• 생약학회지
• /
• 제43권2호
• /
• pp.101-106
• /
• 2012

The anti-hyperlipidemic effect of Houttuynia cordata was assessed in poloxamer-407 induced hyperlipidemic mice model. The butanol fraction and its isolated compound, quercetin-3-O-rhamnoside, significantly reduced the blood triglyceride and total-cholesterol level and increased the blood HDL-cholesterol level. They also showed the significant reductive effect on the blood AST and ALT level, rising in proportion to the liver damage, in hyperlipidemic mice.

• 대한본초학회지
• /
• 제24권4호
• /
• pp.137-142
• /
• 2009

Objectives : This study was performed to investigate the antioxidant activities of isolated compounds from the shoot of Aralia elata. Methods : The methanol extract from the shoot of Aralia elata was fractionated into ethyl acetate, n-BuOH and $H_2O$ layers through solvent fractionation. Repeated silica gel, ODS column chromatography of n-BuOH layer afforded four flavonol glycosides. Their antioxidant activity was determined by measuring free radical scavenging activity by DPPH, ABTS and superoxide dismutase (SOD) like activity assay. Results : They were identified as quercetin 3,7-di-O-$\alpha$-rhamnopyranoside (1), quercetin 3-O-$\beta$-D-galactoside-7-O-$\alpha$-L-rhamnoside (2), kaempferol 3-O-$\beta$-glucosyl($1{\rightarrow}2$)-$\alpha$-rhamnoside-7-O-$\alpha$-rhamnoside (3) and quercetin 3-O-$\beta$-glucosyl($1{\rightarrow}2$)-$\alpha$-rhamnoside-7-O-$\beta$-rhamnoside (4) on the basis of spectroscopic data. The result showed that 1 is the most active compound in the DPPH and ABTS radical scavenging test. Conclusions : Isolated Compounds from the shoot of Aralia elata showed anti-oxidative effect.

• Natural Product Sciences
• /
• 제10권5호
• /
• pp.244-247
• /
• 2004

The inhibitory effects of the leaves of Eucalyptus darylmpleana (Myrtaceae) on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was examined. The scavenging effect of the ethyl acetate fraction of Eucalyptus darylmpleana leaves on DPPH radical was stronger than the other fractions, and further purified by silica gel and Sephadex LH-20 column chromatography. 3,4-Dihydroxybenzoic acid, gallic acid, quercetin, quercetin $3-O-{\alpha}-_L-rhamnoside$, quercetin $3-O-{\beta}-_D-glucoside$ and quercetin 3-O-rutinoside were isolated and elucidated by spectroscopic data. Among these components, gallic acid and quercetin $3-O-{\alpha}-_L-rhamnoside$ exhibited potent scavenging activities on DPPH radical with $IC_{50}$ values of 6.02 and $5.54\;{\mu}M$, respectively.

• Journal of Applied Biological Chemistry
• /
• 제65권4호
• /
• pp.277-286
• /
• 2022

Schizophragma hydrangeoides (S. hydrangeoides) is a vine endogenous to Jeju Island and Ulleungdo, where it grows attached to the foothills and rock surfaces. Previous research has mostly focused on the whitening effect of S. hydrangeoides leaf extract. In this study, we investigated S. hydrangeoides leaf extract further, and detected four phytochemicals in the extract: chlorogenic acid, quercetin-3-O-glucosyl-(1-2)-rhamnoside, quercetin-3-O-xylosyl-(1-2)-rhamnoside, and quercitrin. We pretreated human dermal fibroblast (HDFn) cells with previously established concentrations of the four compounds for 1 h before ultraviolet A (UVA) irradiation. Among the four compounds, quercetin-3-O-glucosyl-(1-2)-rhamnoside (Q-3-GR) best inhibited matrix metalloproteinase-1 (MMP-1) levels. Thus, we investigated the protective effects of Q-3-GR on photoaging and its underlying mechanisms. Q-3-GR significantly reduced MMP-1 production and inhibited MMP-1 protein expression in UVA-irradiated HDFn cells. Furthermore, Q-3-GR increased procollagen type I production and protein expression. Q-3-GR exerted its anti-photoaging effects by downregulating the mitogen-activated protein kinase/ activator protein-1 signaling pathway, and upregulating the transforming growth factor-β/Smad signaling pathway. Thus, S. hydrangeoides leaf-derived Q-3-GR is a potential potent cosmetic ingredient for UV-induced skin aging.

• 생명과학회지
• /
• 제16권3호
• /
• pp.442-446
• /
• 2006

참죽나무는 멀구슬과 나무로서 한국과 중국에 널리 분포하고 있다. 한방에서는 장염(腸炎), 이질(痢疾), 개선(疥癬) 등의 치료에 이용되고 있다. 본 연구는 참죽나무 잎에서 3종의 flavonol glycosides를 분리하여 NMR을 통해 구조를 확인한 결과, kaempferol-3-O-rhamnoside (1), quercetin-3-O-rhamnoside (2)와 quercetin-3-O-glucoside(3)로 구조 동정되었다. 분리된 화합물들의 생리활성은 matrix metalloproteinase-2 저해 활성과 인체암 세포주에 대한 세포독성과 apoptosis실험을 통하여 항암효과를 조사하였다. 그 결과 인체암 세포주에 대한 세포독성과 apoptosis 저해활성은 나타내지 않았으나, MMP-2활성저해 조사에서는 강한 저해 효과를 나타내었다. 특히 quercetin-3-O-glucoside는 암세포에 직접적인 독성을 보이는 것이 아니라 암의 침윤과 전이에 특이적으로 작용하는 물질로 보여진다.

