Made available in DSpace on 2014-06-11T19:31:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-09Bitstream added on 2014-06-13T18:41:23Z : No. of bitstreams: 1 cupertino_fb_dr_araiq.pdf: 10818363 bytes, checksum: 34f272c80573854af968c2e298ba0e61 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho descreve a caracterização funcional de alguns fatores de transcrição possivelmente envolvidos na regulação do metabolismo do glicogênio no fungo filamentoso Neurospora crassa. Em uma análise sistemática realizada com 69 linhagens mutantes em genes codificadores para fatores de transcrição, foram identificadas e selecionadas sete linhagens que apresentaram perfis diferentes de acúmulo de glicogênio, em relação à linhagem selvagem, tanto durante o crescimento vegetativo (30°C) como no estresse térmico (45°C). Com o objetivo de verificar o envolvimento dos fatores de transcrição selecionados na expressão dos genes gsn (glicogênio sintase) e gpn (glicogênio fosforilase), experimentos de Northern blot foram realizados e revelaram variações ao nível transcricional em algumas linhagens. A análise por Blast revelou que alguns fatores de transcrição haviam sido previamente estudados em N. crassa (CSP-1, RCO-1, NIT2) ou em outros organismos (PacC, FlbC, Fkh1) e participam na regulação de diferentes processos biológicos. O fator de transcrição PACC e a influência do pH externo sobre a regulação do metabolismo do glicogênio foram investigados mais detalhadamente neste trabalho. Os resultados mostraram que na linhagem selvagem o acúmulo de glicogênio e a expressão do gene gsn foram reprimidos em condições de pH alcalino, enquanto que o gene pacC foi superexpresso nesta condição. A linhagem mutante pacCKO mostrou perder a regulação sobre o acúmulo de glicogênio e expressão do gene gsn, tanto durante o crescimento em pH fisiológico (5,8) como alcalino (7,8). A análise de ligação DNA-proteína mostrou que a proteína PACC de N. crassa recombinante produzida em E. coli foi capaz de se ligar ao motif de DNA para a proteína PACC, presente na região promotora do gene gsn... / This work describes the functional characterization of transcription factors likely involved in glycogen metabolism regulation in the filamentous fungus Neurospora crassa. In a systematic analysis performed with 69 strains knocked-out in genes encoding transcription factors, seven strains were identified and selected by presenting profiles of glycogen accumulation different from that existent in the wild-type strain during vegetative growth (30°C) and under heat stress (45°C). In order to verify the involvement of the selected transcription factors in regulation of gsn (codes for glycogen synthase) and gpn (codes for glycogen phosphorylase) genes, Northern blot assays were performed. Differences in gene expression were observed in some strains compared to the wild-type strain. Blast analysis showed that transcription factors have been previously studied either in N. crassa (CSP-1, RCO-1, NIT2) or in other organisms (PacC, FlbC, Fkh1) participating in the regulation of different biological processes. The transcription factor PACC and the influence of the external pH under the regulation of the glycogen metabolism were further investigated. The results showed that in the wild-type strain the glycogen content and the gsn gene expression were repressed under alkaline conditions, while the pacC gene was overexpressed in this condition. The pacCKO strain showed impairments in the glycogen accumulation and gsn gene expression under normal pH (5.8) and alkaline (7.8) conditions. Protein-DNA binding analysis showed that N. crassa PACC recombinant protein produced in E. coli cells was able to bind to the pacC motif present in the gsn promoter. Binding specificity was confirmed by competition assays using an oligonucleotide containing the DNA motif and by binding to a DNA fragment containing the motif mutated by site-directed mutagenesis... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:31:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-24Bitstream added on 2014-06-13T18:41:23Z : No. of bitstreams: 1 goncalves_rcr_dr_araiq.pdf: 2969131 bytes, checksum: 2ec7f5373394bf23e94222f4356154f3 (MD5) / Outros / Do fungo Aspergillus nidulans foi isolado um mutante que apresenta producao aumentada do pigmento melanina. Este pigmento, formado pela polimerizacao oxidativa de compostos fenolicos e/ou indolicos, pode estar presente na parede celular ou no meio de cultura. Embora nao seja essencial para o crescimento dos fungos, a melanizacao parece aumentar a capacidade de sobrevivencia das especies em condicoes desfavoraveis, fornecendo protecao contra radiacao UV, altas temperaturas, enzimas hidroliticas, metais pesados e agentes oxidantes. A obtencao deste pigmento, na forma pura, tem despertado interesse biotecnologico devido a sua utilizacao em formulacoes cosmeticas, principalmente pela sua propriedade fotoprotetora e antioxidante. Tendo em vista o potencial farmacologico do pigmento melanina, este trabalho tem como objetivos fazer a caracterizacao estrutural e funcional do pigmento extraido do fungo A. nidulans. Os resultados de espectrometria de massas indicam que a estrutura da melanina do fungo A. nidulans e composta de duas grandes unidades, representadas pelos fragmentos de massas moleculares igual a 573 e 550, com grupamentos diidroxindol e aneis pirrolicos substituidos. Os ensaios de citotoxicidade mostram que a melanina extraida do fungo A. nidulans nao causa danos significativos aos componentes celulares, tanto antes como pos metabolizacao. Os ensaios de mutagenicidade sugerem que a melanina nao apresenta propriedades mutagenicas para as linhagens TA 97a, TA 98, TA 100 e TA 102 de Salmonella thyphimurium. No teste antimicrobiano, observase que a melanina do fungo nao apresenta potencial como antibacteriano frente a Staphylococcus aureus, Escherichia coli e Enterococcus faecalis, quando comparadas com as substancias de referencia, ampicilina e cloranfenicol. Quanto... / A mutant that presents increased production of the melanin pigment was isolated from the Aspergillus nidulans fungus. This pigment, formed by the oxidative polymerization of phenolic and/or indolic compounds, can be present in the cellular wall or culture medium. Although it is not essential for the fungal growth, melanization seems to increase the survival capacity of the species in unfavorable conditions, supplying protections against UV radiation, high temperatures, hydrolytic enzymes, heavy metals and oxidants agents. The attainment of this pigment, in its pure form, has taken biotechnological interest due to its use in cosmetic formulations, mainly for its photoprotector and antioxidant property .Considering the pharmacological potential of the melanin pigment, this study aims to make the structural and functional characterization of the pigment extracted from A. nidulans fungus. The results of mass spectrometry indicate that the melanin structure of the A. nidulans fungus is composed of two large units, represented by the fragments of molecular mass equal to 573 and 550, with dihydroxyindole groups and substituted pyrrolic rings. The cytotoxicity assays have shown that the melanin extracted from the A. nidulans fungus does not cause significant damages to the cellular components, before and after metabolization. The mutagenicity assays suggest that the melanin does not present mutagenic properties for the strains TA 97a, TA 98, TA 100 and TA 102 of Salmonella thyphimurium. In the antimicrobial test, it is observed that the fungal melanin does not present antibacterial potential facing Staphylococcus aureus, Enterococcus faecalis and Escherichia coli, when compared to the reference substances, ampicilin and cloranphenicol. Regarding the immunomodulatory activity, it was verified that the melanin does not stimulate NO release... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:31:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-26Bitstream added on 2014-06-13T19:19:53Z : No. of bitstreams: 1 henao_dmo_dr_araiq.pdf: 3174604 bytes, checksum: 225a4ef35be95bb55bec3d13550ee90d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A bactéria acidofílica Acidithiobacillus ferrooxidans é encontrada em ambientes inorgânicos e ácidos tais como depósitos minerais e drenagem ácida de minas, sendo a principal bactéria envolvida na biolixiviação, um processo pelo qual o metabolismo microbiano causa a solubilização do metal contido em minérios que possuam sulfetos metálicos. A adesão da bactéria à superfície do mineral com a subseqüente formação de biofilme é um pré-requisito para a dissolução do sulfeto metálico. Apesar de existirem pesquisas sobre a biogênese, a bioquímica e a regulação da