• 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.

• Journal of Microbiology and Biotechnology
• /
• 제8권3호
• /
• pp.237-244
• /
• 1998

A study was carried out to elucidate the relation between the production of flavonol glycosides and the change of phenylalanine ammonia-lyase activity in cell suspension cultures of Ginkgo biloba by the unassisted and synergistic effects of various factors. The quercetin production showed a mixed-growth-associated pattern in cell suspension cultures. Fluorescent light and UV radiation increased phenylalanine ammonia-lyase (PAL) activity, and resulted in the increase of the production of quercetin and kaempferol ten- and four-fold, respectively, as compared to that obtained in the normal culture condition. The cell growth of Ginkgo biloba was enhanced .at higher temperatures whereas the quercetin production was at its maximum at low temperatures. Moreover, the quercetin production was increased by temperature change during the culture period. In particular, the quercetin production was at the highest level when the culture temperature was elevated from $10^{\circ}C\;to\;30^{\circ}C$. The addition of phenylalanine as a precursor in the culture medium stimulated an 8-fold increase in the production of quercetin; the addition of naringenin caused a l0-fold increase. The quercetin production was also greatly increased by feeding enzyme cofactors such as 2-ketoglutarate and ascorbic acid in the culture medium, but specific PAL activity was not increased except with phenylalanine feeding. The synergistic effect of UV radiation and naringenin feeding was observed, resulting in the increase of flavonol glycoside production at a rate higher than in any other case investigated.

• 한국약용작물학회지
• /
• 제19권4호
• /
• pp.251-256
• /
• 2011

The leaves of Hippophae rhamnoides were extracted with methanol and then further fractioned with hexane, ethyl acetate, butanol and water in order to investigate biological activity. Two flavonol glycosides were isolated and identified from ethyl acetate soluble fraction, which showed the strongest antioxidant activity ($RC_{50}$ = 4.33 ${\mu}g/ml$). Isolated two compounds have shown strong free radical scavenging activity. Especially, quercetin 3-O-glucoside ($RC_{50}$ = 2.60 ${\mu}g/ml$) was more active than ${\alpha}$-tocopherol ($RC_{50}$ = 4.67 ${\mu}g/ml$). Total phenol and flavonoid contents were the highest to 4.17 and 1.14 mg/ml in the ethyl acetate soluble fraction. In addition, ethyl acetate soluble fraction was shown to the strongest ${\alpha}$-glucosidase inhibitory activity ($IC_{50}$ = 137.88 ${\mu}g/ml$) among the fractions. The results suggest that leaves of H. rhamnoides could be a potential source of natural antioxidant.

• Preventive Nutrition and Food Science
• /
• 제14권2호
• /
• pp.109-115
• /
• 2009

The principal objective of this study was to assess the radical scavenging activities and total polyphenols, flavonoids, and flavonol contents of takju, a Korean traditional rice wine. The antioxidant properties of the wine and takju samples were evaluated using five distinct assays: specifically, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-di-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS); hydroxyl; superoxide anion; and nitric oxide (NO) radical-scavenging activity assays. In this study, the takju evidenced strong scavenging activities against the hydroxyl, superoxide anion, and NO radicals. Furthermore, the total polyphenol contents of T-2 were similar to those previously observed in white wine (p<0.05). However, the flavonoids and flavonol contents of all takju samples were significantly (p<0.05) lower than that of white wine. The results of this study show that takju possesses a powerful radical scavenging activity against a variety of oxidative systems. The findings of this study also indicate that takju should be considered a useful antioxidant, and that their functional compound reduces oxidative stress.

• Natural Product Sciences
• /
• 제24권3호
• /
• pp.213-218
• /
• 2018

Chemical investigation of the plant Tristemma hirtum P. Beauv (Melastomataceae) resulted to the isolation of a new flavonol glycoside named quercetin-7-O-${\alpha}$-D-arabinofuranoside (1), together with nine known compounds including 3'-hexadecanoyl-2'-(9aZ)-tetradecanoyl-glycerol 1'-O-[${\beta}$-D-galactopyranosyl-(1'' ${\rightarrow}$ 6'')-${\alpha}$-D-galactopyranoside] (2), arjunolic acid (3), ${\beta}$-sitosterol-3-O-${\beta}$-D-glucopyranoside (4), terminolic acid (5), quercetin (6), asiatic acid (7), maslinic acid (8), $1{\beta}$-O-galloylpedunculagin (9) and 6-hydroxyapigenin 7-O-${\beta}$-D-glucopyranoside (10) from the methanol extract using normal and reversed phase column chromatography. The structures of these compounds were determined by comprehensive interpretation of their spectral data mainly including 1D- 2D-NMR ($^1H-^1H$ COSY, HSQC, and HMBC) spectroscopic and ESI-TOF-MS mass spectrometric analysis.

• 생약학회지
• /
• 제30권2호
• /
• pp.202-206
• /
• 1999

The MeOH extracts obtained from the leaves of Eucommia ulmoides were solvent-fractionated with EtOAc, n-BuOH, and $H_20$, successively. From the EtOAc extract showing Grab2-Shc inhibitory activity, a flavonol and a lignan compounds were isolated through repeated silica gel column chromatographies. By interpretation of several spectral data and adaptation of acetylation method, the chemical structures of the compounds were determined as 5,7,3',4'-tetrahydroxy-flavonol (quercetin), and 4,4',8',9-tetrahydroxy-3,3'-dimethoxy-7,9'-cyclolignan {(-)-olivil)}, respectively. The compounds exhibited $IC_{50}$ values in Grb2-Shc inhibitory activity to be 93 and $210\;{\mu}mole/l$, respectively.

