Cau Giay, Vietnam
Cau Giay, Vietnam

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Phan H.T.,Leibniz Institute of Plant Genetics and Crop Plant Research | Phan H.T.,Institute of Biotechnology IBT | Pohl J.,Hochschule Anhalt | Floss D.M.,Heinrich Heine University Düsseldorf | And 7 more authors.
Plant Biotechnology Journal | Year: 2013

Summary: Reducing the cost of vaccine production is a key priority for veterinary research, and the possibility of heterologously expressing antigen in plants provides a particularly attractive means of achieving this. Here, we report the expression of the avian influenza virus haemagglutinin (AIV HA) in tobacco, both as a monomer and as a trimer in its native and its ELPylated form. We firstly presented evidence to produce stabilized trimers of soluble HA in plants. ELPylation of these trimers does not influence the trimerization. Strong expression enhancement in planta caused by ELPylation was demonstrated for trimerized H5-ELP. ELPylated trimers could be purified by a membrane-based inverse transition cycling procedure with the potential of successful scale-up. The trimeric form of AIV HA was found to enhance the HA-specific immune response compared with the monomeric form. Plant-derived AIV HA trimers elicited potentially neutralizing antibodies interacting with both homologous virus-like particles from plants and heterologous inactivated AIV. ELPylation did not influence the functionality and the antigenicity of the stabilized H5 trimers. These data allow further developments including scale-up of production, purification and virus challenge experiments with the final goal to achieve suitable technologies for efficient avian flu vaccine production. Copyright © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd 115 June 2013 10.1111/pbi.12049 Research Article Research articles © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.


Pham T.T.,Vietnam Academy of Science and Technology | Chu V.T.,Vietnam Academy of Science and Technology | Bui T.V.H.,Hanoi University of Science | Nguyen T.T.,National Institute of Hygiene and Epidemiology NIHE | And 7 more authors.
Aquatic Microbial Ecology | Year: 2015

Viruses inhabiting the surface mucus layer of scleractinian corals have received little ecological attention so far. Yet they have recently been shown to be highly abundant and could even play a pivotal role in coral health. A fundamental aspect that remains unresolved is whether their abundance and diversity change with the trophic state of their environment. The present study examined the variability in the abundance of viral and bacterial epibionts on 13 coral species collected from 2 different sites in the Ha Long Bay, Vietnam: one station heavily affected by anthropogenic activity (Cat Ba Island) and one protected offshore station (Long Chau Island). In general, viral abundance was significantly higher in coral mucus (mean = 10.6 ± 2.0 × 107 viruslike particles ml-1) than in the surrounding water (5.2 ± 1.3 × 107 virus-like particles ml-1). Concomitantly, the abundance and community diversity (inferred from phylogenetic and morphological analyses) of their mucosal bacterial hosts strongly differed from their planktonic counterparts. Surprisingly, despite large differences in water quality and nutrient concentrations between Cat Ba and Long Chau, there were no significant differences in the concentrations of epibiotic viruses and bacteria measured in the only 2 coral species (i.e. Pavona decussata and Lobophyllia flabelliformis) that were common at both sites. The ability of corals to shed bacteria to compensate for their fast growth in nutrient-rich mucus is questioned here. © 2015 Inter-Research.


Ngoan B.T.,Vietnam Academy of Science and Technology | Hanh T.T.H.,Vietnam Academy of Science and Technology | Vien L.T.,Vietnam Academy of Science and Technology | Diep C.N.,Vietnam Academy of Science and Technology | And 9 more authors.
Journal of Asian Natural Products Research | Year: 2015

Using combined chromatographic methods, two asterosaponins (compounds 1 and 2), including a new compound novaeguinoside E (compound 1), and six glycosylated polyhydroxysteroids (compounds 3–8) were isolated from a methanol extract of the starfish Culcita novaeguineae. Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H–1H COSY, ROESY, and HRESI-MS) and by comparison with the literature values. The new compound 1 represents the third example of asterosaponins containing the 5α-cholesta-9(1l)-en-3β,6α,20,22-tetraol aglycone. Among isolated compounds, 4–7 exhibited moderate to weak cytotoxic activities against five human cancer cell lines such as Hep-G2 (hepatoma), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma). © 2015 Taylor & Francis


Bettarel Y.,Montpellier University | Bouvier T.,Montpellier University | Agis M.,Montpellier University | Bouvier C.,Montpellier University | And 10 more authors.
Microbial Ecology | Year: 2011

Although the structure and dynamics of planktonic viruses in freshwater and seawater environments are relatively well documented, little is known about the occurrence and activity of these viruses in estuaries, especially in the tropics. Viral abundance, life strategies, and morphotype distribution were examined in the Bach Dang Estuary (Vietnam) during the dry season in 2009. The abundance of both viruses and their prokaryotic hosts decreased significantly from upstream to downstream, probably as the result of nutrient dilution and osmotic stress faced by the freshwater communities. The antibiotic mitomycin-C revealed that the fraction of lysogenic cells was substantially higher in the lower seawater part of the estuary (max 27.1%) than in the upper freshwater area where no inducible lysogens were observed. The question of whether there is a massive, continuous induction of marine lysogens caused by the mixing with freshwater is considered. Conversely, the production of lytic viruses declined as salinity increased, indicating a spatial succession of viral life strategies in this tropical estuary. Icosahedral tailless viruses with capsids smaller than 60 nm dominated the viral assemblage throughout the estuary (63.0% to 72.1% of the total viral counts), and their distribution was positively correlated with that of viral lytic production. Interestingly, the gamma-proteobacteria explained a significant portion of the variance in the < 60 nm and 60 to 90 nm tailless viruses (92% and 80%, respectively), and in the Myoviridae (73%). Also, 60% of the variance of the tailless larger viruses (> 90 nm) was explained by the beta-proteobacteria. Overall, these results support the view that the environment, through selection mechanisms, probably shapes the structure of the prokaryotic community. This might be in turn a source of selection for the virioplankton community via specific affiliation favoring particular morphotypes and life strategies. © 2011 Springer Science+Business Media, LLC.


