PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Gentianaceae”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Morphological and ultrastructural diversity of orbicules in Gentianaceae.

Minute granules of sporopollenin, called orbicules, can be observed on the innermost tangential and/or radial walls of secretory tapetum cells. Orbicules were investigated in 53 species of 34 Gentianaceae genera using light microscopy, scanning electron microscopy and transmission electron microscopy. This selection covered all different tribes and subtribes recognized in Gentianaceae (87 genera, +/-1650 species). Orbicules were found in 38 species (23 genera) distributed among the six tribes recognized in Gentianaceae. The orbicule typology is based on those described previously in Rubiaceae. Of the six orbicule types described previously, Type II orbicules are lacking. Type III orbicules are most common (17 species). Hockinia Gardner is the only representative with Type I orbicules. The number of representatives with orbicules belonging to the other orbicule types are equally distributed among the species studied: seven species possess Type IV orbicules, six species Type V and six species Type VI. The systematic usefulness of this typology is discussed in comparison with the latest systematic insights within the family, and palynological trends in Gentianaceae. Orbicule data have proven to be useful for evaluating tribal delimitation within Rubiaceae and Loganiaceae s.l.; however, they seem not to be useful for tribal delimitation in Gentianaceae. In the tribes Potalieae and Gentianeae orbicule data may be useful at subtribal level.

Cytoplasmic Granules↗

Monophyly and relationships of the tribe Exaceae (Gentianaceae) inferred from nuclear ribosomal and chloroplast DNA sequences.

Both chloroplast trnL (UAA) intron and nuclear ribosomal ITS sequences highly confirmed the monophyly of the tribes of the Gentianaceae defined by the recent classification, and revealed the tribe Exaceae as a basal clade just next to the basal-most lineage, the tribe Saccifolieae. Within the tribe Exaceae, Sebaea (except Sebaea madagascariensis) appeared as the most basal clade as the sister group to the rest of the tribe. The Madagascan endemic genera Gentianothamnus and Tachiadenus were very closely related to each other, together standing as sister to a clade comprising Sebaea madagascariensis, Ornichia, and Exacum. The saprophytic genus Cotylanthera nested deeply inside Exacum. Sebaea madagascariensis was shown closer to the Madagascan endemic genus Ornichia than to any other sampled Sebaea species. Exacum appeared as the most derived taxon within this tribe. The topology of the phylogenetic trees conform with the Gondwana vicariance hypothesis regarding the biogeography of Exaceae. However, no evidence for matching the older relationships within the family to the tectonic history could be corroborated with various divergence time analyses. Divergence dating estimated a post-Gondwana diverging of the Gentianaceae about 50 million years ago (MYA), and the tribe Exaceae as about 40 MYA. The Mozambique Channel land-bridge could have played an important role in the biogeographic history of the tribe Exaceae.

Africa↗

The structural elucidation of a novel iridoid derivative from Tachiadenus longiflorus (Gentianaceae) using the LSD programme and quantum chemical computations.

Oleanolic acid, scoparone, scopoletin and a novel iridoid derivative, angelone, were isolated from Tachiadenus longiflorus (Gentianaceae). The structure of angelone was determined from NMR data, given as input to the Logic for Structure Determination Programme, and was finally confirmed by comparison of experimental 13C-NMR chemical shifts with those obtained by quantum mechanical calculations.

Gentianaceae↗

Inhibitory effects of the Gentiana macrophylla (Gentianaceae) extract on rheumatoid arthritis of rats.

Acute treatment of rheumatoid rats with an extract from the roots of Gentiana macrophylla (Gentianaceae) produced a significant inhibitory effect on rheumatoid arthritis (RA). When rats were administered the Gentiana macrophylla extract orally at a daily dose of 100 mg/kg body weight, the prostaglandin E(2) (PGE(2)) levels in the inflammatory tissues, sole thickness, and ankle circumferences of feet were significantly decreased. The anti-inflammatory activity observed in Gentiana macrophylla is comparable to that observed in prednisone. These observations suggest that Gentiana macrophylla displays considerable potency in anti-inflammatory action and could be used as an anti-inflammatory agent in the control of inflammation of rheumatoid arthritis.

