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1.
A survey of 26 species in 12 genera of the Portulacaceae showed the presence of flavonoids in 24, and their absence in two, Hectorella caespitosa Hooker fil. and Lyallia kerguelensis Hooker fil. Of the 24 positive species, 16 are reported for the first time. In all 24 however, flavonols and flavones did not occur together suggesting that this dichotomy might be useful for classification at and below the generic level in the Portulacaceae, e.g. the genera Silvaea Philippi (syn. Philippiamara Kuntze), Ceraria Pearson & Stephens and Portulacaria Jacquin which were previously grouped together on palynological characteristics have now been shown to differ in their leaf flavonoids, subsidiary cells of the stomata and geographical location: Silvaea possesses flavones and is endemic to South America, while Ceraria and Portulacaria possess flavonols and are endemic to Africa. The dichotomy also occurs below the generic level. In Calandrinia H.B.K. and Portulaca L. the dichotomy amongst their species is supported by other new taxonomic characters from cytology, palynology, pubescence of surfaces, type of subsidiary cells surrounding the leaf stomata and seed morphology recently elucidated by the author.  相似文献   

2.
A flavonoid survey was carried out on 45 taxa from the genera Shorea, Hopea, Parashorea, Neobalanocarpus, and Dryobalanops of the tribe Shoreae in the Dipterocarpaceae. The study showed significant chemotaxonomic differences in leaf flavonoid aglycone patterns and the presence of tannins in these taxa. The flavonoid patterns are useful in the delimitation of some taxa. For example, the genus Parashorea is distinguished by the universal presence of kaempferol 3‐methyl ether, and the monotypic genus Neobalanocarpus is unique in not producing ellagic and gallo tannins. The presence of chalcones and flavone C‐glycosides supports the separation of the genus Hopea into two sections, section Dryobalanoides and section Hopea in Ashton's classification, which is based on the type of venation. The flavonoid distributions in this study show that they can be very useful for differentiating between the Balau group in the genus Shorea and some scaly barked Hopea species, particularly H. helferi (lintah bukit), H. nutans (giam), and H. ferrea (malut). © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 755–762.  相似文献   

3.
A survey of flavonoids in the leaves of 81 species of the Zingiberales showed that, while most of the major classes of flavonoid are represented in the order, only two families, the Zingiberaceae and Marantaceae are rich in these constituents. In the Musaceae (in 9 species), Strelitziaceae (in 8 species) and Cannaceae (1 of 2 species) flavonol glycosides were detected in small amount and in the Lowiaceae no flavonoids were fully identified. In the Zingiberaceae kaempferol (in 22%), quercetin (72%) and proanthocyanidins (71%) are distributed throughout the family. The two subfamilies of the Zingiberaceae may be distinguished by the presence of myricetin (in 26%), isorhamnetin (10%) and syringetin (3%) in the Zingiberoideae and of flavone C-glycosides (in 86% of taxa) in the Costoideae. A number of genera have distinctive flavonol profiles: e.g. Hedychium species have myricetin and quercetin. Roscoea species isorhamnetin and quercetin and Alpinia species kaempferol and quercetin glycosides. A new glycoside, syringetin 3-rhamnoside was identified in Hedychium stenopetalum. In the Zingiberoideae flavonols were found in glycosidic combination with glucuronic acid, rhamnose and glucose but glucuronides were not detected in the Costoideae or elsewhere in the Zingiberales. The Marantaceae is chemically the most diverse group and may be distinguished from other members of the Zingiberales by the occurrence of both flavone O- and C-glycosides and the absence of kaempferol and isorhamnetin glycosides. The distribution of flavonoid constituents within the Marantaceae does not closely follow the existing tribai or generic limits. Flavonols (in 50% of species). flavones (20%) and flavone C-glycosides (40%) are found with similar frequency in the two tribes and in the genera Calathea and Maranta both flavone and flavonol glycosides occur. Apigenin- and luteolin-7-sulphates and luteolin-7,3′-disulphate were identified in Maranta bicolor and M. leuconeura var. kerchoveana and several flavone C-glycosides sulphates in Stromanthe sanguinea. Anthocyanins were identified in those species with pigmented leaves or stems and a common pattern based on cyanidin-and delphinidin-3-rutinosides was observed throughout the group. Finally the possible relationship of the Zingiberales to the Commelinales, Liliales, Bromeliales and Fluviales is discussed.  相似文献   

