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Bark, wood and leaves of Ocotea catharinensis contain respectively 10 (average yield 0.7%.), 15 (average yield 0.004%.) and one (yield 0.4%.) neolignans of the bicyclo[3.2.1]octanoid and the hydrobenzofuranoid structural types, including the new rel-(7S,8R,1′R,4′S,5′R,6′R)-Δ8′-4′,6′-dihydroxy-5′-methoxy-3,4-methylenedioxy-3′-oxo-8.1′,7.5′-neolignan, (7S,8S)-Δ1′,3′,5′,8′-5,3′,5′-trimethoxy-3,4-methylenedioxy-8.1′,7.O.6′,4.O.7′-neolignan, (7R,8S,1′R,3′R)-Δ5′,8′-3,4,3′,5′-tetramethoxy-4′-oxo-8.1′,7.O.6′-neolignan and rel-(7R,8S,1′R,2′S)-Δ4′,8′-2′-hydroxy-3,4-dimethoxy-3′-oxo-8.1′,7.O.2′-neolignan.  相似文献   

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Chemical variability in populations of Cryptocarya mandioccana Meisner was investigated using chromatographic profiles of flavonoid glycosides and styrylpyrones from leaves of 57 trees from three sites in the Atlantic rain forest of São Paulo State – Brazil. The flavonoid profiles of the leaves from all trees were similar. However, four chemotypes were recognized by qualitative and quantitative differences in styrylpyrones. Chemotype F showed lower contents of these polyketides than chemotypes FS1, FS2 and FS3, which were characterized by styrylpyrones formed from different numbers of acetate units. Chemotypes with higher levels of styrylpyrones were more frequent in southern regions, with soils of higher K+, Ca2+ and Mg2+ content. Soil and climate could indicate a genetic or environmental influence on styrylpyrones in leaves of C. mandioccana.  相似文献   

5.
为了解大叶桃花心木(Swietenia macrophylla)树皮的化学成分,采用硅胶、凝胶、制备液相等手段分离、纯化,从其树皮提取物中分离得到9个化合物。根据理化性质及波谱数据,鉴定化合物结构分别为香草酸(1)、东莨菪素(2)、大黄素甲醚(3)、3,4,5-三甲氧基苯基-β-D-吡喃葡萄糖苷(4)、(+)-儿茶素(5)、5′-甲氧基异落叶松脂素-9′-O-β-D-吡喃木糖苷(6)、南烛木树脂酚-9′-O-β-D-吡喃木糖苷(7)、豆甾醇(8)、豆甾醇-3-O-β-D-吡喃葡萄糖苷(9)。除化合物5外,其余化合物为首次从该植物中分离。细胞毒活性试验表明化合物均无显著的细胞毒活性。  相似文献   

6.
The leaf essential oils of 10 species of Ocotea (Lauraceae) from Monteverde, Costa Rica (Ocotea floribunda, Ocotea holdridgeana, Ocotea meziana, Ocotea sinuata, Ocotea tonduzii, Ocotea valeriana, Ocotea veraguensis, Ocotea whitei, and two undescribed species, Ocotea new species “los llanos”, and Ocotea new species “small leaf”) have been obtained by hydrodistillation and analyzed by GC–MS in order to discern the differences and similarities between the volatile chemical compositions of these species. The principal common constituents of the 10 species of Ocotea were α-pinene, β-pinene, β-caryophyllene, and germacrene-D.  相似文献   

7.
A new chromene, cumanensic acid (1), together with eight known compounds have been isolated from the aerial part of Piper cf. cumanense Kunth (Piperaceae). Chromene structure was identified on the basis of spectroscopic analysis and comparison with literature data. The compound showed antifungal activity against Fusarium oxysporum f. sp. dianthi and Botrytis cinerea.  相似文献   

