• 제목/요약/키워드: electrospray

검색결과 440건 처리시간 0.024초

추황배(Pyrus pyrifolia Nakai cv. Chuhwangbae) 과피로부터 2종의 Flavonoids의 단리·동정 (Isolation and Identification of Two Flavonoids from Pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) Fruit Peel)

  • 이상원;이유건;조정용;김영출;이상현;김월수;문제학
    • 한국식품과학회지
    • /
    • 제47권2호
    • /
    • pp.170-175
    • /
    • 2015
  • 본 연구에서는 국산배의 기능학적 우수성 증명을 위해 국산배로부터 생리활성 화합물을 밝히고자 하였다. 이에 배 과피 MeOH 추출물을 용매분획하여 얻은 EtOAc-산성획분을 대상으로 Sephadex LH-20 column chromatography와 ODS-HPLC를 이용하여 순차적으로 정제를 행하여 2종의 화합물을 단리하였다. 단리된 화합물 1과 2는 MS 및 NMR 분석을 통하여 각각 quercetin 3-O-${\beta}$-Dglucopyranoside(화합물 1)와 3,5,6,7,8,3',4'-heptahydroxyflavan [(-)-dulcisflavan, 화합물 2)]으로 동정되었다. 단리된 화합물 1은 동양배로부터, 그리고 화합물 2는 배로부터 처음 동정된 화합물이다. 본 연구결과가 국산배의 기능학적 우수성 증명을 위한 기초자료로 활용되길 기대한다.

다양한 데침조건에서 돌산갓의 이화학적 특성 및 LC-PDA/MS/MS 분석 (Quality Characteristics of Dolsan Leaf Mustard according to Various Blanching Conditions and Liquid Chromatography with Photodiode Array and Tandem Mass Spectrometry Analysis)

  • 손혜련;오선경;;최명락
    • KSBB Journal
    • /
    • 제31권1호
    • /
    • pp.20-26
    • /
    • 2016
  • This study aims to examine the optimum blanching conditions as a pretreatment condition to improve the storage stability of Dolsan leaf mustard pickle. The effects of the blan- ching temperature and time were investigated at a temperature range of $80-100^{\circ}C$. Sampling was done for 1 month after a 5 days interval. The L value of the Dolsan leaf mustard was found to be the highest at $80^{\circ}C$. The cutting force increased as the blanching temperature increased. The tensile strength decreased at $95^{\circ}C$ and $100^{\circ}C$. In addition, the sensory evaluation scores were the best at $80^{\circ}C$. The storage stability was assessed at various blanching temperatures to increase the sinigrin content during storage. Liquid chromatography with photodiode array and tandem mass spectrometry (LC-PDA/MS/MS) analysis was conducted to identify and quantify the sinigrin content in the Dolsan leaf mustard. Sinigrin as an internal standard was co-injected into each sample solution. The sample was monitored by recording the ultraviolet absorbance at 228 nm and by electrospray ionization (ESI) positive ion mode in the m/z 50-1,500 range. Blanching the sample at $80^{\circ}C$ showed the highest sinigrin concentration during storage among various temperatures and the maximum concentration was 350 ppm at 15 days storage. Study on utilization of vegetable from food processing of leaf mustard and preservation conservation results suggest that blanching at $80^{\circ}C$ is expected to improve the palatability of the pickle.

LC-ESI-MS/MS를 이용한 생체시료 중 브롬화피나베리움의 고감도 분석 및 이를 이용한 생체이용률 평가 (Sensitive Determination of Pinaverium Bromide in Human Plasma by LC-ESI-MS/MS : Applicability to Oral Bioavailability Determination)

  • 박석;이예리;김호현;이희주;김윤균;염정록;한상범
    • Journal of Pharmaceutical Investigation
    • /
    • 제34권6호
    • /
    • pp.513-519
    • /
    • 2004
  • A sensitive method for quantification of pinaverium bromide in human plasma was established using liquid chromatography-electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS). Glimepiride was used as internal standard. Pinaverium bromide and internal standard in plasma sample were extracted using tert-butylmethylether(TBME). A centrifuged upper layer was then evaporated and reconstituted with mobile phase of acetonitrile-5 mM ammonium formate (80/20, pH 3.0). The reconstituted samples were injected into a $C_{18}$ reversed-phase column. Using MS/MS with multiple reaction monitoring (MRM) mode, pinaverium and glimepirde were detected without severe interference from human plasma matrix. Pinaverium produced a protonated precursor ion $([M+H]^+)$ at m/z 510.3 and a corresponding product ion at m/z 228.9. Internal standard produced a protonated precursor ion $([M+H]^+)$ at m/z 491.5 and a corresponding product ion at m/z 352.0. Detection of pinaverium bromide in human plasma was accurate and precise, with limit of quantitation at 0.5 ng/ml. The method has been successfully applied to bioavailability study of pinaverium bromide tablet in Korean healthy male volunteers. Pharmacokinetic parameters such as $AUC_t,\;C_{max},\;T_{max},\;K_{el}\;and\;t_{1/2}$ were calculated.