formação de biofilme, o processo primário de adesão e os genes que participam destes processos têm sido pouco estudados nessa espécie bacteriana. O objetivo do presente trabalho foi analisar a adesão e o reconhecimento de grupos tióis na linhagem A. ferrooxidans LR em presença do sulfeto de cobre calcopirita (CuFeS2). Para este fim, foram selecionados onze genes descritos no genoma de A. ferrooxidans ATCC 23270, disponibilizado pela TIGR. Os genes selecionados para este trabalho são: cluster tad (tadA, tadB e tadC) envolvidos na formação de pilus e fimbrias; genes que codificam pilinas do tipo IV; genes pertencentes ao cluster Fe-S e o gene msrA que codifica uma metionina -Ssulfóxido redutase. A análise da expressão destes genes foi realizada por PCR em tempo real. Foi feita uma análise de bioinformática com o objetivo de conhecer o grau de conservação das seqüências das proteínas codificadas pelos genes e a busca de domínios conservados nessas proteínas. Além disso, foi clonada, purificada e caracterizada por métodos biofísicos uma proteína ligante de cluster Fe-S, com o objetivo de avaliá-la futuramente no processo global de biolixiviação. Os resultados de expressão a partir de PCR em tempo real de células livres e aderidas incubadas em presença de calcopirita mostraram... / The acidophilic bacterium Acidithiobacillus ferrooxidans is capable of causing dissolution of metals have been identified in acid mine water and mineral processing plants. Usually this microorganism is found in those places and they have been widely studied in bacterial oxidation and lixiviation in which use inorganic electron donors and fixed carbon dioxide. For this reason has been utilized for enhancing the extraction rates of metals in the ores. The mineralassociated bacteria, adhesion and biofilm formation are critical steps for colonization and subsequent mineral solubilization. Despite research of biogenesis, biochemistry and regulation of biofilm formation has been reported, adhesion process through pilus assembly mechanisms is not studied in this bacterium in spite of related genes involved in the formation of a type IV pilus and tight adherence were identified in thus genome. The objective of this work was to analysis tight adherence, type IV pilus and possibly thiol recognition cluster Fe-S genes expression for time real PCR in planktonic and adhered cells of A. ferrooxidans strain LR incubated in the presence of chalcopyrite. As well, In Silico analysis was realized for genes selected to conservation and conserved domains research. Finally, the Fe-S cluster-binding protein codified by locus Afe_0551 was cloned and expresses to characterize for spectroscopic methods. The results of gene expression revealed to level expression differences in planktonic and adhered cells incubated with chalcopyrite. The genes were unaltered or repressed after 24 h of incubation, however, the expression changed to induction after 20 dyes. Probably, the process of adhesion in first hours of incubation is favored. In the other hand, the Fe-S cluster-binding protein codified by locus Afe_0551 showed high thermal resistance and stability in widen pH range. Far-UV CD measurements showed a high structure... (Complete abstract click electronic access below)

Detta arbete är en beställning från Vidilab AB som går ut på att kartlägga resistensmekanismer hos nematoder samt ta fram en resistensassay. Beställningen grundar sig i problematiken kring dagens metoder för resistensbestämning, som går ut på att analysera förekomsten av ägg i avföringen från betande djur innan respektive efter avmaskning. Vidilab efterlyser en molekylär diagnostikmetod för resistensbestämning innan boskapsdjuren behandlas med anthelmintika. Som avgränsning har projektet riktat in sig på resistensmekanismer hos nematoden Haemonchus contortus som i första hand parasiterar får. I projektet har i huvudsak förslag på tre tekniker tagits fram som skulle kunna användas för resistensbestämning hos H. contortus. Dessa tre metoder är allelspecifik PCR, RT-PCR och MALDI-TOF. Slutsatsen i detta projekt är att samtliga av dessa tre metoder har potential som molekylär diagnostikmetod. Dock krävs mer forskning kring H. contortus resistensmekanismer, storskalig sekvensering samt kartläggning av transkriptom och proteomikstudier innan teknikerna kan appliceras som standardiserade diagnostikmetoder.

