• Korean Journal of Pharmacognosy
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• v.31 no.4
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• pp.430-433
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• 2000

Five compounds have been isolated from the stem of Caesalpinia japonica. On the basis of spectral evidences, the structures of these compounds were identified as 4',7-dihydroxyflavone, 3,4',7-trihydroxyflavone, cathechin, 3',4',7-trihydroxyflavone and 2',3,4',5,6,7-hexahydroxyflavone.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3169-3174
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• 2014

Numerous studies have examined the role of flavonoids in modulating inflammatory responses in vitro. In this study, we found a novel flavonoid, 3,6,3'-trihydroxyflavone (1), with anti-inflammatory effects. Anti-inflammatory activity and mechanism of action were examined in mouse macrophages stimulated with lipopolysaccharide (LPS). Our results showed that the anti-inflammatory effects of 1 are mediated via p38 mitogen-activated protein kinase (p38 MAPK), Jun-N terminal kinase (JNK), and the extracellular-signal-regulated kinase (ERK) pathway in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Binding studies revealed that 1 had a high binding affinity to JNK1 ($1.568{\times}10^8M^{-1}$) and that the 3- and 6-hydroxyl groups of the C-ring and A-ring of 1 participated in hydrogen bonding interactions with the side chains of Asn114 and Lys55, respectively. The oxygen at the 3' position of the B-ring formed a hydrogen bond with side chain of Met111. Therefore, 1 could be a potential inhibitor of JNKs, with potent anti-inflammatory activity.

• Natural Product Sciences
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• v.16 no.4
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• pp.217-222
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• 2010

A phytochemical investigation of the ethanolic extract of Erythrina caffra flowers from an Egyptian origin yielded three C-flavonoidal glycosides; 5,7,4'-trihydroxyflavone-8-C-$\beta$-D-glucopyranoside (vitexin) (1), 5,7,4'-trihydroxyflavone-6-C-$\beta$-D-glucopyranosyl-(1 $\rightarrow$ 2)-$\beta$-D-glucopyranoside (isovitexin-2"-$\beta$-D-glucopyranoside) (2), 5, 7, 4'-trihydroxyflavone-6, 8-di-C-$\beta$-D-glucopyranoside (vicenin-2) (3) and one O-flavonoidal glycoside; kaempferol-3-O-$\beta$-D.glucopyranosyl) (1 $\rightarrow$ 2)-$\beta$-D-glucopyranoside (4). The structures of the isolated compounds (1 - 4) were elucidated using different spectral techniques (UV, 1D and 2D NMR and HRESIMS). This is the first report for the isolation of flavonoidal glycosides from Erythrina caffra. The antibacterial, antifungal, antimalarial, and antileishmanial activities of the isolates were evaluated. In addition, the cytotoxic activity of the ethanolic extract and the main fractions were tested using brine shrimp bioassay.

• Archives of Pharmacal Research
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• v.26 no.6
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• pp.458-462
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• 2003

The antioxidant activity of the stem bark from Albizzia julibrissin was evaluated for its potential to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, to inhibit the generation of the hydroxyl radical ($\cdot OH$), total reactive oxygen species (ROS) and to scavenge authentic peroxynitrites ($ONOO^{-}$). The methanol extract of A. julibrissin exhibited strong antioxidant activity in the tested model systems. Therefore, it was further fractionated using several solvents. The antioxidant activity of the individual fractions were in the order of ethyl acetate (EtOAc) ＞ n-butanol (n-BuOH) ＞ dichloromethane ($CH_2 CI-2$) ＞ and water ($H_2O$). The ethyl acetate soluble fraction, which exhibited strong antioxidant activity, was further purified by repeated silicagel, Sephadex LH-20 and RP-18 gel column chromatography. Sulfuretin (1) and 3 ,4 ,7-trihydroxyflavone (2) were isolated as the active principles. Compounds 1 and 2 exhibited good activity in all tested model systems. Compound 1 exhibited five times more inhibitory activity on the total ROS than Trolox. Compound 2 showed six times stronger DPPH radical scavenging activity than L-ascorbic acid. These results show the possible antioxidant activity of the A. julibrissin crude extract and its major constituents.