Administration, Oral↗

Investigations of the Malagasy species Tachiadenus longiflorus Grisebach (Gentianaceae): linking chemical finding and traditional usage.

A decoction of the aerial parts of Tachiadenus longiflorus, a Gentianaceae endemic to Madagascar, is drunk to relieve stomach pains and dyspepsia; while a leaf decoction is drunk as a purgative or to relieve gall bladder ailments in folk medicine in Madagascar. The stem and bark have yielded a large amount of the triterpenoid, oleanolic acid, and the coumarins, scoparone and scopoletin. These compounds have been isolated previously from other sources and have shown broad pharmacological properties. We report the possible link between the compounds isolated and the traditional use of Tachiadenus longiflorus.

Gentianaceae↗

Reduced fecundity in small populations of the rare plant Gentianopsis ciliate (Gentianaceae).

Habitat destruction is the main cause for the biodiversity crisis. Surviving populations are often fragmented, i.e., small and isolated from each other. Reproduction of plants in small populations is often reduced, and this has been attributed to inbreeding depression, reduced attractiveness for pollinators, and reduced habitat quality in small populations. Here we present data on the effects of fragmentation on the rare, self-compatible perennial herb Gentianopsis ciliata (Gentianaceae), a species with very small and presumably well-dispersed seeds. We studied the relationship between population size, plant size, and the number of flowers produced in 63 populations from 1996-1998. In one of the years, leaf and flower size and the number of seeds produced per fruit was studied in a subset of 25 populations. Plant size, flower size, and the number of seeds per fruit and per plant increased with population size, whereas leaf length and the number of flowers per plant did not. The effects of population size on reproduction and on flower size remained significant if the effects were adjusted for differences in plant size, indicating that they could not be explained by differences in habitat quality. The strongly reduced reproduction in small populations may be due to pollination limitation, while the reduced flower size could indicate genetic effects.

Biodiversity↗

Phylogeny and biogeography of exacum (gentianaceae): a disjunctive distribution in the Indian ocean basin resulted from long distance dispersal and extensive radiation.

Disjunctive distributions across paleotropical regions in the Indian Ocean Basin (IOB) often invoke dispersal/vicariance debates. Exacum (Gentianaceae, tribe Exaceae) species are spread around the IOB, in Africa, Madagascar, Socotra, the Arabian peninsula, Sri Lanka, India, the Himalayas, mainland Southeast Asia including southern China and Malaysia, and northern Australia. The distribution of this genus was suggested to be a typical example of vicariance resulting from the breakup of the Gondwanan supercontinent. The molecular phylogeny of Exacum is in principle congruent with morphological conclusions and shows a pattern that resembles a vicariance scenario with rapid divergence among lineages, but our molecular dating analysis demonstrates that the radiation is too recent to be associated with the Gondwanan continental breakup. We used our dating analysis to test the results of DIVA and found that the program predicted impossible vicariance events. Ancestral area reconstruction suggests that Exacum originated in Madagascar, and divergence dating suggests its origin was not before the Eocene. The Madagascan progenitor, the most recent common ancestor of Exacum, colonized Sri Lanka and southern India via long-distance dispersals. This colonizer underwent an extensive range expansion and spread to Socotra-Arabia, northern India, and mainland Southeast Asia in the northern IOB when it was warm and humid in these regions. This widespread common ancestor retreated subsequently from most parts of these regions and survived in isolation in Socotra-Arabia, southern India-Sri Lanka, and perhaps mainland Southeast Asia, possibly as a consequence of drastic climatic changes, particularly the spreading drought during the Neogene. Secondary diversification from these surviving centers and Madagascar resulted in the extant main lineages of the genus. The vicariance-like pattern shown by the phylogeny appears to have resulted from long-distance dispersals followed by extensive range expansion and subsequent fragmentation. The extant African species E. oldenlandioides is confirmed to be recently dispersed from Madagascar.

Africa↗

The diversification of Halenia (Gentianaceae): ecological opportunity versus key innovation.

