A5021899823- Marine and coastal plant biology
- Marine Biology and Environmental Chemistry
- Seaweed-derived Bioactive Compounds
- Algal biology and biofuel production
- Marine Sponges and Natural Products
- Marine Biology and Ecology Research
- Coral and Marine Ecosystems Studies
- Phosphorus and nutrient management
- Marine Bivalve and Aquaculture Studies
- Echinoderm biology and ecology
- Marine Ecology and Invasive Species
- Aquaculture Nutrition and Growth
- Plant Growth Enhancement Techniques
- Thermochemical Biomass Conversion Processes
- Coal and Its By-products
- Ruminant Nutrition and Digestive Physiology
- Bacterial biofilms and quorum sensing
- Heavy metals in environment
- Aquaculture disease management and microbiota
- Food Industry and Aquatic Biology
- Biodiesel Production and Applications
- Microbial Community Ecology and Physiology
- Crustacean biology and ecology
- Environmental Toxicology and Ecotoxicology
- Microplastics and Plastic Pollution
Precision for Medicine (United States)
2025
South Australian Health and Medical Research Institute
2025
James Cook University
2015-2024
AIMS@JCU
2007-2014
Australian Institute of Marine Science
2006-2007
UNSW Sydney
1997-2006
Heinrich Heine University Düsseldorf
2006
Environmental Earth Sciences
2003
University of Wollongong
2002
Flinders University
2001
Acylated homoserine lactones (AHLs) play a widespread role in intercellular communication among bacteria. The Australian macroalga Delisea pulchra produces secondary metabolites which have structural similarities to AHL molecules. We report here that these inhibited AHL-controlled processes prokaryotes. Our results suggest the interaction between higher organisms and their surface-associated bacteria may be mediated by interference with bacterial regulatory systems.
Summary: Acylated homoserine lactone (AHL)-mediated gene expression controls phenotypes involved in colonization, often specifically of higher organisms, both marine and terrestrial environments. The red alga Delisea pulchra produces halogenated furanones which resemble AHLs structurally show inhibitory activity at ecologically realistic concentrations AHL bioassays. Evidence is presented that displace tritiated OHHL [N-3- (oxohexanoy1)-L-homoserine lactone] from Escherichia coli cells...
In cell‐free Pseudomonas aeruginosa culture supernatants, we identified two compounds capable of activating an N ‐acylhomoserine lactone (AHL) biosensor. Mass spectrometry and NMR spectroscopy revealed that these were not AHLs but the diketopiperazines (DKPs), cyclo(ΔAla‐ l ‐Val) cyclo( ‐Pro‐ ‐Tyr) respectively. These also found in supernatants from Proteus mirabilis , Citrobacter freundii Enterobacter agglomerans [cyclo(ΔAla‐ only]. Although both DKPs absent fluorescens alcaligenes...
Abstract Biomass and lipid productivity, content, quantitative qualitative composition are critical parameters in selecting microalgal species for commercial scale‐up production. This study compares content composition, biomass productivity during logarithmic, late stationary phase of Nannochloropsis sp., Isochrysis Tetraselmis Rhodomonas sp. grown L1‐, f/2‐, K‐medium. Of the tested species, exhibited a 3.9–4.8 g m −2 day −1 any media type, with comparable by when L1‐medium. The dry...
Ruminants are responsible for a large proportion of agricultural greenhouse gas emissions in the form methane. This can be managed. It is global initiative to increase productivity livestock sector meet growing population, but with emphasis on decreasing enteric methane achieve targets. We investigated marine red macroalga (seaweed) Asparagopsis taxiformis as feed ingredient fundamentally eliminate beef cattle fed high grain diet and provide evidence improved production performance. was...
The red macroalgae (seaweed) Asparagopsis spp. has shown to reduce ruminant enteric methane (CH 4 ) production up 99% in vitro . objective of this study was determine the effect taxiformis on CH (g/day per animal), yield (g /kg dry matter intake (DMI)), and intensity ADG); average daily gain (ADG; kg gain/day), feed conversion efficiency (FCE; ADG/kg DMI), carcass meat quality growing beef steers. Twenty-one Angus-Hereford steers were randomly allocated one three treatment groups: 0%...
This study aimed to evaluate the effects of twenty species tropical macroalgae on in vitro fermentation parameters, total gas production (TGP) and methane (CH4) when incubated rumen fluid from cattle fed a low quality roughage diet. Primary biochemical parameters were characterized included proximate, elemental, fatty acid (FAME) analysis. Macroalgae control, decorticated cottonseed meal (DCS), for 72 h, where was continuously monitored. Post-fermentation including CH4 production, pH,...