• YAKHAK HOEJI
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• v.32 no.2
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• pp.125-128
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• 1988

Geranylation of some synthetic and natural flavones have yielded cytotoxic products against L1210 coll; 5,2´-dihydroxy-6,7,8-trimethoxy-6´-geranyloxyflavone 4$(8.5{\mu}g/ml)$, 5,6-dihydroxy-7-gerenyloxyflavone 9$(2.3{\mu}g/ml)$. 2 has showed the same range of cytotoxicity as the starting material, 5,2´-dihydroxy-6,7,8-trimethoxy-6´-benzyloxyflavone$(17.0{\mu}g/ml)$. The cytotoxicity of 4 was lower than its starting substance, 5,2´,6´-trihydroxy-6,7,8-trimethoxyflavone $(4.5{\mu}g/ml)$. On geranylating 5,6,7-trihydroxyflavone(baicalein, $15.0{\mu}g/ml$) the cytotoxic activity has been strongly potentiated($2.3{\mu}g/ml$ of 9). The presence of at least a free hydroxy group in B-ring of Skullkapflavone II-type flavones. was essential for a high activity. A larger RD-group than methoxy in the B-ring has weakened the activity. The cytotoxicities of baicalein series could not be correlated to their structures.

• Journal of Life Science
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• v.19 no.8
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• pp.1009-1015
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• 2009

The beneficial use of sedatives is often required for medically ill patients. This study examined the effect of plant flavonoids and diazepam peripheral-type benzodiazepine receptor (PBR) activation and glucose utilization in breast cancer cells, along with their interactions. In estrogen receptor negative MDA-MB-231 cells, the anti-proliferative activity of fisetin (3,7,3',4'-tetrahydroxyflavone) and diazepam was more prominent than in estrogen receptor positive MCF-7 cells. Unlike PBR ligands, treatment with $10^{-6}$ M concentration of diazepam for 3 days exhibited anti-proliferative effects, while similar to apigenin (4',5,7-Trihydroxyflavone) and fisetin, diazepam hardly affected the PBR mRNA expression by MDA-MB-231 cells. Treatment with $10^{-6}$ M concentration of flavonoids and diazepam for 3 days inhibited the glucose utilization of MDA-MB-231 cells. Treatment with $10^{-6}$ M concentration of flavonoids and diazepam for 6 days showed increased cytotoxicity and reduced the PBR mRNA expression of the MDA-MB-231 cells. Apigenin enhanced diazepam-induced anti-proliferative effects on the MDA-MB-231 cells as well. All together, this study showed the in vitro anti-proliferative activity of flavonoids and diazepam on MDA-MB-231 breast cancer cells, plus additive enhancements. In conclusion, this study provides experimental basis for advanced trials in the future.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.578-586
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• 2008

Phytochemicals study from the leaves of soybean [Glycine max (L.) Merr.], one of Korean edible plant materials were investigated through various chromatographic procedures. The methanolic leaves extracts of soybean yielded 16 phytochemicals, including 5 isoflavones 1-5, 3 flavones 6-8, 1 flavonol 9, 2 pterocarpans 10 and 11, 2 phenolic compounds 12 and 13, 2 phytosterols 14 and 15, and 1 sugar alcohol 16. The structures were fully characterized by analysis of physical and spectral data and were defined clearly as 4,5,7-trihydroxyisoflavone (1), 4,5,7-trihydroxyisoflavone-7-O-$\beta$-D-glucopyranoside (2), 4,7-dihydroxy-6-methoxyisoflavone (3), 4,7-dihydroxyisoflavone (4), 4,7-dihydroxyisoflavone-7-O-$\beta$-D-glucopyranoside (5), 5,7,4'-trihydroxyflavone (6), 3',4',5,7-tetrahydroxyflavone (7), 3',4',5-trihydroxyflavone-7-O-$\beta$-D-glucopyranoside (8), 3,4',5,7-tetrahydroxyflavonol (9), coumestrol (10), glyceofuran (11), 4-hydroxybenzoic acid (12), methyl-4-hydroxybenzoate (13), soyasapogenol B (14), stigmasterol (15), and D-mannitol (16), respectively. Among them, phytochemicals 7-16 were reported for the first time on the isolation and confirmation from the leaves of this species. These results suggest that the leaves extracts of soybean may possess possible health related benefits to human due to the isolated phytochemicals 1-16 which have been well known potential effects on various chronic diseases.