Comparative Proteomic Analyses of the Yeast Saccharomyces cerevisiae KNU5377 Strain Against Menadione-Induced Oxidative Stress

  • Kim, Il-Sup;Yun, Hae-Sun;Jin, In-Gnyol
    • Journal of Microbiology and Biotechnology
    • /
    • 제17권2호
    • /
    • pp.207-217
    • /
    • 2007
  • The Saccharomyces0 cerevisiae KNU5377 strain, which was isolated from spoilage in nature, has the ability to convert biomass to alcohol at high temperatures and it can resist against various stresses [18, 19]. In order to understand the defense mechanisms of the KNU5377 strain under menadione (MD) as oxidative stress, we used several techniques for study: peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) followed by two-dimensional (2D) gel electrophoresis, liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), and surface-enhanced laser desorption ionization-time of flight (SELDI-TOF) technology. Among the 35 proteins identified by MALDI-TOF MS, 19 proteins including Sod1p, Sod2p, Tsa1p, and Ahp1p were induced under stress condition, while 16 proteins were augmented under normal condition. In particular, five proteins, Sod1p, Sod2p, Ahp1p, Rib3p, Yaf9p, and Mnt1p, were induced in only stressed cells. By LC-ESI-MS/MS analysis, 37 proteins were identified in normal cells and 49 proteins were confirmed in the stressed cells. Among the identified proteins, 32 proteins were found in both cells. Five proteins including Yel047cp and Met6p were only upregulated in the normal cells, whereas 17 proteins including Abp1P and Sam1p were elevated in the stressed cells. It was interesting that highly hypothetical proteins such as Ynl281wp, Ygr279cp, Ypl273wp, Ykl133cp, and Ykr074wp were only expressed in the stressed cells. SELDI-TOF analysis using the SAX2 and WCX2 chips showed that highly multiple-specific protein patterns were reproducibly detected in ranges from 2.9 to 27.0 kDa both under normal and stress conditions. Therefore, induction of antioxidant proteins, hypothetical proteins, and low molecular weight proteins were revealed by different proteomic techniques. These results suggest that comparative analyses using proteomics might contribute to elucidate the defense mechanisms of KNU5377 under MD stress.

Synthesis of Curcumin Glycosides with Enhanced Anticancer Properties Using One-Pot Multienzyme Glycosylation Technique

  • Gurung, Rit Bahadur;Gong, So Youn;Dhakal, Dipesh;Le, Tuoi Thi;Jung, Na Rae;Jung, Hye Jin;Oh, Tae Jin;Sohng, Jae Kyung
    • Journal of Microbiology and Biotechnology
    • /
    • 제27권9호
    • /
    • pp.1639-1648
    • /
    • 2017
  • Curcumin is a natural polyphenolic compound, widely acclaimed for its antioxidant, anti-inflammatory, antibacterial, and anticancerous properties. However, its use has been limited due to its low-aqueous solubility and poor bioavailability, rapid clearance, and low cellular uptake. In order to assess the effect of glycosylation on the pharmacological properties of curcumin, one-pot multienzyme (OPME) chemoenzymatic glycosylation reactions with UDP-${\alpha}-{\text\tiny{D}}$-glucose or UDP-${\alpha}-{\text\tiny{D}}$-2-deoxyglucose as donor substrate were employed. The result indicated significant conversion of curcumin to its glycosylated derivatives: curcumin 4'-O-${\beta}$-glucoside, curcumin 4',4"-di-O-${\beta}$-glucoside, curcumin 4'-O-${\beta}$-2-deoxyglucoside, and curcumin 4',4"-di-O-${\beta}$-2-deoxyglucoside. The products were characterized by ultra-fast performance liquid chromatography, high-resolution quadruple-time-of-flight electrospray ionization-mass spectrometry, and NMR analyses. All the products showed improved water solubility and comparable antibacterial activities. Additionally, the curcumin 4'-O-${\beta}$-glucoside and curcumin 4'-O-${\beta}$-2-deoxyglucoside showed enhanced anticancer activities compared with the parent aglycone and diglycoside derivatives. This result indicates that glycosylation can be an effective approach for enhancing the pharmaceutical properties of different natural products, such as curcumin.

