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The aerial parts from Blutaparon portulacoides yielded a flavonol whose structure was established as 3,5,3'-trihydroxy-4'-methoxy-6,7-methylenedioxyflavone. In addition, the aerial parts yielded the isoflavone irisone B and the steroids stigmasterol, sitosterol and campesterol. The roots of B. portucaloides furnished sitosteryl, stigmast-7-enyl and spinasteryl beta-D-glucopyranosides as well as vanillic acid.
The structures of two new monodesmosidic and bisdesmosidic triterpenoid saponins (1 and 2) and the known compound delta 5-stigmasterol-3-O-beta-D-glucopyranoside (3) as well as two new oleanane type triterpene lactone glycosides 4, 5 and a new sapogenin lactone 6 isolated from the stem bark of Albizia gummifera C.A. Smith (Mimosaceae) have been elucidated as 3-O-¿beta-D-glucopyranosyl(1-->2)-[alpha-L-arabinopyranosyl(1-->6) ]-beta-D- glucopyranosyl¿-oleanolic acid (1), beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl 3-O-¿beta-D-glucopyra-nosyl(1-->2)-[alpha-L-arabinopyrano syl(1-->6)]-beta-D- glucopyranosyl¿-oleanolate (2), 3 beta-¿O-D-glucopyranosyl-(1-->2)-[O-alpha-L-arabinopyranosyl(1-->6 )] beta-D-glucopyranosyloxy¿-machaerinic acid gamma-lactone (4), 3 beta-O-beta-D-glucopyranosiduronic acid (1-->2)-beta-D-glucopyranosyloxy]-machaerinic acid gamma-lactone (5), and A-homo-3a-oxa-5 beta-olean-12-en-3-one-28-oic acid (6), respectively. The complete assignment of the 1H and 13C resonances of 1, 2, 4 and 6 and of the peracetate of 5 were achieved by means of 2D-NMR studies.
This paper elaborates an improved synthesis of crinosterol and campesterol starting from stigmasterol. The proposed approach is based on Claisen rearrangement of Delta23-22-allylic alcohols with various configurations of the 22-hydroxy group and geometry of the Delta23-double bond. It allows complete use of the starting steroid for preparing 24alpha-methyl derivatives. It was possible to partially control the stereochemistry at C-25. Hydrogenation of the Delta22-double bond was shown to proceed with partial isomerization of the C-24 alkyl substituent. The Ireland ester enolate variant of the Claisen rearrangement was demonstrated to be useful for preparing 24alpha-methyl steroids containing the Delta22,25-system.
We report on the synthesis of the brassinosteroid analogs (22R,23R)-3 beta, 7 beta, 22,23-tetrahydroxy-stigmast-5-ene (13), (22R,23R)-3 beta, 7 alpha, 22,23-tetrahydroxy-stigmast-5-ene (15), and (22R,23R)-3 beta, 22,23-trihydroxy-stigmast-5,7-diene (18) by means of the osmium-catalyzed asymmetric dihydroxylation of intermediate 1, available from stigmasterol. This reaction sequence produced the expected (22S,23S)- and (22R,23R)-triols 6 and 7 as well as the 22,23-diketo derivatives 2 and 3. The phytohormone activity of the new brassinosteroid analogs is discussed.
A patient with phytosterolemia and type IIa hyperlipoproteinemia with tuberous xanthomas is described. The plant sterols, beta-sitosterol, campesterol, and stigmasterol, were identified in plasma and the xanthomas; to our knowledge, this is the first case of phytosterolemia and xanthomatosis in a Japanese.
The previously demonstrated mutagenicity of naturally air-aged (autoxidized) USP cholesterol in test strains of Salmonella typhimurium has been confirmed. In contrast, autoxidized brassicasterol, 7-dehydrocholesterol, ergosterol, lanosterol, sitosterol, and stigmasterol were non-mutagenic in the same assay, and 38 individual cholesterol derivatives, including many cholesterol autoxidation products, were also non-mutagenic. The mutagenic species from mutagenic cholesterol preparations were shown to be neutral steroids that are very much more polar than the cholesterol autoxidation products so far identified. High-performance liquid chromatography resolved mutagenic cholesterol preparations into several mutagenic and non-mutagenic fractions. The chemical nature of the mutagens is suggested as involving oxidation of the sterol B-ring and of the side-chain.
