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1.
Two morphologically ambiguous Ligularia samples (samples A and B), and samples with morphology of Ligularia subspicata (sample C), Ligularia lamarum (sample D), or Ligularia cyathiceps (sample E), were collected at Tianchi Pond, Shangrila County, Yunnan Province, China. Analysis of the nucleotide sequence of the internal transcribed spacers (ITSs) in the nuclear ribosomal RNA gene cluster indicated that not only sample B but also sample D was a hybrid of L. cyathiceps and L. lamarum/L. subspicata. Although the morphology of sample A suggested that it was also a hybrid, the ITS sequence of sample A was that of L. cyathiceps. Twenty compounds were isolated from the five samples, and the structures of two new compounds 7 and 14 were determined. Furanoeremophilanes typical of L. lamarum/L. subspicata were detected not only in samples C and D, but also in samples A and B. These results indicate that the ability to produce root chemicals can spread through introgression.  相似文献   

2.
In our survey on the chemical composition of traditional Chinese medicines to further elucidate their chemical substances for the treatment of diseases, we investigated the chemical constituents of the seeds of plants Caesalpinia minax. The investigation led to the isolation and identification of four new cassane diterpenes, caesalpines A–D (14). Their structures were elucidated on the basis of extensive 1D and 2D NMR (COSY, HMQC, HMBC, and NOESY) and mass (ESIMS and HR-ESIMS) spectroscopic data analyses. The phytochemical results imply that cassane diterpenes are maybe regarded as the characteristic constituents of C. minax.  相似文献   

3.
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Highlights► Chemical composition of Conoscyphus Trapezioides was examined. ► This is a chemotaxonomic contribution to better understanding of Conoscyphus genus. ► Two new terpenoids were isolated from C. Trapezioides. ► The structures of new terpenoids were assigned by spectroscopic data. ► This is the first occurrence of the chemical studies in the genus Conoscyphus.  相似文献   

4.
A new cuparene-type sesquiterpene, isolaurenisol, has been isolated and identified from the New Zealand red alga Laurencia distichophylla. Major differences in the chemical composition of two morphologically indistinguishable samples of L. distichophylla are noted.  相似文献   

5.
Several in situ studies have been conducted on maize silages to determine the effect of individual factors such as maturity stage, chop length and ensiling of maize crop on the rumen degradation but the information on the relationship between chemical composition and in situ rumen degradation characteristics remains scarce. The objectives of this study were to determine and describe relationships between the chemical composition and the rumen degradation characteristics of dry matter (DM), organic matter (OM), CP, starch and aNDFom (NDF assayed with a heat stable amylase and expressed exclusive of residual ash) of maize silages. In all, 75 maize silage samples were selected, with a broad range in chemical composition and quality parameters. The samples were incubated in the rumen for 2, 4, 8, 16, 32, 72 and 336 h, using the nylon bag technique. Large range was found in the rumen degradable fractions of DM, OM, CP, starch and aNDFom because of the broad range in chemical composition and quality parameters. The new database with in situ rumen degradation characteristics of DM, OM, CP, starch and aNDFom of the maize silages was obtained under uniform experimental conditions; same cows, same incubation protocol and same chemical analysis procedures. Regression equations were developed with significant predictors (P<0.05) describing moderate and weak relationships between the chemical composition and the washout fraction, rumen undegradable fraction, potentially rumen degradable fraction, fractional degradation rate and effective rumen degradable fraction of DM, OM, CP, starch and aNDFom.  相似文献   

6.
Four new glycosides, including one anthraquinone glycoside (1), one naphthalene glycoside (2), and two naphthopyrone glycosides (34), with 10 known compounds (514) were isolated from the seeds of Cassia obtusifolia L. The new structures were determined by spectroscopic analysis and chemical transformations.  相似文献   

7.
One new flavonoid glycoside, myricetin 4′-methyl ether 3-O-β-d-xylopyranoside (1) and one new natural triterpene glycoside, grandoside (2) were isolated from a MeOH extract of the leaves of Syzygium grande, together with thirteen known compounds (3–15). The structures of the new compounds were determined through a combination of spectroscopic and chemical analyses. All of the isolated compounds were evaluated for their antifungal, antibacterial, anti-leishmania, DPPH radical-scavenging and cytotoxic activities by means of MTT assay.  相似文献   