On-Line SPE-LC/MSD 시스템을 이용한 수중의 과불화 화합물(PFCs) 분석 (Application of On-Line SPE-LC/MSD to Measure Perfluorinated Compounds (PFCs) in Water)

  • 손희종;염훈식;정종문;장성호
    • 대한환경공학회지
    • /
    • 제35권2호
    • /
    • pp.75-83
    • /
    • 2013
  • 본 연구는 기존의 고상추출(SPE) 과정을 분석장비인 LC/MSD에 on-line으로 연결함으로써 cartridge의 건조를 막아 target 물질의 손실을 최대한 억제하였으며 11종의 PFCs에 대해 실제 matrix가 있는 낙동강 원수를 이용한 실험에서 $80.4{\pm}5.2%{\sim}109.5{\pm}1.4%$ 범위의 높은 회수율을 구할 수 있었다. 낙동강에서의 PFCs 분포를 조사한 결과 하수처리장 방류수의 영향을 받는 지역(진천천과 금호강 하류)은 고농도의 PFCs가 검출되었으며, 낙동강 하류의 매리원수에서는 검출농도가 급격히 감소하여 PFOA만 8.0 ng/L의 농도로 검출되었다. 외국의 PFCs 검출현황을 보고한 연구결과들과 비교해 볼 때 낙동강 지류에서는 비교적 높은 농도로 PFCs가 검출되어 안심할 수 있는 수준은 아니었으며, 낙동강 본류의 경우도 여러 지역의 상수원으로 이용되기 때문에 주기적인 모니터링이 필요한 것으로 나타났다.

Analysis of erectile dysfunction drugs and their analogues in counterfeit drugs and herbal medicines by LC-ESI-MS/MS

  • Lee, Ji Hyun;Jeong, Ji Hye;Park, Hyoung-Joon;Do, Jung Ah;Heo, Seok;Cho, Sooyeul;Yoon, Chang-Yong
    • 분석과학
    • /
    • 제29권4호
    • /
    • pp.155-161
    • /
    • 2016
  • Distribution of various illegal or counterfeit drugs of seven approved erectile dysfunction drugs and their analogues has been increased, causing health problems such as cardiovascular disorder, tachycardia, headache, or vision disturbance. We used liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) to determine the erectile dysfunction drugs and their analogues in various counterfeit drugs. Eleven erectile dysfunction drugs and their analogues were detected, with sildenafil and its analogues being the most counterfeited compounds (73.8 %), followed by tadalafil and its analogues (25.4 %). The limits of detection (LOD) and the limits of quantitation (LOQ) of liquid-type and solid-type negative samples ranged from 0.1 to 3.3 ng/mL or ng/g and from 0.3 to 10.0 ng/mL or ng/g, respectively. The recoveries ranged from 84.3 to 112.3 % and 83.2 to 110.2 %, respectively. The contents of sildenafil and tadalafil in the various counterfeit drugs ranged from 21.0 to 947.5 mg/g and from 0.2 to 170.2 mg/g, respectively.

초소수성 전기 분무 마이크로 추진 장치 및 마이크로 추력 측정 (Study on super-hydrophobic electro-spray micro thruster and measurement of micro scale thrust)

