• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.361-366
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• 2019

Isorhamnetin 3-O-glucoside, a member of the flavonol group, has been reported to be effective for inflammatory and ulcer, as well as to alleviate diabetic complications such as neuropathy, nephropathy and retinopathy. Isorhamnetin 3-O-glucoside has been extracted from several plants. Biotransformation is a valuable tool, which is used to produce value-added chemicals with inexpensive compounds. To synthesis isorhamnetin 3-O-glucoside from quercetin, two genes (PGT E82L and ROMT-9) were introduced into Escherichia coli, respectively. In order to synthesis isorhamnetin 3-O-glucoside from quercetin, a co-culture fermentation system was developed by optimizing the medium and temperature for biotransformation, the cell mix ratio, Isopropyl-β-ᴅ-thiogalactoside induction time, and quercetin feed concentration. Finally, isorhamnetin 3-O-glucoside was biosynthesized up to 181.2 mg/L under the optimized biotransformation condition, which was higher 4.7 times than previously reported (39.6 mg/L).

• Journal of Applied Biological Chemistry
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• v.50 no.4
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• pp.254-258
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• 2007

Five flavonoids, isorhamnetin 3-O-${\beta}$-D-galactosyl-4'-O-${\beta}$-D-glucoside (1), isorhamnetin 3,4'-di-O-${\beta}$-D-glucoside (2), isorhamnetin 3-O-${\beta}$-D-(6-O-${\alpha}$-L-rhamnosyl)glucosyl-4'-O-${\beta}$-D-glucoside (3), isorhamnetin 3-O-${\beta}$-D-(6-O-${\alpha}$-L-rhamnosyl)glucoside (4), and isorhamnetin 3-O-${\beta}$-D-(6-O-${\alpha}$-L-rhamnosyl) galactoside (5) were isolated from the stems of Opuntia humifusa (Raf.) Raf. and their structures were identified based on LC-MS and NMR data.

• Natural Product Sciences
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• v.20 no.3
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• pp.211-215
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• 2014

Opuntia humifusa, also called as Cheonnyuncho, is a cactus widely cultivated in southern regions of Korea. It has been known to have diverse biological activities, but most of the studies were performed with the MeOH extracts or solvent-partitioned fractions. Furthermore, the efforts to identify the responsible compounds for the biological activities are very limited. In this study, we tested the inhibitory effect of extracts and solvent-partitioned fractions of O. humifusa against LPS-induced nitric oxide (NO) production in Raw264.7 cells. The butanol fractions of O. humifusa efficiently inhibited the production of NO in Raw264.7 cells, but it was not due to the reduction of cell viability. Bioassay-guided isolation of butanol fractions of O. humifusa allowed the isolation of three flavonoids isorhamnetin 3-O-${\beta}$-$\small{D}$-galactosyl-4'-O-${\beta}$-$\small{D}$-glucoside (1), isorhamnetin 3,4'-di-O-${\beta}$-$\small{D}$-glucoside (2) and isorhamnetin 3-O-${\beta}$-$\small{D}$-(6-O-${\alpha}$-$\small{L}$-rhamnosyl)glucoside (3), and one lignan syringaresinol O-${\beta}$-$\small{D}$-glucopyranoside (4). Among them, isorhamnetin 3-O-${\beta}$-$\small{D}$-galactosyl-4'-O-${\beta}$-$\small{D}$-glucoside (1) and isorhamnetin 3,4'-di-O-${\beta}$-$\small{D}$-glucoside (2) exhibited the moderate inhibitory effects against LPS-induced NO production. This is the first time to report anti-inflammatory effects of these compounds.

• Animal cells and systems
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• v.7 no.4
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• pp.327-330
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• 2003

We analyzed and compared profiles of flavonols extracted from leaves and exocarps of the grape Kyoho by TLC, HPLC and UV spectrophotometry. In the exocarps, quercetin 3-O-glucoside was the main compound while isorhamnetin 3-O-glycoside (I) was present in minor amounts. In leaves, on the other hand, quercetin 3-O-glucoside and quercetin 3-O-glucoside-7-O-glucronide were the major compounds while isorhamnetin 3-O-glycoside (II) and kaempferol 3, 7-O-diglycoside were present in minor amounts.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.285-290
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• 2021

Salicornia herbacea is a type of salt marsh plant that has been used in traditional medicine to treat several diseases. Isorhamnetin-3-O-glucoside (I3G) and quercetin-3-O-glucoside (Q3G) are major flavonoids in S. herbacea that are known to exert various pharmacological activities. Therefore, our study sought to validate and optimize an HPLC/UV-based analytical method for I3G and Q3G yield quantification, as well as to determine its limit of detection, limit of quantification, linearity, precision, and accuracy. Upon testing a concentration range of 31.5-1.9 ㎍/mL the results exhibited good linearity (r² ≥0.9996 and r² ≥0.9999 for I3G and Q3G, respectively), and the procedure was deemed precise (relative standard deviation of ≤3.19 and ≤3.85%, respectively), and accurate (102.6-105.0 and 92.9-95.2%, respectively). The results showed that our proposed method could be used for rapid I3G and Q3G evaluation in S. herbacea.

