• Title/Summary/Keyword: diode detector

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Simultaneous Quantitative Analysis of Major Constituent of Ethanol Extract from Leaves of Helianthus annuus L. (향일규 잎의 에탄올 추출물에 대한 주요 성분 동시 정량분석)

  • Kim, Eun-Nam;Jeon, Sang-Young;Jeong, Gil-Saeng
    • Korean Journal of Pharmacognosy
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    • v.52 no.2
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    • pp.112-117
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    • 2021
  • Helianthus annuus L. has been reported with various pharmacological activities such as antibacterial, antidiabetic, and antioxidant effects. According to recent studies, H. annuus L. is known to contain components such as phenolic compounds, flavonoids, alkaloids, sesquiterpenoids, and lignans. The seeds of H. annuus L. have been reported to contain chlorogenic acid and di-O-caffeoylquinic acid as major components. However, studies on the main components and content of leaves of H. annuus L. are still incomplete. Therefore, in this study, the contents of four major components of H. annuus L. were evaluated by simultaneous quantitative analysis with high performance liquid chromatography (HPLC)-diode array detector (DAD). The isolated four compounds Caffeoylquinic acid(CQA), 3,4-dicaffeoylquinic acid(3,4-DCQA), 3,5-dicaffeoylquinic acid(3,5-DCQA) and 4,5-dicaffeoylquinic acid(4,5-DCQA) were shown in a large linearity with a correlation coefficient (R2) of 0.99. In addition, as a result of intra-inter day analysis of four major compounds by the analysis method of this study, the accuracy of 88.46% or more and less than 112.85% and excellent precision of less than 3% were shown, the content analysis showed CQA (0.383±0.018 mg/g), 3,4-DCQA (0.282±0.017 mg/g), 3,5-DCQA (1.109±0.068 mg/g), and 4,5-DCQA (0.673±0.020 mg/g).

Development and Validation of an HPLC-PDA Method for Quantitation of Ten Marker Compounds from Eclipta prostrata (L.) and Evaluation of Their Protein Tyrosine Phosphatase 1B, α-Glucosidase, and Acetylcholinesterase Inhibitory Activities

  • Nguyen, Duc Hung;Le, Duc Dat;Ma, Eun Sook;Min, Byung Sun;Woo, Mi Hee
    • Natural Product Sciences
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    • v.26 no.4
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    • pp.326-333
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    • 2020
  • The aerial parts of Eclipta prostrata is used as a traditional medicine and vegetable. In traditional folk medicine, it is used for treatment of hemorrhages, hepatic, disease, renal injuries, hair loss, tooth mobility, and viper bites. In this study, ten compounds (1 - 10) were isolated from the aerial parts of E. prostrata. A reliable high performance liquid chromatography equipped with photometric diode array detector (HPLC-PDA) method was developed to simultaneously quantitate 10 marker compounds [chlorogenic acid (1), paratensein 7-O-��-ᴅ-glucoside (2), quercetin 7-O-��-ᴅ-glucoside (3), luteolin 7-O-��-ᴅ-glucoside (4), apigenin 7-O-��-ᴅ-glucoside (5), apigenin 4'-O-��-ᴅ-glucoside (6), apigenin (7), luteolin (8), wedelolactone (9), and paratensein (10)]. In addition, compounds 5 and 6 showed considerable inhibitory effects against protein-tyrosine phosphatase 1B (PTP1B) enzyme. Moreover, compounds 6 - 8, and 10 exhibited potent α-glucosidase inhibitory effects with IC50 values of 24.5 ± 1.9, 33.0 ± 0.5, 45.5 ± 0.1, and 23.8 ± 1.0 µM, respectively. All compounds (1 - 10) showed considerable acetylcholinesterase (AChE) inhibitory effects with IC50 ranging from 30.1 to 75.2 µM.

