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1.
2.
A new apotirucallane-type triterpenoid, 3α-benzoate triterpenoid A (1), along with six known triterpenoids (2–7), one aromatic ester (8) and eight lignans (9–16), were isolated from the fruits of Melia azedarach Linn. The structure of 1 was determined by spectral analyses, including HR-ESI-MS, 1D NMR (1H NMR and 13C NMR) and 2D NMR (HSQC and HMBC) analyses. 10, 11 and 16 were reported for the first time from the family Meliaceae, 8 was identified from the genus Melia for the first time, and 2, 3, 5, 7, 9 and 12–15 were obtained from M. azedarach for the first time. The chemotaxonomic significance of these compounds is discussed.  相似文献   

3.
The phytochemical study of the pericarps of Zanthoxylum bungeanum Maxim under the guidance of bioactivity led to the isolation of 18 compounds, including a new isobutylhydroxyamide (1) and 17 known compounds, i.e. six alkylamides (27), five coumarins (812), one benzene derivative (13), three flavonoids (1416), and two sterols (1718). Their structures were elucidated based on extensive spectroscopic methods (HRESIMS, 1D and 2D NMR experiments) and by comparison with literature data. New compound (1) and known compound (2) are cis-trans isomeric isobutylhydroxyamides. Among them, compounds 9, 10, and 12 were isolated for the first time from Z. bungeanum, compound 11 was firstly recovered from the genus Zanthoxylum, and compound 14 was reported for the first time from the Rutaceae family. The chemotaxonomic significance of isolated compounds from Z. bungeanum is discussed.  相似文献   

4.
Phytochemical investigations of the dried and nearly ripe fruits of Evodia rutaecarpa (Juss.) Benth. var. of officinalis (Dode) Huang (family Rutaceae) led to the isolation of twenty compounds, including eight quinolone alkaloids (18), seven indole quinazoline alkaloids (915), two limonoids (1617) and three sterols (1820). The chemical structures of these compounds were elucidated by extensive spectroscopic analyses and by comparison with the literature data. Notably, seven compounds (1, 3, 7, 11 and 1315) were reported from this species for the first time, and the chemotaxonomic significance of these compounds was discussed.  相似文献   

5.
We tested two general hypotheses for the diversity of native and exotic plants in an undisturbed, naturally fragmented sagebrush-steppe landscape in SE Idaho, USA, evaluating whether the MacArthur–Wilson hypothesis of island biogeography or a suite of environmental variables explained the distributions of native and exotic plants. We also tested a third hypothesis, which incorporated assumptions about the origin of exotic plants and their interaction with native plants. Of the three hypotheses we tested, the hypothesis that included exotic species best explained the diversity of the native plant community. The MacArthur–Wilson model of island biogeography did not explain the diversity of native (R 2 = 0.13) or exotic plants well (R 2 = 0.11), and the model fit the data poorly. A model of environmental variables better explained the diversity of native (R 2 = 0.48) and exotic plants (R 2 = 0.57), but it also fit the data poorly. Instead, proximity to a railroad explained the cover (R 2 = 0.59) and richness of exotic plants (R 2 = 0.63), which then explained the species richness of native plants (R 2 = 0.34), and the model fit was adequate and had the lowest AIC value. This suggests that the transportation corridor had a significant, though indirect, effect on the native plant community, even in this undisturbed area. Moreover, explained variance, model fit, and the AIC model selection criteria favored the model with the railroad and exotic species over the M–W and environmental models. Since the habitat patches we studied were largely undisturbed by people and their activities, our results further suggest that the transportation corridor influenced the distribution of exotic plants by serving as a vector for colonization, rather than as a source of disturbance. Additionally, the results suggest that exotic plant species have had a negative effect on the diversity of the native plant community and have changed its composition. The results also support the inference that the nascent exotic plant community is influenced by source-sink (Pulliam in Am Nat 132:652–661, 1988) and assembly dynamics. In contrast, the native plant community appears to be more strongly influenced by environmental conditions associated with an elevational gradient, but there is evidence that the native community also has undergone directional change in species composition, associated with the invasion by non-native species.  相似文献   

