To see the other types of publications on this topic, follow the link: Algal Protein.
Dissertations / Theses on the topic 'Algal Protein'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Algal Protein.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Turkina, Maria. "Functional proteomics of protein phosphorylation in algal photosynthetic membranes." Doctoral thesis, Linköping : Univ, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10708.
Full text
2
Bosley, Amber L. "Algae Characterization and Processing Techniques." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1321538296.
Full text
3
Casey, Diane M. "DC3, a Calcium-Binding Protein Important for Assembly of the Chlamydomonas Outer Dynein Arm: a Dissertation." eScholarship@UMMS, 2005. http://escholarship.umassmed.edu/gsbs_diss/156.
Full textAbstract:
The outer dynein arm-docking complex (ODA-DC) specifies the outer dynein arm-binding site on the flagellar axoneme. The ODA-DC of Chlamydomonas contains equimolar amounts of three proteins termed DC1, DC2, and DC3 (Takada et al., 2002). DC1 and DC2 are predicted to be coiled-coil proteins, and are encoded by ODA3 and ODA1, respectively (Koutoulis et al., 1997; Takada et al., 2002). Prior to this work, nothing was known about DC3. To fully understand the function(s) of the ODA-DC, a detailed analysis of each of its component parts is necessary. To that end, this dissertation describes the characterization of the smallest subunit, DC3.
In Chapter II, I report the isolation and sequencing of genomic and full-length cDNA clones encoding DC3. The sequence predicts a 21,341 D protein with four EF hands that is a member of the CTER (Calmodulin, Troponin C, Essential and Regulatory myosin light chains) group and is most closely related to a predicted protein from Plasmodium. The DC3 gene, termed ODA14, is intronless. Chlamydomonas mutants that lack DC3 exhibit slow, jerky swimming due to loss of some but not all, outer dynein arms. Some outer doublet microtubules without arms had a "partial" docking complex, indicating that DC1 and DC2 can assemble in the absence of DC3. In contrast, DC3 cannot assemble in the absence of DC1 or DC2. Transformation of a DC3-deletion strain with the wild-type DC3 gene rescued both the motility phenotype and the structural defect, whereas a mutated DC3 gene was incompetent to rescue. The results indicate that DC3 is important for both outer arm and ODA-DC assembly.
As mentioned above, DC3 has four EF-hands: two fit the consensus pattern for calcium binding and one contains two cysteine residues within its binding loop. To determine if the consensus EF-hands are functional, I purified bacterially expressed wild-type DC3 and analyzed its calcium-binding potential in the presence and absence of DTT and Mg2+. As reported in Chapter III, the protein bound one calcium ion with an affinity (Kd) of ~1 x 10-5 M. Calcium binding was observed only in the presence of DTT and thus is redox sensitive. DC3 also bound Mg2+ at physiological concentrations, but with a much lower affinity. Changing the essential glutamate to glutamine in both EF-hands eliminated the calcium-binding activity of the bacterially expressed protein. To investigate the role of the EF hands in vivo, I transformed the modified DC3 gene into a Chlamydomonas insertional mutant lacking DC3. The transformed strain swam normally, assembled a normal number of outer arms, and had a normal photoshock response, indicating that the E to Q mutations did not affect ODA-DC assembly, outer arm assembly, or Ca2+-mediated outer arm activity. Thus, DC3 is a true calcium-binding protein, but the function of this activity remains obscure.
In Chapter IV, I report the initial characterization of a DC3 insertional mutant having a phenotype intermediate between that of the DC3-deletion strain and wild type. Furthermore, I suggest future experiments that may help elucidate the specific role of DC3 in outer arm assembly and ODA-DC function. Lastly, I speculate that the ODA-DC may play a role in flagellar regeneration.
4
Casey, Diane M. "DC3, a Calcium-Binding Protein Important for Assembly of the Chlamydomonas Outer Dynein Arm: a Dissertation." eScholarship@UMMS, 2003. https://escholarship.umassmed.edu/gsbs_diss/156.
Full textAbstract:
The outer dynein arm-docking complex (ODA-DC) specifies the outer dynein arm-binding site on the flagellar axoneme. The ODA-DC of Chlamydomonas contains equimolar amounts of three proteins termed DC1, DC2, and DC3 (Takada et al., 2002). DC1 and DC2 are predicted to be coiled-coil proteins, and are encoded by ODA3 and ODA1, respectively (Koutoulis et al., 1997; Takada et al., 2002). Prior to this work, nothing was known about DC3. To fully understand the function(s) of the ODA-DC, a detailed analysis of each of its component parts is necessary. To that end, this dissertation describes the characterization of the smallest subunit, DC3.