A study was conducted in 12 healthy males and 12 healthy females (mean age 36 years, mean body mass index 24 kg/m2), to determine the effect of a margarine enriched with phytosterol esters on faecal short-chain fatty acids (SCFAs) and faecal bacterial enzyme activities, viable faecal microflora count, female sex hormones and serum cholesterol concentrations. The study design was a two-period, parallel dosing, randomized, placebo-controlled dietary study. Under controlled dietary conditions, participants consumed 40 g of the control margarine for 21 and 28 consecutive days for males and females, respectively. This was followed immediately by the second part of the study where subjects were equally and randomly allocated to consume daily 40 g of either the control or the test margarine, containing 8.6 g vegetable oil phytosterols (a mixture of beta-sitosterol, campesterol and stigmasterol), also for 21 or 28 days. All females were shown to have a regular menstrual cycle and were on an established method of contraception not involving oral contraceptives. When compared with the control group values, the test group showed a significant reduction in serum total and LDL cholesterol concentrations of 18 and 23% (P < 0.001; P < 0.001) respectively, in faecal lactic acid concentration (P = 0.039) and in serum progesterone levels (P = 0.021). There were no other significant treatment effects. Within each group a number of significant changes occurred compared to baseline. In the test group, faecal lactic acid concentration and the ratio of acetic acid:total SCFA; and the ratio of butyric acid:total SCFA, in the control group were both significantly reduced (P = 0.016). Compared to baseline, azo-reductase activity was significantly reduced in the control group (P = 0.047). Total faecal aerobes (P = 0.028), lactobacilli (P = 0.003) and staphylococci (P = 0.025) content was also significantly reduced in the control group, while in the test group only lactobacilli content was reduced (P = 0.019). Of the significant findings reported in this study, none was considered to be of biological importance except the beneficial reduction in serum total and LDL-cholesterol concentrations. The daily consumption of a margarine enriched with 8.6 g vegetable oil phytosterols did not affect the bacterial profile or the metabolic activities of the gut microflora, nor did it result in biologically relevant effects on serum female sex hormone levels. The margarine enriched with the vegetable oil phytosterols was well tolerated by both male and female volunteers.
Twenty-six epidemics of asthma occurred in Barcelona between 1981 and 1987 in relation to inhalation of soy dust from grain silo unloading in the harbor. No further epidemics occurred after filters were installed, until a 1994 outbreak of asthma due to soy was detected in L'Hospitalet de Llobregat, a city on the outskirts of Barcelona. We describe 9 patients who presented with acute asthma attacks of sudden onset within a time span of 135 minutes. Counts of total IgE and IgE specific to soy extract were analyzed in all patients. Skin prick tests confirmed exposure to soy in all cases. Atmospheric levels of alcoholic fractions of soy particles (beta-sitosterol and stigmasterol) registered in L'Hospitalet de Llobregat were higher than those detected in Barcelona. We confirmed that soy had been unloaded in the harbor the same day, and that climatic conditions favored the movement of air from the port toward the city of L'Hospitalet. We postulate the need to periodically review preventive measures given the potential severity of the such epidemics.
This paper presents the content and composition of free sterols in a number of Astragalus species from Iran. Free sterols of roots and seeds were analysed quantitatively and qualitatively by gas-liquid chromatography. Four major 3-beta-hydroxysterols (cholesterol, campesterol, stigmasterol and beta-sitosterol) were identified in roots of 18 species and in seeds of five species of Astragalus. beta-Sitosterol was the main free sterol in both roots and seeds. The cholesterol content in seeds was higher than that in roots. Trace amounts of cholesterol were detected in roots of only four species. beta-Sitosterol accounted for 34.4-69.2 and 76.8-81.8% of the total lipid content in roots and seeds, respectively. The beta-sitosterol content in roots and seeds of Astragalus species varied from 6.3 to 35.7 and 93.3 to 164.5mg/100g dry weight, respectively. Total free sterol content in seeds varied from 112.09 to 204.04mg/100g dry weight, significantly higher than those in roots (7.5 to 43.4mg/100g dry weight). The chemotaxonomic values of free sterols and total lipid profiles of some of the representative species are discussed.
The isolation of (-)-arctiin (1), arctigenin (2), onopordopicrin (3), kaempferide, eriodictyol, luteolin and stigmasterol from the aerial parts of Carduus micropterus ssp. perspinosus, is reported.
