• Natural Product Sciences
• /
• v.21 no.3
• /
• pp.170-175
• /
• 2015

The present study aims to detect the rare flavonoids isolated from the leaves of Persicaria glabra. The known flavonoids: quercetin (1), isorhamnetin (2), avicularin (3) and new one isorhamnetin-3-O-α-L-(6''-E-p-coumaroyl)-rhamnoside (4) were identified by HPLC, UV, IR and NMR. P. glabra has used traditionally for its analgesic, anti-inflammatory and anti-rheumatic properties. To find out the ingredients responsible for the efficiency of this plant, we have used to study the anti-microbial and anti-inflammatory activities of different extracts.

• Korean Journal of Food Science and Technology
• /
• v.31 no.3
• /
• pp.815-822
• /
• 1999

Twenty one flavonoids were isolated from ethyl acetate layer of aqueaus EtOH extracts of Artemisia vulgaris and identified as tricin, jaceosidine, eupafolin, diosmetin, chrysoeriol, homoeriodictyol, isorhamnetin, apigenin, eriodictyol, luteolin, luteolin 7-glucoside, kaempferol 3-glucoside, kaempferol 7-glucoside, kaempferol 3-rhamnoside, kaempferol 3-rutinside, quercetin, quercetin 3-glucoside, quercetin 3-galactoside, quercetrin, quercetin 7-glucoside, rutin, and vietexin. The inhibitory activity for all purified flavonoids were examined against lipid peroxidation in rat liver microsome. All examined flavonoids showed considerable antioxidant activity. Among them, $IC_{50}$ value of apigenin, luteolin, isorhamnetin, quercetin, and eriodictyol were showed higher than that of vitamin E used as positive control. And methoxylated flavonoids, tricin, eupafolin, jaceosidine, diosmetin, and isorhamnetin showed considerable antioxidant activity. Each $IC_{50}$ values were shown at 0.9, 1.0, 1.4, 1.0, and $0.7\;{\mu}g/mL$, respectively.

• Archives of Pharmacal Research
• /
• v.27 no.1
• /
• pp.44-47
• /
• 2004

Loranthus tanakae Fr. et Sav. (Loranthaceae) is a species of mistletoe, a semiparasitic plant growing on the branches of Quercus and Betula species as host trees. In our ongoing search for bioactive compounds from endemic species in Korea, we have investigated to isolate the chemical constituents responsible for the antitumor effect of the MeOH extract of L. tanakae. The ethyl acetate soluble part of the MeOH extract demonstrated a marginal inhibition on the proliferation of the tumor cell lines such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system), and HCT-15 (colon) in vitro. Thus, the activity-guided isolation procedure upon the ethyl acetate soluble part of the extract has been carried out and finally four flavonoid rhamnopyranosides (1-4) were isolated as active principle. The structures of 1-4 were elucidated by the physicochemical and spectral data as rhamnetin 3-O-$\alpha$-L-rhamnoside (1), quercetin 3-O-$\alpha$-L-rhamnoside (2), rhamnocitrin 3-O-$\alpha$rhamnoside (3), and kaempferol 3-O-$\alpha$-L-rhamnoside (4).

• Korean Journal of Agricultural Science
• /
• v.44 no.1
• /
• pp.104-113
• /
• 2017