This thesis reports the development of acid-operating microbial fuel cells (MFCs) for the investigation of elevated electrical conductivity and resulting enhanced bioelectricity generation. This project describes the use of extremophile microorganisms as the biological material in MFCs, for the investigation of low internal resistance biological fuel cells. In particular, this thesis focuses on BPV (biological photovoltaic) cells, a type of MFC that utilises autotrophic biological material, which relies on oxygenic photosynthesis and hence simply requires water as the electron donor (unlike traditional MFCs, which are dependent of an organic substrate feed). Novel reactor designs based on acidophilic and metallotolerant microorganisms, studied using electrochemical techniques, are reported for the first time. The novel strategy consists in the adoption of very low pH and elevated heavy metal concentration levels for biological fuel cell operation, which is possible due to the choice of suitable extremophile microorganisms that are able to thrive under such severe physicochemical conditions. In order to support the analysis of the subject MFCs, a series of electrochemical and fluorescence techniques were employed. Chapter 3 reports the study of standard BPV cells, focusing on classic cell configuration and choice of biological material. BPV cells based on the standard prokaryotic and eukaryotic strains Synechococcus elongatus and Chlorella vulgaris, respectively, were built and electrochemically characterised by means of polarisation curves and continuous power output monitorisation. Subsequently, a study on the potential conditioning of BPV cells was conducted using Pulse Amplitude Modulation (PAM) Fluorimetry; it is the first documented observation of short-term electrolytic potential conditioning effects on photosynthetic efficiency and associated parameters. The work in chapters 4 and 5 explores the extent to which acidophiles may be used as the biological material in MFCs. A search to find a set of naturally-occurring, metallotolerant acidophiles is undertaken throughout the Rio Tinto ecosystem, selected for its unique extreme physicochemical nature and reported extremophile presence. Chapter 4 informs about the physicochemical characterisation of the chosen sampling points, describing the evolution of pH, electrical conductivity, heavy metal concentration, ferric/ferrous ion balance and dissolved oxygen throughout a natural year, in order to identify the sites with the hardest physicochemical conditions. Finally, chapter 5 investigates the presence of living microorganisms in the sampled sites, enabling the identification of the best location for the purpose of this study. A tailored sediment cell was built and tested in situ (for the first time in an extremophilic environment), and compared to the electrical performance of a novel BPV cell based on commercially-available photosynthetic acidophile Dunaliella acidophila.

In the human body, the main function of the healthy thyroid gland is the regulation of the metabolism and hormone production. Included in the thyroid are organized structured and uniformly shaped follicles ranging from 50-500 μm in diameter. Pathologies lead to morphological changes of these follicles, affecting the density and size, but can also lead to an absence. In this study optical coherence tomography (OCT) was used to examine pathological thyroid tissue by extracting structural information of the follicles from image segmentation. However, OCT images usually include a high amount of speckle noise which affects the segmentation outcome. Due to that, the OCT images need to be improved. The aim of this thesis was to investigate the appropriate filtering methods to enhance the images and thus improve the segmentation outcome. The images of pathological thyroid tissues with a size of 0:5-1 cm where scanned by a spectral domain OCT system (Telesto II, Thorlabs GmbH, Germany) using a center wavelength of 1300nm. The obtained 2D and 3D images were saved as .oct file as well as implemented and visualized in a MATLAB graphical user interface (GUI) for further processing. For image improvement, four filtering enhancement methods were applied to the 2D images such as the enhanced resolution imaging (ERI), adaptive Wiener filter, discrete wavelet transform (DWT) and multi-frame wavelet transform (WT). The processed images were further converted to grayscale and binary images for intensity-based segmentation. The output of all methods were compared and evaluated using signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), enhanced number of looks (ENL), edge profiles and outcome of the segmented images. It was demonstrated that the complex DWT (cDWT) with a higher threshold and the multi-frame WT using the haar wavelet showed enhanced results over the other filtering methods. The computed SNR could be increased up to 52% and the ENL value up to 4802%, applying the multi-frame WT, while the CNR could be increased up to 106% for cDWT. The lowest obtained gradient was equal to an intensity decrease of -61% and -68% for multi-frame WT and cDWT, respectively. The filtering method could increase the smoothness of the image while the edge sharpness could be kept. The segmentation could detect both small and large follicles. ERI did not show any improvement in the segmentation but could enhance the structural detail of the image. Larger neighbourhoods of the adaptive Wiener filter showed a highly blurred image and led to merged follicles in the image segmentation. The wavelet filters DWT and multi-frame WT gave most satisfying results since high and low frequencies were divided into subbands, where individual information on vertical, horizontal and diagonal edges was stored. Applied cDWT had an even higher amount of subbands, so that more information on signal and speckle noise could be specified. Due to this fact, it was possible to achieve a decreased noise level while edge sharpness where maintained. Using a multi-frame image an increased SNR was obtained, as the intensity information stayed constant over the individual frames while the noise information changed. Wavelet based filtering showed higher improved results in comparison to the adaptive Wiener filter or the ERI in the 2D domain. By applying filtering methods in higher dimensions such as 3D or even 4D, better results in noise reduction are expected. Improved settings for the individual filtering methods as well as enhancement in segmentation are part of the future work.