4.
In a leaf survey of 142 species from 75 genera of the Orchidaceae, flavone C-glycosides (in 53%) and flavonols (in 37 %) were found to be the most common constituents. However, since these compounds are not found uniformly and their distribution shows a strong correlation with plant geography, it is not possible to represent the Orchidaceae by a single flavonoid profile. Thus, flavone C-glycosides are most common in tropical and subtropical species of the Epidendroid and Vandoid tribes (in 63%) and flavonol glycosides are more characteristic of temperate species of the Neottioid tribes (in 78%). By contrast 6-hydroxyflavones (in 6 species), luteolin (in 2 species) and tricin as the 5-glucoside (in 1 species) are all rare. Three new glycosides were characterised: scutellarein 6-methyl ether 7-rutinoside from Oncidium excavatum and O. sphacelatum, pectolinarigenin 7-glucoside from 0. excavatutn and Eria javanica, and luteolin 3′,4′-diglucoside from Listera ovata. The xanthones, mangiferin and isomangiferin were found in Mormolyca ringens, Maxillaria aff. luteo-alba and 5 Polystachya species and a mangiferin sulphate tentatively identified in P. nyanzensis. Other unusual phenolic constituents include 6,7-methylenedioxy- and 6,7-dimethoxycoumarins from Dendrobium densiflorum and D. farmeri, formed by the rearrangement during the extraction process from the corresponding O-glucosyloxycinnamic acids. The origin and relationship of the Orchidaceae to other monocot groups are discussed in the light of the flavonoid evidence.  相似文献   

5.
6.
In a leaf survey of 61 species of the Bromeliaceae, an unexpectedly wide spectrum of flavonoid constituents was encountered. The family is unique amongst the monocotyledons in the frequency and variety of flavonoids with extra hydroxylation or methoxylation at the 6-position. More common flavonols (in 43% of species) and flavones (in 13%) are distributed throughout the family whereas the rarer flavonoid classes are restricted to one or two of the three subfamilies. Thus 6-hydroxyflavones were found in both the Pitcairnioideae (in 50%) and the Tillandsioideae (in 14%) but patuletin (in 19%), gossypetin (in 1 species) and methylated 6-hydroxymyricetin derivatives (in 24%) were detected only in the Tillandsioideae. A new flavonol, 6,3′,5′-trimethoxy-3,5,7-4′-tetrahydroxyflavone, was identified as the 3-glucoside in Tillandsia usneoides and a new glycoside, patuletin 3-rhamnoside, in Vriesea regina. Myricetin glycosides were found only in the Bromelioideae and their presence here and the concomitant absence of 6-hydroxyflavonoids could indicate the primitive condition of this subfamily. The flavonoid results, in toto, confirm the view based on morphology, that the Bromeliaceae occupies an isolated position in relation to other monocot families.  相似文献   

7.
In a leaf flavonoid survey of 59 specimens of the Winteraceae and related families, representing nine genera, luteolin 7,3′-dimethyl ether (in 77%) and flavonols (in 81%) were found to be major constituents. Indeed the high incidence of luteolin 7,3′-dimethyl ether chemically isolates the family from all other angiosperm groups, including families and genera that have been taxonomically associated with the Winteraceae in the past. Simple flavones (in 16%), on the other hand, were found only in some Drimys s. str., Tasmannia and Pseudowintera species. Similarly, the distribution of flavone C-glycosides was restricted to specimens of T. piperita and one specimen of D. winteri. The frequent occurrence of procyanidin (in 60%) and dihydroquercetin (in 44%) reflects the primitive and woody nature of the family. The combined flavonoid data clearly support previous cytological, morphological and phylogenetic studies in the division of the Winteraceae into three groups of genera: (1) Bubbia, Belliolum, Exospermum and Zygogynum; (2) Drimys s. str. and Pseudowintera and (3) Tasmannia. Some generic variations were found within the Bubbia, Belliolum, Expospermum and Zygogynum group but apart from minor geographic variations within Belliolum the flavonoid results do not appear to provide suitable evidence for subgeneric taxonomy.  相似文献   

