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Lipophilic Extracts (lipophilic + extract)
Selected AbstractsHIGH-RESOLUTION MAGIC ANGLE SPINNING NMR ANALYSIS OF WHOLE CELLS OF CHAETOCEROS MUELLERI (BACILLARIOPHYCEAE) AND COMPARISON WITH 13C-NMR AND DISTORTIONLESS ENHANCEMENT BY POLARIZATION TRANSFER 13C-NMR ANALYSIS OF LIPOPHILIC EXTRACTS,JOURNAL OF PHYCOLOGY, Issue 3 2004Matilde S. Chauton Lipid composition in extracted samples of Chaetoceros muelleri Lemmermann was studied with 13C-NMR and distortionless enhancement by polarization transfer (DEPT) 13C-NMR, resulting in well-resolved 13C-NMR spectra with characteristic resonance signals from carboxylic, olefinic, glyceryl, methylene, and methyl groups. The application of a DEPT pulse sequence aided in the assignment of methylene and methine groups. Resonance signals were compared with literature references, and signal assignment included important unsaturated fatty acids such as eicosapentaenoic and docosahexaenoic and also phospholipids and glycerols. Results from the extracted samples were used to assign resonance signals in a high-resolution magic angle spinning (HR MAS) DEPT 13C spectrum from whole cells of C. muelleri. The NMR analysis on whole cells yielded equally good information on fatty acids and also revealed signals from carbohydrates and amino acids. Broad resonance signals and peak overlapping can be a problem in whole cell analysis, but we found that application of HR MAS gave a well-resolved spectrum. The chemical shift of metabolites in an NMR spectrum depends on the actual environment of nuclei during analysis, and some differences could therefore be expected between extracted and whole cell samples. The shift differences were small, and assignment from analysis of lipophilic extract could be used to identify peaks in the whole cell spectrum. HR MAS 13C-NMR therefore offers a possibility for broad-range metabolic profiling directly on whole cells, simultaneously detecting metabolites that are otherwise not detected in the same analytical set up and avoiding tedious extraction procedures. [source] Hypericum caprifoliatum (Guttiferae) Cham.FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 6 2006& Schltdl.: a species native to South Brazil with antidepressant-like activity Abstract In this work, previously published and unpublished results on biological activity of Hypericum caprifoliatum, a native specie to South Brazil, are presented. Lipophilic extracts obtained from this species showed an antidepressant-like activity in mice and rat forced swimming test. Results from in vivo experiments suggest an effect on the dopaminergic transmission. Besides that, in vitro experiments demonstrated that the extract and its main component (a phloroglucinol derivative) inhibit monoamine uptake in a concentration-dependent manner, more potently to dopamine, but this effect is not related to direct binding at the uptake sites. It was also observed that a 3-day treatment with lipophilic extract prevents stress-induced corticosterone rise in mice frontal cortex but not in plasma. The lipophilic and methanolic H. caprifoliatum extracts also demonstrated antinociceptive effect, which seems to be indirectly mediated by the opioid system. These results indicate that H. caprifoliatum presents a promising antidepressant-like effect in rodents which seems to be related to a mechanism different from that of other classes of antidepressants. [source] Apoptosis inducing activity of viscin, a lipophilic extract from Viscum album L.JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 1 2005K. Urech Detection of antiproliferative activity and bioactivity-guided fractionation of viscin, a lipophilic extract from Viscum album L., led to the isolation of betulinic acid, oleanolic acid and ursolic acid as active components. Viscin, betulinic acid, oleanolic acid and ursolic acid inhibited growth and induced apoptotic cell death in Molt4, K562 and U937 leukaemia cells. The growth inhibitory effect of viscin was more pronounced in Molt4 and U937 cells (IC50 (concentration that inhibited cell