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1.
A validated method for the simultaneous determination of prominent volatile cleavage products (CPs) of β-carotene in cell culture media has been developed. Target CPs comprised β-ionone (β-IO), cyclocitral (CC), dihydroactinidiolide (DHA), and 1,1,6-trimethyltetraline (TMT). CPs were extracted by solid-phase extraction applying a phenyl adsorbent, eluted with 10% (v/v) tetrahydrofuran in n-hexane, and identified and quantified by gas chromatography-mass spectrometry with electron impact ionization. Method validation addressed linearity confirmation over two application ranges and homoscedasticity testing. Recoveries from culture media were between 71.7% and 95.7% at 1.0 μg/ml. Precision of recoveries determined in intra-day (N = 5) and inter-day (N = 15) assays were <2.0% and <4.8%, respectively. Limit of detection and limit of quantification of the analysis method were <18.0 and <53.0 ng/ml for β-IO, CC, and TMT, whereas 156 and 474 ng/ml were determined for DHA, respectively. Although extractions of blank matrix proved the absence of interfering peaks, statistical comparison between slopes determined for instrumental and total method linearity revealed significant differences. The method was successfully applied in selecting an appropriate solvent for the fortification of culture media with volatile CPs, including the determination of their availability over the incubation period. For the first time, quantification of volatile CPs in treatment solutions and culture media for primary cells becomes accessible by this validated method.  相似文献   

2.
A new method of capillary zone electrophoresis (CZE) was established by simultaneous assay of four eremophilenolides, 3β-acetoxy-9β-angeloyloxy-1β,10β-epoxy-8α-hydroxyeremophil-7(11)-en-8β (12)-olide (1), 3β-senecioyloxy -1β,10β-epoxy-8α-hydroxyeremophil-7(11)-en-8β (12)-olide (2), 6α-hydroxy-1β,10β-epoxy-8α-hydroxyeremophil-7(11)-en-8β (12)-olide (3) and 3β-acetoxy- 6β-angeloyloxy-1β,10β-epoxy-8α-hydroxyeremophil-7(11)-en-8β (12)-olide (4) in the Chinese herbal extract from Ligulariopsis shichuana. The optimum buffer system was 20 mM borate buffer (pH 10.00). Voltage was 25 kV and detection at 214 nm. Regression equations revealed linear relationships (correlation coefficients 0.9986, 0.9990, 0.9992 and 0.9995) between the peak area of each compound and its concentration. The relative standard deviations of migration times and peak areas were <1.35 and 3.94% within 1 day, respectively. The effects of several CE parameters on the resolution were studied systematically. The contents of four eremophilenolides in Ligulariopsis shichuana were successfully determined with satisfactory repeatability and recovery.  相似文献   

3.
A new furostane-type steroidal glycoside and derivative of tigogenin (1) was isolated from aqueous wastes from production of the cardiac drug acetyldigitoxin from leaves of Digitalis ciliata Trautv. (Scrophulariaceae) and characterized. The structure of the glycoside was established using physical constants, chemical transformations, and spectral data as 3-O-β-D-glucopyranosyl-(1→3) [β-D-fucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-β-D-galactopyranosyl-(25R)-5α-furostan-3β,22α,26-triol-26-O-β-D-glucopyranoside.  相似文献   

4.
In this paper a new method for the functionalization of porous membranes with β-CD is reported. Porous polypropylene (PP) hollow fibres have been impregnated with a mixture composed by a partially cross-linked polydimethylsiloxane (PDMS) and β-cyclodextrin (β-CD). The prepolymerization of the PDMS components was necessary to avoid their inclusion in the β-CD cavity. The firm heterogenization of the β-CD was obtained by in situ cross-linking of the PDMS/β-CD network in the porous membranes. The presence of the PDMS/β-CD network in the membranes was confirmed by FT-IR-ATR (on the outer and inner surfaces) and EDX analyses (on the cross-section).The effect of the impregnation times on membrane morphology, loading and porosity has been investigated. The binding capacity of the heterogenized β-CDs has been tested using the phenolphthalein as guest molecule.  相似文献   

5.
It was shown that carrying out the reaction of cholesterol photosensitized oxidation in the presence of porphyrins immobilized on the hydrolyzed copolymer of tetrafluorethylene and H+ form of perfluoro-3,6-dioxo-5-methyl-6-sulfonylfluorideoctene-1 leads to the formation of not previously described new products: 6β-phormyl-B-norcholestan-3β,5β-diol, 6β-chlorocholestan-3β,5α-diol, cholestan-3β,5α,6β-triol, and 5α-chlorocholestan-3β,6β-diol.  相似文献   

