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1.
Three new diarylheptanoids, together with ten known ones, were isolated from the ethanol extract from the rhizomes of Alpinia officinarum Hance. The structural identification of these compounds was mainly achieved by spectroscopic methods. The new compounds were elucidated as 7-(4″, 5″-dihydroxy-3″-methoxyphenyl)-1-phenyl -4-heptene-3-one (1), 1, 7-diphenyl-5-heptene-3-one (2) and 4-phenethyl-1, 7-diphenyl -1-heptene-3, 5-dione (3), respectively. All of the compounds showed antibacterial activity against Helicobactor pylori. Especially, the three new compounds showed strong antibacterial activity against Hp-Sydney strain 1 with the MIC values of 9–12 μg/mL, and against Hp-F44 with the MIC values of 25–30 μg/mL.  相似文献   

2.
A new withanolide identified by spectroscopic analysis as 12β-acetoxy-4-deoxy-5,6-deoxy-Δ5–withanolide D and Withanolide D, were isolated from the leaves of Acnistus arborescens. Cytotoxic activity of these two compounds against human tumor cell lines HT-29, MCF-7, MKN-45, HEp-2, HeLa, U-937 and two human normal fibroblast cultures, Fib04 and Fib05, were assessed. Withanolide D presented in vitro cytotoxic activity against tumor cell lines at the low micromolar range (LC50:1.0 to 1.69 µM) and showed a slightly lower activity against Fib04, suggesting moderated selectivity among tumoral and normal cells. No cytotoxic effect was observed for 12β-acetoxy-4-deoxy-5,6-deoxy-Δ5–withanolide D.  相似文献   

3.
Phytochemical investigation of the stem bark of Trewia nudiflora led to the isolation of two new cardenolides, trewianin (1) and trewioside (2), along with scopoletin (3) and indole-3-carboxylic acid (4). Structures were established by 1D- and 2D NMR spectroscopy, HR-MS analysis, and by comparison with literature data.  相似文献   

4.
Six flavonol glycosides, compounds 1-3 from A. burnatii Gáyer and 4-6 from A. variegatum L., were obtained from their methanol extracts of aerial parts. The identified structures were quercetin 3-O-β-d-glucopyranoside-7-O-(6-E-p-coumaroyl)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (1), quercetin 3-O-β-d-glucopyranoside-7-O-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (2), quercetin 3-O-β-d-glucopyranoside-7-O-(6-E-caffeoyl)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (3), kaempferol 3-O-β-d-galactopyranoside-7-O-α-l-arabinopyranoside (4), quercetin 3-O-β-d-glucopyranoside (5), and kaempferol 3-O-β-d-glucopyranoside (6). Compounds 1, 2 and 4 were isolated for the first time. The antioxidant potential of the methanol extracts and pure compounds was tested with different assays.  相似文献   

5.
Phytochemical investigation of Laureliopsis philippiana resulted in isolation of a new bisbenzylisoquinoline alkaloid (1) named laureliopsine A. The structure was established by spectroscopic methods, including 2D homo- and heteronuclear NMR experiments. This finding of a bisbenzylisoquinoline alkaloid in Laureliopsis supports its close relationship to Atherosperma and its taxonomic segregation from Laurelia.  相似文献   

6.
采用Wolbachia的通用引物、A大组和B大组的特异性引物对一种新的白蜡虫寄生蜂--长尾啮小蜂(Aprostocetus sp.)体内Wolbachia的wsp基因进行分子检测,所获得的基因片段分别命名为wApr、wAprB和wAprB,长度分别为620、566和463bp;基因序列分析表明:wApA、wAprB与w...  相似文献   