acase@tulane.edu / 1 / Alejandra E. Marks

A novel metal-inducible and amplifiable metallothionein (MT) expression system, pNK, was firstly optimised and characterised for the production of a reporter protein, human growth hormone (hGH) in a suspension CHO cell line grown in a serum-free media. The pNK-based hGH production was demonstrated in cadmium-free condition under various fermentation modes (batch, fed-batch and perfusion) and scales (flask to bench-top bioreactor). Improvement of specific productivity of recombinant protein from pNK was shown to be possible by addition of butyrate or substrate substitution of glutamine by glutamate. Combination of fed-batch and butyrate addition strategies resulted in more than one gram per litre of hGH being obtained from the pNK expression system in a bioreactor. In the second part of the project, based on a statistical approach suggested by Plackett-Burman (P-B), a chemically-defined and protein-free medium, named Super-CHO protein-free (SPF), was developed to support a Super-CHO cell line, C2.8-325, to grow as a single-cell suspension culture with comparable growth rate and viable cell number as observed in a commercial medium containing undefined additives. Using Dulbecco's Modified Eagle's Medium/Ham's F12 1:1 mixture (DMEM/F12) as the basal medium, a P-B design matrix screened 10 nutritional components. Components shown potentially beneficial for cell growth rate and viable cell number were supplemented to DMEM/F12 to formulate the SPF medium. Finally, the pNK expression system and the Super-CHO cell line were applied simultaneously in an attempt to express a humanised anti-CD48 monoclonal antibody (MAb), IgG1-N2A (N2A-MAb). This aimed to test C2.8-SPF grown in newly developed SPF medium for transfection, clone development and recombinant protein production. A stable and N2A-MAb expressing C2.8-SPF cell line was successfully constructed, and N2A MAb expression was subsequently amplified and demonstrated in various cultivation scales (flask and bioreactor). This project demonstrated that the novel metal-inducible and - amplifiable mammalian expression system, pNK, and the novel mammalian host cell-line, Super-CHO C2.8-SPF, capable of growing as a single-cell suspension culture in a chemically-defined protein-free medium, SPF, could be utilised in combination to provide a new, low-cost, and regulatory-compliant recombinant protein expression platform, suitable for the biopharmaceutical industry to use in the manufacture of therapeutic recombinant proteins.

<p>The scope for this work was to develop rapid assays for enumerating microorganisms on gels, and to test whether fouling of gel surfaces is principally different from that of solid substrata. For this purpose, a standard set of different gels were selected, based on biocompatibility, polymer charge and gel strength. </p><p>Bacterial adhesion to gels could be conveniently enumerated by first staining with SYBR Green I nucleic acid gel strain. Images were then collected using a confocal scanning laser microscope, followed by image analysis to determine the percent coverage of bacteria. Diatom adhesion could be qualified using a fluorescence scanner recording the fluorescent chlorophyll, showing a clear correlation between average fluorescence signals and cell density determined by counting. This method was successfully tested on glass, gels, a painted surface and an antifouling coated surface.</p><p>Adhesion of the marine bacterium Pseudomonas sp. NCIMB 2021on gels decreased at higher shear rates. At low shear rates, adhesion varied significantly between different gels in the following descending order: alginate > agarose > chitosan > PVA-SbQ. Lowest cell coverage at all shear rates was recorded on the most hydrophobic gel, PVA-SbQ. Earlier work has shown that this organism adhere better to solid hydrophobic than solid hydrophilic surfaces. Thus, other properties than the surface free energy may be more important for bacterial adhesion to the gels. </p><p>The marine diatom Amphora coffeaeformis was applied in the different adhesion arrays under different shear conditions. At high shear, cells adhered better to highly ionic polymer gels alginate and chitosan than to the low charge polymer gels agarose and PVA-SbQ. At very low shear, A. coeffeaeformis developed a film even on agarose equivalent to that on the charged polymer gels. Adhesion to PVA-SbQ remained low at all shear rates. As observed for solid substrate, low charge density led to reduced attachment. </p><p>Settlement of Balanus amphitrite cypris larvae was tested at different polymer concentrations of the hydrogels. All gels inhibited cypris settlement compared to solid polystyrene controls. Gels consisting of 2.5% PVA-SbQ or 0.5% agarose showed the most promising antifouling properties. In all gel experiments, most of the non-settled larvae were able to settle when transferred and offered a suitable solid substratum. Results indicated that the gel strength was an important factor for cyprid settlement on gels, while the surface wettability seemed to be of minor importance.