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Your search keyword '"Beuzenberg, Veronica"' showing total 41 results
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41 results on '"Beuzenberg, Veronica"'

10. Isolation and identification of (44- R,S)-44,55-dihydroxyyessotoxin from Protoceratium reticulatum, and its occurrence in extracts of shellfish from New Zealand, Norway and Canada

Author

Finch, Sarah C., Wilkins, Alistair L., Hawkes, Allan D., Jensen, Dwayne J., MacKenzie, A. Lincoln, Beuzenberg, Veronica, Quilliam, Michael A., Olseng, Christine D., Samdal, Ingunn A., Aasen, John, Selwood, Andrew I., Cooney, Janine M., Sandvik, Morten, and Miles, Christopher O.

Published
2005
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23. Optimising conditions for growth and xanthophyll production in continuous culture of Tisochrysis lutea using photobioreactor arrays and central composite design experiments.

Author

Beuzenberg, Veronica, Goodwin, Eric O., Puddick, Jonathan, Romanazzi, Donato, Adams, Serean L., and Packer, Michael A.

Subjects
*XANTHOPHYLLS, *MICROALGAE, *PHOTOBIOREACTORS, *XANTHINE, *BIOSYNTHESIS, *SUSTAINABILITY
Abstract

The production of valuable metabolites from microalgae represents a potentially sustainable source of a range of products that can be difficult to synthesise directly. Microalgae respond to the dynamic and often subtly shifting growth environment in a complex way. The optimal conditions for growth can be quite different to those needed for optimal product generation, depending on the nature of the biosynthesis of that product. This is especially so for secondary metabolites. A combination of a multi-vessel photobioreactor array, where certain growth conditions can be monitored and controlled precisely together with an experimental design matrix has been used to determine the optimal combination of temperature, irradiance and pH for a group of xanthophylls including fucoxanthin in the algaeTisochrysis luteain continuous culture. Continuous culture as a mode is more suited for industrial production than batch mode in which the media constituents and algal population change dramatically over time. The central composite design experiment matrix has a range of set values for each parameter being investigated that bracket the optimal conditions. The three parameters investigated in this work (temperature, irradiance and pH) are major factors influencing algal growth. The method can be applied to other parameters that might affect growth or might affect production of a metabolite of interest, such as a nutrient level. The combined approach has been used previously to indicate optimal growth conditions for biomass generation and this work is one of the first to apply it to the generation of an algal product of interest. [ABSTRACT FROM PUBLISHER]

Published
2017
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24. Brevisulcatic Acids, Marine Ladder-Frame Polyethers from the Red Tide Dinoflagellate Karenia brevisulcata in New Zealand

Author

Suzuki, Rina, primary, Irie, Raku, additional, Harntaweesup, Yanit, additional, Tachibana, Kazuo, additional, Holland, Patrick T., additional, Harwood, D. Tim, additional, Shi, Feng, additional, Beuzenberg, Veronica, additional, Itoh, Yoshiyuki, additional, Pascal, Steven, additional, Edwards, Patrick J. B., additional, and Satake, Masayuki, additional

Published
2014
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26. Novel toxins produced by the dinoflagellate Karenia brevisulcata

Author

Holland, Patrick T., primary, Shi, Feng, additional, Satake, Masayuki, additional, Hamamoto, Yuka, additional, Ito, Emiko, additional, Beuzenberg, Veronica, additional, McNabb, Paul, additional, Munday, Rex, additional, Briggs, Lyn, additional, Truman, Penelope, additional, Gooneratne, Ravi, additional, Edwards, Patrick, additional, and Pascal, Steven M., additional

Published
2012
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27. Optimising conditions for growth and xanthophyll production in continuous culture of Tisochrysis luteausing photobioreactor arrays and central composite design experiments

Author

Beuzenberg, Veronica, Goodwin, Eric O., Puddick, Jonathan, Romanazzi, Donato, Adams, Serean L., and Packer, Michael A.

Abstract

ABSTRACTThe production of valuable metabolites from microalgae represents a potentially sustainable source of a range of products that can be difficult to synthesise directly. Microalgae respond to the dynamic and often subtly shifting growth environment in a complex way. The optimal conditions for growth can be quite different to those needed for optimal product generation, depending on the nature of the biosynthesis of that product. This is especially so for secondary metabolites. A combination of a multi-vessel photobioreactor array, where certain growth conditions can be monitored and controlled precisely together with an experimental design matrix has been used to determine the optimal combination of temperature, irradiance and pH for a group of xanthophylls including fucoxanthin in the algae Tisochrysis luteain continuous culture. Continuous culture as a mode is more suited for industrial production than batch mode in which the media constituents and algal population change dramatically over time. The central composite design experiment matrix has a range of set values for each parameter being investigated that bracket the optimal conditions. The three parameters investigated in this work (temperature, irradiance and pH) are major factors influencing algal growth. The method can be applied to other parameters that might affect growth or might affect production of a metabolite of interest, such as a nutrient level. The combined approach has been used previously to indicate optimal growth conditions for biomass generation and this work is one of the first to apply it to the generation of an algal product of interest.