  • 이영종;유용훈;;김상훈;박배호;변도영
    • 한국항공우주학회지
    • /
    • 제37권2호
    • /
    • pp.175-180
    • /
    • 2009
  • 이 논문은 폴리머 기반의 전기 분무 장치를 만들기 위하여 이온빔 장치를 통하여 초소수성으로 가공 된 polytetrafluoroethylene(PTFE) 노즐을 사용하였다. 초소수성 표면을 만들기 위하여, PTFE 표면은 Ar과 $O_2$를 이용한 이온빔 공정 장치를 사용하였다. 최적의 표면 공정 조건은 Ar과 $O_2$ 유량 및 에너지 단위를 변화 시켜 얻을 수 있었다. 공정된 노즐의 표면 특성을 분석하기 위하여 접촉각 측정을 수행하였고, 표면의 형태적 분석을 위해 scanning electron microscope(SEM) 그리고 atomic force microscope(AFM) 측정을 하였다. 초소수성으로 공정된 노즐을 사용함으로써 보다 안정적이고 반복적인 전기 분무가 가능함을 확인 하였으며, 공정 된 노즐의 성능을 평가하기 위하여 외팔보와 이온빔으로 표면 처리 된 노즐 그리고 레이져 변위센서를 이용하여 마이크로 스케일의 추력을 측정하였다.

LC-MS/MS를 이용한 계지복령환(桂枝茯苓丸)의 동시분석 및 항산화 효능 연구 (Quantitative Analysis and Antioxidant Effects of Gyejibokryeong-hwan)

  • 서창섭;김온순;신현규
    • 생약학회지
    • /
    • 제45권3호
    • /
    • pp.240-248
    • /
    • 2014
  • Gyejibokryeong-hwan (GJBRH) has been used for treatment of patients with climacteric syndrome. In this study, an ultra-performance liquid chromatography-electrospray ionization-mass spectrometer (UPLC-ESI-MS) method was established for the simultaneous quantification of seven marker compounds in GJBRH extract. In addition, we assessed the antioxidant effects of GJBRH. All analytes were separated by gradient elution using two mobile phases on a UPLC BEH $C_{18}$ column and maintained at $45^{\circ}C$. The antioxidant activities of GJBRH were evaluated by measuring free radical scavenging activities on 2,2'-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) and 1-1-diphenyl-2-picrylhydrazyl (DPPH). The inhibitory effects on low-density lipoprotein (LDL) oxidation were evaluated by the formation of thiobarbituric acid relative substances (TBARS) and relative electrophoretic mobility (REM). Regression equations of the seven compounds were acquired with $r^2$ values ${\geq}0.9988$. The amounts of the seven compounds, amygdalin, albiflorin, paeoniflorin, coumarin, cinnamic acid, cinnamaldehyde, and paeonol in GJBRH water extract were 21.71, 2.16, 17.17, 1.97, 0.40, 0.78, and 3.42 mg/g, respectively. The GJBRH showed the radical scavenging activity in a dose-dependent manner. The concentration required for 50% reduction ($RC_{50}$) against ABTS and DPPH radicals were $54.18{\mu}g/mL$ and $79.53{\mu}g/mL$. Furthermore, GJBRH reduced the oxidation properties of LDL induced by $CuSO_4$.

Simultaneous Analysis of Bioactive Metabolites from Rehmannia glutinosa by HPLC-DAD-MS/MS

  • Won, Tae-Hyung;Ryu, Sung-Kwang;Kang, Sam-Sik;Shin, Jong-Heon
    • Natural Product Sciences
    • /
    • 제16권2호
    • /
    • pp.116-122
    • /
    • 2010
  • A high-performance liquid chromatography (HPLC) with diode array detector (DAD) and electrospray ionization mass spectrometry (ESI-MS) was established for the simultaneous determination of five representative metabolites of the iridoid and phenolic classes from Rehmannia glutinosa. The optimal chromatographic conditions were obtained on an ODS column (5 mm, $4.6{\times}250\;mm$) with the column temperature at $25^{\circ}C$. The mobile phase was composed of water and acetonitrile using a gradient elution with the flow rate 0.3 mL/min. Detection wavelength was set at 205 nm. All calibration curves showed good linear regression ($r^2$ > 0.997) within test ranges. Limits of detection (LOD) and quantitation (LOQ) values were lower than 0.123 and $0.373\;{\mu}g/mL$, respectively. The developed method provided satisfactory precision and accuracy with overall intra-day and inter-day variations of 0.09 - 0.76% and 0.16 - 1.41%, respectively, and the overall recoveries of 99.03 - 102.67% for all of the compounds analyzed. In addition, effectiveness of diverse extraction methods was compared to each other for the development of standard analytic method. The verified method was successfully applied to the quantitative determination of five representative metabolites in twenty-one commercial Rehmannia glutinosa samples from different markets in Korea and China. The analytical results showed that the contents of the five analytes vary significantly with sources.