7.
Two new triterpene glycosides named ilexpublesnin A (1) and ilexpublesnin B (2) were isolated from the root of Ilex pubescens. Their structures were determined as 3-O-(β-d-xylopyranosyl)-28-O-(β-d-glucopyranosyl)-3β, 19α-dihydroxyurs-23-oxo-12-en-28-oic acid (1) and 28-O-(β-d-xylopyranosyl-(2 → 1)-β-d-glucopyranosyl)-3β, 19α-dihydroxyurs-23-oxo-12-en-28-oic acid (2) on the basis of chemical and spectroscopic methods.  相似文献   

8.
Efforts in Europe to convert Norway spruce (Picea abies) plantations to broadleaf or mixed broadleaf-conifer forests could be bolstered by an increased understanding of how artificial regeneration acclimates and functions under a range of Norway spruce stand conditions. We studied foliage characteristics and leaf-level photosynthesis on 7-year-old European beech (Fagus sylvatica) and pedunculate oak (Quercus robur) regeneration established in open patches and shelterwoods of a partially harvested Norway spruce plantation in southwestern Sweden. Both species exhibited morphological plasticity at the leaf level by developing leaf blades in patches with an average mass per unit area (LMA) 54% greater than of those in shelterwoods, and at the plant level by maintaining a leaf area ratio (LAR) in shelterwoods that was 78% greater than in patches. However, we observed interspecific differences in photosynthetic capacity relative to spruce canopy openness. Photosynthetic capacity (A1600, net photosynthesis at a photosynthetic photon flux density of 1600 μmol photons m−2 s−1) of beech in respect to the canopy gradient was best related to leaf mass, and declined substantially with increasing canopy openness primarily because leaf nitrogen (N) in this species decreased about 0.9 mg g−1 with each 10% rise in canopy openness. In contrast, A1600 of oak showed a weak response to mass-based N, and furthermore the percentage of N remained constant in oak leaf tissues across the canopy gradient. Therefore, oak photosynthetic capacity along the canopy gradient was best related to leaf area, and increased as the spruce canopy thinned primarily because LMA rose 8.6 g m−2 for each 10% increase in canopy openness. These findings support the premise that spruce stand structure regulates photosynthetic capacity of beech through processes that determine N status of this species; leaf N (mass basis) was greatest under relatively closed spruce canopies where leaves apparently acclimate by enhancing light harvesting mechanisms. Spruce stand structure regulates photosynthetic capacity of oak through processes that control LMA; LMA was greatest under open spruce canopies of high light availability where leaves apparently acclimate by enhancing CO2 fixation mechanisms.  相似文献   

9.
Three new triterpene saponins, leonticins I (1), J (2) and L (3) were isolated from the tubers of Leontice smirnowii. On the basis of spectroscopic methods, including 2D NMR experiments (DEPT, gs-COSY, gs-HMQC, gs-HMBC and gs-HSQC-TOCSY), mass spectrometry (HR-ESI-MS) and chemical degradation, the structures of the new compounds were elucidated as 3-O-β-D-glucopyranosyl-(1 → 3)-[β-D-xylopyranosyl-1 → 2)]-α-L-arabinopyranosyl-28-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]-3β-hydroxy-30-norolean-12,20(29)-dien-28-oic acid (1), 3-O-[β-D-xylopyranosyl-(1 → 3)-β-D-galactopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-arabinopyranosyl]-28-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]-3β-hydroxy-30-norolean-12,20(29)-dien-28-oic acid (2) and 3-O-[β-D-xylopyranosyl-(1 → 3)-β-D-galactopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)]-[β-D-xylopyranosyl-(1 → 2)]-α-L-arabinopyranosyl]-28-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]-3β-hydroxy-30-norolean-12,20(29)-dien-28-oic acid (3), respectively. The aglycone 3β-hydroxy-30-norolean-12,20(29)-dien-28-oic acid was observed for the first time in Leontice species.  相似文献   