Chemical influences of the rhizomes of Atractylodes japonica, A. macrocephala, or A. chinensis on the extraction efficiencies of chemical compounds in the roots and rhizomes of Glycyrrhiza uralensis during hot-water extraction (열수추출 과정에서 삽주, 백출(큰꽃삽주), 북창출 배합이 감초 성분의 추출률에 미치는 영향)

  • Kim, Jung-Hoon
    • The Korea Journal of Herbology
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    • v.34 no.5
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    • pp.39-47
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    • 2019
  • Objectives : When herbal medicines are extracted together, they may interact with each other, leading to change of chemical characteristics. This study aimed to evaluate the influence of Atractylodes rhizomes (Atractylodes japonica, A. macrocephala, and A. chinensis) on the chemical features of the roots and rhizomes of Glycyrrhiza uralensis, which is are commonly combined with herbal medicines in many herbal formulae, when they are co-decocted. Methods : Liquiritin apioside, liquiritin, ononin, and glycyrrhizin levels of G. uralensis in hot-water extracts prepared by the combination of Atractylodes rhizomes with various weight ratios (G. uralensis : Atractylodes rhizomes = 10:0, 10:5, 10:10, and 10:20) and extraction times (60, 90, and 120 min) were quantified using a HPLC-diode array detector and compared by statistical analysis. Results : The concentrations of liquiritin apioside, liquiritin, ononin, and glycyrrhizin from G. uralensis roots and rhizomes mostly reduced when co-extracted with Atractylodes rhizomes, and the addition of A. chinensis most reduced their contents between Atractylodes combination groups. A. japonica and A. macrocephala rhizomes also showed differences of liquiritin and glycyrrhizin levels at 10 g and 20 g groups of Atractylodes rhizomes. Extraction times also affected the concentrations of liquiritin, ononin, and glycyrrhizin mostly during 60 and 90 min. Conclusions : Atractylodes rhizomes might alter the chemical characteristics of G. uralensis when these herbs are co-decocted. This study provides the understanding of the chemical interactions of herbal medicines during the extraction in hot water.

Discrimination of biological and artificial nicotine in e-liquid

  • Hyoung-Joon Park;Heesung Moon;Min Kyoung Lee;Min Soo Kim;Seok Heo;Chang-Yong Yoon;Sunyoung Baek
    • Analytical Science and Technology
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    • v.36 no.1
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    • pp.22-31
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    • 2023
  • As the use of e-liquid cigarettes is rapidly increasing worldwide, it multiplies the potential risk undisclosed to the health of non- and smokers. To reduce the hazard, each country has its own set of regulations for controlling e-liquids. In Korea, the narrow definition of tobacco makes it difficult and have been steadily occurring tax evasion exploiting the difference in natural and artificial nicotine. Therefore, it is very important to distinguish source of nicotine for their regulation. To find biochemical discriminant markers, this study established analysis methods based on high-performance liquid chromatography coupled with diode array detector (HPLC-DAD) and high-performance liquid chromatography coupled with triple Quadrupole mass spectrometry (HPLC-MS/MS) for nicotine enantiomers and tobacco alkaloids targeted using the difference in pathways of nicotine biosynthesis and chemical synthesis. The method was validated by experimenting linearity (R2 > 0.999), recovery (80.99-108.41 %), accuracy (94.11-109.73 %) and precision (0.04-8.27 %). Then, the results for discrimination of the nicotine obtained from analysis of 65 commercial e-liquid products available in Korean market was evaluated. The method successfully applied to the e-liquids and one sample labelled 'synthetic nicotine' for tax exemption was found to contain a natural nicotine product. This method can be used to determine whether an e-liquid product uses natural or artificial nicotine and monitor non-taxable e-liquid products. The method is more scientific than the existing one, which relies only on field evidence.

Analysis of Anthocyanin Glycosides in Korean Mulberry Fruit Cultivars (한국산 오디 품종별 안토시아닌 배당체 성분 분석)