The plant genus Halenia (Gentianaceae) consists of herbs growing in temperate and tropical alpine habitats and most species possess flowers in which nectar is produced in spurs. This probably helps reward only specialized long-tongued pollinators, and a narrow pollinator/flower relationship is thought to accelerate diversification rates (a key innovation). To test the pattern of diversification of Halenia against the unspurred sister group we reconstructed phylogenetic relationships among 22 species plus outgroups using nuclear ITS and chloroplast rpl16 intron sequence data. We show that Halenia originated in East Asia and migrated via North America into Central America. From there, it colonized South America three times independently, probably within the last million years. Significant changes in diversification rates were found during the evolution of Halenia using a sister group method, a likelihood method, and a diversity-through-time plot. In contrast to other studies, we could not observe a direct speciation rate effect of the evolution of nectar spurs in comparison with the unspurred sister group of Halenia. Rather, increases in diversification occurred following the colonization of Central and South America by spurred progenitor taxa. This later switch in diversification may have resulted from the availability of new geographical and ecological opportunities, or from the availability of more and different pollinators in these regions. Following the latter hypothesis, the nectar spurs were a preadaption and functioned as a key innovation only in this new biotic environment. After an initial rapid increase, a reduction in diversification rate was observed in Central America, probably illustrating density dependence of speciation rates. Finally, we found preliminary evidence for the key innovation hypothesis in geologically young spurred and unspurred lineages of Halenia in South America.

Adaptation, Biological↗

Chemical constituents of Gentianaceae XXIV: Anti-Mycobacterium tuberculosis activity of naturally occurring xanthones and synthetic analogs.

Anti-Mycobacterium tuberculosis H37 RV data are presented for the individual xanthones of Canscora decussata Schult and Swertia purpurascens Wall (Gentianaceae); a few, from the former species, showed significant activity. Additionally, sturcture--activity relationships of these compounds are evaluated on the basis of the minimum inhibitory concentration data of 18 naturally occurring xanthones bearing 1,3,5- 1,3,5,6-, 1,3,6,7-, 1,3,5,8-, 1,3,5,6,7-, and 1,3.6,7,8-oxygenated patterns and six synthetic analogs.

Antitubercular Agents↗

Chemical constituents of gentianaceae XXVIII: flavonoids of Enicostemma hyssopifolium (Willd.) Verd.

The whole plant of Enicostemma hyssopifolium (Willd.) Verd. (Gentianaceae) was collected at different growth stages and was shown to contain seven flavonoids: apigenin (I), genkwanin (II), isovitexin (III), swertisin (IV), saponarin (V), 5-O-glucosylswertisin (VI), and 5-O-glucosylisoswertisin (VII). Compounds VI and VII previously were unreported in nature. The yields of the flavonoids varied with the growth stage. The biochemical and chemotaxonomic significance of these results is appraised.

Chemical Phenomena↗

Mutagenic activities of gentisin and isogentisin from Gentianae radix (Gentianaceae).

The mutagenic activities of 2 hydroxyxanthones, gentisin and isogentisin, obtained from the methanol extract of Gentianae radix (Gentianaceae) were investigated. The methanol extract of Gentianae radix, which showed mutagenicity in the Ames test in Salmonella typhimurium strain TA100 with S9 mix, was fractionated by column chromatography on Sephadex LH-20, and the fractions were purified by preparative TLC and column chromatography on polyamide. 2 mutagenic materials thus obtained, S1 and S2, each gave a single band on TLC. Identification of S1 and S2 was accomplished by comparing the analytical (mps, elementary analyses) and spectral (UV, IR, mass, NMR) results for S1 and S2 with literature data for gentisin and isogentisin. At doses below 10 micrograms, S1 (gentisin) and S2 (isogentisin) had similar specific mutagenic activities. At doses of over 10 to 50 micrograms, the mutagenic activities of S2 and S1 were 19.1 and 6.94 revertants per microgram respectively. This much lower activity of S1 than S2 may be a result of its poor solubility owing to the presence of the OMe group at C-3. The combined yield of S1 and S2 was about 76 mg (40 mg as S1 and 36 mg as S2), which accounted for 76% of the content of mutagenic compounds (100 mg) estimated roughly from the total mutagenic activity in the extract of the starting materials (100 g).

Animals↗

Generic delimitation and phylogenetic relationships within the subtribe Chironiinae (Chironieae: Gentianaceae), with special reference to Centaurium: evidence from nrDNA and cpDNA sequences.

