The identification of cholesterol and other steroids in Euphorbia pulcherimma

Sekula, Bernard C.; Nes, William R.

doi:10.1016/0031-9422(80)80206-8

Cited by 25 publications

(10 citation statements)

References 13 publications

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“…The identity of F1, F2, and F3 were assigned as dihydrolanosterol, lanosterol, and cholesterol based on agreement of MS data (Supporting Information Figure S2) with literature . NMR data were in agreement with that of target compounds lanosterol, dihydrolanosterol, and cholesterol reported in the literatures .…”

Section: Resultssupporting

confidence: 77%

Separation and purification of lanosterol, dihydrolanosterol, and cholesterol from lanolin by high‐performance counter‐current chromatography dual‐mode elution method

Pei

Pan

et al. 2019

J of Separation Science

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Lanosterol is a potential drug for cataracts treatment, which can reverse the aggregation of intracrystalline proteins. The low concentration in lanolin calls for high‐performance separation methods. In this study, a counter‐current chromatography dual‐mode elution method was developed for the first time to separate and purify lanosterol from hexane extract of lanolin after saponification, in which the column was first eluted with the lower phase as mobile phase in head‐to‐tail mode, followed by the upper phase in the tail‐to‐head mode. High purity of lanosterol, dihydrolanosterol, and cholesterol can be obtained simultaneously. A solvent system composed of n‐heptane/acetonitrile/ethyl acetate (5:5:1, v/v/v) was selected and optimized via partition coefficient determination. Compounds such as 111 mg lanosterol, 84 mg dihydrolanosterol, and 183 mg cholesterol with high purity of 99.77, 95.71, and 91.43%, respectively, analyzed by high‐performance liquid chromatography were obtained within 80 min from 700 mg crude extract from 1.78 g lanolin. The method was also used to improve the purity of commercial lanosterol product from 66.97 to above 99%. Counter‐current chromatography could serve as a potential and powerful technique for commercial production of highly pure lanosterol.

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Section: Resultssupporting

confidence: 77%

Separation and purification of lanosterol, dihydrolanosterol, and cholesterol from lanolin by high‐performance counter‐current chromatography dual‐mode elution method

Pei

Pan

et al. 2019

J of Separation Science

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“…Lanosterol has been identified from several plant extracts including the latex of many Euphorbia plants (23)(24)(25)(26), but whether lanosterol is the first cyclic intermediate in phytosterol biosynthesis in these plants is controversial. Because labeled cycloartenol was converted to lanosterol in the latex, but not vice versa (27), lanosterol was not believed to be the first cyclic intermediate.…”

Section: Discussionmentioning

confidence: 99%

Dual biosynthetic pathways to phytosterol via cycloartenol and lanosterol in Arabidopsis

Ohyama

Suzuki²,

Kikuchi³

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

180

138

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The differences between the biosynthesis of sterols in higher plants and yeast/mammals are believed to originate at the cyclization step of oxidosqualene, which is cyclized to cycloartenol in higher plants and lanosterol in yeast/mammals. Recently, lanosterol synthase genes were identified from dicotyledonous plant species including Arabidopsis, suggesting that higher plants possess dual biosynthetic pathways to phytosterols via lanosterol, and through cycloartenol. To identify the biosynthetic pathway to phytosterol via lanosterol, and to reveal the contributions to phytosterol biosynthesis via each cycloartenol and lanosterol, we performed feeding experiments by using [6-13 C 2 H3]mevalonate with Arabidopsis seedlings. Applying 13 C-{ 1 H}{ 2 H} nuclear magnetic resonance (NMR) techniques, the elucidation of deuterium on C-19 behavior of phytosterol provided evidence that small amounts of phytosterol were biosynthesized via lanosterol. The levels of phytosterol increased on overexpression of LAS1, and phytosterols derived from lanosterol were not observed in a LAS1-knockout plant. This is direct evidence to indicate that the biosynthetic pathway for phytosterol via lanosterol exists in plant cells. We designate the biosynthetic pathway to phytosterols via lanosterol ''the lanosterol pathway.'' LAS1 expression is reported to be induced by the application of jasmonate and is thought to have evolved from an ancestral cycloartenol synthase to a triterpenoid synthase, such as ␤-amyrin synthase and lupeol synthase. Considering this background, the lanosterol pathway may contribute to the biosynthesis of not only phytosterols, but also steroids as secondary metabolites. metabolic diversity ͉ mevalonate ͉ sterol ͉ tracer experiment ͉ triterpene

