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1.
PhytoKeys ; 243: 113-119, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947551

RESUMO

Impatienskarenensis (I.sect.Semeiocardium) from Kayin State, Myanmar is described and illustrated here. It is most similar to I.micromeris, but differs in having lower petals with outer margins strongly undulate in the lower half (vs. lower petals entire), apex of upper petals acute to obtuse (vs. apex rounded), short stout spur, ± as long as the depth of lower sepal, ca. 2.5 mm long (vs. long attenuate spur, twice as long as the depth of lower sepal, ca. 5 mm long). Its conservation status is also assessed as Critically Endangered.

2.
PLoS One ; 19(6): e0302283, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38900825

RESUMO

Pollination biology in the widespread species Impatiens capensis Meerb. has only been studied in America, specifically in zones of the U.S.A. and Canada. In this study, we investigated the pollination biology of I. capensis using an integrative identification approach using morphological and molecular tools in four populations of Northwest Poland. We also determined and compared the functional characteristics of the pollinators of the introduced species from the study sites and the native ones reported, for the latter collecting information from bibliographic sources. Visitors were identified using standard morphological keys, including identifying and classifying insect mouthparts. Molecular identification was carried out using mitochondrial DNA's cytochrome oxidase subunit I (COI). We morphologically identified 20 species of visitors constituted by 17 pollinators and three nectar robbers. DNA barcoding of 59 individuals proved the identification of 18 species (also 18 BINs). The frequency of pollinator species was primarily made up of representatives of both Hymenoptera (75%) and Diptera (21%). The morphological traits, such as the chewing and sucking mouthparts, small and big body height, and robber and pollinator behavior explained mainly the native and introduced visitors' arrangements that allow pollination success. However, to understand the process comprehensively, further investigation of other causalities in pollination success and understanding the diversity of pollinators in outer native ranges are necessary.


Assuntos
Impatiens , Espécies Introduzidas , Polinização , Polinização/fisiologia , Animais , Impatiens/fisiologia , Impatiens/genética , Dípteros/fisiologia , Dípteros/anatomia & histologia , Polônia , Código de Barras de DNA Taxonômico , Himenópteros/fisiologia
3.
Sci Rep ; 14(1): 13967, 2024 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886585

RESUMO

Twelve polyoxygenated cyclohex(a/e)ne diterpene esters, named albiflorenes A-L (1-12), were isolated from the whole plants of Kaempferia albiflora, known as "Prao Mang Mum." Their structures and relative stereochemistry were determined by extensive spectroscopic analysis. Furthermore, the comparison of experimental electronic circular dichroism (ECD) curves with the curves predicted by TDDFT was used to determine the absolute configurations. Albiflorenes contain polyoxygenated cyclohexane (or cyclohexene) derivatives, which are linked to either isopimarane or abietane diterpene acid units. The discovery marks the first occurrence of a conjugate between polyoxygenated cyclohexane (or cyclohexene) rings and diterpenoids. Among the isolates, albiflorene C specifically exhibited antibacterial activity against Bacillus cereus with MIC and MBC values of 3.13 and 6.25 µg/mL, respectively.


Assuntos
Antibacterianos , Diterpenos , Ésteres , Testes de Sensibilidade Microbiana , Zingiberaceae , Diterpenos/química , Diterpenos/farmacologia , Diterpenos/isolamento & purificação , Ésteres/química , Ésteres/farmacologia , Zingiberaceae/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bacillus cereus/efeitos dos fármacos , Estrutura Molecular , Dicroísmo Circular
4.
PhytoKeys ; 238: 147-155, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38420601

RESUMO

Bulbophyllumromklaoense (B.sect.Lemniscata) from northern Thailand is described and illustrated as a species new to science. It is most similar to B.muscarirubrum and B.triste, but differs by having inflorescences with only 4-6 reddish-brown flowers, falcate-subovate lateral sepals that are connate only in the upper half along the interior margins, petals with erose to fimbriate margins and a lip with long cilia in the distal half on the lower surface. A comparison with other similar species in the section, as well as notes on ecology, phenology, conservation assessment and a key to B.sect.Lemniscata in Thailand are also provided.

5.
Nat Prod Bioprospect ; 13(1): 55, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38036688

RESUMO

Four highly oxidized pimarane diterpenoids were isolated from Kaempferia takensis rhizomes. Kaemtakols A-C possess a tetracyclic ring with either a fused tetrahydropyran or tetrahydrofuran motif. Kaemtakol D has an unusual rearranged A/B ring spiro-bridged pimarane framework with a C-10 spirocyclic junction and an adjacent 1-methyltricyclo[3.2.1.02,7]octene ring. Structural characterization was achieved using spectroscopic analysis, DP4 + and ECD calculations, as well as X-ray crystallography, and their putative biosynthetic pathways have been proposed. Kaemtakol B showed significant potency in inhibiting nitric oxide production with an IC50 value of 0.69 µM. Molecular docking provided some perspectives on the action of kaemtakol B on iNOS protein.