proliferation by 50%): 118 ± 24 and 138 ± 24 ,g mL,1) than in K562 cells (IC50: 252 ± 37 ,g mL,1). Oleanolic acid was the least effective in all cell lines (7.5,45.5% inhibition at 10 ,g mL,1) and ursolic acid the most active in Molt4 and U937 cells (81.8 and 97.8% inhibition, respectively, at 5 ,g mL,1). A dose-dependent loss of membrane phospholipid asymmetry associated with apoptosis was induced in all cell lines as shown in flow cytometry by the externalization of phosphatidylserine and morphological changes in cell size and granularity. There were differences in individual cell lines' response towards the apoptosis-inducing effect of viscin, betulinic acid, oleanolic acid and ursolic acid. The triterpenoids ,-amyrin, ,-amyrinacetate, lupeol, lupeolacetate, ,-sitosterol and stigmasterol, and the fatty acids oleic acid, linoleic acid, palmitic acid and stearic acid were also present in the lipophilic extract. [source] HIGH-RESOLUTION MAGIC ANGLE SPINNING NMR ANALYSIS OF WHOLE CELLS OF CHAETOCEROS MUELLERI (BACILLARIOPHYCEAE) AND COMPARISON WITH 13C-NMR AND DISTORTIONLESS ENHANCEMENT BY POLARIZATION TRANSFER 13C-NMR ANALYSIS OF LIPOPHILIC EXTRACTS,JOURNAL OF PHYCOLOGY, Issue 3 2004Matilde S. Chauton Lipid composition in extracted samples of Chaetoceros muelleri Lemmermann was studied with 13C-NMR and distortionless enhancement by polarization transfer (DEPT) 13C-NMR, resulting in well-resolved 13C-NMR spectra with characteristic resonance signals from carboxylic, olefinic, glyceryl, methylene, and methyl groups. The application of a DEPT pulse sequence aided in the assignment of methylene and methine groups. Resonance signals were compared with literature references, and signal assignment included important unsaturated fatty acids such as eicosapentaenoic and docosahexaenoic and also phospholipids and glycerols. Results from the extracted samples were used to assign resonance signals in a high-resolution magic angle spinning (HR MAS) DEPT 13C spectrum from whole cells of C. muelleri. The NMR analysis on whole cells yielded equally good information on fatty acids and also revealed signals from carbohydrates and amino acids. Broad resonance signals and peak overlapping can be a problem in whole cell analysis, but we found that application of HR MAS gave a well-resolved spectrum. The chemical shift of metabolites in an NMR spectrum depends on the actual environment of nuclei during analysis, and some differences could therefore be expected between extracted and whole cell samples. The shift differences were small, and assignment from analysis of lipophilic extract could be used to identify peaks in the whole cell spectrum. HR MAS 13C-NMR therefore offers a possibility for broad-range metabolic profiling directly on whole cells, simultaneously detecting metabolites that are otherwise not detected in the same analytical set up and avoiding tedious extraction procedures. [source] The chemical composition of essential oils and lipophilic extracts of Silphium integrifolium Michx. and S. trifoliatum L. leavesFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2008Rados, aw Kowalski Abstract The research presented in this paper revealed that secretory ducts in leaf stalks and main nerves of leaf blades of S. integrifolium and S. trifoliatum were of schizogenic origin and were present in varied number around vascular bundles. GC,FID and GC,MS analyses of essential oils and lipophilic extracts made from leaves collected from tested Silphium species in 1999,2001 and 2007 indicated that sesquiterpene compounds were the main constituents: germacrene D, ,- caryophyllene, caryophyllene oxide and silphiperfol-6-en-5-one. Only the oil and extracts from S. integrifolium contained significant amounts of allo -aromadendr-9-ene (8.5 ± 4.2% in oil achieved in 1999,2001, as well as 3.7 ± 0.1% and 5.7 ± 0.3 µg/ml, respectively in essential oil and extract (1:10) from 2007). Besides volatile compounds, sterols such as , -sitosterol and stigmasterol as well as triterpene alcohols (,- amyrine and , -amyrine), higher alkanes, free fatty acids and their derivatives along with