• 한국약용작물학회지
• /
• 제13권6호
• /
• pp.250-254
• /
• 2005

Night-break, 일장조절, 월동가온 실험으로부터 얻어진 바위솔에 포함된 flavonol glycoside, $kaempferol-3-O-{\beta}-D-glucoside$(1), $kaempferol-3-O-{\beta}-D-glactoside$ (2), $kaempferol-3-O-{\beta}-D-rhamnoside$ (3), $quercetin-3-O-{\beta}-D-glucoside$ (4) and $quercetin-3-O-{\alpha}-D-rhamnoside$ (5)의 함량이 분석되었으며 자연산 바위솔의 함량과 비교되었다. 월동가온 시험에서 얻은 flavonol glycoside 1-5의 함량은 자연산보다 감소하였으며 일장조절 실험 및 night-break 시험에서 얻은 flavonol glycoside 함량은 조사한 빛의 양이 증가함에 따라 증가하였다. 월동가온은 flavonol glycoside의 생성에 부정적으로 작용하는 반면 조사되는 빛의 양의 증가와 같은 경작조건은 flayonol glycoside의 생성에 유리하다.

• 대한한의학방제학회지
• /
• 제12권1호
• /
• pp.255-262
• /
• 2004

The inhibitory effect of the aerial parts of Fagopyrum esculentum on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was examined. The n-butanol fraction from the methanol extract of title plant showed stronger inhibitory effect than other fractions on DPPH radical. Two flavonoids were isolated from n-butanol fraction having the potent activity and elucidated as quercetin-3-O-${\alpha}$-L-rhamnoside and quercetin-3-O-rutinoside on the basis of spectral evidence. The $IC_{50}$ values of these compounds on DPPH radical were 6.56 ${\mu}M$ and 8.37 ${\mu}M$, respectively.

• 생약학회지
• /
• 제19권2호
• /
• pp.93-96
• /
• 1988

Three flavonoids were isolated from Epimedium koreanum and identified as quercetin(1), $anhydroicaritin-3-O-{\alpha}-rhamnoside(2)$ and icariin(3) by spectroscopic methods. The former two compounds are the first isolation from this plant.

• Natural Product Sciences
• /
• 제8권4호
• /
• pp.147-151
• /
• 2002

In the course of our work on anti-platelet constituents from plants, eight phenolic compounds, $({\pm})-syringaresinol$ (1), 4-hydroxybenzaldehyde (2), 4-hydroxybenzoic acid (3), vanillic acid (4), 4-hydroxy cinnamic acid (5), quercetin 3-O-rhamnoside (6), rutin (7), and quercetin $3-(2^G-rhamnosylrutinoside)$ (8) were isolated from the methanol extract of the leaves of Magnolia obovata. The compounds were identified based on the spectroscopic data. Compound 2, 3, 5, 6, 7 and 8 were isolated for the first time from genus Magnolia. 1 and 6 showed same order of inhibitory potencies as acetylsalicylic acid (ASA) to rat platelet aggregation induced by all the stimulators tested. The remaining six compounds showed only mild effects.

• Journal of Microbiology and Biotechnology
• /
• 제28권11호
• /
• pp.1859-1864
• /
• 2018

Synthesis of flavonoid glycoside is difficult due to diverse hydroxy groups in flavonoids and sugars. As such, enzymatic synthesis or biotransformation is an approach to solve this problem. In this report, we used stepwise biotransformation to synthesize two quercetin bisglycosides (quercetin 3-O-glucuronic acid 7-O-rhamnoside [Q-GR] and quercetin 3-O-arabinose 7-O-rhamnoside [Q-AR]) because quercetin O-rhamnosides contain antiviral activity. Two sequential enzymatic reactions were required to synthesize these flavonoid glycosides. We first synthesized quercetin 3-O-glucuronic acid [Q-G], and quercetin 3-O-arabinose [Q-A] from quercetin using E. coli harboring specific uridine diphopsphate glycosyltransferase (UGT) and genes for UDP-glucuronic acid and UDP-arabinose, respectively. With each quercetin 3-O-glycoside, rhamnosylation using E. coli harboring UGT and the gene for UDP-rhamnose was conducted. This approach resulted in the production of 44.8 mg/l Q-GR and 45.1 mg/l Q-AR. This stepwise synthesis could be applicable to synthesize various natural product derivatives in case that the final yield of product was low due to the multistep reaction in one cell or when sequential synthesis is necessary in order to reduce the synthesis of byproducts.