Antioxidant Activities of Phenolic Constituents from Juncus diastrophanthus = : 별날개골풀의 항산화 페놀성 성분

다국어 초록 (Multilingual Abstract)

ABSTRACT


Antioxidant Activities of Phenolic Constituents from Juncus diastrophanthus

Tao, Chao
Lab. of Natural Products
College of Pharmacy
Graduate School of
Woosuk University

Juncus diastrophanthus (Juncaceae) grows in wetlands as an annual plant in Korea, Japan and China. This plant is a monocotyledones in the genus Juncus.　But， up to now, phytochemical and pharmacological studies of this plant has been performed　little.
Recently, the synthetic antioxidants like butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and tertiary butyl hydroquinone (TBHQ) have been limited to use because of their possible toxicity. Naturally, demand for safer and more effective natural antioxidants has been directed our attention.
In the course of screening for antioxidative effects from natural plants in Korea by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH), ethyl acetate soluble fraction of J. diastrophanthus was found to show a potent antioxidant activity. Subsequent activity-guided chromatography of ethyl acetate soluble fraction of J. diastrophanthus led to the isolation of five compounds. The chemical structures of the isolated compounds were elucidated as methyl 3,5-di-O-caffeoylquinate (1), luteolin-7-O-glucopyranoside (2), methyl 4,5-di-O-caffeoylquinate (3), quercetin-3-O-β-arabino- pyranoside (4), and methyl 3,4-di-O-caffeoylquinate (5) by spectroscopic techniques.
Compounds 1-4 showed the significant antioxidative effects on DPPH, and the significant riboflavin- and xanthine-originated superoxide quenching activities. Those five compounds were isolated for the first time from this plant.

국문 초록 (Abstract)

Korean Abstract

별날개골풀의 항산화 페놀성 성분


우석대학교 대학원
약학과 약학전공
도 초

　골풀과(Juncaceae)에 속하는 별날개골풀(Juncus diastrophanthus Buchenau)은 습지에서 자라며 한국과 중국, 일본에 분포한다. 근경은 짧고 뿌리는 백색이다. 꽃은 6∼7월에 녹색으로 원줄기 에서 피며, 열매는 세모진 삭과(果)를 맺는다. 높이 20∼40cm, 폭 2∼3mm로서 날개가 있고 화피편은 선형으로 3맥이 있고 끝이 뾰족하며 내외편(內外片)이 거의 같다.
　골풀속은 전통적으로 골풀목, 골풀과에 속하는 식물군이다.세계적으로 널리 분포하는　골풀속은 약 300여 분류군이 있다.이 식물에 대한 문헌조사 결과 식물화학적 또는 약리학적 연구는 많지 않은 것으로 나타나 항산화 활성 탐색과 더불어 기초적인 식물 화학적 성분 연구의 일환으로 본 연구를 수행하였다.
별날개골풀의 methanol추출물을 n-hexane, methylene 　　　chloride, ethyl acetate, n-BuOH 및 물로 계통 분획한 후, 　　1,1-diphenyl-2-picrylhydrazyl(DPPH) free radical 소거 　　활성이 가장 강하게 나타났던 ethyl acetate 분획에서 5종의 화합물을 단리하였다. 단리된 화합물을 물리화학적 성상과 기기분석 spectral data를 통해 구조를 확인한 결과　methyl 3,5-di-O-caffeoylquinate(1), luteolin-7-O-glucopyranoside(2), methyl 4,5-di-O-caffeoylquinate(3), quercetin-3-O-β-arabino- pyranoside(4) 및 methyl 3,4-di-O-caffeoylquinate(5)로 각각 확인·동정되었다.
이상 ５종의 화합물은 본 식물에서는 처음으로 보고되는 것이며, 분리된 화합물 5종은 모두 DPPH radical 소거 효능을 보여주었고, quinic acid유도체가 flavonoid화합물보다 다소 강한 은 riboflavin과 xanthine으로 유래된 superoxide에 대해 강한 소거 효능을 보여 주었다.

목차 (Table of Contents)

• CONTENTS
• List of Schemes vii
• List of Figures vii
• List of Abbreviations viii Abstract 1 I. INTRODUCTION 3 II. MATERIALS AND METHODS 5
• 1. General experimental procedures 5
• 2. Plant material 5
• 3. Extraction and isolation 6
• 3-1. Extraction and solvent fractionation 6
• 3-2. Isolation of compounds 6
• 3-2-1. Compound 1 7
• 3-2-2. Compound 2 8
• 3-2-3. Compound 3 9
• 3-2-4. Compound 4 10
• 3-2-5. Compound 5 11
• 4. Antioxidative effect assay 12
• 4-1. DPPH radical scavenging assay 12
• 4-2. Riboflavin-originated superoxide quenching assay 12
• 4-3. Xanthine-originated superoxide quenching assay 13
• III. RESULTS AND DISCUSSION 14
• 1. Structures of isolated compounds 14
• 1-1. Compound 1 14
• 1-2. Compound 2 15
• 1-3. Compound 3 16
• 1-4. Compound 4 16
• 1-5. Compound 5 17
• 2. Antioxidative effect 18
• 2-1. DPPH radical scavenging effect 18
• 2-2. Riboflavin-originated superoxide quenching activity 18
• 2-3. Xanthine-originated superoxide quenching activity 19
• IV. CONCLUSION 20
• References 21
• Korean abstract 25