8.
Extracts of different medicinal plants had been used to control several diseases in both traditional medicine and modern drugs. In the current study, we aimed to examine the changes in chemical composition of Zilla spinosa Forssk. plants collected from different habitats in Saudi Arabia in response to spatial and seasonal variations. Z. spinosa samples were collected from two different sites in Riyadh and Eastern regions in Saudi Arabia to examine the spatial variations effects on the studied parameters. Samples were collected from both sites at two different times (3:00 PM and 3:00 AM) to examine the effect of light on the chemical content and composition of these plants. Samples was, also, collected from the same sites at two different seasons (on start of January 2018 “winter season” and end of May 2018 “summer season”) to examine the effect of temperature changes (seasonal variations) on the chemical content and composition of the different studied plants. In Z. spinosa plants collected from Riyadh region, squalene was found to be the major constitute of 3 samples; however, surprisingly, the sample collected in Winter at 3:00 AM showed the presence of mome inositol and (Z)-5-(formylmethylene)-4-methoxy-2(5 h)-furanone as the dominant components. Similarly, chemical compositions of essential oils extracted from Z. spinosa samples collected from Eastern region in the Summer season was dominated by squalene. Z. spinosa plants showed that all collected samples had high carbohydrate and protein contents with very low content of fats.  相似文献   

9.
The essential oil composition from the aerial parts of a new Eryngium species from Australia, Eryngium rosulatum P.W. Michael ined., has been analysed by GC and GC/MS. A total of 34 compounds have been identified representing around 80% of the total oil. The main constituents of the oil were found to be β-elemene (16.0%) and bicyclogermacrene (12.5%). Other representative compounds were identified as δ-elemene (7.0%) and (E)-caryophyllene (5.9%). The sesquiterpene fraction (75.0%) was predominant in the essential oil of this species, most of these were hydrocarbons (53.8%). This paper represents the first study on this new, undescribed Australian species and its chemical composition.  相似文献   

10.
Three new compounds including one C21-steroidal glycoside, one methylglycoside, and one neolignan, named as Deoxyamplexicogenin A-3-O-yl-4-O-(4-O-α-l-cymaropyranosoyl-β-d-digitoxopyranosoyl)-β-d-canaropyranoside (1), Methyl-O-α-l-cymaropyranosoyl-(1  4)-β-D-digitoxopyranoside (2), and (+)-(7S, 8R, 7E)-5-hydroxy-3, 5′-dimethoxy-4′, 7-epoxy-8, 3′-neolign-7′-ene-9, 9′-diol 9′-ethyl ether (3), respectively, were isolated from the roots of Cynanchum stauntonii. The structure elucidations were achieved by in-depth spectroscopic examination, mainly including the experiments and analyses of multiple 1D- and 2D-NMR and HRESIMS and CD analysis and qualitative chemical tests. Cytotoxicity activities of compounds 13 were evaluated against five tumor cell lines (HCT-8, Bel-7402, BGC-823, A549, and A2780) in cell based assays where they were found to be inactive.  相似文献   

11.
The composition of the essential oil from a new chemotype of Elsholtzia strobilifera Benth. collected from sub-alpine region of central Himalaya, India, has been investigated by Gas Chromatography and Gas Chromatography–Mass Spectrometry. The GC of the oil revealed the presence of more than 50 constituents, of which neral (18.3%) and geranial (29.9%) were found to be the major compounds and an absence of monoterpene hydrocarbons. Acylfuran derivatives, the specific chemical markers of the essential oils from the genus Elsholtzia were not detected.  相似文献   

12.
The chemical composition of the essential oils obtained from inflorescences, the root and herb of Ligusticum mutellina of Polish origin was studied and compared to plants collected from other locations. Analyses of L. mutellina essential oils of Polish origin revealed α-pinene as a predominant compound in the root (49.49%) and herb (9.76%), while sabinene in flowers (23.97%). The chemical composition of root essential oils from other Ligusticum species was compared to L. mutellina chemical profile. On the basis of literature data and our study, the cluster and principal component analyses were made. Both analyses showed that L. mutellina essential oil differs essentially from the others. There is some similarity between the other oils; nevertheless, PC2 suggest that four clusters can be distinguished connected with the samples origin.  相似文献   