8.
岑文  孔维维  郑鹏  化文平 《广西植物》2015,35(5):755-760
龙胆苦苷(gentiopicroside)等裂环烯醚萜苷类化合物是中药秦艽中主要的有效成分,属于萜类化合物的衍生物,1-羟基-2-甲基-2-(E)-丁烯基-4-焦磷酸还原酶(1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase,HDR)是植物萜类物质合成的关键酶之一。该研究在实验室高通量测序的基础上,采用RT-PCR方法克隆了秦艽HDR基因(即Gm HDR基因),利用生物信息学的方法分析了Gm HDR编码氨基酸序列的理化性质、信号肽、转运肽、亚细胞定位、保守结构域和高级结构等特征,并采用实时定量PCR分析了HDR的表达模式。结果表明:秦艽Gm HDR基因包含一个完整的长1 392 bp的ORF框,编码463个氨基酸;Gm HDR与萝芙木、艾菊等植物HDR蛋白具有很高的一致性(≥84%),无跨膜结构域,有叶绿体转运肽等结构,主要定位于叶绿体中。实时定量PCR结果显示,Gm HDR基因在秦艽的花中进行表达量高,在叶、茎和根等部位表达较低。Gm HDR在序列上与其他植物的HDR蛋白序列特征上存在很大的相似性;Gm HDR基因主要在秦艽花中表达,可能主要参与花中萜类物质的合成。该研究结果可为今后研究秦艽环烯醚萜类化合物的生物合成机制提供依据。  相似文献   

9.
3-Hydroxybenzo[a]pyrene (3-OHB[a]P), one of the metabolites of benzo[a]pyrene (B[a]P), has been determined in human urine using an automated column-switching procedure. The hydrolysed biological sample is centrifuged just prior to being injected into a reusable precolumn loop, which is packed with a preparative phase and coupled on-line to a liquid chromatographic (LC) system. A rapid pre-treatment of the hydrolysed sample, consisting of a concentration and a crude clean-up, is performed on the precolumn. The analytes are then non-selectively desorbed with the LC eluent and the sample is cleaned again in three successive purification columns using the direct transfer or “heart-cut” technique. The pre-treatment does not exceed 3 min. and the entire analytical purification and separation procedure takes less than 30 min. Average 3-OHB[a]P recovery reaches 95% in the 1–50 ng/l range of urine, and the detection limit is 0.1 ng/l urine for a 3 ml injection of hydrolysed urine. The developed method was compared with a more time-consuming off-line method to analyse urines of B[a]P gavaged rats; the statistical treatment indicates that both methods are in agreement. The method was applied to purify and concentrate the urine samples of workers exposed and apparently unexposed to polycyclic aromatic hydrocarbons (PAHs).  相似文献   

10.
The composition of the essential oil from leaves of Cryptocarya mandioccana has been determined by chromatographic fractionation and GC–FID, GC–MS and 13C NMR analyses, yielding the identification of 64 compounds with predominance of isomeric sesquiterpenes with molecular weights of 204. The main components of the oil obtained by hydrodistillation were β-caryophyllene, spathulenol, caryophyllene oxide, δ-cadinene, germacrene D, benzaldehyde and bicyclogermacrene. However, the oil obtained by steam distillation contained higher levels of sesquiterpene hydrocarbons, with predominance of β-caryophyllene (C), germacrene D (G) and bicyclogermacrene (B), and was considered to be more representative of the composition of the oil in its natural state. The intraspecific chemical variability of the essential oil obtained by steam distillation was evaluated within populations of trees growing at three separate locations in the state of São Paulo, Brazil. Three distinct chemical groups could be characterised due to differences in the relative percentages of the three main sesquiterpenes from essential oil: CGB [relative contents of C (14–34%), G (5–28%), B (8–15%)], BCG [B (17–34%), C (9–24%), G (12–25%)] and GCB [G (22–42%), C (4–17%), B (7–15%)]. Individuals from groups CGB and BCG were found to be more frequent at south locations while group GCB is predominant in north location.  相似文献   

11.
报道了中国菊科一新归化植物——白花金钮扣[Acmella radicans var. debilis (Kunth) R. K. Jansen],并提供了该变种详细的特征描述和彩色照片。该变种原产南美洲和西印度群岛,最近在我国安徽黟县发现一归化居群。野外调查发现,该植物在黟县生长旺盛,成熟时种子结实量大,表现出一定的入侵性。  相似文献   

12.
该文报道了在云南省马关县古林箐省级自然保护区发现的一个云南省新记录种——皱皮油丹(Alseodaphne rugosa Merr.et Chun),并对其形态、生境及该新记录种的生物地理学意义进行了描述与讨论。此新记录种的发现对樟科油丹属植物的系统分类学、生物地理学和区域生物多样性等方面的研究具有重要意义,同时也为探讨海南岛的起源问题提供了具有价值的研究材料。  相似文献   