8.
The anthocyanin and flavonol glycosides in Larkspur flowers (cv. Dark Blue Supreme) are delphinidin 3-di(p-hydroxybenzoyl)glucosylglucoside, kaempferol 3-robinobioside-7-rhamnoside (robinin), kaempferol 3-rutinoside, kaempferol 7-rhamnoside, and kaempferol 3-(caffeylgalactosylxyloside)-7-rhamnoside. As young flowers age the pH of epidermal tissue increases from 5·5 to 6·6 and the color of many of the cells changes from moderate reddish-purple to light purplish-blue. Many of the older cells also contain blue crystals. Visible absorption spectra of moderate reddish-purple and light purplish-blue cells were simulated with a solution of the anthocyanin (10−2 M) plus robinin (5 × 10−3 M) at pH 5·6 and 7·1, respectively. Changes in the absorption spectra of living tissue with heating or cooling and of concentrated solutions of the anthocyanin with dilution or moderate heat, indicate that in the natural state the pigment is present in an associated form.  相似文献   

9.
Hydroxycinnamoyl acid amides (HCA's) were found to be important components in the inflorescences of different Araceae species. HCA's occurred in large amount in spathes and in the male and female flowers, and were totally absent from the sterile flowers, commonly found on Araceae spadices. Differences in the distribution of HCA's were noted between male and female flowers. Thus the amount of neutral HCA's was always greater in the male than in the female flowers and the female flowers generally contained more basic HCA'S. In the inflorescences of some Araceae species in the Monsteroideae and Philodendroideae (genera Monstera, Raphidophora and Philodendron), the aromatic amines tyramine and dopamine were very abundant, with concentrations ranging from 1 to 4 mg of each amine per g fr. wt.  相似文献   

10.
This study aimed to determine the minimum inhibitory concentration (MIC) of kaempferol and quercetin against planktonic and biofilm forms of the Candida parapsilosis complex. Initially, nine C. parapsilosis sensu stricto, nine C. orthopsilosis and nine C. metapsilosis strains were used. Planktonic susceptibility to kaempferol and quercetin was assessed. Growing and mature biofilms were then exposed to the flavonoids at MIC or 10xMIC, respectively, and theywere also analyzed by confocal laser scanning microscopy. The MIC ranges were 32-128 µg ml?1 for kaempferol and 0.5-16 µg ml?1 for quercetin. Kaempferol and quercetin decreased (P?<?0.05) the metabolic activity and biomass of growing biofilms of the C. parapsilosis complex. As for mature biofilms, the metabolic effects of the flavonoids varied, according to the cryptic species, but kaempferol caused an overall reduction in biofilm biomass. Microscopic analyses showed restructuring of biofilms after flavonoid exposure. These results highlight the potential use of these compounds as sustainable resources for the control of fungal biofilms.  相似文献   

11.
By means of thin layer chromatography and gas liquid chromatography the distribution of monoterpenes and flavonoid aglycones in the leaves of 19 samples of 15 species of Acmadenia has been investigated. The distribution of flavonol and flavone aglycones shows a close agreement with recently proposed taxonomic divisions within the genus. It is proposed that these patterns may be of importance in interpreting the evolutionary development of the genus.  相似文献   

12.
A survey of 27 plants of Ilex and Euonymus revealed that the distribution of anthocyanins and cinnamic acid esters in their fruits is correlated with accepted taxonomic classification. In the skin of the fruit, the 3-xylosylglucoside of cyanidin and pelargonidin and the 3-monoglucoside of cyanidin were identified, and the hydrolysed fruit-extracts were found to contain quercetin, kaempferol and caffeic acid. The genus Ilex has been shown to be distinguishable from the genus Euonymus by their anthocyanins; I. micrococca was exceptional in having only chrysanthemin. Additionally, chlorogenic and isochlorogenic acids and caffeylglucose occur in Ilex but not in Euonymus. The microspectrophotometric examination of the pigment cells of the black- and red-Ilex fruits revealed that the position of absorption maxima in the visible region is mainly related to the relative amounts of anthocyanin and flavonol present.  相似文献   