6.
To investigate the genetic diversity and phylogenetic relationships between polyploid Leymus and related diploid species of the Triticeae tribe, inter-simple sequence repeats (ISSR) markers was used to analyze 41 Leymus accessions representing 22 species and 2 subspecies, together with Pseudoroegneria stipifolia (St), Psathyrostachys fragilis (Ns), Australopyrum retrofractum (W), Hordeum bogdanii, H. chilense (H) and Lophopyrum elongatum (Ee). A total of 376 clear and reproducible DNA fragments were amplified by 29 ISSR primers, among which 368 (97.87%) fragments were found to be polymorphic. 8–18 polymorphic bands were amplified by each polymorphic primer, with an average of 12.69 bands. The data of 376 ISSR bands were used to generate Nei’s similarity coefficients and to construct a dendrogram by means of UPGMA. The similarity coefficients data suggested great genetic diversity in genus Leymus and related diploid Triticeae species, the genetic diversity among the different species more abundant than that of the different accessions. The dendrogram and principal coordinate analysis showed explicit interspecific relationships and demonstrated close phylogenetic relationships between Leymus species and Psathyrostachys.  相似文献   

7.
Sinojackia huangmeiensis is a critically endangered tree species in the Styracaceae endemic to China. To create tools to better evaluate the genetic diversity of this species, we used a modified genomic library enrichment method, the PETUER (Probe Extension and TEACl Universal EnRichment) method, to develop genetic markers. The resulting 18 microsatellite loci had high polymorphism with 3–12 alleles per locus and showed negligible stutter. Observed (HO) heterozygosities were 0.057–0.724, and polymorphism information content (PIC) was 0.109–0.794. No significant linkage disequilibrium between pairs of loci was found. All 123 individuals found in the National Natural Reserve of Longgan Lake was genotyped at the 18 loci and used to estimate a UPGMA dendrogram. Using an iterative clustering method, a set of 18 individuals was established as a core collection to represent genetic diversity and would be useful to facilitate the conservation for S. huangmeiensis. In addition, we tested the 18 loci for cross-species amplification in three other Sinojackia species and the closely related Changiostyrax dolichocarpa. These polymorphic loci will be valuable for future population genetic and phylogenetic studies of S. huangmeiensis and congeneric species, as well as in closely related Styracaceae.  相似文献   

8.
Cedrela lilloi C. DC. (cedro coya, Meliaceae), an important south American timber species, has been historically overexploited through selective logging in Argentine Yungas Rainforest. Management and conservation programs of the species require knowledge of its genetic variation patterns; however, no information is available. Molecular genetic variability of the species was characterized to identify high‐priority populations for conservation and domestication purposes. Fourteen native populations (160 individuals) along a latitudinal gradient and with different logging's intensities were assessed by 293 polymorphic AFLP (amplified fragment length polymorphism) markers. Genetic diversity was low (Ht = 0.135), according to marginal location of the species in Argentina. Most of the diversity was distributed within populations (87%). Northern populations showed significant higher genetic diversity (R2= 0.69) that agreed with latitudinal pattern of distribution of taxonomic diversity in the Yungas. Three clusters were identified by Bayesian analysis in correspondence with northern, central, and southern Yungas. An analysis of molecular variance (AMOVA) revealed significant genetic differences among latitudinal clusters even when logging (ΦRT = 0.07) and unlogging populations (ΦPT = 0.10) were separately analyzed. Loss of genetic diversity with increasing logging intensity was observed between neighboring populations with different disturbance (ΦPT = 0.03–0.10). Bottlenecks in disturbed populations are suggested as the main cause. Our results emphasize both: the necessity of maintaining the genetic diversity in protected areas that appear as possible long‐term refuges of the species; and to rescue for the national system of protected areas some high genetic diversity populations that are on private fields.  相似文献   

9.
10.
Actinomycete strain SA198, isolated from a Saharan soil sample of Algeria, exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria, and phytopathogenic and toxinogenic fungi. The morphological and chemotaxonomic characteristics of the strain were consistent with those of the genus Saccharothrix. Analysis of the 16S rRNA gene sequence of strain SA198 showed a similarity level ranging between 97.2 and 98.8% within Saccharothrix species, S. australiensis being the most closely related. Two new active products were isolated by reverse HPLC using a C18 column. The ultraviolet–visible (UV–VIS), infrared (IR), mass, and 1H and 14C nuclear magnetic resonance (NMR) spectra showed that these products were new bioactive compounds. The minimum inhibitory concentrations of these antibiotics showed a strong activity against fungi and moderate activities against Gram-positive and Gram-negative bacteria.  相似文献   