13.
The aim of this study was to establish a method for discriminating Dendrobium officinale from four of its close relatives Dendrobium chrysanthum, Dendrobium crystallinum, Dendrobium aphyllum and Dendrobium devonianum based on chemical composition analysis. We analyzed 62 samples of 24 Dendrobium species. High performance liquid chromatography analysis confirmed that the four low molecular weight compounds 4??,5,7-trihydroxyflavanone (naringenin), 3,4-dihydroxy-4??,5-dime-thoxybibenzyl (DDB-2), 3??,4-dihydroxy-3,5??-dimethoxybibenzyl (gigantol), and 4,4??-dihydroxy-3,3??,5-trimethoxybibenzy (moscatilin), were common in the genus. The phenol-sulfuric acid method was used to quantify polysaccharides, and the monosaccharide composition of the polysaccharides was determined by gas chromatography. Stepwise discriminant analysis was used to differentiate among the five closely related species based on the chemical composition analysis. This proved to be a simple and accurate approach for discriminating among these species. The results also showed that the polysaccharide content, the amounts of the four low molecular weight compounds, and the mannose to glucose ratio, were important factors for species discriminant. Therefore, we propose that a chemical analysis based on quantification of naringenin, bibenzyl, and polysaccharides is effective for identifying D. officinale.  相似文献   

14.
Thymus pulegioides plants were collected from various natural habitats of Lithuania and transferred into a new uniform environment. The plants were cloned annually at controlled conditions and their essential oil composition was monitored by capillary GC and GC/MS. The geraniol/geranial/neral (G/G/N), thymol (T), linalool (L), carvacrol/γ-terpinene/p-cymene (C/γT/pC) and thymol/carvacrol/γ-terpinene/p-cymene (T/C/γT/pC) chemotypes of T. pulegioides were studied. It was found that according to the stability of essential oil composition on a sudden change of environmental conditions two types of T. pulegioides can be distinguished: (1) plants which preserve their chemical composition of the essential oils; (2) plants, which considerably change their chemical composition of the essential oils.  相似文献   

15.
Variations in the chemical composition of the essential oils of Minthostachys mollis Griseb. (Lamiaceae) collected in their natural habitat in Argentina were determined using GC-FID-MS analysis. Seventy five samples collected out of 40 wild plant populations in the Central and Northwestern Argentina during four years sampling, were analyzed. Principal Component Analysis was made on the chemical data showing that samples from Córdoba and San Luis belonged to the typical menthone – pulegone chemotype in accordance with previous reports; meanwhile samples from Tucumán, Salta and Catamarca showed the presence of different compositions, some previously unreported, mainly those detected in Tucumán province. In addition, cluster analysis was applied using Euclidean distance to measure the dissimilarity in the relative composition of samples from Tucumán, Salta and Catamarca, using Ward's method as the agglomeration technique. Five groups were retained with less than 10% of information loss: i) dihydrocarvone-carvone, ii) pulegone with absence of menthone, iii) carvacryl acetate-carvacrol, iv) limonene and v) linalool.It is worth mentioning that the compositions of the different chemotypes remained constant throughout the four years of collection and despite the highly diverse pattern of compositions revealed in this search, the typical chemotype was not found present northwards Córdoba and San Luis provinces. This is the first report of a deep study on natural populations of peperina throughout the whole distribution area in Argentina with consecutive sampling repetitions of the same populations during several years.  相似文献   

16.
The detailed investigation of the whole plant of Ligularia dictyoneura was performed during a search for unique chemical skeletons. One novel noreremophilane-type sesquiterpene, (4S, 5R, 8R, 10S)-1-nor-10-hydroxy-8-methoxyeremophil-7(11)-en-12,8-olide (1) and one new highly oxygenated eremophilane, 1β-angeloyloxy-6α, 10β-dihydroxyeremophil-7(11), 8-dien-12, 8-olide (2), were obtained. Their structures, including the absolute configuration, were elucidated by spectroscopic data and CD analysis.  相似文献   