13.
Six acylated delphinidin glycosides (pigments 1-6) and one acylated kaempferol glycoside (pigment 9) were isolated from the blue flowers of cape stock (Heliophila coronopifolia) in Brassicaceae along with two known acylated cyanidin glycosides (pigments 7 and 8). Pigments 1-8, based on 3-sambubioside-5-glucosides of delphinidin and cyanidin, were acylated with hydroxycinnamic acids at 3-glycosyl residues of anthocyanidins. Using spectroscopic and chemical methods, the structures of pigments 1, 2, 5, and 6 were determined to be: delphinidin 3-O-[2-O-(β-xylopyranosyl)-6-O-(acyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which acyl moieties were, respectively, cis-p-coumaric acid for pigment 1, trans-caffeic acid for pigment 2, trans-p-coumaric acid for pigment 5 (a main pigment) and trans-ferulic acid for pigment 6, respectively. Moreover, the structure of pigments 3 and 4 were elucidated, respectively, as a demalonyl pigment 5 and a demalonyl pigment 6. Two known anthocyanins (pigments 7 and 8) were identified to be cyanidin 3-(6-p-coumaroyl-sambubioside)-5-(6-malonyl-glucoside) for pigment 7 and cyanidin 3-(6-feruloyl-sambubioside)-5-(6-malonyl-glucoside) for pigment 8 as minor anthocyanin pigments. A flavonol pigment (pigment 9) was isolated from its flowers and determined to be kaempferol 3-O-[6-O-(trans-feruloyl)-β-glucopyranoside]-7-O-cellobioside-4′-O-glucopyranoside as the main flavonol pigment.On the visible absorption spectral curve of the fresh blue petals of this plant and its petal pressed juice in the pH 5.0 buffer solution, three characteristic absorption maxima were observed at 546, 583 and 635 nm. However, the absorption curve of pigment 5 (a main anthocyanin in its flower) exhibited only one maximum at 569 nm in the pH 5.0 buffer solution, and violet color. The color of pigment 5 was observed to be very unstable in the pH 5.0 solution and soon decayed. In the pH 5.0 solution, the violet color of pigment 5 was restored as pure blue color by addition of pigment 9 (a main flavonol in this flower) like its fresh flower, and its blue solution exhibited the same three maxima at 546, 583 and 635 nm. On the other hand, the violet color of pigment 5 in the pH 5.0 buffer solution was not restored as pure blue color by addition of deacyl pigment 9 or rutin (a typical flower copigment). It is particularly interesting that, a blue anthocyanin-flavonol complex was extracted from the blue flowers of this plant with H2O or 5% HOAc solution as a dark blue powder. This complex exhibited the same absorption maxima at 546, 583 and 635 nm in the pH 5.0 buffer solution. Analysis of FAB mass measurement established that this blue anthocyanin-flavonol complex was composed of one molecule each of pigment 5 and pigment 9, exhibiting a molecular ion [M+1] + at 2102 m/z (C93H105O55 calc. 2101.542). However, this blue complex is extremely unstable in acid solution. It really dissociates into pigment 5 and pigment 9.  相似文献   

14.
Two novel lactones have been isolated from the stem barks of Garcinia conrauana and G. mannii. The major component of the bark of G. conrauana was identified as 3-(3,? 3″-dimethylallyl)-conrauanalactone [4-hydroxy-3-(3″, 3″-dimethylallyl)-6-pentadecylpyran- 2-one] by comparison of spectral data of the isolated compound and two methylethers with that obtained for the previously isolated conrauanalactone. A minor component of the bark of G. mannii was tentatively identified as 3-α-hydroxy-5-(heptadec-8′-enyl)-tetrahydro- furan-2-one on the basis of spectral data from the isolated compound and its monoacetate. The distributions of biflavonoids and related compounds and benzophenones in the stem bark, heartwood, seeds and leaves of the two species are reported.  相似文献   

