• Mass Spectrometry Letters
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• 제6권4호
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• pp.99-104
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• 2015

A liquid chromatography mass spectrometry (LC-MS) system was used to identify and distinguish oligostilbene diastereoisomers. A polyphenolic extract from Neobalanocarpus heimii known to be rich in oligostilbenes of various degrees of condensation was used as test material. Fourteen oligostilbenes were isolated from this extract on a fully automated semi-preparative HPLC system. Out of these, two pairs of dimers, one pair of trimers, two pairs of tetramers and a group of four tetramers with similar skeleton were identified as diastereoisomers. Their structures and configurations were established by spectroscopic methods. All isolated compounds were subjected to an LC-MS/MS to study their fragmentation patterns. The experiments were performed on a liquid chromatography-mass spectrometry (LC-MS) with electrospray-ionization (ESI) interface in positive mode. MS/MS spectra of each pure compound were recorded by direct infusion in identical conditions and their product ion spectra were analysed. Some subtle yet significant differences were observed between the spectra of oligostilbenes from the various diastereoisomeric series.

• 분석과학
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• 제15권2호
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• pp.120-126
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• 2002

유도결합 플라스마 질량분석기(ICP-MS)와 유도결합 플라스마 원자방출분광기 (ICP-AES)를 이용하여 상업적으로 유통되고 있는 4 종의 분무기(Meinhard, ESI PFA, Cross-flow, Babington)와 한국표준과학연구원(KRISS)에서 직접 제작한 분무기인 KRISS Inert 분무기와 KRISS conespray 분무기의 성능을 평가하였다. 각 분무기의 압력, 시료주입량의 변화에 따른 시료주입 효율을 조사하였으며 ICP-MS와 ICP-AES에 연결하였을 때 시료주입량의 변화에 따른 감도, 안정성, 바탕선 세기, 산화물과 수소화물의 생성 비율을 조사하였다. 시료의 종류, 시료 양의 제한성, 분석기기의 종류, 분석 원소에 따라 가장 적합한 분무기를 선택해야 높은 감도, 낮은 바탕값, 안정한 신호세기 등의 좋은 분석결과를 얻을 수 있음을 알 수 있었다.

• Animal Bioscience
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• 제36권9호
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• pp.1367-1375
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• 2023

Objective: Pigment production and distribution are controlled through multiple proteins, resulting in different coat color phenotypes of sheep. Methods: The expression distribution of vimentin (VIM) and transthyretin (TTR) in white and black sheep skins was detected by liquid chromatography-electrospray ionization tandem MS (LC-ESI-MS/MS), gene ontology (GO) statistics, immunohistochemistry, Western blot, and quantitative real time polymerase chain reaction (qRT-PCR) to evaluate their role in the coat color formation of sheep. Results: LC-ESI-MS/MS results showed VIM and TTR proteins in white and black skin tissues of sheep. Meanwhile, GO functional annotation analysis suggested that VIM and TTR proteins were mainly concentrated in cellular components and biological process, respectively. Further research confirmed that VIM and TTR proteins were expressed at significantly higher levels in black sheep skins than in white sheep skins by Western blot, respectively. Immunohistochemistry notably detected VIM and TTR in hair follicle, dermal papilla, and outer root sheath of white and black sheep skins. qRT-PCR results also revealed that the expression of VIM and TTR mRNAs was higher in black sheep skins than in white sheep skins. Conclusion: The expression of VIM and TTR were higher in black sheep skins than in white sheep skins and the transcription and translation were unanimous in this study. VIM and TTR proteins were expressed in hair follicles of white and black sheep skins. These results suggested that VIM and TTR were involved in the coat color formation of sheep.

• 분석과학
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• 제20권2호
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• pp.115-123
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• 2007

헤테로싸이클릭 아민류(heterocyclic amines, HAs)는 소고기, 돼지고기, 닭고기 그리고 생선과 같은 근육질의 육류를 조리 할 때 생겨나는 돌연변이원성/발암성 화학물질로 잘 알려져 있다. 식품으로부터 HAs의 분석에 있어 가장 큰 어려움은 HAs가 식품 중에 극히 미량(수 ng/g)으로 존재한다는 것과 많은 방해물질이 존재한다는 것이다. 식품으로부터 HAs를 추출하고 정제하기 위해 고체-상 추출(solid-phase extraction, SPE)이 많이 사용되고 있다. HAs 분석을 위해 여러 단계의 SPE 과정을 수행하였다. HAs의 회수율은 표준물질이 녹여져 있는 메탄올 수용액과 조리되지 않은 돼지고기에 표준용액을 스파이크하여 서로를 비교하여 얻었다. 회수율은 25.0 ng/g에서 25.3~93.0%의 값을 얻을 수 있었다. 확립된 감도 좋고 재현성있는 시료전처리방법을 통해서 ${\mu}$-LC/ESI-MS에 주입함으로써 조리된 육류로부터 HAs를 분석하는데 응용될 수 있을 것이다. 다른 방법으로는 freezing filtration 방법으로써 보다 좋은 추출 효율과 재현성을 나타내었다.

• 생약학회지
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• 제44권4호
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• pp.350-361
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• 2013

Asarum sieboldii has been used for treatment of fever, pain, common cold, and chronic sinusitis in Korea. In this study, we performed quantification analysis of seven major constituents including aristolochic acid I, aristolochic acid II, ${\alpha}$-asarone, ${\beta}$-asarone, elemicin, methyl eugenol, and safrole in the 70% ethanol extract of Asarum sieboldii and its solvent fractions, n-hexane, ethylacetate, n-butanol, and water ones using a ultra-performance liquid chromatography-electrospray ionization-mass spectrometer(UPLC-ESI-MS) and gas chromatography-mass spectrometer(GC-MS). Regression equations of seven components were acquired with $r^2$ values >0.99. The values of limit of detection(LOD) and quantification(LOQ) were 0.1-3.9 ng/mL and 0.3-11.7 mg/mL, respectively. The amount of the seven compounds in Asarum sieboldii were not detected -143.66 mg/g. The established LC-MS/MS and GC-MS methods will be helpful to improve quality control of Asarum sieboldii.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.724-724
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• 2003

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4415-4418
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• 2011

• Bulletin of the Korean Chemical Society
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• 제29권12호
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• pp.2465-2470
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• 2008

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3517-3518
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• 2010

• 한국작물학회:학술대회논문집
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• 한국작물학회 2019년도 추계학술대회
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• pp.208-208
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• 2019