11.
Two A-seco-limonoids, accorded the trivial names, uguenensene and uguenensone and a C-7 prenylated flavonoid, uguenenprenol were isolated from Vepris uguenensis (Rutaceae). In addition, 11 known compounds, niloticin, chisocheton A, kihadalactone A, limonyl acetate, methyl uguenenoate, 7-O-methylaromadenrin, flindersiamine, 8α,11-elemodiol, tricoccin S13 acetate, skimmianine, and lupeol were isolated. The structures of the compounds were elucidated and characterized by spectroscopic analyses (NMR, GC–MS and IR). Antioxidant activity of the isolated compounds showed that uguenenprenol and 7-O-methylaromadenrin are good antioxidant agents. Significantly high antioxidant activity was also exhibited by 8α,11-elemodiol, which was 72% at 250 μg mL−1 and 57% at 15.62 μg mL−1 when tested with the deoxyribose method. The two liminoids fit nicely into the biosynthetic pathway from niloticin to methyl uguenenoate.  相似文献   

12.
Phytochemical investigation of the roots of Cola rostrata K. Schum. led to the isolation of a new unsaturated fatty acid, named rostratanic acid (1), together with fourteen known compounds, lignoceric acid, friedelan (7), friedelanone (8), bauerenol (3), lupeol (4), herranone (9), acotatarone A (11), betulinic acid (6), betulin (5), nonanedioc acid (2), arjunolic acid (10) stigmasterol, β−sitosterol, and β−sitosterol-3-O-β-D-glucopyranoside. The structure of the new compound as well as those of the known compounds were established by means of spectroscopic methods: NMR analysis (1H and 13C NMR, 1H–1H–COSY, HSQC and HMBC) and high-resolution mass spectrometry (HR-ESI-MS), and by comparison with previously reported data. Two of those known compounds were modified chemically to afford three new derivatives. All those compounds were tested for their cytotoxic activity against the human cervix carcinoma KB-3-1 cells and their antibacterial activity against Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa and Staphylococcus aureus. Although the crude extract gave weak antibacterial activity, none of the isolated compounds showed antibacterial activity, and, only the prenylated derivative showed weak cytotoxicity. In addition, the chemotaxonomic significance of the species Cola rostrata is discussed.  相似文献   

13.
The abundance and diversity of amoA genes of ammonia-oxidizing archaea (AOA) and bacteria (AOB) were investigated in ten wastewater treatment systems (WTSs) by polymerase chain reaction (PCR), cloning, sequencing, and quantitative real-time PCR (qPCR). The ten WTSs included four full-scale municipal WTSs, three full-scale industrial WTSs, and three lab-scale WTSs. AOB were present in all the WTSs, whereas AOA were detected in nine WTSs. QPCR data showed that AOB amoA genes (4.625?×?104–9.99?×?109 copies g?1 sludge) outnumbered AOA amoA genes (<limit of detection–1.90?×?107 copies g?1 sludge) in each WTS, indicating that AOB may play an important role than AOA in ammonia oxidization in WTSs. Interestingly, it was found that AOA and AOB coexisted with anaerobic ammonia oxidation (anammox) bacteria in three anammox WTSs with relatively higher abundance. In a full-scale industrial WTS where effluent ammonia was higher than influent ammonia, both AOA and AOB showed higher abundance. The phylogenetic analysis of AOB amoA genes showed that genera Nitrosomonas was the most dominant species in the ten WTSs; Nitrosomonas europaea cluster was the dominant major cluster, followed by Nitrosomonas-like cluster and Nitrosomonas oligotropha cluster; and AOB species showed higher diversity than AOA species. AOA were found to be affiliated with two major clusters: Nitrososphaera cluster and Nitrosopumilus cluster. Nitrososphaera cluster was the most dominant species in different samples and distributed worldwide.  相似文献   