17.
Constructed wetlands have been recognized as a removal treatment option for high concentrations of contaminants in agricultural waste before land application. The goal of this study was to characterize microbial composition in two constructed wetlands designed to remove contaminants from dairy washwater. Water samples were collected weekly for 11 months from two wetlands to determine the efficiency of the treatment system in removal of chemical contaminants and total and fecal coliforms. The reduction by the treatment was greatest for biological oxygen demand, suspended solids, chemical oxygen demand, nitrate, and coliforms. There was only moderate removal of total nitrogen and phosphorus. Changes in the total bacterial community and ammonia-oxidizing bacterial composition were examined by using denaturing gradient gel electrophoresis (DGGE) and sequencing of PCR-amplified fragments of the gene carrying the α subunit of the ammonia monooxygenase gene (amoA) recovered from soil samples and DGGE bands. DGGE analysis of wetlands and manure samples revealed that the total bacterial community composition was dominated by bacteria from phylogenetic clusters related to Bacillus, Clostridium, Mycoplasma, Eubacterium, and Proteobacteria originally retrieved from the gastrointestinal tracts of mammals. The population of ammonia-oxidizing bacteria showed a higher percentage of Nitrosospira-like sequences from the wetland samples, while a higher percentage of Nitrosomonas-like sequences from manure, feces, raw washwater, and facultative pond was found. These results show that the wetland system is a natural process dependent upon the development of healthy microbial communities for optimal wastewater treatment.  相似文献   

18.
Investigation of a small number of samples with representatives of the genus Diaphanosoma from the cladoceran collection of the National Museum of Natural History, Smithsonian Institution (Washington, D.C., U.S.A.) has revealed two new species, D. freyi and D. heberti, from Louisiana–Missouri and Newfoundland, respectively. The former looks like one of the most primitive species of the genus. Two other species, D. fluviatile and D. brevireme, are recorded from the southern United States for the first time. Members of the D. brachyurum and D. birgei species groups, which are morphologically variable and need further detailed investigations, were represented in the bulk of the material studied. The species richness of the genus in North America appears to be high and its composition is obviously complex but remains little studied.  相似文献   

19.
A common Great Barrier Reef sponge, previously attributed to the genus Spongia, is described as new and placed in a new genus Rhopaloeides. This genus includes Spongiidae otherwise identical to Spongia in which the cored primary fibres form simple fascicles. The genus is also characterized by its form (massive, thick broad-based lamellae or multiple fused thick clubs). The chemistry is distinctive, characterised by possession of a rare group of C 20 diterpene furanodiols, triols and their peracetates. Considerable variation in the total yield and composition of the diterpenes for different collections of R. odorabile was confusing and led to a suggestion that more than one species was represented. Field experiments in which fragments of one individual sponge were transplanted to different conditions of illumination and depth, demonstrate that the chemical variability reflects the range of environmental conditions under which R. odorabile lives rather than any genetic differences.  相似文献   

20.
Root chemicals and the sequences of the internal transcribed spacers (ITSs) were analyzed for 9 Ligularia kanaitzensis and 3 L. subspicata samples collected in northwestern Yunnan and southwestern Sichuan, China. Subspicatins A and C were isolated from two L. kanaitzensis samples. Introgression of genes responsible for these compounds from L. subspicata was suggested by their strong connection with L. subspicata/L. lamarum and the geographical proximity of the samples to L. subspicata. DNA analysis of a set of 27 L. kanaitzensis samples including those analyzed previously showed that they belong to two clades, designated A and B. Together with the presence/absence of furanoeremophilane, the 27 samples were sorted into three groups: clade A/furan, clade B/furan, and clade B/non-furan. The ancestral plant presumably belonged to clade B/non-furan, because furanoeremophilanes are biosynthesized from eremophilan-8-ones. 1β-Angeloyloxyfukinone, a likely intermediate between fukinone and subspicatin C, was isolated for the first time. This finding allowed us to propose plausible biosynthetic pathways of subspicatins A and C.  相似文献   

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