• 한국잠사곤충학회지
• /
• 제40권1호
• /
• pp.1-7
• /
• 1998

The morphological and chemical characteristics of leaves and fruits were observed in the three mulberry varieties, including Daeryugppong(Morus Lhou(Ser.) koidz), Kugsang 20(Morus Lhou(Ser.) koidz) and Cataneo(Morus alba L.). The leaf development in spring was earliest in Cataneo and latest in Kugsang. Content of total nitrogen and Mg in leaf was the highest in Cataneo while that of P2O5, K and Ca in Daeryukppong. Flowers started to bloom from May 8 and in full bloom around May 15. Mature fruits began to set from June 10 to 15 and lasted by July 10 in Cataneo. Average fruit weight was heaviest in Kugsang 20(3.52 g/fruit), while lowest in Daeryukppong(1.61 g/fruit). In fruits, glucose and fructose were the major sugars. Citric acid was the most abundant organic acid in three varieties with its average content from 0.8 to 0.14%. The major pigment in fruit was anthocyanin and its content varied among varieties. The stability of anthocyanin was evaluated under various pH, temperature, and sugar concentrations. Rutin was the major flavonol glycoside present in fruits and its content varied from 0.92 to 3.36 mg/gDW. Other flavonol glycosides such as isoquercitrin and quercitrin were also detected in fruit.

• Bulletin of the Korean Chemical Society
• /
• 제35권12호
• /
• pp.3447-3452
• /
• 2014

Detailed chemical investigation of Boscia senegalensis (Per) Lam. ex Poir. led to the isolation of one new flavonol glycoside, rhamnocitrin-3-O-${\beta}$-$\small{D}$-(6"-O-E-feruloyl)-glucopyranoside named bosenegaloside A (1), with seven known compounds, rhamnocitrin-3-O-${\beta}$-$\small{D}$-(6"-O-E-p-coumaroyl)-glucopyranoside (2), rhamnocitrin-3-O-${\beta}$-$\small{D}$-glucopyranoside (3), 3,4,5-trimethoxyphenol-${\beta}$-$\small{D}$-glucopyrinoside (4), lasianthionoside A (5), 3,7-dimethyl-1-octene-3,6,7-triol-6-O-${\beta}$-$\small{D}$-glucopyranoside (6), syringin (7), and austroside B (8). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of these data with previously published results. The inhibitory activity of the isolated compounds on soluble epoxide hydrolase (sEH) was assessed. Compounds 1-3 potently inhibited sEH activity with $IC_{50}$ values of $12.8{\pm}0.5$, $18.4{\pm}0.2$, and $11.3{\pm}0.9{\mu}M$, respectively.

• Natural Product Sciences
• /
• 제14권4호
• /
• pp.233-238
• /
• 2008

The aerial parts of Epimedium koreanum Nakai have been used to stimulate hormone secretion in treating impotence. Ten flavonol glycosides, 3,4,5-trihydroxy-8-prenylflavone 7-O-[${\beta}$-D-glucopyranosyl($1{\rightarrow}2$)-${\beta}$-D-glucopyranoside] (1), hyperoside (2), icarisid II (3), 2"-O-Rhamnosylicarisid II (4), epimedin A (5), epimedin B (6), epimedin C (7), icariin (8), hexandraside E (9), and epimedoside A (10) were isolated from the an ethylacetate soluble extracts of the aerial parts of Epimedium koreanum Nakai through activity-monitord fractionation and isolation method. The structures of compounds 1 - 10 were elucidated by high resolution fast atom bombardment mass spectrometry and two dimentional nuclear magnetic resonance spectroscopy analysis. Compounds 1 and 4 showed potent antioxidant activity, with $IC_{50}$ values of 19.7 and 11.5 ${\mu}g$/mL and 88.2 and 90.5 ${\mu}M$, respectively.

• Archives of Pharmacal Research
• /
• 제28권7호
• /
• pp.791-798
• /
• 2005

The hepatoprotective activity of flavonol glycosides rich fraction (F-2), prepared from 70% alcohol extract of the aerial parts of V calcarata Desf., was evaluated in a rat model with a liver injury induced by daily oral administration of $CCl_4$ (100 mg/kg, b.w) for four weeks. Treatment of the animals with F-2 using a dose of (25 mg/kg, b.w) during the induction of hepatic damage by $CCl_4$ significantly reduced the indices of liver injuries. The hepatoprotective effects of F-2 significantly reduced the elevated levels of the following serum enzymes: alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH). The antioxidant activity of F-2 markedly ameliorated the antioxidant parameters including glutathione (GSH) content, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), plasma catalase (CAT) and packed erythrocytes glucose-6-phosphate dehydrogenase (G6PDH) to be comparable with normal control levels. In addition, it normalized liver malondialdehyde (MDA) levels and creatinine concentration. Chromatographic purification of F-2 resulted in the isolation of two flavonol glycosides that rarely occur in the plant kingdom, identified as quercetin-3,5-di-O-$\beta$-D-diglucoside (5) and kaempferol-3,5-di-O-$\beta$-D-diglucoside (4) in addition to the three known compounds identified as quercetin-3-O-$\alpha$-L-rhamnosyl- (${\rightarrow}6$)-$\beta$-D-glucoside [rutin, 3], quercetin-3-O-$\beta$-D-glucoside [isoquercitrin, 2] and kaempferol-3-O-$\beta$-D-glucoside [astragalin, 1]. These compounds were identified based on interpretation of their physical, chemical, and spectral data. Moreover, the spectrophotometric estimation of the flavonoids content revealed that the aerial parts of the plant contain an appreciable amount of flavonoids (0.89%) calculated as rutin. The data obtained from this study revealed that the flavonol glycosides of F-2 protect the rat liver from hepatic damage induced by $CCl_4$ through inhibition of lipid peroxidation caused by $CCl_4$ reactive free radicals.