Identification Of Sterols Research Articles

Dynamic Variation of Amino Acid Contents and Identification of Sterols in Xinyang Mao Jian Green Tea.

As important biomolecules in Camellia sinensis L., amino acids (AAs) are considered to contribute to the overall green tea sensory quality and undergo dynamic changes during growth. However, limited by analytical capacity, detailed AAs composition in different growth stages remains unclear. To address this question, we analyzed the dynamic changes of 23 AAs during leaf growth in Xinyang Mao Jian (XYMJ) green tea. Using amino acid analyzer, we demonstrated that most AAs are abundant on Pure Brightness Day and Grain Rain Day. After Grain Rain, 23 AAs decreased significantly. Further analysis shows that theanine has a high level on the day before Spring Equinox and Grain Rain, accounting for 44–61% of the total free AAs content in tea leaves. Glu, Pro, and Asp are the second most abundant AAs. Additionally, spinasterol and 22,23-dihydrospinasterol are first purified and identified in ethanol extract of XYMJ by silica gel column chromatography method. This study reveals the relationship between plucking days and the dynamic changes of AAs during the growth stage and proves the rationality of the traditional plucking days of XYMJ green tea.

Identification of sterols from the soft coral Dendronephthya gigantea and their anti-inflammatory potential

Exploration of anti-inflammatory phytochemicals has received tremendous attention worldwide owing to the rapid increase in inflammatory diseases. Current study reveals the identification of eight 3β-hydroxy-Δ5-steroidal congeners from a nonpolar column fraction of the ethanol solubles from the soft coral Dendronephthya gigantea collected from Jeju Island South Korea, using GC–MS/MS analysis. The sterol-rich fraction (DGEH21) showed a significant anti-inflammatory activity as exhibited by the inhibition of NO production (IC50 4.33±0.50μg/mL) and PGE2 production in LPS-stimulated RAW 264.7 macrophages. It also suppressed the expression levels of proinflammatory cytokines, TNF-α, IL-1β, and IL-6 in a dose-dependent manner. Furthermore, DGEH21 effectively downregulated the expression levels of iNOS, and COX-2 and reduced NO and ROS production as well as cell death in LPS-stimulated in-vivo zebrafish embryo model. However, DGEH21 at relatively high concentrations indicated cytotoxicity in both RAW cells and zebrafish embryos with RAW cell viability being nearly 80% after treatment with 25μg/mL DGEH21. This study highlights the synergistic anti-inflammatory activity of several steroids found in D. gigantea. Their actions may be useful in the development of anti-inflammatory cosmeceuticals, pharmaceutical agents, and other consumer products.

In vitro and in silico studies on the anticancer and apoptosis-inducing activities of the sterols identified from the soft coral, subergorgia reticulata

Background:Gorgonians and other octocorals are known to possess a huge array of secondary metabolites in which sterols are the major group of secondary metabolites apart from sesquiterpenes and diterpenes, and the bioactive metabolites could show marked biomedical potential for future drug discovery.Objective:This study was intended for the isolation and identification of sterols from the octocoral Subergorgia reticulata and to evaluate the anticancer and apoptosis-inducing activities of the identified sterols through in vitro and in silico approach.Materials and Methods:The organism was collected from Lakshadweep Island. The isolated sterols were identified using Gas chromatography-mass spectrometry (GC-MS). The structure was confirmed by using comparison of their spectra those in National Institute of Standard Technology (NIST) library. The apoptosis inducing effect of identified sterols were determined by PASS online prediction. In vitro cytotoxity studies were carried out using Dalton's lymphoma ascites cells (DLA) and the cell viability was determined by trypan blue exclusion method.Results:Six sterols were identified from the soft coral S. reticulata. They are Cholesta-5,22-diene-3ol (3β), Ergosta-5-22-dien-3ol (3β,22E 24S), Cholesterol, 26,26-Dimethyl-5,24(28)-ergostadien-3β-ol. β-sitosterol, and Fucosterol. In silico predictions showed that the identified sterols exhibited remarkable apoptosis agonist activity. The probability of apoptosis agonist activity were found maximum for 26,26-Dimethyl-5,24 (28)-S. reticulata sterol fractions isolated were found to be having anticancer activity.Conclusions:These findings suggest that S. reticulata contained biologically active sterol compounds that may be useful in the treatment of cancer.

Effects of diet and metamorphosis upon the sterol composition of the butterfly Morpho peleides

Whole body sterol metabolism in insects has seldom been studied. We were able to design an appropriate study at a butterfly farm in Belize. We collected six larvas of butterfly (Morpho peleides), their food (leaves of Pterocarpus bayessii), and their excretions. In addition, six adult butterflies were collected. The sterols of the diet, the larva, and adult butterfly were analyzed by gas-liquid chromatography. The structures of these sterols were identified by digitonin precipitation, GC-MS, and NMR. Four sterols (cholesterol, campesterol, stigmasterol, and sitosterol) and a sterol mixture were found in the food, the body, and the excreta of the larva. The tissue sterol content of the larva was 326 microg. They consumed 276 microg of sterols per day. Their excretion was 185 microg per day as sterols. The total tissue sterol contents of the larva and butterfly were similar, but they had different sterol compositions, which indicated interconversion of sterols during development. There was a progressive increase in the cholesterol content from larva to butterfly and a decrease in the content of sitosterol and other plant sterols, which were likely converted to cholesterol. Our data indicated an active sterol metabolism in butterfly larva. Diet played an important role in determining its sterol composition. During metamorphosis, there was an interconversion of sterols. This is the first paper documenting the fecal sterol excretion in insects as related to dietary intakes.