To better understand the evolutionary history of the genus Centaurium and its relationship to other genera of the subtribe Chironiinae (Gentianaceae: Chironieae), molecular analyses were performed using 80 nuclear ribosomal ITS and 76 chloroplast trnLF (both the trnL UAA intron and the trnL-F spacer) sequences. In addition, morphological, palynological, and phytochemical characters were included to a combined data matrix to detect possible non-molecular synapomorphies. Phylogenetic reconstructions support the monophyly of the Chironiinae and an age estimate of ca. 22 million years for the subtribe. Conversely, both molecular data sets reveal a polyphyletic Centaurium, with four well-supported main clades hereafter treated as separate genera. The primarily Mediterranean Centaurium s.s. is closely related to southern African endemics Chironia and Orphium, and to the Chilean species Centaurium cachanlahuen. The resurrected Mexican and Central American genus Gyrandra is closely related to Sabatia (from eastern North America). Lastly, the monospecific genus Exaculum (Mediterranean) forms a monophyletic group together with the two new genera: Schenkia (Mediterranean and Australian species) and Zeltnera (all other indigenous American centauries). Several biogeographical patterns can be inferred for this group, supporting a Mediterranean origin followed by dispersals to (1) North America, Central America, and South America, (2) southern Africa (including the Cape region), and (3) Australia and Pacific Islands.

Base Sequence↗

Chemical constituents of gentianaceae XIV: tetraoxygenated and pentaoxygenated xanthones of Swertia purpurascens Wall.

The whole plant of Swertia purpurascens Wall. (Gentianaceae) has been shown to contain five tetraoxygenated and three pentaoxygenated zanthones. These are identified as 1,5,8-trihydroxy-3-methoxyxanthone, 1,3,8-trihydroxy-5-methoxyzanthone, 1-hydroxy-3,7,8-trimethoxyxanthone, 1,3,7,8-tetrahydroxyxanthone, 1,3,5,8-tetrahydroxyxanthone, and 1-hydroxy-3,4,7,8-tetramethoxyxanthone by chemical and spectral evidence. Additionally, the crude mixture of natural xanthones has been shown to include two partially emthylated pentaoxygenated xanthones as minor entities, which yield 1-hydroxy-3,4,7,8-tetramethoxyxanthone and 1-hydroxy-3,4,5,8-tetramethoxyxanthone on methylation. This is the first time that pentaoxygenated xanthones have been found in a member of the genus Swertia. 1-Hydroxy-3,4,7,8-tetramethoxyxanthone was previously known only as a synthetic compound. The total xanthones of S. purpurascens produce significant CNS stimulant actions, consistent with some therapeutic uses of the plant extract in the Indian system of medicine. The chemotaxonomic significance of the cooccurrence of various biogenetically related chemical characters in a single plant species is appraised.

Amphetamine↗

Anti-inflammatory activity and QSAR studies of compounds isolated from Hyacinthaceae species and Tachiadenus longiflorus Griseb. (Gentianaceae).

Twenty-two homoisoflavanones and structurally related compounds isolated from plants were screened for anti-inflammatory activity. Seventeen compounds were isolated from southern African Hyacinthaceae species, one from the Madagascan gentian Tachiadenus longiflorus Griseb. and four were of synthetic origin. Inhibition of prostaglandin synthesis in cell microsomal fractions was first evaluated, followed by screening for specific inhibition of isolated cyclooxygenase enzymes (COX-1 and COX-2). Six homoisoflavanone and structurally related compounds showed significantly high levels of anti-inflammatory activity in the microsomal fraction assay. Only one compound exhibited a high level of anti-inflammatory activity in the COX-1 enzyme assay and no significant activity was detected in the COX-2 enzyme assay. Biological screening was followed by a computer-based quantitative structure-activity relationship (QSAR) study. The physicochemical descriptors: strain energy, heat of formation, volume, surface area, aqueous phase energy, dipole moment, enthalpy, entropy, molar refractivity, parachor, density, refractive index, surface tension, polarizability, logP, Van der Waals interaction energy, Coulombic interaction energy and nonbonded interaction energy were used to characterize the structures of the homoisoflavanones and structurally related compounds. This study produced three equations with significant prediction values for the anti-inflammatory activity of the compounds investigated. The derived models also provided valuable parameter guidelines for those properties influencing the anti-inflammatory activity of the studied compounds.

