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1.
Phytochemical investigation of Gentianella turkestanorum (Gentianaceae) afforded nineteen compounds, including six xanthones (1–6), two triterpenoids (7–8), eight flavones (9–16) and three iridoids (17–19). Here, we firstly reported that 1-hydroxy-3,5-dimethoxyxanthone (4), 1, 8-dihydroxy-3-methoxyxanthone (5), apigenin (9), quercetin (10), luteolin-7-O-glucoside (12) and three other compounds (1, 8-dihydroxy-3-methoxyxanthone (5), apigenin-7-O-gluco (1″ → 3‴) glucoside (15) and luteolin-7-O-gluco (1″ → 3‴) glucoside (16)) could be isolated from G. turkestanorum. The occurrence of chemical data and the sequence data might be employed as common constituents of the genera Gentianella, Lomatogonium and Swertia.  相似文献   

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Background and Aims: Species of Araceae accumulate calcium oxalate in the form ofcharacteristically grooved needle-shaped raphide crystals andmulti-crystal druses. This study focuses on the distributionand development of raphides and druses during leaf growth inten species of Amorphophallus (Araceae) in order to determinethe crystal macropatterns and the underlying ultrastructuralfeatures associated with formation of the unusual raphide groove. Methods: Transmission electron microscopy (TEM), scanning electron microscopy(SEM) and both bright-field and polarized-light microscopy wereused to study a range of developmental stages. Key Results: Raphide crystals are initiated very early in plant development.They are consistently present in most species and have a fairlyuniform distribution within mature tissues. Individual raphidesmay be formed by calcium oxalate deposition within individualcrystal chambers in the vacuole of an idioblast. Druse crystalsform later in the true leaves, and are absent from some species.Distribution of druses within leaves is more variable. Drusesinitially develop at leaf tips and then increase basipetallyas the leaf ages. Druse development may also be initiated incrystal chambers. Conclusions: The unusual grooved raphides in Amorphophallus species probablyresult from an unusual crystal chamber morphology. There aremultiple systems of transport and biomineralization of calciuminto the vacuole of the idioblast. Differences between raphideand druse idioblasts indicate different levels of cellular regulation.The relatively early development of raphides provides a defensivefunction in soft, growing tissues, and restricts build-up ofdangerously high levels of calcium in tissues that lack theability to adequately regulate calcium. The later developmentof druses could be primarily for calcium sequestration.  相似文献   

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Phytochemical investigation of Murraya tetramera C. C. Huang led to the isolation of ten flavonoids (1−10) and three anthraquinones (11−13). Their structures were determined on the basis of MS, NMR, specific optical rotation, and CD spectroscopic data analysis, and by comparison of the obtained data with those reported in the literature. This is the first report for the occurrence of compounds 2, 47, and 1113 in the Murraya species, and all the compounds were isolated from M. tetramera for the first time with the exception of compound 3. The chemotaxonomic significance of these compounds was also discussed.  相似文献   

6.
An outstanding flagship species in the plant kingdom is the Titan arum ( Amorphophallus titanum ), which produces a fountain-like bloom up to 3 m high. The unique appearance of three simultaneous inflorescences in May 2006 was a chance to analyse the flowering behaviour and thermogenesis of this giant. For the first time, the heating of the central column (spadix) could be documented using a high-performance thermographic camera. Time series analyses of the infrared image sequences revealed that the 3-m high spadix surface heats up in pulses emanating from the base of the inflorescence. The surface temperature reaches over 36 °C, compared to the ambient temperature of 27 °C. Waves of the carrion-like odour are synchronised with these heat pulses. The combination of heat pulses, the fountain-like shape plus the enormous size lead to a unique type of 'convection flower'. On the basis of our observations, we assume that Amorphophallus titanum is able to overcome thermodynamic decoupling by a self-produced convective process.  相似文献   

7.
Knema elegans, a tropical evergreen plant, belongs to Myristicaceae family. Phytochemical investigation on the leaves and twigs of K. elegans led to the isolation and identification of two new flavonoids knemavones A and B (1 and 2), along with fifteen known analogues (317). These compounds belong to four subtypes of flavonoids, including chalcones, flavanes, flavones, and isoflavones. The structures of 1 and 2 were elucidated by means of spectroscopic techniques, including HRESIMS, 1D, and 2D NMR experiments. Compounds 317 are isolated from the title plant for the first time. Moreover, the new chalcones 1 and 2 could serve as chemotaxonomic markers of K. elegans.  相似文献   

