• Bulletin of the Korean Chemical Society
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• 제24권8호
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• pp.1163-1168
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• 2003

The structures of molecular species of galactolipids, such as monogalactosyl diacylglycerol (MGDG) and digalactosyl diacylglycerol (DGDG), isolated from wheat flour have been investigated using negative-ion electrospray ionization (ESI) mass spectrometry interfaced with high performance liquid chromatography (HPLC). According to the result of HPLC analysis, MGDG and DGDG were found to consist of mixtures of five and four molecular species, respectively. The galactolipids have been also analyzed to determine their fatty acid compositions, using HPLC/ESI-MS combined with in-source (or cone voltage) fragmentation. HPLC/ ESI-MS is very useful for one-step analysis of mixtures of galactolipids with a small sample quantity. Especially, the carboxylate anions produced in in-source fragmentations of the negative-ion of each component separated by HPLC provide valuable information on the composition of its fatty acyl chains.

• Environmental Engineering Research
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• 제23권4호
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• pp.390-396
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• 2018

This study investigated the transformation of dissolved organic matter (DOM) in a free-water surface flow constructed wetland. Pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) coupled with preparative high-performance liquid chromatography (prep-HPLC) was used to analyze the compositions of biopolymers (polysaccharides, amino sugars, proteins, polyhydroxy aromatics, lipids and lignin) in DOM according to the molecular size at three sampling points of the water flow: inflow, midflow, and outflow. The prep-HPLC results verified the decomposition of DOM through the decrease in the number of peaks from three to one in the chromatograms of the sampling points. The Py-GC/MS results for the degradable peaks indicated that biopolymers relating to polysaccharides and proteins gradually biodegraded with the water flow. On the other hand, the recalcitrant organic fraction (the remaining peak) in the outflow showed a relatively high concentration of aromatic compounds. Therefore, the ecological processes in the constructed wetland caused DOM to become more aromatic and homogeneous. This indicated that the constructed wetland can be an effective buffer area for releasing biochemically stable DOM, which has less influence on biological water quality indicators, e.g., biochemical oxygen demand, into an aquatic ecosystem.

• Mass Spectrometry Letters
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• 제2권1호
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• pp.16-19
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• 2011

Oxidation products of ceftiofur were formed in hydrogen peroxide solution. The structures of the ceftiofur oxidation products were characterized by high-performance liquid chromatography/electrospray ionization/tandem mass spectrometry (HPLC/ESI/MS/MS). The products were identified as compounds oxidized at the sulfur of a cephem ring. For further analysis, experiments were performed using $O^{18}$-labeled hydrogen peroxide. In addition, density-functional calculations were carried out for six possible oxidation products to support the experimental results.

• Journal of Applied Biological Chemistry
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• 제66권
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• pp.338-344
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• 2023

Curcuma longa is a plant belonging to the genus Curcuma and is distributed across various Asian regions. This plant is widely known for its rhizomes, which possess a variety of pharmacological properties. However, although the leaves and stems of this plant also contain several health-promoting secondary metabolites, very few studies have characterized these compounds. Therefore, our study sought to quantify the secondary metabolites from the leaves and stems of Curcuma longa L. (LSCL) using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and high-performance liquid chromatography (HPLC). Our LC-ESI-MS analyses detected twenty-one phenolic compounds in the LSCL, among which fifteen compounds were detected via HPLC analysis. Four compounds, namely vanillic acid (0.129 mg/g), p-coumaric acid (0.431 mg/g), 4-methylcatechol (0.199 mg/g), and afzelin (0.074 mg/g) were then quantified. These findings suggest that LSCL is rich in secondary metabolites and holds potential as a valuable resource for the development of functional and nutritional supplements in the future.

