• Journal of Microbiology and Biotechnology
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• v.22 no.5
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• pp.622-627
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• 2012

Mast cells and basophils are important effector cells in immunoglobulin-E (IgE)-mediated allergic reactions. Using the human basophilic KU812F cells, we assessed the inhibitory effects of 6-methoxyluteolin, isolated from Chrysanthemum zawadskii, in the $Fc{\varepsilon}RI$-mediated allergic reaction. We determined that 6-methoxyluteolin inhibited anti-$Fc{\varepsilon}RI$ ${\alpha}$ chain antibody (CRA-1)-induced histamine release, as well as elevation of intracellular calcium concentration $[Ca^{2+}]_i$ in a dose-dependent manner. Moreover, the inhibitory effects of 6-methoxyluteolin on the cell surface expression and the mRNA level of the $Fc{\varepsilon}RI$ ${\alpha}$ chain were determined by flow cytometric analysis and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Therefore, these results show that 6-methoxyluteolin is a potent inhibitor of histamine release and calcium influx via down-regulation of the $Fc{\varepsilon}RI$ ${\alpha}$ chain.

• Natural Product Sciences
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• v.13 no.3
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• pp.190-194
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• 2007

Two new flavonoid compounds, 8,8'-bisbaicalein 1 and baicalein-7-O-caffeate 2 along with six known flavonoids, baicalein, chrysin, scutellarein, 6-hydroxyluteolin, 6-methoxyluteolin and baicalein-7-Oglucoside and ${\beta}-sitosterol$ have been isolated from the stem-bark of Oroxylum indicum (Bignoniaceae) and identified on the basis of spectroscopic and chemical studies. 6-Hydroxyluteolin and 6-methoxyluteolin are reported for the first time from this plant.