6.
A new steroid glycoside was isolated from leaves of Digitalis ciliata (Scrophulariaceae) by fractionation of the total extracted substances. Its structure was determined as (25R)-5α-spirostan-3β-ol 3-O-β-D-glucopyranosyl-(1→3)[β-D-fucopyranosyl-(1→2)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside based on chemical transformations, physical constants, and spectral data. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 135–137, March–April, 2007.  相似文献   

7.
From a methanolic extract of the skins of the bulbs ofAllium giganteum Rgl, a new steroid glycoside has been isolated — aginoside, which is (25R)-5α-spirostan-2α, 3β, 6β-triol 3-0-{[0-β-D-xylopyranosyl-(1→3)-]-[0-β-D-glucopyranosyl-(1→2)]-0-β-D-glucopyranosyl-(1→4)-0-β-D-galactopyranoside}.  相似文献   

8.
Summary A new chiral derivatizing agent (CDA), (1S,2S)-1,3-diacetoxy-1-(4-nitrophenyl)-2-propylisothiocyanate, (S,S)-DANI, was applied to the separation of the enantiomers of unusual amino acids containing two chiral centers. Different β-methyl-α-amino acids (β-MePhe, β-MeTyr and β-MeTrp) and β-amino acids with cycloalkane skeletons (2-aminocyclopentanecarboxylic acid and 2-aminocyclohexanecarboxylic acid) were derivatized and the thiourea derivatives produced were separated by reversed-phase high-performance liquid chromatography. The applicability of this new CDA in the separation of unusual amino acids is demonstrated. The four stereoisomers of the investigated amino acids (except β-MePhe) could be separated in one chromatographic run. Presented at Balaton Symposium on High Performance Separation Methods, Siófok, Hungary, September 1–3, 1999  相似文献   

9.
The structures of five furostanol glycosides (1–5), of which the 26-O-β-D-glucopyranosyl-(25S),5α-furost20(22)-en-12-one-2α,3β,26-triol-3-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (1) was new, from the leaves of Tribulus terrestris L. were established using chemical and NMR spectroscopic methods.  相似文献   

10.
A new minor asterosaponin (20S)-6-O-{β-d-fucopyranosyl-(1→2)-[β-d-fucopyranosyl-(1→4)-β-d-quinovopyranosyl-(1→2)]-β-d-quinovopyranosyl-(1→3)-β-d-quinovopyranosyl}-3β,6α,20-trihydroxycholest-9(11)-en-23-one 3-sulfate (archasteroside C) was isolated from the starfish Archaster typicus collected in shallow coastal waters of Vietnam. The structure of archasteroside C was determined by 2D NMR spectroscopy and electrospray ionization (ESI) tandem mass spectrometry.  相似文献   

11.
A new triterpene glycoside of the cycloartane series that was called askendoside H was isolated from roots of Astragalus taschkendicus Bunge (Leguminosae). Its structure was elucidated based on chemical transformations and spectral data. Askendoside H was a bisdesmoside of cycloorbigenin C, 23R,24Rcycloartan-3β,6α,16β,23,24,25-hexaol 3-O-[(α-L-arabinopyranosyl)(1 → 2)-β-D-xylopyranoside] 23-O-βD-glucopyranoside.  相似文献   

12.
The new cycloartane glycoside cycloorbicoside D, which has the structure 23ξ,24ξ-cycloartan-3β6α,16β,23,24,25-hexaol 3-O-β-D-xylopyranoside, was isolated from the aerial part of Astragalus orbiculatus Ledeb. (Leguminosae). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 345–346, July–August, 2005.  相似文献   

13.
Chemical investigation of the aerial part of Peganum nigellastrum furnished a new flavone glycoside, and the structure was established by NMR, MS, and DEPT, HSQC, and HMBC as diosmetin 7-O-β-Dglucopyranosyl(1→2)-β-D-glucopyranosyl(1→2)-[α-L-rhamnopyranosyl(1→6)]-β-D-glucopyranoside.  相似文献   