14.
《农业工程》2022,42(6):653-660
The present study was undertaken in the natural temperate Himalayan forests of Himachal Pradesh, India, to assess the tree species composition and diversity. For this purpose, six major forest types (FT) viz., FT1- Upper Himalayan Pinus roxburghii forest, FT2- Quercus leucotrichophora forest, FT3- Low-level P. wallichiana forest, FT4- Moist C. deodara forest, FT5- Western Mixed Coniferous Forest, FT6- Pinus gerardiana forest were selected. Detailed sampling was carried out in these forest types, and the sample plots in each forest type were laid out using the stratified random approach. Tree stem density varied from 191.11 N ha?1 (FT6) to 441.11 N ha?1 (FT2), whereas the tree total basal cover varied from 20.01 m2 ha?1 (FT6) to 47.59 m2 ha?1 (FT5). The diversity indices reflected that a total of 21 tree species (16 genera, 11 families) were identified, with tree species richness ranging from 3 (FT6) to 9 (FT1 & FT5). The forest type FT5 recorded the maximum Shannon index of diversity (2.36), Simpson Index of diversity (0.75), Margalef's Index of richness (1.37), pielou equitability (0.74), menheink index of species richness (0.49), whereas the highest Shannon Index of diversity (0.73) and species heterogeneity (0.85) in FT6 forest type. Furthermore, dominance-diversity (d-d) curves drawn that all the six forest types showed geometric curves reveals that one or two tree species are dominant in a particular forest type. Simultaneously, the research area's species diversity, tree stem density, and tree total basal cover were equivalent to those seen in other sections of Western Himalayas.  相似文献   

15.
Sequence-Related Amplified Polymorphism (SRAP) markers were used for genetic diversity assessment and cultivar identification among 31 cultivars of jute belonging to two cultivated species Corchours olitorius L. and C. capsularis L. Forty-three primer-pairs produced a total of 394 bands with an average of 9 bands per primer pair and 89% bands were polymorphic across the genotypes of two species. Average genetic diversity in the cultivars of C. olitorius and C. capsularis was 7.2% (range 2.8–12.3%) and 7.6% (range 2.2–13.1%), respectively. Jute cultivars JRC 698, JRC 7447, TJ 40, S19 and JRO 3690 were more diverse compared to rest of the cultivars. UPGMA cluster analysis grouped all cultivars into two clusters which were representative of C. olitorius and C. capsularis species. All the cultivars could be unequivocally differentiated from one another based on the pooled profile of 43 primer-pairs, however, 24 of 31 cultivars could be identified uniquely. The probability of chance identity of any two cultivars based on SRAP markers was very low and was 6.95?×?10?07 and 2.23?×?10?07 for cultivars of C. capsularis and C. olitorius, respectively. Primer-pairs EM1-ME5, EM4-ME1, EM8-ME1 and EM10-ME1 were found to be useful for genetic diversity and cultivar identification. Our results show that SRAP markers could be effectively used for genetic diversity analyses in jute. For poor genetic diversity and resulting narrow genetic base, these markers will prove to be highly useful for identifying elite germplasm in a jute breeding program.  相似文献   

16.
A total of 73 ethanol extracts from different anatomical parts of 44 plant species belonging to 24 families, native to the Mid-Western region of Brazil, were assessed in vitro for their effect on the reproductive cycle of engorged females of the cattle tick Rhipicephalus (Boophilus) microplus, using the adult immersion test. All extracts were evaluated at the concentration of 0.2 % and, among the extracts tested, the one obtained from the fruits of Guarea kunthiana (Meliaceae) proved to be highly efficacious, showing 99.1 % of product effectiveness. Extracts from other three species were shown to be moderately active, namely Nymphaea amazonum trunk (Nymphaeaceae) [51.7 %], Strychnos pseudoquina trunk (Loganiaceae) [8.0 %] and Ocotea lancifolia leaves (Lauraceae) [34.5 %], while the remaining extracts were shown to be weakly active or inactive. This is the first report on the bioactivity of these species on egg production by engorged females of R. microplus.  相似文献   

17.
Pyrroles and pyrrolo[2,3-d]pyrimidines were reported to act as potent anticancer agents, in this work, a series of novel 2-substituted-3-cyano-4-phenyl-pyrrole 5, 6, 1118, and 5-phenyl-pyrrolo[2,3-d]pyrimidine derivatives 710, 1924 bearing either sulfathiazole or sulfapyridine were synthesized. The structures of these compounds were confirmed by elemental analysis, IR, 1H NMR and mass spectral data. All the newly synthesized compounds were evaluated for their in vitro cytotoxicity against liver and breast cancer cell line (HEPG2 and MCF7). Most of the screened compounds showed interesting cytotoxic activities compared with the used reference drug (doxorubicin). The radiosensitizing ability of some of the synthesized compounds was studied and the results showed an increase in the cell killing effect of γ-radiation after combination with the tested compounds.  相似文献   