A new triterpene, 3beta-19alpha-dihydroxy-30-norurs-12-ene (1), has been isolated from the methanolic extract of Debregeasia salicifolia stems. Its structure has been elucidated with the help of one- and two-dimensional NMR and NOE studies. Lupeol, beta-sitosterol, stigmasterol and oleanolic acid are also reported for the first time from this species.
Total lipid extraction, solid-phase extraction, saponification, derivatization to trimethylsilyl ether derivatives, then capillary gas-liquid chromatography were used for quantitative analysis of sitosterol, campesterol, stigmasterol, sitostanol, campestanol, lathosterol, desmosterol, and lanosterol in human serum. Details of quality control integral to the accuracy and precision of analyses are included. The method limits of detection and quantitation, respectively, ranged from 0.05 microg/ml and 0.2 microg/ml for sitostanol to 0.4 microg/ml and 1.2 microg/ml for campesterol and campestanol. Analytes were measured at concentrations of 120 ng/ml to 6 microg/ml with standard deviations of 0.02 to 0.12 microg/ml for 55 analyses of a control serum sample conducted over a 2-month period.
The antimicrobial properties of the hexane extract from the leaves and twigs of the Eupatorium glutinosum was tested against two Gram-negative and two Gram-positive bacteria. Bioassay guided fractionation leads characteristically to isolation and structure elucidation of two active compounds: 15-hydroxy-7-labden-17-oic acid and its acetate. These results validate the vernacular medicinal uses of the plant in folkloric medicine. Dammara-20, 24-dien-3-acetate, stigmasterol and epi-friedelanone have been also isolated in addition to the palmitate of nepehinol for the first time as naturally occurring.
Fatty acids (FA), hydrocarbons, alpha-amyrin, stigmasterol and beta-sitosterol were identified in the n-hexane extract of the aerial parts of Sideritis taurica Stephan ex Wild. Xanthotoxin, as well as 2-acetyl-3-hydroxy-5,6,8-trimethoxy-1,4-naphthoquinone were isolated from the methylene chloride extract of the plant. In addition to apigenin 7-O-beta-D-glucopyranoside and apigenin, previously reported from the plant, hypolaetin 7-O-beta-D-allopyranosyl-O-beta-D-glucopyranoside was isolated from the ethyl acetate extract. From the methanol extract, isoscutellarein 7-O-beta-D-allopyranosyl-O-beta-D-glucopyranoside was also isolated. Toxicity study of petroleum ether extract (f(1)), ethanolic extract (f(2)), dichloromethane fraction of f(2) (f(3)) and n-butanolic fraction of f(2) (f(4)) of the plant proved that it is relatively nontoxic. The tested extracts and fractions exhibited significant analgesic, anti-inflammatory, anti-ulcerogenic and antihyperglycaemic activities, but no anticonvulsant and antipyretic effects, as compared with control groups and reference drugs.
In the methanolic extract of Croton urucurana Baillon (Euphorbiaceae) a number of known compounds, such as acetyl aleuritolic acid, stigmasterol, beta-sitosterol, campesterol, beta-sitosterol-O-glucoside, sonderianin, catechin and gallocatechin were isolated and identified by MS and NMR spectroscopy, HRGC and data from literature. The antibacterial activity of the aqueous-EtOH extract, some fractions of the methanolic extract and some of the isolated compounds, were tested against Staphylococcus aureus and Salmonella typhimurium. Acetyl aleuritolic acid exhibits the best minimum inhibitory concentration (MIC) against both Staphylococcus aureus and Salmonella typhimurium.