14.
Two new polyhydroxysteroids and five new glycosides were isolated from the starfishCeramaster patagonicus and their structures were elucidated: 5α-cholestane-3β,6α,15β,16β,26-pentol, (22E)-5α-cholest-22-ene-3β,6α,8,15α,24-pentol, (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β,4β, 6α,8,15β,16β,28-heptol (ceramasteroside C1), (22E)-28-O-[O-(2,4-di-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β, 6α,8,15β,16β,28-hexol (ceramasteroside C2), (22E)-28-O-[O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-hydroxymethyl-5α-cholest-22-ene-3β,6α,8,15β,16β 28-hexol (eramasteroside C3), (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-galactofuranosyl]-24-methyl-5α-cholest-22-ene-3β,4β,6α,8, 15β, 26-hexol (ceramasteroside C4), and (22E)-28-O-[O-(2-O-methyl-β-d-xylopyranosyl)-(1→2)-β-d-xylopyranosyl]-5α-cholest-22-ene-3β,6α,8,15β,24-pentol (ceramasteroside C5)). Three known polyhydroxysteroids (24-methylene-5α-cholestane-3β,6α,8,15β,16β,26-hexol, 5α-cholestane-3β,6α,8,15β,16β,26-hexol, and 5α-cholestane-3β,6β,15α,16β,26-pentol) were also isolated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 190–195, January, 1997.  相似文献   

15.
A new furostanol glycoside, named ophiopogonin J (1), was isolated from the fibrous root of Ophiopogon japonicas. The structure of the compound was established as (25R)-26-[(O-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl)]-20α -hydroxyfurost-5, 22-diene-3-O-α-L-rhamnopyranosyl-(1 → 2)-[β-D-xylopyranosyl(1 → 4)]-β-D-glucopyranoside on the basis of spectroscopic methods, including HR-ESI-MS and 1D and 2D NMR experiments.  相似文献   

16.
A new polyhydroxysteroid was isolated from the starfishLuidiaster dawsoni; the structure of the product was established as (24S,25R)-24-methylcholestane-3β, 5α, 6β, 15α, 16β, 26-hexaol. A mixture of methyl-α- and β-d-glucopyranosides was also isolated from the extract of this starfish. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2088–2090, October, 1998.  相似文献   

17.
Two new triterpene glycosides of the cycloartane series, which have been called cyclostipulosides A and B, have been isolated in the individual form from the roots ofTragacantha stipulosa Boviss. Their structures have been established by physicochemical methods. Cyclostipuloside A is 24R-cycloartane-3β,6α,16β,24,25-pentaol 16-O-β-D-glucopyranoside 3-O-β-D-xylopyranoside, and cyclostipuloside B is 24R-cycloartane-3β,6α,16β,24,25-pentaol 6-O-α-L-arabinopyranoside 16-O-β-D-glucopyranoside 3-O-β-D-xylopyranoside. By the acid hydrolysis of cyclostipulosides A and B we have obtained the new glycoside 24R-cycloartane-3β,6α,16β,24,25-pentaol 16-O-β-D-glucopyranoside. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (371) 120 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 670–674, September–October, 1998.  相似文献   

18.
In addition to the know steroid sapogenin (25S)-ruscogenin (I), three new glycosides have been isolated from the leaves ofNolina microcarpa S. Wats. (family Dracaenacea), and the following structures are suggested for them: (25S)-spirost-5-ene-1β,3β-diol 1-O-β-D-fucopyranoside (nolinospiroside C, II), (25S)-furost-5-ene-1β,3β,22α,26-tetraol 1-O-β-D-fucopyranoside (nolinofuroside A, III), and (25S)-furost-5-ene-1β, 3β, 22α, 26-tetraol 1-O-β-D-fucopyranoside 26-O-β-D-glucopyranoside (nolinofuroside C, V). M. V. Frunze Simferopol' State University. Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 672–678, September–October, 1991.  相似文献   

19.
We have isolated from Crimean ivy berries in addition previously known triterpene glycosides — 3-O-α-L-arabinopyranosyl-28-O-[O-α-L-rhamnopyranosyl-(1 → 4)-O-β-D-glycopyranosyl-(1 → 6)-β-D-glucopyranosyl]hederagenin, 3-O-[O-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl]-28-O-[O-α-L-rhamnopyranosyl-(1 → 4)-O-β-D-glucopyranosyl-(1 → 6)-β-D-glycopyranosyl]hederagenin, the new triterpene glycosides hederoside H2-3-O-[O-β-D-glycopyranosyl-(1 → 2)-β-D-glycopyranosyl-(1 → 2)-β-D-glucopyranosyl]-28-O-[O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]oleanolic acid- and hederoside I-3-O-[O-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl]-28-O-[O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]hederagenin. Details of their13C NMR spectra are given. M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 779–783, November–December, 1990.  相似文献   

20.
Thalicoside D — a new triterpene glycoside isolated fromThalictrum minus L. (Ranunculaceae) — has the structure of oleanolic acid 3-O-[O-α-L-rhamnopyranosyl-(1→2)-O-β-D-glucopyranosyl-(1→4)-α-L-arabinopyranoside 28-O-[O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside]. This structure was established by the use of the results of acid and alkaline hydrolyses, SIMS spectra, and one- and two-dimensional NMR spectroscopy. Deceased.  相似文献   

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