</p><p>A few preliminary field experiments were carried out. These tests suggested that marine bacterial biofilm development is more readily on glass than on a PVA-SbQ gel surface, in accordance with monoculture lab experiments. However, similar amounts of photosynthetic organisms adhered to gels of agorose, alginate, chitosan and PVA-SbQ tested in an outdoor seawater basin during spring bloom. Finally, barnacle settlement was delayed on PVA-SbQ gels exposed in the open sea. After incubation for a full summer season, even those gels became as covered with marine fouling organisms as any other non-toxic surface. </p><p>In conclusion, no universal antifouling effects of hydrogels were found. However, this work suggests that both adhesion of a bacterium and settlement of barnacle cypris larvae on gel surfaces may be principally different from solid substrata. Diatom adhesion, on the other hand, was lower on gels with a low charge density, as observed for solid substrata. In general, the most hydrophobic gel, PVA-SbQ, was the least attractive surface for all three organisms. </p>

<p>Brown seaweeds lack lignin and have a low cellulose content. Thus, seaweeds should be an easier material for biological degradation than land plants. However, seaweeds have a complex composition, and complete degradation of the material necessitates the presence of microorganisms with a broad substrate range. During anaerobic degradation of organic material, energy carriers such as methane and ethanol may be produced. This is a study of two particular species of brown seaweeds; <i>Laminaria hyperborea</i> and <i>Ascophyllum nodosum</i>, which are the most abundant Norwegian species and also the two species that are commercially harvested in Norway.</p><p>Most of the degradation studies were carried out in batch systems at pH 7 and at 35 °C. The digestion pattern of the seaweeds were studied by measuring gas production, alginate lyase activity, remaining alginate, the concentrations of uronic acids, VS, COD, mannitol, organic acids and polyphenols. NIR spectroscopy was applied as a new method for alginate quantification. Ethanol production was carried out at 30 °C at different pH, both in batch and continuous cultures. Gas production and concentrations of mannitol, laminaran, ethanol and organic acids were measured.</p><p>Methane is the end product of a mixed microbial community. However, it is the initial steps of hydrolysis and acidogenesis that are specific for the raw material. Alginate forms the major structural component of brown algae, and its degradation is catalysed by alginate lyases. Polyphenols proved to be the most important limiting factor in the biodegradation: the content of polyphenols was much higher in <i>A. nodosum</i> than <i>L. hyperborea</i>, and this led to a reduced biodegradability of <i>A. nodosum</i>. However, when the polyphenols were fixed with formaldehyde, this seaweed was also readily degraded. Manipulation of the content of polyphenols in <i>L. hyperborea</i> gave similar results. This toxic effect was probably caused by direct inhibition of the microbes, especially the methanogenic bacteria, and complexation reactions with algal material and enzymes. Generally, the guluronate content of the remaining alginate increased during biodegradation, probably due to the Ca-linked guluronate junction zones less accessible for alginate lyase. The main organic product of the acidogenesis was acetate, which was easily converted to methane. In this study, it was not attempted to optimise the methane yield.</p><p>Ethanol is an intermediate in the complete digestion of organic material and is produced by specific microbial strains. Thus, ethanol production should take place under controlled conditions to prevent contamination problems. The complex composition of seaweeds makes it a difficult substrate to ferment to ethanol by one or a few strains of microbes. In this work, laminaran and mannitol extracted from <i>L hyperborea</i> fronds were used as substrate for ethanol production. <i>A bacterium</i>, <i>Zymobacter palmae</i>, was able to produce ethanol from mannitol, but could not utilise laminaran. However, the yeast <i>Pichia angophorae</i> was able to produce ethanol from both substrates simultaneously. Some supply of oxygen was necessary for the fermentation of mannitol, while a too high aeration resulted in the production of organic acids.</p><p>Thus, it has been shown that both methane and ethanol can be produced from brown seaweeds. However, an optimisation of the processes will be necessary. Energy production from seaweeds will only be economic if the harvesting costs are low. It may be noted that wastes from the alginate industry may be considered a non-cost raw material for energy production.</p>