Anthocyanins contained in Rhododendron schlippenbachii (royal azalea) are expressed in a variety of colors and affect flower colors. R. schlippenbachii flowers of seven colors (white, red group: pink, deep pink, red, purple group: light purple, purple, deep purple) were collected from the garden around KT&G building in the college of agriculture and life science. Seven types of anthocyanins [cyanidin 3-O-diglucoside, cyanidin 3-O-arabinoside-5-O-glucoside, cyanidin 3-O-galactoside, peonidin 3-O-arabinoside-5-O-glucoside, cyanidin 3-O-glucoside, cyanidin 3-O-(6"-O-malonyl) arabinoside, cyanidin 3-O-(6"-O-coumaroyl) glucoside] turned out to be from the cyanidin and peonidin series in R. schlippenbachii flowers. Also, seven types of flavonols [azaleatin 3-O-glucoside, azaleatin 3-O-arabinoside, azaleatin 3-O-rhamnoside, quercetin 3-O-galacatoside, quercetin 3-O-glucoside, quercetin 3-O-arabinoside, quercetin 3-O-rhamnoside] were identified in R. schlippenbachii flowers. Total anthocyanin amounts decreased in R. schlippenbachii flowers in the following order: 'deep pink' (8.07) > 'red' (6.37) > 'pink' (5.35) > 'deep purple' (0.78) > 'purple' (0.43) > 'light purple' ($0.22mg{\cdot}g^{-1}$ dry weight, DW) > 'white' (not detected). Total flavonol amounts decreased in the following order: 'pink' (97.78) > 'deep pink' (63.79) > 'deep purple' (61.98) > 'white' (57.58) > 'light purple' (47.06) > 'purple' (46.76) > 'red' ($7.60mg{\cdot}g^{-1}$ dry weight, DW). This study provided the quantitative and qualitative information for the variation of anthocyanin and flavonol compounds in R. schlippenbachii flowers. Furthermore, this information can contribute to the identification of anthocyanin and flavonol compounds in other Rhododendron flowers.

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.298.2-298.2
• /
• 2002

Bioflavonoids are semi-essential food components that are ubiquitously present in nature. It has been reported that flavonoids act as anti-oxidant as well as anti-cancer agents. Quercetin is one of the most widely distributed bioflavonoids in the plant kingdom. The goal of this study was to investigate effects of quercetin analogs extracted from Lindera erythrocarpa, quercetin 3-O-${\alpha}$-arabinofuranoside and quercetin 3-O-${\alpha}$-L -rhamnoside, on oxidatie stress-induced cell death. (omitted)

• Biomolecules & Therapeutics
• /
• v.7 no.4
• /
• pp.371-376
• /
• 1999

By cytotoxicity screening of the 65 Korean medicinal plants against leukemia L1210 and P388D$_{1}$ cell line using the MTT assay in vitro, Albizzia julibrissin was studied. This plant was extracted with MeOH and MeOH extract was solvent-fractionated with CHCl$_{3}$, EtOAc and n-BuOH in sequence. Each fraction by various solvents system was purified by column chromatography and preparative TLC, and four compounds were isolated. The structure of each compound was deduced from UV, IR, $^{1}$H-HMR, $^{13}$ C-NMR and CI-MS spectral data. The cytotoxic activity ($IC_{50}$/_ of the compounds, quercetin-3-rhamnoside, 4',5,7-trihydroxyfla-van-3-glucoside, spinasterol-3-glucoside and acacic acid lactone, were evaluated as 5 $\mu\textrm{g}$/ml, 2$\mu\textrm{g}$/ml, 1 $\mu\textrm{g}$/ml against L1210 and as 9$\mu\textrm{g}$/ml, 10$\mu\textrm{g}$/ml, 1.5 $\mu\textrm{g}$/ml, 1.5 $\mu\textrm{g}$/ml and 0.9 $\mu\textrm{g}$/ml against P388D$_{1}$, respectively.

• Horticulture, Environment, and Biotechnology : HEB
• /
• v.59 no.6
• /
• pp.909-917
• /
• 2018

Quercetin and its glycoside derivatives were identified and quantified using high-performance liquid chromatograph (HPLC) and liquid chromatograph/mass spectrometer/mass spectrometer (LC/MS/MS) in the leaves, flowers, and fruits of 22 Malus genotypes. In all genotypes, small amounts of quercetin aglycone were present, with water-soluble glycoside forms were the most abundant in different Malus plant tissues, including quercetin-3-galactoside, quercetin-3-rutinoside, quercetin-3-glucoside, quercetin-3-xyloside, quercetin-3-arabinoside, and quercetin-3-rhamnoside. Among these six quercetin glycosides, quercetin-3-galactoside was the common form in Malus plants, except in the leaves and flowers of M. ceracifolia and M. magdeburgensis, and in the fruits of M. micromalus 'Haihong Fruit', where there was a higher concentration of quercetin3-glucoside. Among the different tissues tested, leaves contained the highest concentration of quercetin and its glycosides, while fruits contained the lowest concentrations of these compounds. Among the genotypes we analyzed, no specific genotype consistently contained the highest concentration of quercetin and its glycoside derivatives. M. domestica 'Honeycrisp' had the highest total compound concentration (approximately $1600mg\;kg^{-1}$), whereas M. hupehensis contained the lowest in its fruits. In contrast, the concentration of total quercetin and its glycosides was more than $5000mg\;kg^{-1}$ in the leaves of eight genotypes and greater than $2500mg\;kg^{-1}$ in the flowers of seven species. In general, the concentration of quercetin and its glycoside derivatives depended on the species and tissue type. These results may provide useful information for the evaluation and selection of edible Malus fruits and the materials for quercetin glycoside extraction.