In Chapter II, I report the isolation and sequencing of genomic and full-length cDNA clones encoding DC3. The sequence predicts a 21,341 D protein with four EF hands that is a member of the CTER (Calmodulin, Troponin C, Essential and Regulatory myosin light chains) group and is most closely related to a predicted protein from Plasmodium. The DC3 gene, termed ODA14, is intronless. Chlamydomonas mutants that lack DC3 exhibit slow, jerky swimming due to loss of some but not all, outer dynein arms. Some outer doublet microtubules without arms had a "partial" docking complex, indicating that DC1 and DC2 can assemble in the absence of DC3. In contrast, DC3 cannot assemble in the absence of DC1 or DC2. Transformation of a DC3-deletion strain with the wild-type DC3 gene rescued both the motility phenotype and the structural defect, whereas a mutated DC3 gene was incompetent to rescue. The results indicate that DC3 is important for both outer arm and ODA-DC assembly.
As mentioned above, DC3 has four EF-hands: two fit the consensus pattern for calcium binding and one contains two cysteine residues within its binding loop. To determine if the consensus EF-hands are functional, I purified bacterially expressed wild-type DC3 and analyzed its calcium-binding potential in the presence and absence of DTT and Mg2+. As reported in Chapter III, the protein bound one calcium ion with an affinity (Kd) of ~1 x 10-5 M. Calcium binding was observed only in the presence of DTT and thus is redox sensitive. DC3 also bound Mg2+ at physiological concentrations, but with a much lower affinity. Changing the essential glutamate to glutamine in both EF-hands eliminated the calcium-binding activity of the bacterially expressed protein. To investigate the role of the EF hands in vivo, I transformed the modified DC3 gene into a Chlamydomonas insertional mutant lacking DC3. The transformed strain swam normally, assembled a normal number of outer arms, and had a normal photoshock response, indicating that the E to Q mutations did not affect ODA-DC assembly, outer arm assembly, or Ca2+-mediated outer arm activity. Thus, DC3 is a true calcium-binding protein, but the function of this activity remains obscure.
In Chapter IV, I report the initial characterization of a DC3 insertional mutant having a phenotype intermediate between that of the DC3-deletion strain and wild type. Furthermore, I suggest future experiments that may help elucidate the specific role of DC3 in outer arm assembly and ODA-DC function. Lastly, I speculate that the ODA-DC may play a role in flagellar regeneration.
5
Ronzitti, Giuseppe <1979>. "Le tossine algali alterano proteine dell'adesione cellulare." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/644/1/Tesi_Ronzitti_Giuseppe.pdf.
Full text
6
Ronzitti, Giuseppe <1979>. "Le tossine algali alterano proteine dell'adesione cellulare." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/644/.
Full text
7
Borgen, Kelly. "Evaluation of physicochemical properties of modified algae protein adhesives." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/13634.
Full textAbstract:
Master of ScienceDepartment of Biological and Agricultural Engineering
Donghai Wang
Algae proteins have similar amino acid compositions as conventional plant proteins, and are comparatively richer in the essential amino acids. Algae protein has the potential to be used in the development of a wide variety of products, including foods, animal feeds, bioplastics, and adhesives. The utilization of algae protein for value-added products would increase the economic feasibility of algae biodiesel. This research evaluated the adhesion, rheological, morphological, and thermal properties of adhesives made from algae protein extracted from Cladophora sp. and modified with either sodium hydroxide (pH 9, 10, 11) or sodium dodecyl sulfate (SDS, 0.5, 1, and 3%). Both alkali-modified and SDS-modified algae protein adhesives displayed improved dry shear strength compared to unmodified algae protein. However, only 3% SDS-modified algae protein significantly improved the water resistance as shown in wet and soak shear strength tests. Thermal analysis using differential scanning calorimetry showed that SDS modification caused complete denaturation of the algae protein. SDS modification also increased the viscosity of the adhesive and created rougher particle surface texture. These data suggest that SDS modification can effectively increase shear strength and water resistance of algae protein adhesives caused by protein denaturation and protein structure change.
8
Azevedo, Brian. "Algae as an economical protein source for dairy cattle nutrition." Click here to view, 2009. http://digitalcommons.calpoly.edu/dscisp/23/.