18.
A mesomeric form of quaternary indoloquinazoline alkaloid, soyauxinium chloride (1) was obtained through the chemical investigation of stem bark and roots of Araliopsis soyauxii Engl. [syn. Vepris soyauxii (Engl.) Mziray] (Rutaceae) together with fifteen known compounds, including three furoquinoline alkaloids, three 2-quinolones, two limonoids, two triterpenes, two steroids, a coumarin, an acridone alkaloid, and a flavonoid glycoside. Their structures were established by comprehensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-HR-MS) and by comparison with previously reported data. 13C NMR data of araliopsinine are also reported here for the first time. The isolated compounds were screened in vitro for their effects on the viability of two different human cancer cell lines, namely prostate PC-3 adenocarcinoma cells and colorectal HT-29 adenocarcinoma cells. However, none of the tested compounds exhibited strong anti-proliferative or cytotoxic activities, to either prostate PC-3 cells or colon HT-29 cells. At 100 μM, the furoquinoline maculine showed a slightly increased anti-proliferative effect, however, exclusively on HT-29 cells. The chemotaxonomic significance of the isolated compounds has also been discussed.  相似文献   

19.
In the Yucatan Peninsula coast, a large diversity of seaweed species are found, and recent studies have reported the presence of metabolites with pharmaceutical importance. In this study, a biological screening of brown seaweed extracts from Dictyota ciliolata, Padina sanctae-crucis, Sargassum fluitans, and Turbinaria tricostata was carried out. Their cytotoxicity and antiproliferative activities were evaluated by the sulforhodamine B assay on human embryonic kidney (HEK 293), human breast cancer (MCF-7), human prostate cancer (LNCaP), and human hepatic cancer (Hep-G2) cell lines. Seaweed extracts were also tested for their anti-trichomonal (Trichomonas vaginalis) and anti-giardicidal (Giardia lamblia) properties. Fucan fractions were extracted using successive maceration with ethanol/water and freeze-dried. Organics extracts were obtained from ethanol residue from liquid–liquid fractionation. A total of four ethanol extracts, four fucan-rich fractions, four ethanolic extracts, and 12 organic fractions were obtained. Only the ethanolic extracts from Turbinaria tricostata and D. ciliolata were active against LNCaP (CC50 of 24.4 and 29.3 μg mL?1, respectively). Interestingly, the activity found in the extracts from D. ciliolata and Turbinaria tricostata was maintained when both extracts were subjected to a liquid–liquid fractionation with hexane on the LNCaP cell line (CC50 of 24.4 and 25.2 μg mL?1, respectively). The antiproliferative assays showed that both dichloromethane and ethanolic fractions from P. sanctae-crucis were active against MCF-7, with IC50 of 26.1 and 29.8 μg mL?1, respectively. These species have been selected for further bio-guided fractionation and isolation of active compounds.  相似文献   

20.

Key message

A multi-parallel approach gauging the mass spectrometry-based metabolite fingerprinting coupled with bioactivity and pathway evaluations could serve as an efficacious tool for inferring plant taxonomic orders.

Abstract

Thirty-four species from three plant families, namely Cornaceae (7), Fabaceae (9), and Rosaceae (18) were subjected to metabolite profiling using gas chromatography–time-of-flight-mass spectrometry (GC–TOF-MS) and ultrahigh performance liquid chromatography–linear trap quadrupole-ion trap-mass spectrometry (UHPLC–LTQ-IT-MS/MS), followed by multivariate analyses to determine the metabolites characteristic of these families. The partial least squares discriminant analysis (PLS-DA) revealed the distinct clustering pattern of metabolites for each family. The pathway analysis further highlighted the relatively higher proportions of flavonols and ellagitannins in the Cornaceae family than in the other two families. Higher levels of phenolic acids and flavan-3-ols were observed among species from the Rosaceae family, while amino acids, flavones, and isoflavones were more abundant among the Fabaceae family members. The antioxidant activities of plant extracts were measured using ABTS, DPPH, and FRAP assays, and indicated that extracts from the Rosaceae family had the highest activity, followed by those from Cornaceae and Fabaceae. The correlation map analysis positively links the proportional concentration of metabolites with their relative antioxidant activities, particularly in Cornaceae and Rosaceae. This work highlights the pre-eminence of the multi-parallel approach involving metabolite profiling and bioactivity evaluations coupled with metabolic pathways as an efficient methodology for the evaluation of plant phylogenies.
  相似文献   

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