• Mass Spectrometry Letters
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• 제5권1호
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• pp.24-29
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• 2014

An advanced and reliable high performance liquid chromatography (HPLC)/ultraviolet detector (UV)/ion-trap time-of-flight (IT-TOF) mass spectrometry was developed for the simultaneous quantification of 19 marker compounds in Bang-poong-tong-sung-san (BPTS), a traditional oriental prescription. Various parameters affecting HPLC separation and IT-TOF detection were investigated, and optimized conditions were identified. The separation was achieved on a Capcell PAK C18 column ($1.5mm{\times}250mm$, $5{\mu}m$ particle size) using a gradient elution of acetonitrile and water containing 0.1% formic acid at a flow rate of 0.1 mL/min. The column temperature was maintained at $40^{\circ}C$ and the injection volume was $2{\mu}L$. IT-TOF system was equipped with an electrospray ion source (ESI) operating in positive or negative ion mode. The optimized electrospray ionization parameters were as follows: ion spray voltage, +4.5 kV (positive ion mode), or -3.5 kV (negative ion mode); drying gas ($N_2$), 1.5 L/min; heat block temperature, $200^{\circ}C$. Automatic $MS^n$ (n = 1~3) analyses were carried out to obtain structural information of analytes. Elemental compositions and their mass errors were calculated based on their accurate masses obtained from a formula predictor software. The marker compounds in BPTS were identified by comparisons between $MS^n$ spectra from standards and those from extracts. Moreover, the libraries of $MS^2$ and $MS^3$ spectra and accurate masses of parent and fragment ions for marker compounds were constructed. The developed method was successfully applied to the BPTS extracts and identified 17 out of 19 marker compounds in the BPTS extracts.

• 한국식품영양과학회지
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• 제29권5호
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• pp.747-751
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• 2000

본 연구에서는 생각의 매운맛을 주요성분인 gingerol 화합물의 분석방법을 개선할 목적으로, 원료 생각을 아세톤으로 추출한 후 그 추출물을 TLC 및 LiChrosorb RP-18 column으로 장착된 HPLC를 사용하여 3가지 gingerol 동족체 화합물을 분리하였고, LC/MS 및 NMR로 확인한 결과 생강의 동족체 화합물은 [6]-, [8]-, [10]-gingerol로 확인되었다. 본 방법으로 추출한 gingerol 표준품을 사용하여 시판 원료생강 및 생각 페이스트 중의 gingerol 함량을 측정한 결과, 전자의 경우 [6]-, [8]-, [10]-gingerol 함량은 635.5 mg%, 206.6 mg%, 145.7 mg%이었고, 후자의 경우는 418.2 mg%, 142.6 mg%, 103.3 mg%로 각각 구성되어 있었다.

• 한국동물위생학회지
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• 제27권1호
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• pp.17-29
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• 2004

A multiresidual analysis was performed to determine 12 sulfonamides(sulfacetamide, sulfadiazine, sulfisomidine, sulfathiazole, sulfapyridine, sulfamerazine, sulfamethazine, sulfamonomethoxine, sulfisoxazole, sulfamethoxazole, sulfaquinoxaline, and sulfadimethoxine) in beef and pork simultaneously. The multiresidual analysis for the sulfonamides currently used was able to analyze 5 kinds of sulfonamides at the same time. The method of this 12 sulfonamides multiresidual analysis in this study was matrix solid-phase dispersion(MSPD) by high performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC/MS). The recovery rate of the materials was measured by MSPD method with 3 different extraction solvents; Dichloromethane, DCM: Ethylacetate(3:1), DCM:EA(9:1). Also, samples (84 beef and 205 pork samples) which were positive by EEC-4 plate test from 2001 to 2003 were tested to investigate the kinds of sulfonamides using HPLC. The results from the study were as follows; 1. The recovery rate of the materials was measured by MSPD method with 3 different extraction solvents; Dichloromethane, DCM:Ethylacetate(3:1), DCM:EA(9:1). The method of extraction solvent with DCM:ethyl acetate(9:1) was the most excellent(87.7∼99.3%) in separation and reappearance. 2. In the LC/MS analysis. of sulfonamides, signal to noise ratio was showed relatively high in the positive mode and special ion in the quality analysis was determined via [M+H]$\^$+/ and m/z 156. A spectrum of sulfonamides was showed from all 12 sulfonamides. 3. The samples positive by the EEC-4 plate, a screening test method, were categorized by sulfonamides through Charm II and confirmed the kinds of sulfonamides through HPLC. 1) Among 84 beef samples positive by EEC-4 plate, 20 samples were positive by Charm II and identified as 7 sulfamethazine, 9 sulfadimethoxine, 1 sulfamonomethoxine and 3 unknown status. 2) Among 205 pork samples positive by EEC-4 plate, 42 samples were positive by Charm II and identified as 19 sulfamethazine, 1 sulfadimethoxine, 4 sulfamonomethoxine and 5 unknown status.

