• Natural Product Sciences
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• v.5 no.2
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• pp.93-96
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• 1999

A new ergosteryl myristate (1) and ergosterol (2) have been isolated from the organic extract of the mycelium of unidentified marine algicolous fungus, isolate MF001. The structure of a new compound was assigned on the basis of comprehensive spectroscopic analyses and chemical synthesis.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1339-1344
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• 2013

We have synthesized several glycosyl ergosterols and 5,6-dihydroergosterols (DHE) and examined their effects on production of nitric oxide (NO) and iNOS protein expression in LPS-treated RAW264.7 macrophage cells. Our results showed that DHE derivatives inhibited production of NO and iNOS protein expression more strongly than ergosterol derivative. Especially, DHE-Glc exhibited most potent inhibitory activity without cytotoxicity up to the concentration of $100{\mu}M$.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.693-697
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• 2004

YH-1715R, (2R,3R)-2-(2,4-difluorophenyl)-3-(3-methoxy-1,2,4-isothiazol-3-yl-thio)-1-( 1H-1,2,4-triazol-l-yl)-2-butanol, a new triazole derivative obtained by the structural modification of fluconazole, was found to exhibit potent anti-Candida activity against a wide variety of Candida albicans (C. albicans) (MIC: 0.4-12.5 mg/l). To investigate the mode of action of YH-1715R, its effect on ergosterol biosynthesis in cell-free extracts and whole cells of C. albicans was examined. The inhibitory activity of YH-1715R was approximately ten-fold higher than that of fluconazole. To determine the primary action mechanism of YH-1715R, its inhibitory activity against lanosterol $14\alpha$-demethylase (14$\alpha$-DM), a major target for azole, was measured using gas-liquid chromatography. YH-1715R and fluconazole were found to inhibit 14a-DM with an $IC_{50}$ of 0.015 $\mu$M and 0.01$8\mu$M, respectively, plus the mode of inhibition of YH-1715R and fluconozole was noncompetitive with a $K_i$ of 0.0533$\mu$M and 0.0975$\mu$M.

• YAKHAK HOEJI
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• v.50 no.6
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• pp.367-371
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• 2006

Phellinus pini (Hymenocaetaceae) has been used for the immunomodulating activity hypolipidemic effect, gastric cancer non-insulin dependant diabetes, diarrhea, and menstrual irregularity. From the screening of each fraction for the inhibitory activity of NO production in lipopolysaccaride (LPS) activated RAW 264.7 cells, methanol extract of Phellinus pini and hexane soluble fraction exhibited inhibition of NO production compared with LPS control without toxicity. The hexane soluble fraction showed dose dependent inhibition of NO production. According to activity guided fractionation, the active hexane fr. was repeatedly chromatographed over silica gel, ergosta-4,6,8(14),22- tetraen-3-one was isolated. The compound inhibited NOS activation (IC$_{50}$ = 29.7 uM) and NO production of activated macrophage at 30 uM.