13.
The phospholipid requirement of the (Ca2+ + Mg2+)-ATPase present in a membrane fraction from human platelets was studied using various purified phospholipases. Only those phospholipases, which hydrolyse the negatively charged phospholipids, inhibited the (Ca2+ + Mg2+)-ATPase activity. The ATPase activity could be restored by adding mixed micelles of Triton X-100 and phosphatidylserine or phosphatidylinositol. Micelles with phosphatidic acid, phosphatidylcholine, phosphatidylethanolamine or sphingomyelin could not be used for reconstitution and inhibited the activity of the native enzyme.  相似文献   

14.
The reaction of 2-(2-aminophenyl)benzothiazole (Habt) with [Re(CO)5Br] led to the isolation of the rhenium(I) complex fac-[Re(Habt)(CO)3Br] (1). With trans-[ReOCl3(PPh3)2], the ligand Habt decomposed to form the oxofree rhenium(V) complex [Re(itp)2Cl(PPh3)] (2) (itp = 2-amidophenylthiolate). From the reaction of trans-[ReOBr3(PPh3)2] with 2-(2-hydroxyphenyl)benzothiazole (Hhpd) the complex [ReVOBr2(hpd)(PPh3)] (3) was obtained. Complexes 1-3 are stable and lipophilic. 1H NMR and infrared assignments, as well as the X-ray crystal structures, of the complexes are reported.  相似文献   

15.
Tetradenia riparia (Lamiaceae) is a well-known herbal medicine with a variety of useful properties, including its acaricidal effect. This experiment was carried out to study the bioacaricidal activity of T. riparia essential oil (EO) against engorged females of Rhipicephalus (Boophilus) microplus (Acari; Ixodidae). For this purpose, nine serial concentrations (12.50%, 6.25%, 3.75%, 1.80%, 0.90%, 0.45%, 0.22%, 0.11%, and 0.056% w/v) of T. riparia were used for the adult immersion test (AIT). For the larval packet test (LPT), we used 14 serial concentrations (100.00%, 50.00%, 25.00%, 12.50%, 6.25%, 3.65%, 1.82%, 0.91%, 0.45%, 0.228%, 0.114%, 0.057%, 0.028%, and 0.014% w/v). The results for AIT showed 100.00% and 2.05% mortality, 19.00 and 90.20% for the total number of eggs, egg-laying inhibition of 0.00% and 90.20%, hatchability inhibition of 0.00% and 70.23%, and product effectiveness of 100.00% and 2.89%, respectively. The AIT indicated that the LC50 and LC99.9, calculated using the Probit test, were for mortality (%) 0.534 g/mL (0.436–0.632) and 1.552 g/mL (1.183–1.92); for total number of eggs were 0.449 g/mL (0.339–0.558) and 1.76 g/mL (1.27–2.248); and for hatchability inhibition were 0.114 g/mL (0.0–0.31) and 2.462 g/mL (1.501–3.422), respectively. Larvae between 14 and 21 days old were fasted and placed in each envelope. Bioassays were performed at 27° ± 1 °C, RH ? 80%. Larval mortality was observed 24 h after treatment and showed 10.60–100% mortality in the LPT bioassay. The LPT showed that the LC50 and LC99.9 were 1.222 g/mL (0.655–1.788) and 11.382 g/mL (7.84–14.91), respectively. A positive correlation between T. riparia EO concentration and tick control, was observed by the strong acaricidal effects against R. (B.) microplus, and the mortality rate of ticks was dose-dependent. Our results showed that T. riparia is a promising candidate as an acaricide against resistant strains of R. (B.) microplus.  相似文献   