8.
Phytochemical study on the roots of Sophora tonkinensis Gagnep. led to the isolation of fifteen compounds, including eleven flavonoids (111) and four phenolic acids (1215). The structures of these compounds were elucidated based on NMR and HR-ESIMS analysis, further supported by comparison with previous literatures. Among them, compounds 2, 3, 4, 6, 9, 12 and 13 were firstly discovered from S. tonkinensis, compound 8 was firstly discovered from the genus Sophora. Furthermore, the chemotaxonomic significance of the obtained compounds was discussed in detail.  相似文献   

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The fresh leaves of Hillebrandia sandwicensis and 126 Begonia taxa were chemotaxonomically surveyed for flavonoids. Of their taxa, H. sandwicensis and 119 species, one variety and three hybrids were analyzed for flavonoids for the first time. Ten flavonols and eleven C-glycosylflavones were isolated and characterized as quercetin 3-O-rutinoside (1), kaempferol 3-O-rutinoside (2), isorhamnetin 3-O-rutinoside (3), quercetin 3-O-glucoside (4), quercetin 3-methyl ether 7-O-rhamnosylglucoside (5), quercetin 3,3'-dimethyl ether 7-O-rhamnosylglucoside (6), quercetin glycoside (13), quercetin glycoside (acylated) (14), kaempferol glycoside (17) and quercetin 3-O-rhamnoside (18) as flavonols, and isovitexin (7), vitexin (8), isoorientin (9), orientin (10), luteolin 6-C-pentoside (11), luteolin 8-C-pentoside (12), schaftoside (15), isoschaftoside (16), chrysoeriol 6,8-di-C-pentoside (19), apigenin 6,8-di-C-arabinoside (20) and isovitexin 2''-O-glucoside (21) as C-glycosylflavones. Quercetin 3-O-rutinoside (1) alone was isolated from H. sandwicensis endemic to Hawaii. Major flavonoids of almost Begonia species was also 1. Begonia species were divided into two chemotypes, i.e. flavonol containing type and C-glycosylflavone containing type. Of 14 section of the Begonia, almost species of many section, i.e. sect. Augustia, Coelocentrum, Doratometra, Leprosae, Loasibegonia, Monopteron and Ruizoperonia, were flavonol types. On the other hand, C-glycosyflavone type was comparatively most in sect. Platycentrum.  相似文献   

11.
Five flavonols, four flavones and one C-glycosylflavone were isolated from the leaves of Cathcartia villosa which is growing in the Himalayan Mountains. They were characterized as quercetin 3-O-vicianoside (1), quercetin 7,4′-di-O-glucoside (3), quercetin 3-O-rutinoside (4), quercetin 3-O-glucoside (5), quercetin 3-O-arabinosylarabinosylglucoside (6) (flavonols), luteolin (7), luteolin 7-O-glucoside (8), apigenin (9), chrysoeriol (10) (flavones), and vicenin-2 (11) (C-glycosylflavone) by UV, LC-MS, acid hydrolysis, NMR and/or HPLC and TLC comparisons with authentic samples. On the other hand, two flavonols 1 and kaempferol 3-O-vicianoside (2) were isolated and identified from the flowers of the species. Flavonoids were reported from the genus Cathcartia in this survey for the first time. Their chemical characters were chemotaxonomically compared with those of related Papaveraceous genera, Meconopsis and Papaver.  相似文献   

12.
BACKGROUND AND AIMS: Petioles of huge solitary leaves of mature plants of Amorphophallus resemble tree trunks supporting an umbrella-like crown. Since they may be 4 m tall, adaptations to water transport in the petioles are as important as adaptations to mechanical support of lamina. The petiole is a cylindrical shell composed of compact unlignified tissue with a honeycomb aerenchymatous core. In both parts numerous vascular bundles occur, which are unique because of the scarcity of lignified elements. In the xylemic part of each bundle there is a characteristic canal with unlignified walls. The xylem pecularities are described and interpreted. MATERIAL: Vascular bundles in mature petioles of Amorphophallus titanum and A. gigas plants were studied using light and scanning electron microscopy. KEY RESULTS: The xylemic canal represents a file of huge metaxylem tracheids (diameter 55-200 microm, length >30 mm) with unlignified lateral walls surrounded by turgid parenchyma cells. Only their end walls, orientated steeply, have lignified secondary thickenings. The file is accompanied by a strand of narrow tracheids with lignified bar-type secondary walls, which come into direct contact with the wide tracheid in many places along its length. CONCLUSIONS: The metaxylem tracheids in A. petioles are probably the longest and widest tracheids known. Only their end walls have lignified secondary thickenings. Tracheids are long due to enormous intercalary elongation and wide due to a transverse growth mechanism similar to that underlying formation of aerenchyma cavities. The lack of lignin in lateral walls shifts the function of 'pipe walls' to the turgid parenchyma paving the tracheid. The analogy to carinal canals of Equisetum, as well as other protoxylem lacunas is discussed. The stiff partitions between the long and wide tracheids are interpreted as structures similar to the end walls in vessels.  相似文献   