• Archives of Pharmacal Research
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• v.18 no.6
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• pp.415-422
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• 1995

Twenty-four flavones were synthesized with various hydroxyl and/or methoxyl groups on A and B rings. Their antimutagenic properties were evaluated against ben:w(a)pyrene (BaP) and a pool of mutagenic urine concentrate (U) using a modified liquid incubation method of Ames test. The tester strain was Salmonella typhimurium TA98+S9 Mix. The antimutagenic activities were calculated by non linear regression analysis and the doses of flavones (in nmoles) required for a 50% reduction of induced revertants with BaP and U were defined as the inhibition doses (TEX>$ID_{508}{\;}and{\;}ID_{508}$ respectively). Seventeen flavones possessed significant antimutagenic activity against BaP. $ID_{508}$ ranged from 15.1 nmoles (F22) to 1000.6 nmoles (F13). Eighteen f1avones showed significant antimutagenic activity against U. $ID_{50U}$ ranged from 23.5 nmoles (F22) to 354.6 nmoles (F3). The 2',3',4'-trihydroxyflavone (F22, $ID_{508}=15.1$ nmoles, $ID_{50U}=23.5$ nmoles) and the 2',3',4',7-tetrahydroxyflavone (F20, $ID_{508}=37.8$ nmoles; $ID_{50U}=62.3$ nmoles) had antimutagenic activities similar to those of chlorophyllin ($ID_{508}=19.6$ nmoles and $ID_{50U}=44.2$ nmoles) and were evaluated against B(alP 7,8-dihydrodiol-9,10-epoxide. Against this last mutagen, the flavones which included three OH in B ring showed the highest activity and this property seemed independent of the substituent groups on A ring.

• Biomolecules & Therapeutics
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• v.25 no.6
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• pp.641-647
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• 2017

Galangin (3,5,7-trihydroxyflavone) is a polyphenolic compound abundant in honey and medicinal herbs, such as Alpinia officinarum. In this study, we investigated the anti-inflammatory effects of galangin under in vitro and in vivo neuroinflammatory conditions caused by polyinosinic-polycytidylic acid (poly(I:C)), a viral mimic dsRNA analog. Galangin suppressed the production of nitric oxide, reactive oxygen species, and pro-inflammatory cytokines in poly(I:C)-stimulated BV2 microglia. On the other hand, galangin enhanced anti-inflammatory interleukin (IL)-10 production. Galangin also suppressed the expression of pro-inflammatory markers in poly(I:C)-injected mouse brains. Further mechanistic studies showed that galangin inhibited poly(I:C)-induced nuclear factor (NF)-${\kappa}B$ activity and phosphorylation of Akt without affecting MAP kinases. Interestingly, galangin increased the expression and transcriptional activity of peroxisome proliferator-activated receptor (PPAR)-${\gamma}$, known to play an anti-inflammatory role. To investigate whether PPAR-${\gamma}$ is involved in the anti-inflammatory function of galangin, BV2 cells were pre-treated with PPAR-${\gamma}$ antagonist before treatment of galangin. We found that PPAR-${\gamma}$ antagonist significantly blocked galangin-mediated upregulation of IL-10 and attenuated the inhibition of tumor necrosis factor (TNF)-${\alpha}$ and IL-6 in poly(I:C)-stimulated microglia. In conclusion, our data suggest that PI3K/Akt, NF-${\kappa}B$, and PPAR-${\gamma}$ play a pivotal role in mediating the anti-inflammatory effects of galangin in poly(I:C)-stimulated microglia.

• Journal of Life Science
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• v.20 no.10
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• pp.1519-1524
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• 2010

Apigenin (4', 5, 7-trihydroxyflavone), a common dietary flavonoid abundantly present in fruits and vegetables, has shown remarkable anti-proliferative effects against various malignant cell lines. To observe the anti-proliferative effects, oral cavity cancer cell lines, $6{\times}10^3$ cells/well (96 well plate) of KB oral cavity tumor cells were plated and 24 hr later treated with apigenin for one day, after which MTT assay was performed. Apigenin induced cell death in a dose-dependent manner after incubation. Cell viability was significantly decreased in the group treated with 100 ${\mu}M$ apigenin for 24 hr (p<0.05) compared to the control group. To assess apoptosis, the nuclei of KB cells were stained with DAPI. The presence of chromatin condensation in the apigenin treated cells was detected on a fluorescent microscope (${\times}200$). We investigated the in vivo growth inhibitory effects of apigenin on oral cavity cancer KB tumor xenograft subcutaneously implanted in male nude mice. Apigenin was administered to mice by gavage at doses of 25 and 50 mg/kg/day in 0.2ml of PBS. Tumor volume was significantly decreased in 25 and 50 mg/kg apigenin-administration groups compared to the control group. For apoptosis analysis, TUNEL staining was performed. A significant increase in TUNEL positive cells was found in the 25 mg/kg apigenin administration group compared to the non- apigenin administration group. Histopathological changes were not observed. These results indicate that apigenin inhibits oral cavity cancer cell growth through the induction of apoptosis.