vitamin E were present in tested lipophilic extracts. Copyright © 2008 John Wiley & Sons, Ltd. [source] DAF-12-dependent rescue of dauer formation in Caenorhabditis elegans by (25S)-cholestenoic acidAGING CELL, Issue 4 2006Jason M. Held Summary Population density, temperature and food availability all regulate the formation of the Caenorhabditis elegans dauer larva by modulating endocrine signaling pathways. The orphan nuclear receptor DAF-12 is pivotal for the decision to form a dauer or to undergo normal reproductive development. The DAF-12 ligand has been predicted to be a sterol that is metabolized by DAF-9, a cytochrome P450. Here we chemically characterize purified lipophilic nematode extracts and show that the ligand for DAF-12 contains a carboxyl moiety and is likely to be derived from a sterol. Using a candidate ligand approach we find that the C27 bile acid cholestenoic acid (5-cholesten-3,-ol-(25S)-carboxylic acid) promotes reproductive growth in dauer-constitutive mutants in a daf-9 - and daf-12 -dependent manner. Furthermore, we find that cholestenoic acid can act as a DAF-12 ligand by activating DAF-12 in a cell-based transcription assay. Analysis of dauer-rescuing lipophilic extracts from nematodes by gas chromatography,mass spectrometry indicates the presence of several regioisomers of cholestenoic acid that are distinct from ,5 -cholestenoic acid and are not present in extracts from daf-9 mutants. These data suggest that carboxylated sterols may be key determinants of life history. [source] Lipophilic regulator of a developmental switch in Caenorhabditis elegansAGING CELL, Issue 6 2004Matthew S. Gill In Caenorhabditis elegans, the decision to develop into a reproductive adult or arrest as a dauer larva is influenced by multiple pathways including insulin-like and transforming growth factor , (TGF,)-like signalling pathways. It has been proposed that lipophilic hormones act downstream of these pathways to regulate dauer formation. One likely target for such a hormone is DAF-12, an orphan nuclear hormone receptor that mediates these developmental decisions and also influences adult lifespan. In order to find lipophilic hormones we have generated lipophilic extracts from mass cultures of C. elegans and shown that they rescue the dauer constitutive phenotype of class 1 daf-2 insulin signalling mutants and the TGF, signalling mutant daf-7. These extracts are also able to rescue the lethal dauer phenotype of daf-9 mutants, which lack a P450 steroid hydroxylase thought to be involved in the synthesis of the DAF-12 ligand; extracts, however, have no effect on a DAF-12 ligand binding domain mutant that is predicted to be ligand insensitive. The production of this hormone appears to be DAF-9 dependent as extracts from a daf-9;daf-12 double mutant do not exhibit this activity. Preliminary fractionation of the lipophilic extracts shows that the activity is hydrophobic with some polar properties, consistent with a small lipophilic hormone. We propose that the dauer rescuing activity is a hormone synthesized by DAF-9 that acts through DAF-12. [source] Metabolomic studies of human lung carcinoma cell lines using in vitro1H NMR of whole cells and cellular extracts,NMR IN BIOMEDICINE, Issue 8 2008M. Gottschalk Abstract We report principal component analysis (PCA) of 1H NMR spectra recorded for a group of human lung carcinoma cell lines in culture and 1H NMR analysis of extracts from the same samples. The samples studied were cells of lung tumour origin with different chemotherapy drug resistance patterns. For whole cells, it was found that the statistically significant causes of spectral variation were an increase in the choline and a decrease in the methylene mobile lipid 1H resonance intensities, which correlate with our knowledge of the level of resistance displayed by the different cells. Similarly, in the 1H NMR spectra of the aqueous and lipophilic extracts, significant quantitative differences in the metabolite distributions were apparent, which are consistent with the PCA results. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||