13.
Amorphophallus paeoniifolius is an herbaceous perennial tuber crop distributed widely in many Asian countries. We isolated 19 polymorphic loci from A. paeoniifolius using a dual‐suppression‐PCR technique. These loci provide microsatellite markers with high polymorphism ranging from three to 24 alleles per locus. The observed and expected heterozygosities ranged from 0.521 to 0.854 and from 0.766 to 0.930, respectively. This high allelic diversity indicates that our markers are suitable for a population study in A. paeoniifolius.  相似文献   

14.
A phytochemical study of chloroform-methanol and methanol extracts of Joannesia princeps Vell. Leaves led to the isolation of twenty eight compounds, including two α-ionones (2, 5), three glycosylated monoterpenes (1, 3, 4), eight phenolic compounds (6, 8, 9, 12, 14, 17, 18, 24), two gallotannins (10, 11), twelve flavonoids (7, 15, 16, 19, 2023, 2528), and one lignan (13). The structural characterization of the isolated compounds was performed by spectroscopic data and comparison with the literature. All compounds were isolated from this species and from the genus Joannesia for the first time. The chemotaxonomic importance of these metabolites is therefore summarized.  相似文献   

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16.
During the second blooming of a cultivated Amorphophallus gigas Teijsm and Binnend in the Botanical Gardens of the University of Tokyo, the surface temperature of the inflorescence was measured using an infrared camera. Contrary to studies of other species in the genus Amorphophallus, the surface of the inflorescence showed only very faint thermogenesis and had a lower temperature than that of the background. This cooling effect appeared to be due to a loss of heat through evaporation, which was caused by the secretion of a very large amount of odorous liquid. Chemical analysis revealed that the major components of this liquid were acetic acid, propionic acid, butyric acid and valeric acids. The composition of the odorous liquid was slightly different between the spathe surface and the sterile appendix. The major component(s) of the odorous material from the spathe was butyric acid, and from the sterile appendix was valeric acids. These components would play dual roles of adding the characteristic smell to the inflorescence and cooling the inflorescence.  相似文献   

17.
国产芋属花粉形态   总被引:4,自引:1,他引:3  
通过光镜和扫描电子显微镜观察了芋属(Colocasia Schott)6种、1变种、1品种的花粉形态,其中贡山芋C.gaoligongensis,龚氏芋C.gongii,李氏香芋C.lihengiae,花叶芋C.bic-olor4个种为首次报道。本属花粉为圆球形,无萌发孔。外壁纹饰分为两类:大野芋C.giga-ntea外壁光滑无刺,其余各种均具刺。花粉大小为20.07—32.76μm。  相似文献   

18.
Camarea is a South-American endemic genus comprising eight species. In the present work leaf flavonoids of seven species of Camarea were identified, aiming to evaluate the usefulness of their distribution as a taxonomic aid. A total of 12 flavonoids were isolated and identified. Free aglycones, such as apigenin, chrysoeriol, kaempferol and quercetin, as well as 7-O-glycosides of apigenin and luteolin, 3-O-glycosides of kaempferol and quercetin were identified. Flavonoid distribution in Camarea species, taking into account aglycones and aglycone moieties of glycosides, was used to obtain a phenogram of chemical affinities. Apigenin, chrysoeriol and kaempferol were the main discriminating characters for links establishment. The resultant tree suggests the links: 1) Camarea hirsuta, Camarea affinis and C. affinis × C. hirsuta; 2) Camarea elongata and Camarea axillaris; 3) Camarea sericea and Camarea humifusa. The results are in agreement with morphological similarities and disagree with several points of n-alkane evidence. The results support the recognition of Camarea triphylla as synonymy of C. axillaris.  相似文献   

19.
Phytochemical investigation of Litsea fruticosa (Hemsl.) Gamble resulted in the isolation of eight flavonoids and four alkaloids. Their structures were identified as pinostrobin, pinocembrin, pinocembrin chalcone, apigenin, kaempferol, astragalin, isoquercetin, kaempferol 3,4′-di-O-l-rhamnopyranoside, boldine, laurolitsine, actinodaphnine and ushinsunine by comparison of their spectral data with those reported previously in the literature. Chemotaxonomic significance of these investigation is summarized.  相似文献   

20.
Typhonium muaklekense D. Sookchaloem & S. Maneeanakekul is described and illustrated. This new species resembles T. roxburghii Schott and T. varians Hett. & Sookch. in the spathe. Drawings, photographs and a table comparing diagnostic features of T. muaklekense, T. roxburghii and T. varians are provided.  相似文献   

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