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“…2, with a dealkylation of24-ethyl sterols postulated to occur as has been observed for insects (21). A branched pathway in which lanosterol may be bypassed metabolically has also been described in plants (22 …”

mentioning

confidence: 96%

Cycloartenol-derived sterol biosynthesis in the Peronosporales

Warner¹,

Eierman²,

Sovocool³

et al. 1982

Proc. Natl. Acad. Sci. U.S.A.

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Selected species of the order Peronosporales, which are unable to epoxidize squalene and thus synthesize sterols, are able to metabolize exogenous cycloartenol to lanosterol and in some organisms to fucosterol, ergosterol, and cholesterol. Lanosterol was less effectively utilized but some ergosterol and cholesterol were yielded. Fucosterol was very efficiently metabolized by most species to ergosterol, A7-ergostenol, A5-ergostenol, cholestanol, and cholesterol. Several unknown sterols were observed in most trials. These data suggest a vestigial sterol synthetic pathway derived from cycloartenol, followed by possible isomerization to lanosterol and then to other sterols.It has been established that species of Pythium and Phytophthora require exogenous sterols for sexual reproduction (1, 2). These organisms are unable to synthesize sterols because of a missing squalene epoxidase (3). Metabolism of exogenous sterols has been observed in Phytophthora cactorum by Langeake (4), who reported possible conversion of lanosterol to cholesterol. Nes and Patterson (5) reported that Phyt. cactorum was unable to transform cycloartenol or lanosterol to other sterols. Conversion ofA7 and A5'7 sterols to A5 sterols has been reported by Elliott and Knights (6) in Phyt. cactorum, which additionally synthesizes cholesteryl esters, cholesteryl glucosides, and acyl sterol glycosides (7,8). Other than the above, sterol conversions in Phytophthora or Pythium have, in general, not been demonstrated in detail.Lagenidium giganteum is another Oomycete, but of the Lagenidiales, that requires exogenous sterols to produce zoospores (9). Warner and Domnas (10) have shown that this organism converts cycloartenol, but not lanosterol, to cholesterol. Because Lagenidium species are able to metabolize cycloartenol, it was ofconsiderable interest to observe ifthis compound could be metabolized by selected species ofthe Peronosporales. This article reports our observations. Inoculation and growth were as described (10) (10) and the unsaponifiable lipid fraction was obtained. The sterols were separated on HPLC with a Waters instrument by using a 10-,um C18 column (4.6 x 250 mm). Fractions were eluted with methanol/H20 (96:4) at 2 ml/min flow with UV detection at 210 nm. MATERIALS AND METHODS MicroorganismsSterols were identified by gas/liquid chromatography on 3% SE-30 and 1% QF-1 with a Packard 417 FID chromatograph as described (10). Confirmation ofidentification was obtained with gas chromatography/electron impact mass spectroscopy (70 eV) with a Finnegan 4023 instrument. A 15-m flexible fused silica capillary coated with OV-101 was programmed from 160 to 2600C at 10°C/min with an initial hold of 3 min. RESULTSNo sterols were found in control organisms to the limit of detection (0.0001%). Uninoculated control cultures yielded a stoichiometric recovery of the administered sterols.Sterols Isolated After Administration ofCycloartenol. Table 1 illustrates the substances identified in the organisms examined. Clear evidence was obtained for the ...

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The identification of cholesterol and other steroids in Euphorbia pulcherimma

Cited by 25 publications

References 13 publications

Separation and purification of lanosterol, dihydrolanosterol, and cholesterol from lanolin by high‐performance counter‐current chromatography dual‐mode elution method

Separation and purification of lanosterol, dihydrolanosterol, and cholesterol from lanolin by high‐performance counter‐current chromatography dual‐mode elution method

Dual biosynthetic pathways to phytosterol via cycloartenol and lanosterol in Arabidopsis

Cycloartenol-derived sterol biosynthesis in the Peronosporales

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