Thanh N.V.,Vietnam Academy of Science and Technology | Ngoc N.T.,Vietnam Academy of Science and Technology | Anh H.L.T.,Vietnam Academy of Science and Technology | Thung D.C.,Institute of Marine Environment and Resources IMER | And 5 more authors.
Journal of Asian Natural Products Research | Year: 2016

A methanol extract of the soft coral Sinularia microspiculata revealed five sterols, including two new compounds. Using combined chromatographic and spectroscopic experiments, the new compounds were found to be 7-oxogorgosterol (1) and 16α-hydroxysarcosterol (2). Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, NOESY, and FT-ICR-MS) and by comparing obtained results to the values indicated in previous studies. Among the isolated compounds, 3 showed weak cytotoxic effects against HL-60 (IC50  =  89.02  ±  9.93 μM) cell line, whereas 5 was weakly active against HL-60 (IC50  =  82.80  ±  13.65 μM) and SK-Mel2 (IC50  =  72.32  ±  1.30 μM) cell lines. © 2016 Informa UK Limited, trading as Taylor & Francis Group


Ban N.K.,Vietnam Academy of Science and Technology | Giang V.H.,Vietnam Academy of Science and Technology | Linh T.M.,Vietnam Academy of Science and Technology | Lien L.Q.,Vietnam Academy of Science and Technology | And 6 more authors.
Phytochemistry Letters | Year: 2013

This work was done as a part of our ongoing projects to catalog the chemical constituents and biological activities of the Morinda species growing in Vietnam. Phytochemical investigations of the methanol extract of Morinda umbellata aerial parts resulted in the isolation of two new 11-noriridoids, umbellatolides A (1) and B (2). Their structures were elucidated by NMR ( 1H NMR, 13C NMR, HSQC, HMBC, 1H-1H COSY, and NOESY) and FTICRMS data. This is the first report of 11-noriridoids from M. umbellata. The cytotoxic activity and protective effect on oxidative stress injury stimulated by H2O2 in murine hepatocyte of 1 and 2 were also evaluated. © 2013 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.


Cuong N.X.,Vietnam Academy of Science and Technology | Vien L.T.,Vietnam Academy of Science and Technology | Hong Hanh T.T.,Vietnam Academy of Science and Technology | Thao N.P.,Vietnam Academy of Science and Technology | And 6 more authors.
Bioorganic and Medicinal Chemistry Letters | Year: 2015

Abstract Seven holostane-type triterpene saponins (1-7), including five new compounds namely cercodemasoides A-E (2-6), were isolated from the sea cucumber Cercodemas anceps. Their structures were elucidated on the basis of spectroscopic evidence including HR ESI MS, ESI MS/MS, 1D and 2D NMR. The cytotoxic effects of isolated compounds were evaluated by SRB method on five human cancer cell lines including Hep-G2 (hepatoma cancer), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma). Compounds 1-7 showed potent cytotoxicity on five tested cancer cell lines with IC50 values ranging from 0.03 ± 0.01 to 7.36 ± 0.46 μM. With respect to the potent cytotoxicity of the isolated saponins, further studies are required to confirm efficacy in vivo and the mechanism of cytotoxic effects. © 2015 Elsevier Ltd.


Vien L.T.,Vietnam Academy of Science and Technology | Ngoan B.T.,Vietnam Academy of Science and Technology | Hanh T.T.H.,Vietnam Academy of Science and Technology | Vinh L.B.,Vietnam Academy of Science and Technology | And 7 more authors.
Journal of Asian Natural Products Research | Year: 2016

Using combined chromatographic separations, two new steroid glycosides namely pentacerosides A (1) and B (2), and four known compounds were isolated from the methanol extract of the starfish Pentaceraster gracilis. Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, ROESY, and FT-ICR-MS) and by comparing obtained results to the literature values. Among the isolated compounds, only maculatoside (5) showed significant cytotoxic effect against Hep-G2 (IC50 = 16.75 ± 0.69 μM) and SK-Mel2 (IC50 = 19.44 ± 1.45 μM) cell lines and moderate effect on KB (IC50 = 36.53 ± 0.78 μM), LNCaP (IC50 = 39.75 ± 3.34 μM), and MCF7 (IC50 = 47.34 ± 7.01 μM) cell lines. © 2016 Informa UK Limited, trading as Taylor & Francis Group


PubMed | Institute of Biotechnology IBT, Institute of Marine Environment and Resources IMER and Vietnam Academy of Science and Technology
Type: Journal Article | Journal: Bioorganic & medicinal chemistry letters | Year: 2015

Seven holostane-type triterpene saponins (1-7), including five new compounds namely cercodemasoides A-E (2-6), were isolated from the sea cucumber Cercodemas anceps. Their structures were elucidated on the basis of spectroscopic evidence including HR ESI MS, ESI MS/MS, 1D and 2D NMR. The cytotoxic effects of isolated compounds were evaluated by SRB method on five human cancer cell lines including Hep-G2 (hepatoma cancer), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma). Compounds 1-7 showed potent cytotoxicity on five tested cancer cell lines with IC50 values ranging from 0.03 0.01 to 7.36 0.46 M. With respect to the potent cytotoxicity of the isolated saponins, further studies are required to confirm efficacy in vivo and the mechanism of cytotoxic effects.

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