  • So Ah Kim;Ryeong Ha Kwon;Ju Hyung Kim;Hyemin Na;Ji Hae Lee;Soo-Muk Cho;Heon-Woong Kim
    • The Korean Journal of Food And Nutrition
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    • v.36 no.6
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    • pp.543-550
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    • 2023
  • Mulberry fruit is a superior source of polyphenols, especially anthocyanin, and has a long history of use as an edible fruit and traditional medicine. The anthocyanin composition of mulberry fruit from 15 Korean cultivars was analyzed by ultra-performance liquid chromatography diode array detector with quadrupole time of flight/mass spectrometry (UPLC-DAD-QToF/MS) based on a cyanin internal standard. The four glycosides were identified by comparison with authentic standards and published reports. The major anthocyanin was cyanidin 3-O-glucoside (71.7%), followed by cyanidin 3-O-rutinoside (26.6%). The minor components (total of 1.7%) were pelargonidin 3-O-glucoside and pelargonidin 3-O-rutinoside. The total anthocyanin content (mg/100 g, dry weight) of mulberry fruit varied by cultivar and ranged from 471.5±4.0 (Su Hong) to 4,700.2±54.0 (Gwa Sang2). Among the 15 cultivars examined, Gwa Sang2 showed the highest level of cyanidin 3-O-glucoside (3,133.4±32.6), which was 9-fold higher than that of Su Hong (351.5±3.4). In conclusion, anthocyanin profiles, including pelargonidin 3-O-glucoside and pelargonidin 3-O-rutinoside, were reported for the first time from 15 Korean mulberry fruit cultivars. The results will contribute valuable information on pharmaceutical properties, breeding superior mulberry cultivars, and food industries.

Study on 6 MV Photon beam Dosimetry by Asymmetric Collimator Variation of Linear Accelerator (6MV 선형가속기의 비대칭 조사야의 변화에 따른 선량분포)

  • Yoon, Joo-Ho;Lee, Chul-Soo;Yum, Ha-Yong
    • The Journal of Korean Society for Radiation Therapy
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    • v.12 no.1
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    • pp.91-104
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    • 2000
  • Recently linear accelerator in radiation therapy in asymmetric field has been easily used since the improvement and capability of asymmetrical field adjustment attached to the machine. It has been thought there have been some significant errors in dose calculation when asymmetrical radiation fields have been utilized in practice of radiation treatments if the fundamental data for dose calculation have been measured in symmetrical standard fields. This study investigated how much the measured data of dose distributions and their isodose curves are different between in asymmetrical and symmetrical standard fields, and how much there difference affect the error in dose calculation in conventional method measured in symmetrical standard field. The distributions of radiation dose were measured by photon diode detector in the water phantom (RFA-300P, Scanditronix, Sweden) as tissue equivalent material on utilization of 6 MV linear accelerator with source surface distance (SSD) 1000 mm. The photon diode detector has the velocity of 1 mm per second from water surface to 250 mm depth in the field size of $40mm{\times}40mm\;to\;250mm{\times}250mm\;symmetric\;field\;and\;40mm{\times}20mm\;to\;250mm{\times}125mm$ asymmetrical fields. The measurements of percent depth dose (PDD) and subsequent plotting of their isodose curves were performed from water surface to 250mm dmm from Y-center axis in $100mm{\times}50mm$ field in order to absence the variability of depth dose according to increasing field sizes and their affects to plotted isodose curves. The difference of PDD between symmetric and asymmetric field was maximum $4.1\%\;decrease\;in\;40mm{\times}20mm\;field,\;maximum\;6.6\%\;decrease\;in\;100mm{\times}50mm\;and\;maximum\;10.2\%\;decrease\;200mm{\times}100mm$, the larger decrease difference of PDD as the greater field size and as greater the depth, The difference of PDD between asymmetrical field and equivalent square field showed maximum $2.4\%\;decrease\;in\;60mm{\times}30mm\;field,\;maximum\;4.8\%\;decrease\;in\;150mm{\times}75mm\;and\;maximum\;6.1\%\;decrease\;in\;250mm{\times}125mm$, and the larger decreased differenced PDD as the greater field size and as greater the depth, these differences of PDD were out of $5\%$ of dose calculation as defined by international Commission on radiation unit and Measurements(ICRU). In the dose distribution of asymmetrical field (half beam) the plotted isodose curves were observed to have deviations by decreased PDD as greater as the blocking of the beam moved closer to the central axis, and as the asymmetrical field increased by moving the block 10 mm keeping away from the central axis, the PDD increased and plotted isodose curves were gradually more flattened, due to reduced amount of the primary beam and the fraction of low energy soft radiations by passing thougepth in asymmetrical field by moving independent jaw each 10 h beam flattening filter. As asymmetrical radiation field as half beam radiation technique is used, the radiation dosimetry calculated in utilizing the fundamental data which measured in standard symmetrical field should be converted on bases of nearly measured data in asymmetrical field, measured beam data flies of various asymmetrical field in various energy and be necessary in each institution.

