Sterol composition in field-grown and cultured mycelia of Inonotus obliquus / 药学学报

Sterols are one of the active classes of compounds in Inonotus obliquus for their effective therapy of many diseases. In field environment, this fungus accumulates large amount of sterols. In cultured mycelia, however, this class of compounds is less accumulated. For analyzing the factors responsible for differing sterol composition, the field-grown and cultured mycelia were extracted with 80% ethanol at room temperature and total sterols were prepared using silicon gel column chromatography followed by identification using either GC-MS or spectroscopic methods. For culturing Inonotus obliquus, the seed culture was grown either in basic medium consisting of glucose (2%), yeast extract (0.5%), KH2PO4 (0.01%), MgSO4.7H20 (0.05%) and distilled water at pH 6.5, or the basic medium supplemented with serial concentrations of AgNO3. The results indicated that field-grown mycelia contained lanosterol and inotodiol (comprised 45. 47% and 25. 36% of the total sterols, respectively) and other 10 sterols (comprising the remaining 30.17%) including ergosterol biosynthetic intermediates such as 24-methylene dihydrolanosterol, 4,4-dimethylfecosterol, 4-methyl fecosterol, fecosterol and episterol. Column chromatography also led to the isolation of lanosterol, Inotodiol, trametenolic acid, foscoparianol B and a new triterpenoid foscoparianol D in field-grown mycelia. In comparison, the cultured mycelia only contained three sterols with ergosterol as the predominant one (82.20%). Lanosterol only accounted for 3.68%. Supplementing Ag+ into the culture at 0.28 micromol x L(-1) greatly enhanced content of lanosterol (accounting for 56.81%) and decreased the content of ergosterol (18.5%) together with the presence of intermediates for ergosterol biosynthesis. These results suggested that the sterol composition in mycelia of the fungus can be diversified by supplementing substances inhibiting enzymatic process towards the synthesis of ergosterol. Harsh growth conditions in field environment (i.e. temperature variation, UV irradiation etc.) can delay the synthesis of ergosterol and hereby diversify the sterol composition in the mycelia of Inonotus obliquus.

Three biflavonoids from ethanol extract of the root of Daphne genkwa / 药学学报

<p><b>AIM</b>To investigate the chemical constituents of the secondary metabolites of the roots of Daphne genkwa.</p><p><b>METHODS</b>The roots of D. genkwa were extracted with 95% ethanol at 60-70 degrees C for 7 days to obtain the crude extract. The crude extract was purified by silica gel and Sephadex LH-20 column chromatography as well as the HPLC techniques. The structures of the isolates were elucidated by combined spectroscopic methods including 1D and 2D NMR, MS, UV, IR and CD.</p><p><b>RESULTS</b>Three new biflavonoids were isolated from the ethanol extract of the roots of D. genkwa and their structures were identified as daphnodorin H-3-methyl ether (1), daphnodorin H-3"-methyl ether (2) and daphnodorin G-3"-methyl ether (3).</p><p><b>CONCLUSION</b>Compounds 1, 2 and 3 are three new biflavonoids.</p>

Isolation and identification of a new dicoumarin from the roots of Daphne genkwa / 药学学报

<p><b>AIM</b>To investigate the chemical constituents of the roots of Daphne genkwa.</p><p><b>METHODS</b>Silica gel and Sephadex LH-20 column chromatographic techniques were employed for the isolation and purification. The structure was elucidated by a combination of spectroscopic analyses.</p><p><b>RESULTS</b>A new dicoumarin named isodaphnoretin was isolated and the structure was established as 7-hydroxy-6-methoxy-4-[(2-oxo-2H-1-benzopyran-7-yl)-oxyl]-2H-1-benzopyran-2-one.</p><p><b>CONCLUSION</b>Isodaphnoretin is a new compound.</p>