Isolation and purification of Australian isolates of the toxic cyanobacteriumMicrocystis aeruginosa Kütz

Bolch, Christopher J. S.; Blackburn, Susan I.

doi:10.1007/bf02186215

Cited by 315 publications

(188 citation statements)

References 13 publications

Supporting

Mentioning

184

Contrasting

Unclassified

Order By: Relevance

“…aeruginosa (CS-564/01) was obtained from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Australian National Algae Culture Collection, Hobart, Australia, and recultured in MLA media (Bolch and Blackburn, 1996). Cultures were subjected to a 16/8 h light/dark cycle at 21 C, in a 500 L, PG50 incubator with a photosynthetic photon flux output of 600 ± 60 mmol m -2 s À1 (Labec, Australia).…”

Section: Cyanobacteriamentioning

confidence: 99%

Hydrophobically-associating cationic polymers as micro-bubble surface modifiers in dissolved air flotation for cyanobacteria cell separation

et al. 2014

View full text Add to dashboard Cite

Cyanobacteria Flotation PosiDAFWater soluble polymers a b s t r a c t Dissolved air flotation (DAF), an effective treatment method for clarifying algae/cyanobacteria-laden water, is highly dependent on coagulation-flocculation. Treatment of algae can be problematic due to unpredictable coagulant demand during blooms. To eliminate the need for coagulation-flocculation, the use of commercial polymers or surfactants to alter bubble charge in DAF has shown potential, termed the PosiDAF process. When using surfactants, poor removal was obtained but good bubble adherence was observed.Conversely, when using polymers, effective cell removal was obtained, attributed to polymer bridging, but polymers did not adhere well to the bubble surface, resulting in a cationic clarified effluent that was indicative of high polymer concentrations. In order to combine the attributes of both polymers (bridging ability) and surfactants (hydrophobicity), in this study, a commercially-available cationic polymer, poly(dimethylaminoethyl methacrylate) (polyDMAEMA), was functionalised with hydrophobic pendant groups of various carbon chain lengths to improve adherence of polymer to a bubble surface. Its performance in PosiDAF was contrasted against commercially-available poly(diallyl dimethyl ammonium chloride) (polyDADMAC). All synthesised polymers used for bubble surface modification were found to produce positively charged bubbles. When applying these cationic micro-bubbles in PosiDAF, in the absence of coagulation-flocculation, cell removals in excess of 90% were obtained, reaching a maximum of 99% cell removal and thus demonstrating process viability. Of the synthesised polymers, the polymer * Corresponding author.E-mail address: r.henderson@unsw.edu.au (R.K. Henderson). 1 Current address: School of Chemical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia.Available online at www.sciencedirect.com ScienceDirect journal h ome page: www.elsevier.com/loca te/watres w a t e r r e s e a r c h 6 1 ( 2 0 1 4 ) 2 5 3 e2 6 2 http://dx

show abstract

Section: Cyanobacteriamentioning

confidence: 99%

Hydrophobically-associating cationic polymers as micro-bubble surface modifiers in dissolved air flotation for cyanobacteria cell separation

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Use of an armored RNA to measure mcyE gene expression New Zealand, by micro-pipetting from a lake water sample and transferred to 24-well plates containing 500 µL MLA medium (Bolch and Blackburn 1996) per well. The samples were incubated at 20 ± 1°C, 100 µEin × m -2 × s -1…”

Section: Rueckert and Carymentioning

confidence: 99%

Use of an armored RNA standard to measure microcystin synthetase E gene expression in toxic Microcystis sp. by reverse‐transcription QPCR

Rueckert

Cary

2009

Limnology & Ocean Methods

View full text Add to dashboard Cite

Microcystin is a secondary metabolic peptide toxin known to cause hepatotoxicosis and carcinogenicity in vertebrates. It is produced by various bloom-forming cyanobacterial species constituting a serious threat to the quality of freshwater reservoirs worldwide. There is an intense interest to understand the biological function of microcystin and the regulatory mechanism behind its biosynthesis in order to develop strategies for freshwater management. To date, changes in toxin production in response to various environmental parameters have been studied using direct toxin analysis. Despite extensive research over the past two decades, the function of microcystin remains poorly understood. In this study, we developed an alternative method to study the regulation of microcystin production in toxic Microcystis sp. (and alternatively in Anabaena sp.) at the level of gene expression targeting microcystin synthetase E (mcyE) transcripts. We developed a durable and ribonuclease-resistant armored RNA standard to monitor for the integrity of all nucleic acid processing steps including extraction, reverse transcription, amplification, and detection. The armored RNA was designed to consist of the mcyE target matrix with a unique internal probe-binding sequence. To validate the efficacy of the method, we conducted a comprehensive survey of mcyE expression profiling in batch cultures of Microcystis sp. during exponential, linear, and stationary growth phase. Our transcriptional analysis indicates a growth-phase-dependent expression of mcyE, with the maximal level of expression observed during mid-log growth. With progressing age of the cultures, mcyE was gradually down-regulated, with expression levels having declined by more than three orders of magnitude during the stationary growth phase.

show abstract

“…In addition, physiological, biochemical, genetic and taxonomic studies of microalgae required axenic (bacteria-free) cultures [4]. Axenic cultures of microalgae are usually prepared by single-cell isolation and density gradient centrifugation, rinsing [5,6], UV irradiation, filtration, treatment with antibiotics [7], and treatment with other germicidal chemicals [8].…”

Section: Introductionmentioning

confidence: 99%

Improved Protocol for the Preparation of Axenic Culture and Adaptation to Heterotrophic Cultivation

Azma¹,

Mohamad²,

Rahim³

et al. 2010

TOBIOTJ

View full text Add to dashboard Cite

Abstract:The effectiveness of various physical and chemical methods for the removal of contaminants from the microalgae, Tetraselmis suecica, culture was investigated. The information obtained was used as the basis for the development of improved protocol for the preparation of axenic culture to be adapted to heterotrophic cultivation. Repeated centrifugation and rinsing effectively removed the free bacterial contaminants from the microalgae culture while sonication helped to loosen up the tightly attached bacterial contaminants on the microalgae cells. Removal of bacterial spores was accomplished using a mixture of two antibiotics, 5 mg/mL vancomycine and 10 mg/mL neomycine. Walne medium formulation with natural seawater was preferred for the enhancement of growth of T. suecica. Adaptation of growth from photoautotrophic to heterotrophic conditions was achieved by the repeated cultivation of photoautotrophic culture with sequential reduction in illumination time, and finally the culture was inoculated into the medium containing 10 g/L glucose, incubated in total darkness to obtain heterotrophic cells. Changes in the morphology and composition of T. suecica cells during the adaptation from photoautotrophic to heterotrophic condition, as examined under Transmission Electron Microscope, were also reported.

show abstract

Isolation and purification of Australian isolates of the toxic cyanobacteriumMicrocystis aeruginosa Kütz

Cited by 315 publications

References 13 publications

Hydrophobically-associating cationic polymers as micro-bubble surface modifiers in dissolved air flotation for cyanobacteria cell separation

Hydrophobically-associating cationic polymers as micro-bubble surface modifiers in dissolved air flotation for cyanobacteria cell separation

Use of an armored RNA standard to measure microcystin synthetase E gene expression in toxic Microcystis sp. by reverse‐transcription QPCR

Improved Protocol for the Preparation of Axenic Culture and Adaptation to Heterotrophic Cultivation

Contact Info

Product

Resources

About