10.
Six new anthraquinone glycosides: digiferruginol-1-methylether-11-O-β-gentiobioside (1); digiferruginol-11-O-β-primeveroside (2); damnacanthol-11-O-β-primeveroside (3); 1-methoxy-2-primeverosyloxymethyl-anthraquinone-3-olate (4); 1-hydroxy-2-primeverosyloxymethyl-anthraquinone-3-olate (5); and 1-hydroxy-5,6-dimethoxy-2-methyl-7-primeverosyloxyanthraquinone (6) were isolated from Morinda citrifolia (Rubiaceae) roots together with four known anthraquinone glycosides. The structures of the new compounds were established using spectral methods. For five of the new compounds, the sugar is attached via the hydroxymethyl group of the anthraquinone C-2 carbon. This type of bond is rarely found for anthraquinone glycosides isolated from natural sources.  相似文献   

11.
Sarcandracoumarin (1), the first coumarin having a 1-phenylethyl substituent at the C-3 position, was isolated along with eleven known phenolic compounds from the water extract of Sarcandra glabra. Its structure was elucidated on the basis of spectroscopic data. Compound 1 exhibited moderate or weak cytotoxicity against several tumor cell lines.  相似文献   

12.
Two new norlignan derivatives, crassifoside I (1) and sinensigenin C (2), were isolated from the rhizomes of Curculigo capitulate, along with six known norlignan derivatives, 1,1-bis(3,4-dihydroxyphenyl)-1-(2-furan)-methane (3), crassifogenin B (4), crassifoside A (5), breviscaside A (6), crassifoside D (7), and curcapital (8). Their structures were elucidated on the basis of spectral evidence and comparisons with literature data. The 1H and 13C NMR data of compound 3 was first assigned. Compounds 37 were isolated from this plant for the first time.  相似文献   

13.
Two new annonaceous acetogenins named as squamostanin-C and squamostanin-D were isolated from 95% EtOH extract of the seeds of Annona squamosa. Their structures were determined by spectroscopic method, and their cytotoxicities were evaluated by using MTT method.  相似文献   

14.
An N  Zou ZM  Tian Z  Luo XZ  Yang SL  Xu LZ 《Fitoterapia》2008,79(1):27-31
Two new diarylheptanoids (1, 2), together with two known analogs (3, 4), were isolated from the rhizomes of Alpinia officinarum. The new compounds were elucidated to be (5S)-5-hydroxy-7-(3, 4-dihydroxyphenyl)-1-phenyl-3-heptanone (1) and (5R)-5-hydroxy-7-(3-methoxy-4, 5-dihydroxyphenyl)-1-phenyl-3-heptanone (2) based on their spectral analysis. Compound 4 showed moderate cytotoxicity against human tumor cell lines, HepG2, MCF-7 and SF-268, while no significant effect were found for compounds 1-3.  相似文献   

15.
GAPDH is a typical structural protein in eukaryote organism, which plays an important role involved in the biosynthesis of cell composition and the expression of genetic information. In order to reveal the biological function of GAPDH in the growth and development of Eucalyptus, 3 genes were obtained and named as EC-GAP1, EC-GAP2 and EC-GAP3 by amplification with primers for GAPDH genes conserved regions and RACE method from the young leaf of Eucalyptus camaldulensis. The bioinformatics analysis suggested that the proteins encoded by corresponding genes owned the typical conserved domains of GAPDH and showed high homology with those of other plant species.  相似文献   

16.
[目的]克隆马尾松谷胱甘肽过氧化物酶基因,并对其进行功能研究。[方法]采用RACE技术克隆基因c DNA序列,实时荧光定量PCR检测基因在马尾松干旱胁迫下的表达模式,花序浸泡法转化拟南芥,并对转基因与野生型拟南芥的生长表型和根系生长进行分析。利用荧光显微镜技术对转基因拟南芥不定根进行GFP荧光检测。[结果]克隆到1个871 bp的GPX基因全长c DNA序列,命名为Pm GPX6。Pm GPX6包括513 bp的完整开放阅读框,编码170个氨基酸残基。Pm GPX6蛋白与油松Pt GPX蛋白同源性达95%。Pm GPX6在马尾松根中高表达,茎、叶中表达量低。在干旱胁迫下,Pm GPX6在根、茎、叶中的表达量均在第15天达到最大,随后出现下降趋势。过表达Pm GPX6与野生型拟南芥植株在正常水分条件下表型与根长差异不大,但在干旱胁迫下,转基因植株根系更长。转基因拟南芥根在蓝色光激发下能发出强烈的绿色荧光,表明Pm GPX6基因能高效表达。[结论]推测Pm GPX6可能参与马尾松干旱胁迫应答。  相似文献   