Animals↗

Vasodilator activity of crude methanolic extract of Gentiana kokiana Perr. et Song. (Gentianaceae).

Gentiana kokiana Perr. et Song. is a plant employed in the traditional medicine of Tuscany (Italy) as antihypertensive remedy. The aim of this work was to evaluate a possible vascular action of the plant and to investigate its mechanism of action. The methanolic extract of roots showed an endothelium-independent vasodilator activity in aortic rings pre-contracted by norepinephrine (NE) 3 microM and a marked depression of the contracturant responses induced by KCl and caffeine, and by NE, both in Tyrode solution and Ca2+-free Tyrode solution. An action on the Ca2+-extracellular influx was discarded, while release or uptake mechanisms of the sarcoplasmic reticulum were hypothesized. However, the incapacity of cyclopiazonic acid (20 microM), a blocker of Ca2+/ATPase of the sarcoplasmic reticulum, to reduce the vasodilator action of the extract allowed to exclude the involvement of such a mechanism. A possible involvement of the ryanodine-sensitive Ca2+ channels is suggested.

Animals↗

Canscora decussata (Roxb.) Schult (Gentianaceae) inhibits LPS-induced expression of ICAM-1 and E-selectin on endothelial cells and carageenan-induced paw-edema in rats.

Inflammation is characterized pathologically by an increased supply of blood to the affected area, vasodilation, and infiltration of phagocytic, monocytic, and polymorphonuclear cells into the site of inflammation. The infiltration of leukocytes is in part regulated by the increased expression of cell adhesion molecules viz. ICAM-1 and E-selectin on endothelial cells. We investigated the effect of ethanolic extract prepared from plant Canscora decussata on expression of ICAM-1 and E-selectin on endothelial cells. Our results demonstrated that treatment of human endothelial cells with the extract down-regulated the LPS-induced expression of ICAM-1 and E-selectin. To study further the anti-inflammatory activity of the extract, we evaluated its effect in a rat model of carageenan-induced paw-edema. Our results showed that the extract was able to reduce the edema formation in a dose-dependent manner. These results, therefore, indicate that Canscora decussata extract could be useful towards developing effective anti-inflammatory agent(s) in the future.

Animals↗

Molecular systematics and biogeography of Crawfurdia, Metagentiana and Tripterospermum (Gentianaceae) based on nuclear ribosomal and plastid DNA sequences.

BACKGROUND AND AIMS: The systematic position of the genus Metagentiana and its phylogenetic relationships with Crawfurdia, Gentiana and Tripterospermum have not been explicitly addressed. These four genera belong to one of two subtribes (Gentianinae) of Gentianeae. The aim of this paper is to examine the systematic position of Crawfurdia, Metagentiana and Tripterospermum and to clarify their phylogenetic affinities more clearly using ITS and trnL intron sequences. METHODS: Nucleotide sequences from the internal transcribed spacers (ITS) of nuclear ribosomal DNA and the plastid DNA trnL (UAA) intron were analysed phylogenetically. Ten of fourteen Metagentiana species were sampled, together with 40 species of other genera in the subtribe Gentianinae. KEY RESULTS: The data support several previously published conclusions relating to the separation of Metagentiana from Gentiana and its closer relationships to Crawfurdia and Tripterospermum based on studies of gross morphology, floral anatomy, chromosomes, palynology, embryology and previous molecular data. The molecular clock hypothesis for the tested sequences in subtribe Gentianinae was not supported by the data (P < 0.05), so the clock-independent non-parametric rate smoothing method was used to estimate divergence time. This indicates that the separation of Crawfurdia, Metagentiana and Tripterospermum from Gentiana occurred about 11.4-21.4 Mya (million years ago), and the current species of these three genera diverged at times ranging from 0.4 to 6.2 Mya. CONCLUSIONS: The molecular analyses revealed that Crawfurdia, Metagentiana and Tripterospermum do not merit status as three separate genera, because sampled species of Crawfurdia and Tripterospermum are embedded within Metagentiana. The speciation and rapid radiation of these three genera is likely to have occurred in western China as a result of upthrust of the Himalayas during the late Miocene and the Pleistocene.

DNA, Plant↗