Asparagopsis taxiformis concentrates halogenated compounds that are known to inhibit cobamide-dependent methanogenesis in vitro and, therefore, has potential mitigate enteric methane production. The present study investigated the effect of on (CH4) production from sheep offered a high-fibre pelleted diet (offered at 1.2 × maintenance) five inclusion levels for 72 days (0% (control), 0.5%, 1%, 2% and 3% organic matter basis as offered). Individual animal CH4 measurements were conducted 21-day...
Livestock feed modification is a viable method for reducing methane emissions from ruminant livestock. Ruminant enteric responsible approximately to 10% of greenhouse gas in Australia. Some species macroalgae have antimethanogenic activity on vitro fermentation. This study used fermentation with rumen inoculum characterise increasing inclusion rates the red macroalga Asparagopsis taxiformis production and digestive efficiency throughout 72-h fermentations. At dose levels ≤1% substrate...
The agricultural production of ruminants is responsible for 24% global methane emissions, contributing 39% emissions this greenhouse gas from the sector. Strategies to mitigate ruminant methanogenesis include use methanogen inhibitors. For example, seaweeds Asparagopsis taxiformis and armata included at low levels in feed cattle sheep inhibit by up 98%, with evidence improvements utilisation efficiency. This has resulted an increasing interest demand these globally. In response, research...
A method is reported for the quantification of 3‐oxoacyl homoserine lactones (3‐oxo AHLs), a major class quorum‐sensing signals found in Gram‐negative bacteria. It based on conversion 3‐oxo AHLs to their pentafluorobenzyloxime derivatives followed by gas chromatography–mass spectrometry (electron capture–negative ion). The used [ 13 C 16 ]‐ N ‐3‐oxo‐dodecanoyl lactone ([ ]‐OdDHL) as internal standard, and its validity was tested spiking supernatant cell fractions with three levels AHLs, i.e....
In this study the antifouling activity was investigated of a series chemically related, halogenated furanones isolated from Delisea pulchra (Greville) Montagne, red alga which is rarely fouled in field. The metabolites were tested laboratory assays against representatives three major groups fouling organisms, barnacle Balanus amphitrite amphitirite Darwin, macroalga Ulva lactuca Linnaeus and marine bacterium (strain SW 8). Settlement cyprid larvae strongly inhibited, with an EC50 < 25...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 306:87-101 (2006) - doi:10.3354/meps306087 Chemical defence against bacteria in red alga Asparagopsis armata: linking structure with function N. A. Paul1,*, R. de Nys2, P. D. Steinberg1 1School of Biological, Earth & Environmental Sciences, and Centre for Biofouling Bio-Innovation, University New South Wales,...
This paper examines attachment point theory in detail by testing the fouling of several groups to a microtextured matrix. Static bioassays were conducted on polycarbonate plates with nine equal regions, comprising eight scales microtexture (4–512 µm) and one untextured region. The microtextures examined continuous sinusoidal ridges troughs defined height width. Attachment over was for diatom Amphora sp., green alga Ulva rigida, red Centroceras clavulatum, serpulid tube worm Hydroides elegans...
AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsSpecials 15:233-246 (1998) - doi:10.3354/ame015233 Chemical mediation of bacterial surface colonisation by secondary metabolites from red alga Delisea pulchra Ria Maximilien1, Rocky de Nys1,3, Carola Holmström2,3, Lone Gram4, Michael Givskov5, Katherine Crass1,3, Staffan Kjelleberg2,3, Peter D. Steinberg1,3,* 1School Biological...
ABSTRACT Expression of luminescence in the Penaeus monodon pathogen Vibrio harveyi is regulated by an intercellular quorum sensing mechanism involving synthesis and detection two signaling molecules, one which N -hydroxy butanoyl- l -homoserine lactone other uncharacterized. Indirect evidence has suggested that virulence, associated with a toxic extracellular protein, V. are coregulated. In this study effects acylated homoserine antagonist produced marine alga Delisea pulchra on toxin...
Abstract This paper explores diatom attachment to a range of laser etched polyimide surfaces directly test ‘attachment point theory’. Static bioassays were conducted on microtextured using four species, Fallacia carpentariae, Nitzschia cf. paleacea, Amphora sp. and Navicula jeffreyi with cell sizes ranging from 1 – 14 μm. The polyimides modelled natural fouling resistant bivalve had wavelengths above, below at the same scale as sizes. Diatoms attached in significantly higher numbers...
Abstract We investigated the potential of seaweeds as feedstock for oil‐based products, and our results support macroalgae (seaweeds) a biomass source bioproducts including biodiesel. Not only do several have high total lipid content above 10% dry weight, but in brown alga Spatoglossum macrodontum 50% these lipids are form extractable fatty acids. S. had highest acid (57.40 mg g −1 dw) profile rich saturated acids with C18:1, which is suitable biofuel feedstock. Similarly, green seaweed...