• Natural Product Sciences
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• v.4 no.4
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• pp.263-267
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• 1998

From the dried flower-buds of Syzygium aromaticum Merr. et Perry (Myrtaceae), seven compounds, i.e., eugenol (1), oleanolic acid (2), kaempferol 7-O-metylether (3), 3,3',4-tri-O-methylellagic acid (4), maslinic acid (5), ${\beta}-sitosterol-3-O-glucoside$ (6), and isorhamnetin 3-O-glucoside (7) were isolated. Compound 1 showed cyclooxygenase-2 (COX-2) inhibitory activity.

• Korean Journal of Pharmacognosy
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• v.14 no.4
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• pp.137-139
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• 1983

From the leaves of Typha latifolia, L. (Thyphaceae) isorhamnetin-3-O-glucoside and isorhammetin-3-O-neohesperidoside were isolated and characterized by chemical and spectral analysis.

• Korean Journal of Pharmacognosy
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• v.24 no.1
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• pp.47-53
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• 1993

The seasonal variations of the major six flavonol glycosides(kaempferol 2,6-dirhamnosyl glucoside, quercetin 3-O-rutinoside, kaempferol 3-O-rutinoside, isorhamnetin 3-O-rutinoside, quercetin 3-O-coumaroyl glucorhamnoside and kaempferol 3-O-coumaroyl glucorhamnoside) in Ginkgo biloba leaves were investigated. The contents were determined by HPLC on reversed phase $C_{18}$ column. This result showed that the percentage of six flavonol glycosides decreased during the season from 1.57% in May to 0.39% in November. The content of each flavonol glycoside indicated a similar tendency to decrease. However, the contents of rutinosides of kaempferol, quercetin and isorhamnetin fluctuated markedly than those of coumaroyl glucorhamnosides of kaempferol and quercetin and kaempferol 2,6-dirhamnosyl glucoside.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.439-443
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• 2007

The effects of the methanol extract of the leaves of Brassica juncea and isorhamnetin $3-O-{\beta}-D-glucopyranoside$, major compound isolated from the ethyl acetate fraction of this plant on hepatic lipid peroxidation and drug-metabolizing enzymes, were evaluated in rats treated with bromobenzene. The extract and isorhamnetin $3-O-{\beta}-D-glucopyranoside$ of oral administration did not show any significant effects on activities of aminopyrine N-demethylase and aniline hydroxylase, enzymes forming toxic epoxide by bromobenzene as well as on glutathione content. However, both methanol extract and isorhamnetin $3-O-{\beta}-D-glucopyranoside$ significantly recovered the decreased activities of glutathione s-transferase and epoxide hydrolase, and also reduced the lipid peroxide level in rats treated with bromobenzene. From the results, the protections of this plant against bromobenzene-induced hepatotoxicity are thought to be via enhancing the activities of epoxide hydrolase and glutathione s-transferase, enzymes removing toxic epoxide, and reducing the lipid peroxide level.

• Korean Journal of Pharmacognosy
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• v.38 no.2 s.149
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• pp.181-186
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• 2007

Seven phenolic compounds, scopoletin (1), caffeic acid methyl ester (2), apigenin 7-O-${\alpha}$-L-rhamnosyl-(1${\rightarrow}$6)-O-${\alpha}$-D-glucoside (3), isorhamnetin 7-O-${\alpha}$-D-glucoside (4), isorhamnetin 3-O-${\alpha}$-D-glucoside (5), luteolin (6), and quercetin 3-methyl ether (7) were isolated from the methanol extract of the flowers of S. excelsus. Their structures were established by chemical and spectroscopic methods. The isolated compounds were tested for their cytotoxicity against four human cancer cell lines in vitro using a SRB method. The compounds 4 and 7 showed moderate cytotoxicity with ED$_{50}$ values ranging from 1.59 to 13.14${\mu}$g/ml.