16.
Systematic studies of Ceratitis (Tephritidae) fruit flies using molecular (i.e., COI, ND6, and period genes) and morphological (plus host-use characters) data have recently challenged the monophyly of the subgenera Ceratitis (Ceratitis) and Ceratitis (Pterandrus). In this paper, we report on the phylogenetic utility of three single-copy nuclear gene regions (two non-overlapping fragments of the carbamoylphosphate synthetase, CPS, locus of CAD, and a fragment of tango) within these taxa and investigate evolutionary relationships based on a concatenated ca. 3.4 kb data set that includes the six protein encoding gene regions. Results indicate that the CAD and tango genes provide useful phylogenetic signal within the taxa and are compatible with the previously studied genes. The two subgenera, as currently classified, are not monophyletic. Our molecular phylogenetic analyses support a revised classification in which (1) the subgenus C. (Pterandrus) comprises two lineages called A and B, (2) the C. (Pterandrus) B species should be included in C. (Ceratitis), and (3) the newly defined subgenera C. (Pterandrus) (=Pterandrus section A) and C. (Ceratitis) [=C. (Ceratitis) + C. (Pterandrus) section B] are reciprocally monophyletic.  相似文献   

17.
In a previous study, it was demonstrated that N-(phenethyl)succinamic acid (PESA) derivatives form a new category of root-promoting substances which do not exhibit auxin-like activities, such as stem elongation and leaf epinasty (Soejima et al., 2000 [Plant Cell Physiol. 41s: 197]). In this study, N-[2-(3-indolyl)ethyl]succinamic acid (IESA) and N-[2-(1-naphthyl)ethyl]succinamic acid (NESA) were synthesized, and their biological activities were evaluated. In an adzuki root-promoting assay, IESA and NESA exhibited root-promoting activity equivalent to PESA. In adzuki stem elongation assays, elongation activity was not observed in the stem segments soaked in either an IESA or NESA aqueous solution, whereas the stem segments immersed in Indole-3-acetic acid (IAA) or 1-naphthylacetic acid (NAA) aqueous solution were clearly elongated. In an epinastic bending study, IAA and NAA exhibited leaf epinasty, whereas IESA and NESA did not, suggesting that the IESA and NESA derivatives belong to the same category of root-promoting substances as PESA derivatives and are different from auxin-like substances. In addition, eleven kinds of IESA derivatives and nineteen kinds of NESA derivatives were synthesized, and their root-promoting activities were measured. The activities of methyl ester derivatives were approximately three times higher than that of the acid compounds, with exceptions for some compounds. The partition coefficient (P) between 1-octanol and water for each IESA, NESA, and PESA derivative was measured in order to evaluate the hydrophobicity of their molecules and to determine their structure–activity relationship. The results indicate that the root-promoting activity of the acid compounds was significantly correlated with their hydrophobicity, whereas that of ester derivatives was not correlated.  相似文献   

18.
Among chemicals that are widely spread both in terrestrial and aquatic ecosystems, benzo[a]pyrene is a major source of concern. However, little is known about its adverse effects on plants, as well as about the role of mycorrhization in protection of plant grown in benzo[a]pyrene-polluted conditions. Hence, to contribute to a better understanding of the adverse effects of polycyclic aromatic hydrocarbons on the partners of mycorrhizal symbiotic association, benzo[a]pyrene-induced oxidative stress was studied in transformed Cichorium intybus roots grown in vitro and colonized or not by Glomus intraradices. The arbuscular mycorrhizal fungus development (colonization, extraradical hyphae length, and spore formation) was significantly reduced in response to increasing concentrations of benzo[a]pyrene (35–280 μM). The higher length of arbuscular mycorrhizal roots, compared to non-arbuscular mycorrhizal roots following benzo[a]pyrene exposure, pointed out a lower toxicity of benzo[a]pyrene in arbuscular mycorrhizal roots, thereby suggesting protection of the roots by mycorrhization. Accordingly, in benzo[a]pyrene-exposed arbuscular mycorrhizal roots, statistically significant decreases were observed in malondialdehyde concentration and 8-hydroxy-2′-desoxyguanosine formation. The higher superoxide dismutase activity detected in mycorrhizal chicory roots could explain the benzo[a]pyrene tolerance of the colonized roots. Taken together, these results support an essential role of mycorrhizal fungi in protecting plants submitted to polycyclic aromatic hydrocarbon, notably by reducing polycyclic aromatic hydrocarbon-induced oxidative stress damage.  相似文献   

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Two high-molecular water-soluble preparations with high anticomplementary and antioxidant activity were isolated from the roots of Symphytum asperum and S. caucasicum. Their main chemical constituent was found to be poly[oxy-1-carboxy-2-(3,4-dihydroxyphenyl)ethylene] according to IR and NMR spectroscopy.  相似文献   

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