• Korean Journal of Pharmacognosy
• /
• v.27 no.3
• /
• pp.238-245
• /
• 1996

The activity guided fractionation of $CH_2Cl_2$ soluble part of Platycarya strobilacea leaves(Juglandaceae) has led to the isolation of eight active principles, identified as 5-hydroxy-2-methoxy-1,4-naphthoquinone(1), ursolic acid(2), gallic acid(3), 4,8-dihydroxynaphthalene $1-O-{\beta}-_D-glucoside(4)$, eriodictyol(5), quercetin $3-O-(2'-O-galloyl)-{\beta}-_D-glucoside(6)$. quercetin $3-O-(2'-O-galloyl)-{\beta}-_D-galactoside(7)$ and quercetin $3-O-{\alpha}-_L-rhamnoside(8)$ by the means of chemical and spectral evidence, respectively.

• Natural Product Sciences
• /
• v.23 no.2
• /
• pp.139-145
• /
• 2017

Seven flavonoid compounds, kaempferol (1), quercetin (2), quercetin-3-O-${\beta}$-D-glucopyranoside (3), kaempferol-3-O-${\beta}$-D-glucopyranoside (4), kaempferol-3-O-${\alpha}$-L-rhamnoside (5), quercetin-3-O-sophoroside (6) and quercetin-3-O-rutinoside (7), were isolated from the methanolic extract of leaves of Kalanchoe prolifera. Compounds 1-7 were isolated for first time from this plant. These compounds were evaluated their cytotoxic activity against P-388 murine leukimia cells in vitro. Among those compounds kaempferol (1) and quercetin (2) showed strongest cytotoxic activity with $IC_{50}$ values of $4.45{\pm}0.05$ and $6.28{\pm}0.02{\mu}g/mL$, respectively.

• YAKHAK HOEJI
• /
• v.42 no.4
• /
• pp.414-421
• /
• 1998

In order to compare the suppressive effect of quercetin and its glycosides, such as quercitrin (quercetin-3-rhamnoside), isoquercitrin (quercetin-3-glucoside), hyperin (querceti n-3-galactoside)and rutin (quercetin-3-rhamnosyl glucoside), on the genotocicity by benzo(a)pyrene(B(a)P), in vitro sister chromatid exchange(SCE) test using mouse spleen lymphocytes and in vivo micronucleus test using mouse peripheral blood were performed. B(a)P-induced SCEs in vitro were slightly decreased by the simultaneous treatment of quercetin and its glycosides, although there was no significant decrease. On the other hand, MNU induced micronucleated reticulocytes(MNRL7s) in vivo were significantly decreased with a dose-dependent manner in all compounds tested. However, there were no differences between quercetin aglycone and glycosides in the suppressive effects under experimental condition of this study. To elucidate, the action mechanism of quercetin aglycone and its glycosides against B(a)P-induced genotoxicity, the assay of DNA binding with B(a)P was studied. Quercetin aglycone and its glycosides inhibited B(a)P metabolism in the presence of S-9 mix and decreased the B(a)P/DNA binding in the calf thymus DNA with S-9 mix. These results suggest that antigenotoxicity of quercetin antiglycosides on B(a)P-induced genotoxicity is due to decrease of DNA binding with B(a)P through the inhibition of metabolism with B(a)P in the calf thymus DNA. Therefore, quercetin and its glycosides may act as an antigenotoxicity agent and may be useful as a chemopreventive agent of polycyclic aromaic hydrocarbons like B(a)P.