6.
Plants (Basel) ; 12(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37111826

RESUMO

Classification of the banana family (Musaceae) into three genera, Musa, Ensete and Musella, and infrageneric ranking are still ambiguous. Within the genus Musa, five formerly separated sections were recently merged into sections Musa and Callimusa based on seed morphology, molecular data and chromosome numbers. Nevertheless, other key morphological characters of the genera, sections, and species have not been clearly defined. This research aims to investigate male floral morphology, classify members of the banana family based on overall similarity of morphological traits using 59 banana accessions of 21 taxa and make inferences of the evolutionary relationships of 57 taxa based on ITS, trnL-F, rps16 and atpB-rbcL sequences from 67 Genbank and 10 newly collected banana accessions. Fifteen quantitative characters were examined using principal component analysis and canonical discriminant analysis and 22 qualitative characters were analyzed by the Unweighted Pair Group Method with an Arithmetic Mean (UPGMA). The results showed that fused tepal morphology, median inner tepal shape and length of style supported the three clades of Musa, Ensete and Musella, while shapes of median inner tepal and stigma classified the two Musa sections. In conclusion, a combination of morphological characters of male flowers and molecular phylogenetics well support the taxonomic arrangement within the banana family and the Musa genus and assist in selection of characters to construct an identification key of Musaceae.

7.
Plants (Basel) ; 12(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36771515

RESUMO

The genus Paris is an important and confusing taxon due to high variation within species, and differences between species are sometimes difficult to delimit. Thus, the status of some taxa has changed over time. To clarify the status of Paris species for plant conservation and effective management of this genus in Thailand, we performed an intensive survey in northern Thailand, studied morphological characteristics, and constructed a molecular phylogenic tree, which we compared to recently published results of this genus. Our results indicate that there are two species in Thailand: P. yunnanensis and a new species, P. siamensis. Detailed descriptions, illustrations, and the phylogenetic position of these two species are provided here.

8.
Ann Bot ; 127(2): 267-280, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33091107

RESUMO

BACKGROUND AND AIMS: Floral diversity as a result of plant-pollinator interactions can evolve by two distinct processes: shifts between pollination systems or divergent use of the same pollinator. Although both are pollinator driven, the mode, relative importance and interdependence of these different processes are rarely studied simultaneously. Here we apply a phylogenetic approach using the Balsaminaceae (including the species-rich genus Impatiens) to simultaneously quantify shifts in pollination syndromes (as inferred from the shape and colour of the perianth), as well as divergent use of the same pollinator (inferred from corolla symmetry). METHODS: For 282 species we coded pollination syndromes based on associations between floral traits and known pollination systems, and assessed corolla symmetry. The evolution of these traits was reconstructed using parsimony- and model-based approaches, using phylogenetic trees derived from phylogenetic analyses of nuclear ribosomal and plastid DNA sequence data. KEY RESULTS: A total of 71 % of studied species have a bee pollination syndrome, 22 % a bimodal syndrome (Lepidoptera and bees), 3 % a bird pollination syndrome and 5 % a syndrome of autogamy, while 19 % of species have an asymmetrical corolla. Although floral symmetry and pollination syndromes are both evolutionarily labile, the latter shifts more frequently. Shifts in floral symmetry occurred mainly in the direction towards asymmetry, but there was considerable uncertainty in the pattern of shift direction for pollination syndrome. Shifts towards asymmetrical flowers were associated with a bee pollination syndrome. CONCLUSION: Floral evolution in Impatiens has occurred through both pollination syndrome shifts and divergent use of the same pollinator. Although the former appears more frequent, the latter is likely to be underestimated. Shifts in floral symmetry and pollination syndromes depend on each other but also partly on the region in which these shifts take place, suggesting that the occurrence of pollinator-driven evolution may be determined by the availability of pollinator species at large geographical scales.


Assuntos
Balsaminaceae , Polinização , Animais , Abelhas , Flores , Filogenia , Síndrome
9.
PhytoKeys ; 124: 139-147, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303809

RESUMO

Impatiensjenjittikuliae Ruchis. & Suksathan, a new species from a limestone area in Thasongyang District, Tak Province, Northern Thailand, is described and illustrated. This endemic new species is distinguished from the most similar, I.lacei Hook.f. through having pilose lateral sepals vs glabrous, and by the absence of long hairs along the lamina margin. Its pollen and seed morphology, stem anatomy, and pollination ecology are also observed. Furthermore, its conservation status as Critically Endangered is also assessed.

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