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Monte Carlo Study Using GEANT4 of Cyberknife Stereotactic Radiosurgery System (GEANT4를 이용한 정위적 사이버나이프 선량분포의 계산과 측정에 관한 연구)

  • Lee, Chung-Il;Shin, Jae-Won;Shin, Hun-Joo;Jung, Jae-Yong;Kim, Yon-Lae;Min, Jeong-Hwan;Hong, Seung-Woo;Chung, Su-Mi;Jung, Won-Gyun;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.21 no.2
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    • pp.192-200
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    • 2010
  • Cyberknife with small field size is more difficult and complex for dosimetry compared with conventional radiotherapy due to electronic disequilibrium, steep dose gradients and spectrum change of photons and electrons. The purpose of this study demonstrate the usefulness of Geant4 as verification tool of measurement dose for delivering accurate dose by comparing measurement data using the diode detector with results by Geant4 simulation. The development of Monte Carlo Model for Cyberknife was done through the two-step process. In the first step, the treatment head was simulated and Bremsstrahlung spectrum was calculated. Secondly, percent depth dose (PDD) was calculated for six cones with different size, i.e., 5 mm, 10 mm, 20 mm, 30 mm, 50 mm and 60 mm in the model of water phantom. The relative output factor was calculated about 12 fields from 5 mm to 60 mm and then it compared with measurement data by the diode detector. The beam profiles and depth profiles were calculated about different six cones and about each depth of 1.5 cm, 10 cm and 20 cm, respectively. The results about PDD were shown the error the less than 2% which means acceptable in clinical setting. For comparison of relative output factors, the difference was less than 3% in the cones lager than 7.5 mm. However, there was the difference of 6.91% in the 5 mm cone. Although beam profiles were shown the difference less than 2% in the cones larger than 20 mm, there was the error less than 3.5% in the cones smaller than 20 mm. From results, we could demonstrate the usefulness of Geant4 as dose verification tool.

Dosimetric Characteristics of Detectors in Measurement of Beam Data for Small Fields of Linear Accelerator (선형가속기의 소조사면에 대한 빔 자료 측정에서 검출기의 선량 특성 분석)

  • Koo, Ki-Lae;Yang, Oh-Nam;Lim, Cheong-Hwan;Choi, Won-Sik;Shin, Seong-Soo;Ahn, Woo-Sang
    • Journal of radiological science and technology
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    • v.35 no.3
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    • pp.265-273
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    • 2012
  • Aquisition of accurate beam data is very important to calculate a reliable dose distribution of the treatment planning system for small radiation fields in intensity-modulated radiation therapy(IMRT) and stereotactic radiosurgery(SRS). For the measurement of small fields, the choice of a suitable detector is important due to the shape gradient in profile penumbra, the lack of lateral electronic equilibrium, and the effect of effective detector volume. Therefore, this study was to analyze the dosimetric characteristics of various detectors in measurement of beam data for small fields of linear accelerator. 0.01cc and 0.13cc ion chambers (CC01 and CC13) and a stereotactic diode detector(SFD) were used for measurement of small fields. The beam data, including the percent depth dose, output factor, and beam profile were acquired under 6 MV and 15 MV photon beams. Measurements were performed with the field size ranging from $2{\times}2cm^2$ to $5{\times}5cm^2$. For $2{\times}2cm^2$ field size, the differences of the ratios of $PDD_{20}$ and $PDD_{10}$ measured by CC01 and SFD detectors were 1.02% and 0.12% for 6 MV and 15 MV photon beams, respectively. For field sizes larger than $3{\times}3cm^2$, the differences of values of $PDD_{20}/PDD_{10}$ obtained from each detector were 1.15% and 0.71% for 6 MV and 15 MV photon beams, respectively. The output factors obtained from CC01 and SFD for $2{\times}2cm^2$ field size were within 0.5% and 1.5% for 6 MV and 15 MV, respectively. The differences in output factor of three detectors for $3{\times}3cm^2$ to $5{\times}5cm^2$ field sizes were within 0.5%. Profile penumbras measured by the SFD, CC01, and CC13 detectors at three depths were average 2.7 mm and 3.5 mm, 3.4 mm and 4.3 mm, and 5.2 mm and 6.1 mm for 6 MV and 15 MV photon beams, respectively. In conclusion, it could be possible to use of the CC01 and SFD detectors for the measurement of percent depth dose and output factor for $2{\times}2cm^2$ field size, and to use of three detectors for $3{\times}3cm^2$ to $5{\times}5cm^2$ field sizes. CC01 and SFD detectors, consider ably smaller than the radiation field, should be used in order to accurately measure the profile penumbra for small field sizes.