Full textAbstract:
Thesis (B.S.)--California Polytechnic State University, 2009.Project advisor: Edwin H. Jaster. Title from PDF title page; viewed on Jan. 28, 2010. Includes bibliographical references. Also available on microfiche.
9
Djabayan-Djibeyan, Pablo. "A comparison of lectins in green Venezuelan marine algae." Thesis, University of Portsmouth, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343338.
Full text
10
Lupatini, Anne Luize. "Extração de proteínas e carboidratos da biomassa de Spirulina platensis e caracterização da fração proteica." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/2180.
Full textAbstract:
CAPES; CNPQA Spirulina platensis é reconhecida como uma fonte não convencional de proteínas, em função da sua constituição favorável deste nutriente (46 a 63%), possuindo concentração superior a das carnes e da soja. Além disso, apresenta potencial como matéria-prima para a produção de bioetanol, podendo acumular entre 8,0 e 14,0% de carboidratos. A fim de abranger o conceito de Biorrefinarias Integradas, o objetivo deste trabalho consistiu em avaliar a extração conjunta de proteínas e carboidratos da biomassa de Spirulina platensis utilizando tratamento ultrassônico e agitação em meio alcalino, e a posterior produção e caracterização do concentrado proteico. Na primeira etapa do trabalho, aplicou-se uma estratégia sequencial de planejamento experimental (Planejamento Fatorial Fracionário (PFF) seguido de Delineamentos Compostos Centrais Rotacionais (DCCR)) para seleção e maximização das variáveis com influência significativa sobre o processo de extração. Com as condições de extração otimizadas, foi possível atingir recuperação final de 75,85% e de 41,54% de proteínas e carboidratos, respectivamente. Na segunda etapa do trabalho foi realizada a precipitação de proteínas, para a separação da fase líquida contendo os carboidratos e obtenção do concentrado proteico, o qual foi caracterizado quimicamente e de acordo com sua funcionalidade tecnológica. O concentrado proteico apresentou coloração verde azulada com 75,97% de proteínas (b.s.), concentrações apreciáveis de aminoácidos, sendo o que o triptofano apresentou o maior escore químico (1,71) e o aminoácido limitante foi a histidina; na análise da estrutura secundária das proteínas, as conformações mais abundantes foram β-folha e α-hélice. Na etapa de avaliação da funcionalidade tecnológica observou-se que o pH apresentou influência nas propriedades de capacidade de absorção de água, capacidade de formação e estabilidade de espuma e emulsão, e capacidade de formação de gel, o que pode ser justificado pela solubilidade desta proteína, que é mínima em pH 3,0 e máxima em 9,0. A concentração de concentrado proteico também interferiu no desempenho destas propriedades; melhores resultados foram obtidos em maiores níveis de concentração, exceto para a capacidade de absorção de água e de óleo. Desta forma foi possível determinar que as proteínas de Spirulina platensis podem contribuir na formulação de alimentos, possuindo características eficazes de formação de emulsões, espumas ou géis, bem como pode ser utilizada como fonte suplementar de proteínas.
Spirulina platensis is considered an unconventional source of protein, because its avorably constitution on this component (46 to 63%), which is higher than the meat and soy. Furthermore, it has potential as a feedstock for bioethanol production and can accumulate between 8.0 to 14.0% of carbohydrate. In order to cover the concept of Integrated Biorefineries, the aim of this study was to evaluate the combined extraction of proteins and carbohydrates from Spirulina platensis biomass using sonication and agitation, under alkaline conditions, and the subsequent production and characterization of protein concentrate. The first stage of this work consisted of applying a sequential strategy of experimental design (Fractional Factorial Design FFD) and Central Composite Rotatable Design (CCRD)) by selecting and maximizing variables with significant influence on the protein and carbohydrates extraction. With the extraction conditions established, a final yield of 75.85% and 41.54% from protein and carbohydrate, respectively, was reached. In the second step, the protein concentrate obtained by precipitation was submitted to chemical and echnological functionality analyzes. The protein concentrate showed blue-green color with 75.97% of proteins (dry weight), appreciable concentrations of amino acids, where tryptophan had the highest chemical score (1.71) and the limiting amino acid was histidine; the secondary structure of proteins showed that the most abundant conformations present were β-sheet and α-helice. At the step of echnological functionality evaluation it was observed that the pH influenced on the properties of water absorption capacity, foaming and emulsion capacity and stability, and gelation capacity; it can be justified by the solubility of this protein which is minimal at pH 3.0 and maximum at 9.0. The level of addition of protein concentrate also interfered on the performance of these properties; better results have been obtained at higher concentrations levels, except for water and oil absorption capacity. Thus, it was confirmed that the Spirulina platensis proteins may contribute in different ormulations of foods, having effective characteristics to form emulsions, foams or gels, and can be used as a supplemental source of protein.