• 분석과학
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• 제19권6호
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• pp.519-528
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• 2006

본 연구에서는 뇨시료를 고체상 추출법으로 추출한 후 HPLC/DAD/ESI-MS(high-performance liquid chromatograph/diode array detector/electro-spray ionitation mass spectrometry)를 사용하여 분석하였다. 7종의 thyroid hormones의 HPLC 분리조건은 Hypersil ODS(octadecylsilica) 컬럼(4.6mm I.D., 100 mm length, particle size $5{\mu}m$)을 사용하고 ammonium formate buffer와 acetonitrile을 이동상으로 하여 기울기 용리한 결과 완전 분리가 가능하였으며, UV spectra 및 질량스펙트럼을 확인할 수 있었다. 고체상 추출법에 의한 전처리 최적 조건을 조사한 결과 시료를 pH 3으로 한 후 C18 고체상을 사용하여 4 mL의 methanol/ammonium hydroxide(9:1) 혼합용액으로 용리할 경우 회수율이 89.0-113.1%로 나타났다. HPLC/DAD를 이용하여 10-1000 ng/mL범위에서 검량선을 작성한 결과 $r^2$값은 0.992-0.998 으로 나타났으며 검출한계는 2-4 ng/mL(3.8-13.0 pmol/mL)로 계산되었다.

• 분석과학
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• 제21권4호
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• pp.245-258
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• 2008

본 연구에서는 하고초의 지표성분인 triterpenic acids 5종을 컬럼 크로마토그래피와 역상 HPLC를 이용하여 추출 및 분리했고, 이들 성분의 순도는 90% 이상임을 HPLC를 이용하여 확인했다. 고속원자충돌 이온화법-고분해능 질량분석기(FAB-HRMS)를 사용하여 지표성분의 분자량 및 원소조성을 결정했으며, 지표성분의 구조 분석은 FAB-MS/MS 의해 음이온 및 양이온 모드에서 수행하였다. Triterpenic acid류의 충돌유발분해(collision-induced dissociation, CID) 탄뎀질량분석(MS/MS) 스펙트럼에서 protonated molecule인 $[M+H]^+$ 및 deprotonated molecule인 $[M-H]^-$ 이온의 CID는 주로 retro Diels-Alder (RDA), 탈수 (dehydration) 및 탈탄산(decarboxylation) 반응에 의한 다양한 생성이온들이 나타났다. 특히, $[M-H]^-$이온의 CID-MS/MS 스펙트럼에서는 charge-remote fragmentation (CRF) 현상에 의한 이온들도 특성이온으로 나타났다. 이들 CID-MS/MS 스펙트럼의 해석을 통하여 하고초의 지표성분인 triterpenic acids의 구조 규명을 수행하였다.

• 산업식품공학
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• 제22권4호
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• pp.295-303
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• 2018

Polyphenol profiles, physicochemical properties, antioxidant activities, and inhibitory effect of adipocyte differentiation of Houttuynia cordata fermented with Lactobacillus brevis B84 were evaluated. Six polyphenols were characterized for this plant by using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and the results were compared with total phenolic content by a spectrophotometric method. The total amount of the identified polyphenols was lower than that determined by the spectrophotometric method. However, the fermentation process influenced polyphenol composition such as content of vanillic acid and caffeic acid. The phytochemical profiles were evaluated by high-performance liquid chromatography with UV and electrospray ionization mass spectrometry detection ($HPLC-DAD-ESI-MS^n$). Total sugar and reducing sugar contents decreased after fermentation. Antioxidant activities such as DPPH, ABTS, and superoxide anion radical scavenging and reducing power were evaluated to compare the beneficial effect after fermentation. Fermented H. cordata increased the lipolytic effect in 3T3-L1 adipocytes. Overall, the results indicate that the fermentation of H. cordata with L. brevis B84 produces changes of phenolic compounds, antioxidant activity, and lipolytic effect.