15.
The internal flavonoid patterns of Pityrogramma triangularis fronds were found to distinguish diploids and tetraploids of two exudate chemotypes (the ceroptin and the kaempferol methyl ether types). The flavonoid data suggest that the tetraploid-kaempferol methyl ether chemotype is of alloploid origin involving the two diploid chemotypes because the flavonoid pattern for the former represents a pattern additive of the two diploids, while the tetraploid-ceroptin chemotype may be of autoploid origin, as deduced from the similarity of the diploids and tetraploids.  相似文献   

16.
Diverse schemes have been proposed for the classification of the Commelinaceae on the basis of different characters. The leaf flavonoids of 152 species have been analysed. The flavone C-glycosides are the dominant compounds, found in 78% of the species examined. Flavonol O-glycosides are present in 28% of the species, quercetin being the most frequent aglycone. 6-Hydroxyluteolin was found mainly in Tradescantia but also in other species (10%). Tricin has been detected sporadically in less than 5% of the species. In spite of these variations the pattern of the family is very uniform, because the presence of C-glycoflavones and the distribution of the other compounds supports the scheme proposed by Rohweder who divided the family into Commelinieae and Tradescantieae on the basis of inflorescence characters.  相似文献   

17.
Hordeumin stored at –40 to –80oC in 1% HCI–methanol suffered neither from color reduction nor discoloration. After heating at 80°C for 60 min, hordeumin showed a pigment retention rate of 100%. This characteristic is because the pigment is a composite high-molecular weight compound consisting of anthocyanins and polyphenols, It was determined, however, that discoloration and browning occurred more rapidly than color reduction during storage and heating of the pigment.  相似文献   

18.
月腺大戟根中有效成分乙素和丙素的结构研究   总被引:2,自引:0,他引:2  
本文主要报道从月腺大戟(Euphorbia ebracteolata Hayata)根中分离出的对结核菌有抑制作用的晶Ⅵ(乙素)和晶Ⅶ(丙素)的化学结构。经化学反应及光谱鉴定,确定晶Ⅵ为2,4-二羟基-6-甲氧基-3-甲基-苯乙酮,晶Ⅶ为2-羟基-6-甲氧基-3-甲基-1-苯乙酮-4-6-葡萄糖甙。乙素为首次分离的天然产物,丙素为新的化合物。该植物提取物对结核病有明显疗效。  相似文献   

19.
Four European Pulicaria species, P. odora, P. paludosa, P. sicula and P. vulgare, were analysed for their surface and vacuolar constituents for comparison with previous data obtained for P. dysenterica. Each species had a distinct flavonoid pattern with notable differences between leaf and inflorescence. 6-Hydroxyflavonols were the major lipophilic components in all of the species and tissues except in the leaves of P. paludosa and P. vulgare, where scutellarein 6-methyl ether was the main constituent. In the leaves of P. sicula a more unusual flavone, 6-hydroxyluteolin 5,6,7,3',4'-pentamethyl ether, was a major component. Pulicaria odora was distinguished by the presence of a series of methylated 6-hydroxykaempferol derivatives including a 3,5,6,7,4'-pentamethyl ether. Quercetagetin hexamethyl ether occurred in both tissues of P. sicula together with the 3,7,3,4'-tetra methyl ether and other quercetagetin derivatives, which were 5-methylated. Quercetagetin 3,7,3'-methyl ether was present in all species except P. odora. Flavonol glucuronides were characteristic vacuolar constituents of all the taxa studied. Two rare glycosides, patuletin and 6-hydroxykaempferol 6-methyl ether 7-glucuronides were identified in the inflorescence of P. odora. Pulicaria vulgaris, a rare plant of southern England, had the vacuolar flavonoid profile most similar to the other more abundant British plant, P. dysenterica.  相似文献   

20.
The structures of five alkaloids present in Crinum augustum were elucidated by spectral arguments. Four of them were shown to be new and constitute two pairs of epimers: 6-α- and 6-β-hydroxybuphanisine and 6-α- and 6-β-hydroxycrinine. The fifth alkaloid was identified as crinamine.  相似文献   

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