17.
龙丹竹新品种‘花龙丹’   总被引:1,自引:0,他引:1       下载免费PDF全文
2014年6月5日,国际竹类栽培品种登录中心组织有关专家对成都市望江楼公园进行实地考察时,发现一牡竹属(Dendrocalamus Nees)的花笋、花秆、花叶竹子,公园方技术人员称其为花龙丹竹。经进一步查证,得知该竹栽培居群是1960年3月8日从四川省邛崃市的野生居群引种而来。1988年,易同培教授将其定名为龙丹竹(Dendrocalamus rongchengensis Yi et C.Y.Sia),并在《竹子研究汇刊》上正式发表[1],模式标本存四川农业大  相似文献   

18.
以杜仲叶片cDNA为模板,采用反转录RCR及RACE技术分离出DXR基因cDNA全长。序列分析结果表明该基因序列全长1 814 bp,共编码478个氨基酸,推导的蛋白质分子量为51.71 kD,理论等电点5.79,命名为EuDXR。推导的EuDXR蛋白质序列具有植物DXR酶的5个典型基序,并预测出26个潜在的功能位点。系统进化树分析表明EuDXR蛋白与玉米、水稻亲缘关系最近,其次为橡胶、拟南芥、烟草。  相似文献   

19.
应用RT-PCR和RACE法从麻疯树总RNA中分离出pepc基因全长cDNA,长度为3 142 bp,阅读框2 898 bp,编码965个氨基酸,在GenBank中登录,序列号为EU069413。它的氨基酸序列与蓖麻、陆地棉、橙、大豆、花生、烟草、油菜、拟南芥的氨基酸同源性分别为94.94%、92.46%、90.60%、90.50%、90.50%、88.33%、84.61%、82.44%。该基因编码了pepc基因家族中的pepc1,蛋白属于C3型PEPC。推测了pepc编码蛋白分子量为110.6 kD,并对其稳定性、二级结构、疏水性等特性进行了分析,最后确定了该蛋白的功能位点和结构域。  相似文献   

20.
The bulbs of Ledebouria floribunda (Baker) Jessop have yielded two novel compounds, 7-O-[α-rhamnopyranosyl-(1→6)-β-glucopiranosyl]-5-hydroxy-3-(4-methoxybenzyl)-chroman-4-one (1) and 7-O-[α-rhamnopyranosyl-(1→6)-β-glucopiranosyl]-5-hydroxy-3-(4′-hydroxybenzyl)-chroman-4-one (2) along with five other known compounds, 5,7-dihydroxy-3-(4′-methoxybenzyl)-chroman-4-one or 3,9-dihidroeucomin (3), 5,7-dihidroxy-6-methoxy-3-(4′-methoxybenzyl)-chroman-4-one (4), 5,7-dihidroxy 3-(4′-hydroxybenzyl)-chroman-4-one or 4,4′-demethyl-3,9-dihydropuctatin (5), 5,7-dihidroxy-3-(4′-hydroxybenzyl)-6-methoxy-chroman-4-one or 3,9-dihydroeucomnalin (6) and 7-hydroxy-3-(4′-hydroxybenzyl)-5-methoxy-chroman-4-one (7). Their structures were elucidated by spectra analysis. The seven homoisoflavanones were found to be antioxidant against DPPH radical and β-carotene/linoleic acid system.  相似文献   

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