Publications by authors named "Nguyen Thanh Tra"

Phytochemical study of the leaves of Guillaumin resulted in the isolation of a new natural product egonol-3''-sulphate (), and two new derivatives egonol-3-methylD-galactopyranoside () and 7-methoxy-2-(3',4'-methylenedioxyphenyl)-benzofuran-5-carboxamide (). Their chemical structures were -elucidated by spectroscopic data. Compounds and significantly established a great role for the chemotaxonomic aspect.

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The current report describes the chemical investigation and biological activity of extracts produced by three fungal strains Fusarium oxysporum, Penicillium simplicissimum, and Fusarium proliferatum isolated from the roots of Piper nigrum L. growing in Vietnam. These fungi were namely determined by morphological and DNA analyses.

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Three new xanthones, garcicowanones C-E (), and six known xanthones () were isolated from the roots of Roxb. ex Choisy. Their chemical structures were determined using spectroscopic technics, including HR-ESI-MS and 2 D NMR.

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Three prenylated xanthones, garcinone E (1: ), bannaxanthone D (2: ) and bannanxanthone E (3: ) were isolated from the leaves of Graib. Their structures were elucidated by spectral methods and compared with literature data. To evaluate their anti-proliferative effects in tumor cells, firstly, cisplatin was used as a positive control and the effects of compound 1:  - 3: were determined by performing MTT assay in MDA-MB-231, CNE-2 and A549 cancer cells.

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Herbaceous annual plants of the genus Xanthium are widely distributed throughout the world and have been employed medicinally for millennia. This contribution aims to provide a systematic overview of the diverse structural classes of Xanthium secondary metabolites, as well as their pharmacological potential. On searching in various reference databases with a combination of three keywords "Xanthium", "Phytochemistry", and "Pharmacology", relevant publications have been obtained subsequently.

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Three new xanthones, garcimckeans A-C () were isolated from the methanol extract of the stems of (Clusiaceae). Their structures were established by extensive spectroscopic analysis (HR-ESI-MS and 1 D and 2 D NMR) and by comparison of the spectral data with those reported in the literature. Compounds displayed weak cytotoxic activity toward KB, Lu, HepG2, and MCF7 cell lines using the MTT assay with IC values ranging from 71.

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From the ethyl acetate extract (EtOAc) of the Vietnamese leaves, a new flavone 8--glycoside 2'',6''-di--acetylvitexin (), together with six known analogs were isolated. Their structures were determined by spectral methods and compared with literature data. In α-glucosidase inhibitory assay, the EtOAc extract and its flavone and biflavone derivatives possessed the significant IC range of 9.

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Searching for bioactive agents from medicinal plants, eleven constituents were isolated from Polyscias guilfoylei stem for the first time, including a nucleoside uracil (1), two sterols β-sitosterol (2) and daucosterol (3), a saponin androseptoside A (4), two lignans (+)-pinoresinol (5) and (+)-syringaresinol (6), four phenolic acids protocatechuic acid (7), methyl protocatechuate (8), caffeic acid (9), and 5-O-caffeoylquinic acid (10), and a flavonoid quercitrin (11). Metabolites 1, 4, and 6-11 have never been observed in genus Polyscias before. Phenolic compounds 7 and 9 possessed the respective IC values of 21.

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New propene derivative 1-(3,4-methylenedioxyphenyl)-2-(2-hydroxy-5-(3-hydroxypropyl)-3-methoxyphenyl)prop-2-en-1-one (), along with three known triterpenoids ursolic acid (), pomolic acid (), and maslinic acid () were isolated from the leaves of species. All structures were assigned by spectroscopic analysis. Compound showed potent cytotoxicity against four cancer cell lines (KB, HepG2, Lu, and MCF7) with the IC values of 3.

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A series of novel podophyllotoxin-naphthoquinone compounds 5a-p were synthesized in good yields using microwave-assisted four-component reactions of 2-hydroxy-1,4-naphthoquinone, aromatic benzaldehydes, tetronic acid and ammonium acetate. All the synthesized compounds were fully characterized by spectral data and evaluated for their cytotoxicity activities against KB, HepG2, Lu1, MCF7, and non-cancerous Hek-293 cell lines. Among 16 new compounds screened, compounds 5a, 5d, 5h, and 5k displayed high potent inhibitory activities with IC < 40 nM against HepG2 and SK-Lu-1 cell lines, and showed lower toxicity for non-cancerous Hek-293 cell line, demonstrating the potential importance of these compounds in the development of potential anticancer agents.

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Background: Centipeda minima (the family Asteraceae) is an annual herbaceous plant native to the tropical regions, especially in eastern tropical Asia. C. minima is well-known in the list of medicinal plants with capacities in treatment of whooping cough, nasal allergy, malaria, and asthma.

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Article Synopsis
  • Azurin, a bacteriocin from Pseudomonas aeruginosa, demonstrates the ability to selectively kill cancer cells and has been developed into a drug for brain tumor glioma after passing two phase I trials.
  • The study focuses on enhancing screening methods and analyzing genetic diversity of Azurin and related genes within P. aeruginosa and human gut microbiomes, particularly in a specific Vietnamese population.
  • This research successfully optimizes techniques for detecting these genes and identifies three synthetic Azurin-like proteins with promising anticancer properties, marking a first step in developing anticancer treatments derived from the human microbiome.
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Knowledge of the vibrational structure of a semiconductor is essential for explaining its optical and electronic properties and enabling optimized materials selection for optoelectronic devices. However, measurement of the vibrational density of states of nanomaterials is challenging. Here, using the example of colloidal nanocrystals (quantum dots), we show that the vibrational density of states of nanomaterials can be accurately and efficiently measured with inelastic X-ray scattering (IXS).

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Four new dammarane-type triterpenoids (1-4) and twelve known compounds (5-16) were isolated from the leaves of Viburnum sambucinum Reinw. ex Blume. Their structures were determined by spectral data analysis, including MS and 2D NMR.

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This study is carried out in the context of III-V semiconductor monolithic integration on silicon for optoelectronic device applications. X-ray diffraction is combined with atomic force microscopy and scanning transmission electron microscopy for structural characterization of GaP nanolayers grown on Si. GaP has been chosen as the interfacial layer, owing to its low lattice mismatch with Si.

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