Treatment Effect of Green Manure Crops on Content of γ-Oryzanols from Korean Rice Variety, Unkwangbyeo (녹비 작물 처리에 따른 운광벼 중 감마오리자놀 변화)

  • Kim, Heon-Woong;Shin, Jae-Hyeong;Lee, Min-Ki;Lee, Sung-Hyeon;Jang, Hwan-Hee;Cho, Hyun-Suk;Lee, Jeong-Tae;Jeon, Weon-Tai;Kim, Jung-Bong
    • Korean Journal of Environmental Agriculture
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    • v.34 no.2
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    • pp.98-104
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    • 2015
  • BACKGROUND: ${\gamma}$-Oryzanol, a mixture of ferulic acid esters of triterpene alcohols and sterols, are a nutritionally important group of rice secondary metabolites. The ${\gamma}$-Oryzanol content and composition were found to vary with enviromental factors such as growth temperature, varietal origin, and cultivation method. Therefore, the effect of green manure treatments will be also be an important factor in their content. METHODS AND RESULTS: The ${\gamma}$-Oryzanols extracted using dichloromethane/methanol were analyzed equipped liquid chromatography with a diode array detector. A total of ten components of ${\gamma}$-oryzanol including ${\Delta}7$-stigmastenyl ferulate were isolated of which, cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, campesteryl ferulate and sitosteryl ferulate were identified as the major components in Korean rice variety, Unkwang. The ${\gamma}$-oryzanol content in rice, in the presence of nitrogen fertilization using green manure was similar to conventional nitrogen fertilization, but was higher than the control(no fertilizations). The ${\gamma}$-oryzanol ontent in rice, in the presence of hairy vetch as green manure crop was the highest compared to other crops (opium-poppy, crimson clover, cornflower). As a result of PLS-DA using SIMCA 11.0 ver. as multivariate analysis program on the basis of total data, in all samples, the specific pattern and cluster of ${\gamma}$-oryzanol scores according to green manure crops and conditions were confirmed with possible distinguishing nitrogen effects. CONCLUSION: The nitrogen contained in the green manure crops is considered to play a major role in the formation of ${\gamma}$-oryzanol. Hairy vetch which contains higher nitrogen increased the concentration of ${\gamma}$-oryzanol in rice.

Development of Passive Millimeter-wave Security Screening System (수동 밀리미터파 보안 검색 시스템 개발)

  • Yoon, Jin-Seob;Jung, Kyung Kwon;Chae, Yeon-Sik
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.7
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    • pp.138-143
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    • 2016
  • The designed and fabricated millimeter-wave security screening system receives radiation energy from an object and a human body. The imaging system consist of sixteen array antennas, sixteen four-stage LNAs, sixteen detectors, an infrared camera, a CCD camera, reflector, and a focusing lens. This system requires high sensitivity and wide bandwidth to detect the input thermal noise. The LNA module of the system has been measured to have 65.8 dB in average linear gain and 82 GHz~102 GHz in bandwidth to enhance the sensitivity for thermal noise, and to receive it over a wide bandwidth. The detector is used for direct current (DC) output translation of millimeter-wave signals with a zero bias Schottky diode. The lens and front-end of the millimeter-wave sensor are important in the system to detect the input thermal noise signal. The frequency range in the receiving sensitivity of the detectors was 350 to 400 mV/mW at 0 dBm (1 mW) input power. The developed W-band imaging system is effective for detecting and identifying concealed objects such as metal or plastic.