11
Andronis, Christos. "Site-directed mutagenesis of the D2 protein in the green alga 'Chlamydomonas reihardtii'." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243328.
Full text
12
Ibuot, Aniefon. "Evaluation of the use of algae for bioremediation of toxic metal pollutants." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/evaluation-of-the-use-of-algae-for-bioremediation-of-toxic-metal-pollutants(db60de2c-ff75-4ece-b3a0-b67655bcadbb).html.
Full textAbstract:
Metal pollution has been a great challenge in most industrialized countries as a result of waste generated from industrial activities being introduced into the environment. Unicellular green algae have been considered a potential biological tool for bioremediation of metal pollutants due to its metal sequestration properties. However, methods for further improving unicellular green algae metal sequestration by manipulating metal uptake and tolerance in unicellular green algae have not been studied in detail. In this study, a family metal transport protein named MTP1 - MTP4 from C. reinhardtii were screened by yeast heterologous expression for metal transport activity. MTP1 was able to strongly rescue the Zn and Co sensitivity of the zrc1cot1 strain, MTP3 could weakly mediate Zn and Co growth, but MTP2 and MTP4 appeared to have no Zn or Co tolerance activity. MTP2, MTP3 and MTP4 but not MTP1 could strongly rescue the Mn sensitivity of the pmr1 strain. When MTP4 was over-expressed in C. reinhardtii the strain showed a significant increase in Cd tolerance compared to the wild type, but no significant difference in Mn tolerance and uptake. AtHMA4 a Zn2+ and Cd2+ transporter from the plant Arabidopsis thaliana, which is a member of the Heavy Metal ATPase family, was also expressed in C. reinhardtii. HMA4 full length and C-terminal tail expression strains were screened for Zn and Cd tolerance and uptake. Both sets of strains showed a significant increase in Cd and Zn tolerance and uptake compared to the wild type. Metal tolerance and uptake was compared between the genetically engineered C. reinhardtii strains and unicellular green algal strains that are naturally adapted to metal tolerance which were P. hussi, P. kessleri, and C. luteoviridis. Results showed significant increase in Zn and Cd tolerance and uptake in the natural strains compared to the engineered strains. Therefore in addition to genetically engineered strains, naturally adapted strains could also be used as tools for effective metal bioremediation and pollutant treatment.
13
Arakaki, Yoko, Takayuki Fujiwara, Hiroko Kawai-Toyooka, Kaoru Kawafune, Jonathan Featherston, Pierre M. Durand, Shin-ya Miyagishima, and Hisayoshi Nozaki. "Evolution of cytokinesis-related protein localization during the emergence of multicellularity in volvocine green algae." BIOMED CENTRAL LTD, 2017. http://hdl.handle.net/10150/626422.
Full textAbstract:
Background: The volvocine lineage, containing unicellular Chlamydomonas reinhardtii and differentiated multicellular Volvox carteri, is a powerful model for comparative studies aiming at understanding emergence of multicellularity. Tetrabaena socialis is the simplest multicellular volvocine alga and belongs to the family Tetrabaenaceae that is sister to more complex multicellular volvocine families, Goniaceae and Volvocaceae. Thus, T. socialis is a key species to elucidate the initial steps in the evolution of multicellularity. In the asexual life cycle of C. reinhardtii and multicellular volvocine species, reproductive cells form daughter cells/colonies by multiple fission. In embryogenesis of the multicellular species, daughter protoplasts are connected to one another by cytoplasmic bridges formed by incomplete cytokinesis during multiple fission. These bridges are important for arranging the daughter protoplasts in appropriate positions such that species-specific integrated multicellular individuals are shaped. Detailed comparative studies of cytokinesis between unicellular and simple multicellular volvocine species will help to elucidate the emergence of multicellularity from the unicellular ancestor. However, the cytokinesis-related genes between closely related unicellular and multicellular species have not been subjected to a comparative analysis. Results: Here we focused on dynamin-related protein 1 (DRP1), which is known for its role in cytokinesis in land plants. Immunofluorescence microscopy using an antibody against T. socialis DRP1 revealed that volvocine DRP1 was localized to division planes during cytokinesis in unicellular C. reinhardtii and two simple multicellular volvocine species T. socialis and Gonium pectorale. DRP1 signals were mainly observed in the newly formed division planes of unicellular C. reinhardtii during multiple fission, whereas in multicellular T. socialis and G. pectorale, DRP1 signals were observed in all division planes during embryogenesis. Conclusions: These results indicate that the molecular mechanisms of cytokinesis may be different in unicellular and multicellular volvocine algae. The localization of DRP1 during multiple fission might have been modified in the common ancestor of multicellular volvocine algae. This modification may have been essential for the re-orientation of cells and shaping colonies during the emergence of multicellularity in this lineage.
