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Isolation and Structure Determination of Bioactive Compounds from the halophyte Artemisia scoparia
Get PDF염생습지에 자생하는 염생식물은 육상식물과 달리 계절과 조석의 영향으로 토양의 염분도가 극단적으로 바뀌는 환경에 자생하고 있다. 따라서 이러한 특이한 환경에 서식하는 염생식물은 육상식물과는 다른 이차대사산물을 생성시킬 가능성이 높다고 여겨진다. 또한 염생습지의 높은 염분성분은 산화환경을 야기시켜 활성산소종을 빈번히 발생시키기 때문에 염생식물들은 이러한 활성산소종을 제거하기 위한 강력한 항산화기작을 가지고 있는 것으로 알려져 있어 흥미있는 항산화물질의 존재가능성도 매우 높다고 할 수 있다.
자연으로부터 새로운 생리활성물질을 찾기 위한 노력으로 우리나라 서해안 염생습지에 서식하는 비쑥을 채집하여 조추출물을 제조한 후에 HT1080세포내에 생성되는 활성산소종(ROS)에 대한 항산화 활성을 측정한 결과 유의적인 항산화활성이 있음을 확인하였다. 따라서 본 연구에서는 비쑥의 조추출물을 용매극성에 따라 n-hexane, 85% aq.MeOH, n-BuOH, H2O 층으로 분획한 후 각각의 용매분획에 대한 항산화활성과 항암활성을 측정하였으며 또한 각 분획으로부터 이차 대사물질들을 분리하였다.
DPPH radical 소거활성실험에서는 n-BuOH 분획층이 가장 높은 항산화 효과를 보여 주었다. 세포내에 생성된 ROS의 소거와 DNA 산화 억제 실험에서는 85% aq.MeOH과 n-BuOH 분획층이 가장 높은 억제율을 보였다. 그리고 authentic ONOO-와 SIN-1에서 유도된 ONOO-의 소거 활성에서는 85% aq.MeOH 분획층이 가장 높은 소거활성을 보여 주었다.
한편 각 용매 분획물의 인체 암세포들 (HT1080, AGS, HT-29 및 MCF-7)에 대한 증식억제 실험에서는 85% aq.MeOH 분획물이 모든 암세포들에 대해 농도 의존적으로 좋은 암세포 성장 억제 효과를 나타내었고, n-hexane 분획물도 MCF-7를 제외한 나머지 암세포에 대해서 좋은 성장 억제 효과를 나타내었다.
이러한 생리활성을 보인 유기 용매 분획물에서 2차 대사물질들의 분리를 시도하여 n-hexane 분획물에서 α-Amyrin (1), α-Fernenol (2), n-BuOH에서 3,5-dicaffeoyl-epi-quinic acid (3)을 분리하였으며 85% aq.MeOH 분획물에서 새로운 화합물인 1-(3-acetyl-4-hydroxyphenyl)-3-hydroxy-3-methyl-1-butanone (4)을 분리하였다.Content
List of Schemes
List of Tables
List of Figures
List of Abbreviations
Abstract
1. Introduction
2. Materials and Method
2.1 Plant Material
2.2 General Experimental Procedure
2.3 Extraction and Isolation of Artemisia scoparia
2.3.1 Extraction and Fractionation
2.3.2 Isolation of Compounds
2.4 Antioxidant Effects
2.4.1 DPPH radical Scavenging Activity
2.4.2 Peroxynitrite Scavenging Activity
2.4.3 Cell Culture
2.4.4 Measurement of Cytotoxicity using MTT assay
2.4.5 Determination of Intracellular Formation of Reactive Oxygen Species (ROS) using DCFH-DA labelling
2.4.6 Genomic DNA Extraction and Determination of Radical Mediated DNA damage
2.5 Anticancer Activity assay
2.5.1 Cell Cultures and Inhibition of Cancer Cell Proliferation
2.6 Antiinflammatory Activity assay
2.6.1 Cell Culture
2.6.2 Measurement of Cytotoxicity using MTT assay
2.6.3 Determination of Nitrite Oxide (NO) Production
3. Results and Discussion
3.1 Isolation and Structure Determination of Compounds
3.2 Antioxidant Effects
3.2.1 DPPH radical Scavenging Activity
3.2.2 Peroxynitrite Scavenging Activity
3.2.3 Determination of Intracellular Formation of ROS using DCF-DA Labeling
3.2.4 Genomic DNA Extraction and Measurement Genomic DNA Oxidation
3.3 Antiproliferative Effects of Crude Extract and Its Fractions from Artemisia scoparia in Cancer Cells
3.3.1 Effects of Crude Extract and Its Fractions on Cancer Cell Growth
3.4. Inhibitory Effect of Nitric Oxide (NO) Production
4. Conclusion
Acknowledgement
Reference
Appendi
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koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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No full textSupplemental material, sj-docx-1-tej-10.1177_20417314231226105 for Therapeutic potential of luteolin-loaded poly(lactic-co-glycolic acid)/modified magnesium hydroxide microsphere in functional thermosensitive hydrogel for treating neuropathic pain by So-Yeon Park, Joon Hyuk Jung, Da-Seul Kim, Jun-Kyu Lee, Byeong Gwan Song, Hae Eun Shin, Ji-Won Jung, Seung-Woon Baek, Seungkwon You, Inbo Han and Dong Keun Han in Journal of Tissue Engineering</p
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No full textSupplemental material, sj-tif-2-tej-10.1177_20417314231226105 for Therapeutic potential of luteolin-loaded poly(lactic-co-glycolic acid)/modified magnesium hydroxide microsphere in functional thermosensitive hydrogel for treating neuropathic pain by So-Yeon Park, Joon Hyuk Jung, Da-Seul Kim, Jun-Kyu Lee, Byeong Gwan Song, Hae Eun Shin, Ji-Won Jung, Seung-Woon Baek, Seungkwon You, Inbo Han and Dong Keun Han in Journal of Tissue Engineering</p
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