classification based on 'Chemical Ranking and Scoring System(CRS)' which is handling the discharge characteristics of 31 industrial classifications regulated from locating at 'Industrial Complex in Rural Area(ICRA)'. CRS that is utilizing the data of 'Pollutant Release and Transfer Registers(PRTR)' is applied to determine human health risk and ecological risk which are calculated by discharged amount and materials $LC_{50}$ according to water, soil and air media based on industrial classification. From this process, exposure assessment and toxicity assessment for integrating the adverse environmental impact and the mitigation effect of environmental risk according to the development of environmental technologies into establishing the rational landuse management method for the 31 industrial classifications regulated from locating at ICRA was analyzed. From the assessment result of the siting restriction removal at ICRA for 31 industrial classifications, based on 2012 year reference 6 industries that includes Manufacture of Guilt Coloration Surface Processing Steel Materials, Manufacture of Biological Product, Manufacture of Smelting Refining and Alloys of Copper, Dyeing and Finishing of Fibers and Yarns, Manufacture of Other Basic Iron and Steel n.e.c., Rolling Drawing and Extruding of Non-ferrous Metals n.e.c. are calculated as having relatively lower environmental hazards, thus it is judged that the siting restriction mitigation at ICRA is possible for the 6 industrial classifications that are not discharging the specific hazardous water contaminants during manufacturing process.

Optimal Echo phase of FLASH sequence for Brain Enhancement scan of mouse at 9.4T MRI system (9.4T MRI FLASH Sequence에서 마우스의 뇌 조영증강 검사를 위한 적정 Echo phase)

  • Jeong, Hyunkeun;Kim, Mingi;Nam, Kichang;Jung, Hyundo;Ahn, Chigwon;Kim, Hochul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.7
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    • pp.115-124
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    • 2017
  • The objective of study was to investigate the optimal echo phase for mouse brain enhancement scan using fast low angle shot (FLASH) sequence of 9.4T magnetic resonance imaging (MRI). For quantification based on this method, an MR phantom experiment and clinical research were done. The phantom experiment was conducted by fabricating three phantoms with different molar concentration of gadolinium to create changes in echo phase of 9.4T FLASH sequence used in mouse brain scans. In the phantom experiment, SSI was 25~27 [arbitrary units, a.u.] in each of 33 phases from $6{\pi}$ to $28{\pi}$, while RSP was 30~100 mmol. MPSI was 47~52 [a.u], while MPP, where MPSI is seen, was 0.8~9 mmol. EPMS was 80.8~108.0%, while ASIMP was formed between 21.1 and 31.8 [a.u]. In the clinical research, Finally, the occurrence rate of artifact that expressed -1 nd +1. The present study was able to quantify the degree of enhancement at FLASH sequence of 9.4T MRI, as well as identify the optimal echo phase during mouse brain enhancement scan.

Methyl Donor Status Influences DNMT Expression and Global DNA Methylation in Cervical Cancer Cells

  • Poomipark, Natwadee;Flatley, Janet E;Hill, Marilyn H;Mangnall, Barbara;Azar, Elnaz;Grabowski, Peter;Powers, Hilary J
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.7
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    • pp.3213-3222
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    • 2016
  • Background: Methyl donor status influences DNA stability and DNA methylation although little is known about effects on DNA methyltransferases. The aim of this study was to determine whether methyl-donor status influences DNA methyltransferase (Dnmt) gene expression in cervical cancer cells, and if so, whether there are associated effects on global DNA methylation. Materials and Methods: The human cervical cancer cell line, C4-II, was grown in complete medium and medium depleted of folate (F-M+) and folate and methionine (F-M-). Growth rate, intracellular folate, intracellular methionine and homocysteine in the extracellular medium were measured to validate the cancer cell model of methyl donor depletion. Dnmt expression was measured by qRT-PCR using relative quantification and global DNA methylation was measured using a flow cytometric method. Results: Intracellular folate and methionine concentrations were significantly reduced after growth in depleted media. Growth rate was also reduced in response to methyl donor depletion. Extracellular homocysteine was raised compared with controls, indicating disturbance to the methyl cycle. Combined folate and methionine depletion led to a significant down-regulation of Dnmt3a and Dnmt3b; this was associated with an 18% reduction in global DNA methylation compared with controls. Effects of folate and methionine depletion on Dnmt3a and 3b expression were reversed by transferring depleted cells to complete medium. Conclusions: Methyl donor status can evidently influence expression of Dnmts in cervical cancer cells, which is associated with DNA global hypomethylation. Effects on Dnmt expression are reversible, suggesting reversible modulating effects of dietary methyl donor intake on gene expression, which may be relevant for cancer progression.