14
Nicholson, Theodore Roosevelt III. "Interfacial Design and Protein Engineering as Tools of Biomedical Nanotechnology in the Optimization of Protein Detecting Field Effect Transistors." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1290575487.
Full text
15
Wang, Lianyong. "A calcium-binding protein CAS regulates the CO2-concentrating mechanism in the green alga Chlamydomonas reinhardtii." Kyoto University, 2017. http://hdl.handle.net/2433/218025.
Full text
16
Wen, Xuejin. "Design, Fabrication, and Characterization of Field-Effect and Impedance Based Biosensors." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1308312352.
Full text
17
Gupta, Samit Kumar. "Development of a planar immunoFET which detects protein analyte in high salt environments." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1290575121.
Full text
18
Correa, Galvis Viviana Andrea [Verfasser]. "The role of the PsbS protein in the regulation of energy dissipation in vascular plants and green algae / Viviana Andrea Correa Galvis." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2016. http://d-nb.info/1084169843/34.
Full text
19
Cheng, Qi. "Studies in the expression and function of Klebsiella pneumoniae nitrogenase iron protein in the chloroplast of the eukaryotic unicellular green algae - Chlamydomonas reinhardtii." Thesis, University of East Anglia, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302041.
Full text
20
Nostadt, Robin [Verfasser], and Alga [Akademischer Betreuer] Zuccaro. "Localization and biochemical characterization of the small secreted protein Dld1 from the root endophytic fungus Piriformospora indica / Robin Nostadt ; Betreuer: Alga Zuccaro." Marburg : Philipps-Universität Marburg, 2019. http://d-nb.info/1193177553/34.
Full text
21
Sun, Hongwei. "The effect of seaweed concentrate on turfgrass growth, nematode tolerance and protein synthesis under moisture stress conditions." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-163430/.
Full text
22
Nascimento, Fernando Edson Pessoa do. "Identification of proteins from the marine red macroalga Hypnea musciformis by proteomic analysis." reponame:Repositório Institucional da UFC, 2014. http://www.repositorio.ufc.br/handle/riufc/18311.
Full textAbstract:
NASCIMENTO, Fernando Edson Pessoa do. Identificação de proteínas da macroalga marinha vermelha Hypnea musciformis por análise proteômica. 2014. 62 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2014Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-14T13:19:27Z No. of bitstreams: 1 2014_dis_fepnascimento.pdf: 1476110 bytes, checksum: a37b0bfbc43de7460d0259fd1a190bb2 (MD5)
Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-14T13:19:45Z (GMT) No. of bitstreams: 1 2014_dis_fepnascimento.pdf: 1476110 bytes, checksum: a37b0bfbc43de7460d0259fd1a190bb2 (MD5)
Made available in DSpace on 2016-07-14T13:19:45Z (GMT). No. of bitstreams: 1 2014_dis_fepnascimento.pdf: 1476110 bytes, checksum: a37b0bfbc43de7460d0259fd1a190bb2 (MD5) Previous issue date: 2014
Atualmente vivemos em uma acirrada competição na pesquisa de desenvolvimento de novos produtos biotecnológicos, o ambiente marinho pode ser visto como uma fonte de materiais biotecnológicos funcionais. Recentemente, estudos demostram que dentro do ambiente marinho as algas se destacam como organismos com grande potencial biotecnológico por possuirem em sua composição várias moléculas bioativas que apresentam diversas e intensas atividades biológicas. Dentre todos os grupos algais, neste trabalho enfatizamos o das algas vermelhas, a qual a espécie de estudo é a alga marinha vermelha Hypnea musciformis (Wulfen). J. V. Lamouroux pertence à ordem Gigartinales e a família Hypneaceae, abundante no litoral do Ceará. Trabalhos biotecnológicos e científicos são realizados com esta espécie, neste sentido o objetivo principal deste trabalho e identificar e caracterizar proteínas existente neste organismo através de uma abordagem proteômica, que é uma área recente na ciência, que permite bioprospectar um conjunto de proteínas presentes num organismo através do uso de ferramentas analíticas, pois, em condições fisiológicas específicas, o funcionamento do sistema biológico pode ser refletido por análise do proteoma do mesmo, e assim a sua expressão gênica funcional. Considerando a carência de estudos sobre proteômica em algas marinhas e em especial da carragenófita Hypnea musciformis, o presente trabalho tem como objetivo principal desenvolver metodologias de separação de proteínas de extrato protéico de Hypnea musciformis e identificar as proteínas expressas pelo organismo. Neste trabalho conseguimos estabelecer uma metodologia de separação de proteínas deste organismo a partir de um extrato fracionado com sulfato de amônio e através de espectrometria de massas, identificar algumas proteínas da alga marinha. Desta forma, sendo de fundamental importância para o enriquecimento na literatura de proteomica de macroalgas marinhas. Os resultados deste trabalho que estão de acordo com o nosso objetivo foi a identificação de 3 proteínas por técnica de espectrometria de massas utilizando ionização do tipo eletrospray da fração protéica 20-40% e a identificação de algumas proteínas através do Mascot