Identification of Sterols and Steroidal 3-Ones in the Seeds of Echinochloa frumentacea

Sterols and steroidal 3-ones were detected in the seeds of Echinochloa frumentacea (Roxb.) Link. Twenty sterols were identified by direct GC-MS comparison with authentic samples and the compositions of both free and esterified sterol fractions were determined. Eight steroidal 3-ones were found present in the seeds.

Identification of Sterols and Castasterone in the Seeds of Amaranthus inamoenus

Study was made of sterols and brassinosteroids in the seeds of Amaranthus inamoenus. Spinasterol was found to be the most abundant sterol (ca. 80%) and three minor sterols, 24ξ-methyl-5α-cholest-7-en-3β-ol, 24ξ-ethyl-5α-cholest-7-en-3β-ol and 24-ethyl-5α-cholesta-7, 24 (28) Z-lien-3β-ol were identified. One bioactive substance from the seeds in a rice lamina inclination test was found to be the brassinosteroid, castasterone by GC-MS. Structural relationships between sterols and castasterone are biogenetically discussed.

Sterol Constituents of Plants of Family Lauraceae

The identification of sterols obtained from the unsaponifiable lipids of stem extracts of two Lauraceae plants, Neolitsea aciculata and Litsea japonica was carried out based on chromatographic (GLC and HPLC) and mp data. Sterol composition was determined from GLC data. Some minor components were assigned on the basis of MS and NMR spectroscopic data and a comparison with authentic sterols. The major components of the two Lauraceae plants were sitosterol, campesterol and sitostanol, both sterol compositions were essentially the same. These sterol constituents were compared with those of six Lauraceae plants. Neolitsea sericea, Cinnamomum loureirii, Laurus nobilis, Machilus japonica, Lindera umbellata and Lindera obtusiloba.

Sterols of three leguminosae seeds: occurrence of 24α-ethyl-5α-cholest-9(11)-en-3β-ol and both c-24 epimers of 24-ethylcholesta-5,25-dien-3β-ol

The seeds of three Leguminosae plants, Dolichos biflorus Lathhyrus sativus and Lens culinaris, were investigated for their sterol constituents. The following uncommon sterols, in addition to several common phytosterols, were isolated and identified: 24-methylene-25-methylcholesterol and 24α-ethyl-5α-cholest-9(1 1)-en-3β-ol from D. biflorus, a mixture of clerosterol and 24-epiclerosterol, and isoavenasterol from L. sativus, and 24-methylene-25-methylcholesterol from L. culinaris. Sterol identification was undertaken mainly based on the 400 MHz 1H NMR spectroscopy.

Minor and trace sterols in marine invertebrates. 61. Isolation and structure elucidation of new A-nor sterols from the marine sponge Phakellia aruensis

An examination of the Australian sponge Phakellia aruensis led to the isolation and identification of sterols with six different nuclei. Eight new sterols were isolated which included three Δ 15-A-nor sterols, three Δ 7 -A-nor sterols, and two saturated A-nor sterols. Their structures were established through mass spectrometry and 1H-NMR spectral studies.

Identification of sterols and alcohols produced by green algae of the generaChlorella andScenedesmus by means of gas chromatography—mass spectrometry

Sterols and alcohols isolated from a collection of industrially important fresh-water green algaeChlorella kessleri, Scenedesmus acuminatus, S. acutus andS. acutus var.Tomasclli cultivated heterotrophically or autotrophically under pilot plant conditions, were identified and quantified by gas chromatography — mass spectrometry. Previsously demonstrated sterols with double bonds in position 5 and 7 were detected. In addition, cholesta-5,7,22-trien-3 β-oI that had not yet been described in green algae was found inS. acutus. Alcohols were found only inC. kessleri cultivated under heterotrophic conditions. Some saturated and unsaturated alcohols were detected for the first time in green algae.

Identification of Sterols in Submerged Cultures of Different Claviceps Species

Summary The occurence of sterols was studied by gas chromatography - mass spectrometry in the lipid fraction of saprophytic cultures of Claviceps purpures, C. paspali, C. fusiformis and C. sp. SD-58. A total of 15 sterols were found out of which 11 have not yet been described in the genus Claviceps . Comparison of biogenetic pathways of sterols was used to assess the relatedness of the strains under study.