Effect of Cooking Methods on S-Allyl-L-Cysteine Content of Garlic (마늘의 조리방법에 따른 S-Allyl-L-Cysteine 함량 변화)

  • Lee, Sang Hoon;Jeong, Yun Sook;Hwang, Kyung-A;Song, Jin;Noh, Geon Min;Hwang, In Guk
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.8
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    • pp.1221-1226
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    • 2016
  • This study investigated changes in the S-allyl-L-cysteine (SAC) content of garlic using different cooking methods. Methods for determining SAC were validated by determining specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy using an high-performance liquid chromatography-fluorescence detection system. Results showed high linearity in the calibration curve with a coefficient of correlation ($R^2$) of 0.9999. The LOD and LOQ values for SAC were 0.15 and $0.47{\mu}g/mL$, respectively. The relative standard deviations for intra- and inter-day precision of SAC were less than 5%. The recovery rate of SAC was in the range from 97.35% to 97.47%. The SAC content of raw garlic was 2.77 mg/g, and there was no significant difference in SAC content according to blanching and microwave treatment. However, SAC content upon boiling and autoclaving at $110^{\circ}C$ and $121^{\circ}C$ increased from 3.50~9.16 mg/g, 6.52~16.21 mg/g, and 14.15~50.24 mg/g with increasing cooking temperature and time, respectively.

CONSTRUCTION OF HNGF-$\beta$ RECOMBINANT ADENOVIRUS & SCREENING OF ITS EXPRESSION AFTER TRANSFECTION INTO VARIOUS CELL LINES (말초신경재생을 위한 hNGF-$\beta$ recombinant Adenovirus의 제작 및 수종세포주에서 신경성장인자의 발현)

  • Gao, En-Feng;Chung, Hun-Jong;Ahn, Kang-Min;Kim, Yoon-Tae;Park, Hee-Jung;Sung, Mi-Ae;Kim, Nam-Yeol;Yoo, Sang-Bae;Myoung, Hoon;Hwang, Soon-Jung;Kim, Myung-Jin;Kim, Sung-Min;Jang, Jeong-Won;Lee, Jong-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.27 no.5
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    • pp.446-456
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    • 2005
  • Nerve growth factor(NGF) has a critical role in peripheral nerve regeneration. The aim of this study is to construct a well-functioning hNGF-$\beta$ recombinat adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with adenovirus mediated hNGF-$\beta$ gene transfection into Schwann cells. First PCR associated cloning of GFP-tagged hNGF-$\beta$ which was ligated into E1/E3 deleted adenoviral vector was performed and tranfected into E. coli to construct hNGF-$\beta$ recombinant adenovirus. After production of recombinat adenovirus in a large scale, its transfection efficiency, expression, and function were evaluated using cell lines or primarily cultured cells of HEK293 cells, Schwann cells, fibroblast(NIH3T3) and myocyte(CRH cells). GFP expression was observed in 90% of infected cells compared to uninfected cells. Total mRNA isolated from hNGF-$\beta$ recombinat adenoviru infected cells showed strong RT-PCR band, however, LacZ recombinant adenovirus infected or uninfected cells did not. NGF quantification by ELISA showed a maximal release of 18.865 +/- 0.31ng/mL at 4th day. PC-12 cells exposed to media with hNGF-$\beta$ recombinant adenovirus infected Schwann cell demonstrated higher levels of differentiation compared with controls. We generated hNGF-$\beta$ recombinant adenovirus and induced over expression of NGF successfully in nonneuronal and neuronal cells. Following these result, it is expected to develop an improved treatment strategy peripheral nerve regeneration using the hNGF-$\beta$ gene transfected cells.