Phytochemical and pharmacological studies of Croton cajucara were oriented by traditional medicine. The stem bark of the mature plant is a rich source of clerodane-type diterpenes: trans-dehydrocrotonin (DCTN), trans-crotonin (CTN), cis-cajucarin B, cajucarin A, cajucarinolide and two novel clerodanes, trans-cajucarin B and sacacarin. In young (18-month-old) plants, the triterpene acetyl aleuritolic acid (AAA) was the major stem bark component and in these the diterpene DCTN was not present. The highest concentration of DCTN (1.4% of dry bark) was detected in 4-6 year-old plants, while 3-year-old plants contained only 0.26% of this diterpene. Three steroids (beta-sitosterol, stigmasterol and sitosterol-3-O-beta-glucoside), two flavonoids (kaempferol 3,4', 7-trimethyl ether and 3,7-dimethyl ether) and one diterpene (cajucarinolide) were isolated from the leaves of this Croton. The main pharmacological activity was correlated with DCTN. This clerodane produced anti-inflammatory and antinociceptive effects and a significant hypoglycemia in alloxan-induced diabetic rats. The compound also reduced the index of gastric lesions induced by restraint-in-cold. Dose-related DCTN and CTN inhibited in vivo the basal acid secretion in pylorus-ligature rats and oxyntic glands isolated from rabbit gastric mucosa, DCTN, CTN or AAA decreased in vitro uptake basal acid secretion induced by histamine and measured with the 14C-aminopyrine uptake method. Uniquely DCTN inhibited 14C-AP uptake induced by bethanechol. The terpenoids, DCTN and AAA, and the chloroform extract of 6-month-old plants reduced gastrointestinal transit in mice. The effects of DCTN and CTN on the survival of mice bearing Sarcoma 180 and Ehrlich carcinoma ascitic tumors, on the proliferation of cultured cells and TNFalpha were determined. DCTN was also evaluated for a possible antioestrogenic activity using the immature rat as a model system for bioassay of oestrogen and for an anti-implantation effect in regularly cycling rats. The biological experiments, using the plant extracts and the terpenoids DCTN, CTN and AAA, are herein discussed.
The present study was conducted in order to isolate and identify the phytochemical constituents responsible for analgesic effects shown by a methanolic extract obtained from Sebastiania schottiana roots. Conventional chromatographic procedures led to the isolation of moretenone, glutinol, beta-sitosterol and stigmasterol. The structural elucidation of these compounds was done on the basis of spectral data (IR, 1H- and 13C-NMR) and comparison with authentic samples. Either glutinol or moretenone exhibited marked analgesic action against acetic acid induced abdominal constrictions in mice by intraperitoneal route, indicating 16 to 26-fold higher efficacy than aspirin and paracetamol. When analyzed in a formal-in test, both compounds and standard drugs inhibited only the second phase (inflammatory pain). Our results suggest that the roots of S. schottiana contain analgesic compounds which justify, at least partially, the popular use of this plant for the treatment of urinary problems.
The Vibrio cholerae cytolysin (VCC) 63-kDa monomer has been shown to interact in aqueous suspension with cholesterol microcystals to produce a ring/pore-like heptameric oligomer approximately 8 nm in outer diameter. Transmission electron microscopy data were produced from cholesterol samples adsorbed to carbon support films, spread across the holes of holey carbon films, and negatively stained with ammonium molybdate. The VCC oligomers initially attach to the edge of the stacked cholesterol bilayers and with increasing time cover the two planar surfaces. VCC oligomers are also released into solution, with some tendency to cluster, possibly via the hydrophobic membrane-spanning domain. At the air/water interface, the VCC oligomers are likely to be selectively oriented with the hydrophobic domain facing the air. Despite some molecular disorder/plasticity within the oligomers, multivariate statistical analysis and rotational self-correlation using IMAGIC-5 strongly suggest the presence of sevenfold rotational symmetry. To correlate the electron microscopy data with on-going biochemical and permeability studies using liposomes of varying lipid composition, the direct interaction of VCC with several cholesterol derivatives and other steroids has been examined. 19-Hydroxycholesterol and 7 beta-hydroxycholesterol both induce VCC oligomerization. beta-Estradiol, which does not possess an aliphatic side chain, also efficiently induces VCC oligomer formation, as does cholesteryl acetate. Cholesteryl stearate and oleate and the C22 (2-trifluoroacetyl)naphthyloxy analogue of cholesterol fail to induce VCC oligomerization, but binding of the monomer to the surface of these steroids does occur. Stigmasterol has little tendency to induce oligomer formation, and oligomers are largely confined to the edge of the bilayers; ergosterol has even less oligomerization ability. Attempts to solubilize and stabilize the VCC oligomers from cholesterol suspensions have been pursued using the neutral surfactant octylglucoside. Although individual solubilized oligomers have been defined which exhibit a characteristic cytolysin channel conformation in the side-on orientation, a tendency remains for the oligomers to cluster via their hydrophobic domains.