Mass Spectrometry and Identification of Sterols in Vegetable Oils as Butyryl Esters and Relative Quantitation by Gas Chromatography with Flame Ionization Detection

Electron ionization mass spectrometry (MS) of sterol butyrates is described. Fragmentation of common sterol butyrates is related to structure and is discussed in relation to the fragmentation of free sterols and of commonly used sterol derivatives. Derivatized samples of vegetable oils are introduced using a 10 m capillary gas chromatographic (GC) column for complete separation of the sterol butyrates. Quantitation of sterol butyrates in vegetable oils by packed column GC/flame ionization detection is based on percent relative area of peaks identified by MS. Results of analyses of sunflower, castor, rapeseed, and virgin olive oils, and other oils are presented. These techniques have been applied to the rapid screening of marketed olive oils for possible adulteration.

Untersuchungen zur Sterinsynthese des Ascomyceten Aureobasidium (Dematium) pullulans / Studies of the Sterolsynthesis in the Fungus Aureobasidium (Dematium) pullulans

Abstract Isolation and identification of sterols from culture extracts of the fungus Aureobasidium (Dematium) pullulans yielded metabolites with key function in sterol synthesis. By proof of squalene, lanosterol/dihydrolanosterol, desmosterol, ergosterol, cholesterol, stigmasterol and β-sitosterol it was possible to work out a general synthesis-scheme for the building-up of sundry sterols in Ascomycetes.

Identification of sterols and bile acids by computerized gas chromatography-mass spectrometry.

In mass spectrometry, sterols and bile acids from fragment ions characteristic of certain steroid structures. After separation of derivatized sterols or bile acids by the gas chromatograph and fragmentation in the mass spectrometer, data collected by the computer can be collated to provide a reconstructed gas chromatogram and a series of fragment ion current chromatograms in which the relative abundances of characteristic fragment ions are plotted vs time or scan number. Intensities of these fragment ions will be greatest and hence coincide with peak elution of unidentified sterols or bile acids. The use of known amounts of labeled appropriate sterols of bile acids permits quantitation of the identified sterol or bile acid.

Simple mass chromatographic procedure for the detection and identification of sterols using derivative correlations

Simple mass chromatographic procedure for the detection and identification of sterols using derivative correlations

Catabolism of cholesterol by bovine adrenal-cortex enzymes: in vitro formation of oxygenated sterols and side-chain cleavage products.

The identification of sterols and steroids formed by incubation of [7alph-3H, 26-14C]cholesterol with mitochondrial enzymes from bovine adrenal cortex is reported. Only 17% of the radioactivity associated with cholesterol metabolites was found in pregnenolone, whereas 15% was reliable to oxygenated sterols and 6% to steroid compounds. The significance of the formation of these compounds is discussed particularly as regards oxygenated cholesterol derivatives.

Isolation and identification of sterols from yeasts of the genusCandida

By thin-layer chromatography on silica gel containing 20% of Supercel the following sterols have been isolated from a mixture of the sterols of the yeastCandida guilliermondii and identified: 5α-ergost-7-en-3β-ol, ergosterol, β-sitosterol, 4α-methylzymosterol, and 14α-demethyllanosterol. The amount of ergosterol in the mixture was 96%.

Isolation and identification of sterols from subcellular fractions of bean leaves ( Phaseolus vulgaris)

Chloroplasts, mitochondria and microsomes were isolated from a cell-free extract of green and etiolated leaves of bean, by differential and sucrose or ficoll gradient centrifugation. The sterols and sterol esters of whole leaves and subcellular fractions were compared. The following sterols were identified from the leaves: cholesterol (cholest-5-en-3β-ol), Δ 7-cholestenol (cholest-7-en-3β-ol), campesterol ( cholest-5-en-(24R)-24- methyl-3β-ol ), stigmasterol ( stigmast-5,Z-22- dien-3β-ol ), sitosterol (stigmast-5-en-3β-ol) and isofucosterol ( stigmast-5,Z-24(28)- dien-3β-ol ). These sterols are present in all subcellular fractions but their concentrations differ significantly; in particular the chloroplasts and the mitochondria are much richer in cholesterol (24%) compared to the leaves (1%). The amount of sterols per mg of proteins in the fractions varied as follows: chloroplasts < mitochondria < endoplasmic reticulum. Sterol esters were generally enriched in cholesterol (25–75%) and poor in stigmasterol (10%). These results are discussed in terms of the role of the sterols in the structure and function of plant cell membranes.

藍藻&lt;i&gt;Anabaena cylindrica&lt;/i&gt;におけるステロールの存在

The composition and biosynthesis of sterols in the blue-green alga, Anabaena cylindrica, were investigated. 1) From the blue-greeen alga cultivated aseptically in a defined medium, sterols were isolated by the digitonin-precipitation method. 2) The identification of sterols was performed by gas-liquid chromatography and mass spectrometry. 3) The sterols isolated from the blue-green alga were composed of brassicasterol (90%), cholesterol (8%), 22-dihydrobrassicasterol (2%), and 22-dehydrocholesterol (<1%). 4) The incubation of the blue-green alga with acetate-1-14C gave both radioactive squalene and sterols. The results suggest that the enzyme systems for biosynthesis of sterol exist in the blue-green alga under investigation.

Isolation and identification of sterols from a pleistocene sediment.

Sterols isolation and identification from Pleistocene sediment by gas-liquid chromatography and combined gas chromatography-mass spectrometry