Ferns belong to species-rich group of land plants, encompassing more than 11,000 extant species, and are crucial for reflecting terrestrial ecosystem changes. However, our understanding of their biodiversity hotspots, particularly in Southeast Asia, remains limited due to scarce genetic data. Despite harboring around one-third of the world's fern species, less than 6% of Southeast Asian ferns have been DNA-sequenced.
View Article and Find Full Text PDFThis phytochemistry investigation on the trunk of L. resulted in the isolation of three triterpenoids, including a new gammacerane triterpenoid - morusacerane (); along with two known compounds of betulinic acid () and ursolic acid (). The structure elucidation was thoroughly conducted based on 1D, 2D-NMR and HRESIMS spectra, followed by a comparison with existing literatures.
View Article and Find Full Text PDFis described as a new species endemic to Vietnam. It is unique in the genus in having an oblong-elliptic spathe limb with an obtuse apex and yellowish-greenish filiform staminodes with a down-curved acumen. The ecology, distribution and assessment of the conservation status of the new taxon, as well as a key to all known species in Vietnam, are provided.
View Article and Find Full Text PDFSituated in the southern end of the Annamite Mountain Range, Langbiang Plateau is a major biodiversity hotspot of southern Vietnam known for high species diversity and endemicity. To achieve effective conservation, parts of the plateau were designated as the Langbiang Biosphere Reserve, an UNESCO World Network aiming to improve relationships between inhabitants and their environments. Amongst the rich endemic flora of the plateau are three gesneriads ascribed to Primulina, a calciphilous genus with high species diversity in the vast limestone karsts stretching from southern China to northern Vietnam.
View Article and Find Full Text PDFis described as a new species from Khanh Hoa Province, southern Central Vietnam. It is distinct in the genus in having scutellate leaves that make it a highly potential ornamental plant. The new species looks like in general shapes, sizes and colours of habit, inflorescence, flower, and leaf but is distinguishable by adaxially glabrous and abaxially strigose leaves with serrate margins, scutellate leaf blade and appressed downwards tomentose petiole, sparsely glandular hairs on apical 1/2 of the gynoecium and trapeziform one-lipped stigma with slightly emarginated apex.
View Article and Find Full Text PDFChemical investigation on chloroform extract of led to the isolation of one new compound namely turgidol, together with five known triterpenoids, lupeol, lupenone, betulin, betulinic acid, and taraxerol. Their structures and stereochemistry have been determined by 1 D and 2 D NMR analysis, high resolution mass spectrometry, and compared with those in literatures. The relative configuration of turgidol was defined using DFT-NMR chemical shift calculations and subsequent DP4+ probability method.
View Article and Find Full Text PDFHeterotrophic plants provide intriguing examples of reductive evolution. This is especially evident in the reduction of their plastid genomes, which can potentially proceed toward complete genome loss. Several milestones at the beginning of this path of degradation have been described; however, little is known about the latest stages of plastome reduction.
View Article and Find Full Text PDFTruxinic acid sucrose diesters analogs possess interesting chemical structure by the presence of cyclobutane-ring and macrocyclic sucrose diesters moieties which are rarely found from natural sources. This paper describes the isolation and structural elucidation of four new sucrose diesters of substituted truxinic acids, trigohonbanosides A-D (1-4), from the leaves of Trigonostemon honbaensis. Their chemical structures were elucidated by HR-ESI-MS, NMR, and CD spectroscopic methods.
View Article and Find Full Text PDFIn our search for cytotoxic constituents from Vietnamese plants, the methanolic extract of was found to exhibit significant cytotoxic effect. Subsequent phytochemical investigation of ethyl acetate fractions of this plant led to isolation of 11 compounds including one new arylbenzofuran rhamnoside namely aristolochiaside (), two aristololactams ( and ), three lignanamides (-) and five phenolic amides (-). Their structures were elucidated by 1 D and 2 D NMR and HR-QTOF-MS experiments.
View Article and Find Full Text PDFIn our search for anti-inflammatory constituents from Vietnamese plants, the methanolic extract of was found to exhibit inhibitory effect on LPS-induced NO production in RAW264.7 cells. Phytochemical investigation of this plant led to isolation of four sulphated flavones (), including one new compound 5,3',4'-trihydroxy-7-methoxy-8--sulphate flavone (), and two pregnane-type steroids ( and ), including one new compound 7--heligenin B ().
View Article and Find Full Text PDFThe Chinese water pine is the sole surviving species of the genus . It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of in China have remained unknown up to now.
View Article and Find Full Text PDFBackground: Sapria is a distinctive and narrowly host-specific holoparasitic genus belonging to the Rafflesiaceae. Sapria himalayana, rare throughout its range from NE India, SW China, Thailand to Vietnam, is a little-understood species first recorded for Vietnam in 1959, and only recollected there over half a century later in February 2017. This has facilitated an assessment of its taxonomic identity and our understanding of its morphology and natural history aspects.
View Article and Find Full Text PDFIn the original version of this Article, an incorrect sample size was provided for the number of relict species (443 instead of 442) and the number of relict forests (423 instead of 422). These errors have been corrected in both the PDF and HTML versions of the Article.
View Article and Find Full Text PDFThe ethyl acetate extract of the rhizomes of (Roxb.) Buch. - Ham.
View Article and Find Full Text PDFToday East Asia harbors many "relict" plant species whose ranges were much larger during the Paleogene-Neogene and earlier. The ecological and climatic conditions suitable for these relict species have not been identified. Here, we map the abundance and distribution patterns of relict species, showing high abundance in the humid subtropical/warm-temperate forest regions.
View Article and Find Full Text PDFCaryota mitis L., a flowering plant, belongs to the family Arecaceae. In Vietnam, its fruits were used to treat joint pain.
View Article and Find Full Text PDFContext: Paramignya trimera (Oliv.) Burkill (Rutaceae) has been used to treat liver diseases and cancer. However, the anti-inflammatory effects of this medicinal plant and its components have not been elucidated.
View Article and Find Full Text PDFTwo new triterpene saponins, camelliosides I and J (1 and 2), two new megastigmane glycosides, camellistigosides A and B (3 and 4), and two known megastigmane glycosides, icariside B (5) and (6S,9R)-roseoside (6), were isolated from a methanol extract of the Camellia bugiamapensis leaves using various chromatographic separation techniques. Their structures were elucidated based on spectroscopic analyses, including HR ESI MS, CD, 1D and 2D NMR. Their inhibitory effects on LPS-induced NO production in RAW264.
View Article and Find Full Text PDFBackground And Aims: The gametophyte phase of ferns plays an important role in habitat selection, dispersal, adaptation and evolution. However, ecological studies on fern gametophytes have been impeded due to the difficulty of species identification of free-living gametophytes. DNA barcoding provides an alternative approach to identifying fern gametophytes but is rarely applied to field studies.
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