Published
2017
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35. Identification of Pectenotoxin-11 as 34S-Hydroxypectenotoxin-2, a New Pectenotoxin Analogue in the Toxic Dinoflagellate Dinophysis acuta from New Zealand

Author

Suzuki, Toshiyuki, primary, Walter, John A., additional, LeBlanc, Patricia, additional, MacKinnon, Shawna, additional, Miles, Christopher O., additional, Wilkins, Alistair L., additional, Munday, Rex, additional, Beuzenberg, Veronica, additional, MacKenzie, A. Lincoln, additional, Jensen, Dwayne J., additional, Cooney, Janine M., additional, and Quilliam, Michael A., additional

Published
2006
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39. Measuring the influence of nutrients and river water on the photosynthetic efficiency of Didymosphenia geminatausing pulse amplitude modulated fluorometry

Author

Biessy, Laura, Atalah, Javier, Beuzenberg, Veronica, Kuhajek, Jeanne, and Wood, Susanna A.

Abstract

Over the past three decades the freshwater diatom Didymosphenia geminata(Lyngbye) M. Schmidt has expanded its range globally. In some rivers D. geminatahas become invasive, forming expansive and thick polysaccharide-dominated mats. Techniques to maintain and study D. geminatain the laboratory are limited. In this study, a 96-well plate format assay using pulse amplitude modulated (PAM) fluorometry was developed to study D. geminataunder controlled conditions. The PAM assay and morphological assessments were used to investigate the addition of sodium nitrate (NaNO3) to a previously developed D. geminata-specific growth medium (Didymo Medium; DM). Addition of low concentrations (ca. 0.003–0.018 µM) enhanced cell survival and health. Central-composite design (CCD) experiments coupled with response surface methodology were then used to investigate optimal concentrations of six key chemicals in DM (magnesium sulphate, calcium chloride, mono-potassium phosphate, sodium metasilicate pentahydrate, ferric sodium ethylenediaminetetraacetic acid (EDTA) and NaNO3). An optimised DM recipe is provided. The PAM assay was also used to analyse the influence of maintaining D. geminatacells in river waters sourced from locations with and without the diatom. A NaNO3spiking experiment was undertaken using water from one location. The maximum quantum yields of cells maintained in all river waters remained relatively constant and higher than those maintained in DM or Milli-Q water for the seven day test period. The results of the NaNO3river water spiking experiment provided contrasting results to the culture medium trials, with minimal impact on photosynthetic efficiency. These data, coupled with the results of the CCD experiment, suggest complex interactions among nutrients that have varying effects on D. geminatacell health. Together with microscopical observations, the 96-well plate PAM assay provides a useful tool for improving knowledge of D. geminatabiology and growth requirements.

Published
2016
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41. Isolation and identification of a cis-C8-diol-ester of okadaic acid from Dinophysis acuta in New Zealand

Author

Miles, Christopher O., Wilkins, Alistair L., Hawkes, Allan D., Jensen, Dwayne J., Cooney, Janine M., Larsen, Kristofer, Petersen, Dirk, Rise, Frode, Beuzenberg, Veronica, and Lincoln MacKenzie, A.

Subjects
*SPECTRUM analysis, *NUCLEAR magnetic resonance, *MASS spectrometry
Abstract

Abstract: A cis-isomer of a C8-diol ester of okadaic acid (1) was isolated during large-scale purification of pectenotoxins (PTXs) from extracts of Dinophysis acuta collected from the west coast of South Island, New Zealand. The compound was identified by NMR spectroscopic and liquid chromatography-mass spectrometry (LC-MS) studies, and is the first reported cis-isomer of an okadaic acid C8-diol-ester identified in Dinophysis. The more abundant trans-C8-diol ester of okadaic acid (2) isolated from the same Dinophysis extract was rapidly hydrolyzed to okadaic acid in vitro by the supernatant from green-lipped mussel hepatopancreas. [Copyright &y& Elsevier]

Published
2006
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