We currently live in a fierce competition in the research development of new biotechnology products, the marine environment can be seen as a source of functional biotechnological materials. Recent studies show that within the marine environment algae stand out as organisms with great biotechnological potential by having in its composition various bioactive molecules that have diverse and intense biological activities, among all algal groups in this study emphasize the of red algae, which the kind of study is red seaweed Hypnea musciformis (Wulfen). JV Lamouroux belongs to the order Gigartinales and Hypneaceae family, abundant on the coast of Ceará. Biotechnological and scientific works are carried out with this species, in this sense, the main objective of this work is to identify and characterize proteins existing in this organism through a proteomics approach, is a new area in science that allows bioprospect a set of proteins in an organism by using analytical tools because under specific physiological conditions the biological functioning of the system can be reflected by the proteome analysis of the same, and thus the functional gene expression. Considering the lack of studies on proteomics in seaweed and in particular the carragenófita Hypnea musciformis, this paper aims to develop methods for separating proteins from protein extract of Hypnea musciformis and identify the proteins expressed by the organism. In this work we have established a methodology for separating proteins of this organism from a fractionated extract with ammonium sulfate and by mass spectrometry to identify proteins of some kelp, thus being of fundamental importance for the enrichment of macroalgae in the proteomics literature marine. The results of this work are consistent with our objective was the identification of three proteins by mass spectrometry using electrospray ionization type protein fraction of 20-40% and the identification of some proteins by Mascot
23
Redekop, Petra [Verfasser], Peter [Gutachter] Jahns, and Andreas P. M. [Gutachter] Weber. "The role of the PsbS protein in high light acclimation of the green alga Chlamydomonas reinhardtii / Petra Redekop ; Gutachter: Peter Jahns, Andreas P. M. Weber." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2019. http://d-nb.info/118267223X/34.
Full text
24
DUCHER, TARDY MIREILLE. "Role de la lumiere sur la morphogenese et le metabolisme du thalle de draparnaldia mutabilis (roth-cederg)." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF2E386.
Full textAbstract:
Influence de differentes intensites d'eclairement sur la ramification du thalle, l'organisation et la differenciation du chloroplaste. Sur la croissance avec action du phytochisme, sur la photosynthese, le metabolisme du glycolate et glucides solubles et insolubles
25
DeMicco, Erik David. "Feasibility of Using Biofuel By-Products as a Sustainable Nutritional Resource for Aquaculture Production of Litopenaeus vannamei." NSUWorks, 2015. http://nsuworks.nova.edu/occ_stuetd/387.
Full textAbstract:
Many different algal species can provide an acceptable protein ingredient, with good digestibility, for shrimp feeds. Compared to fish meal, similar protein, carbohydrate, and lipid levels can be found in select algal species. Traditional shrimp diets in aquaculture rely on fish meal and fish oil from pelagic fish fisheries. A reduction or elimination of these ingredients would reduce the dependency of shrimp aquaculture on offshore fisheries and increase economic competiveness. Biofuel production produces algal by-products of potential use to aquaculturists that might reduce or eliminate the need for fisheries products in shrimp feed. Established uses for by-products from biofuel production include fertilizer for crops, fodder for swine and poultry, and production of methane and alcohol fuels. However, using biofuel production by-products as a protein and carbohydrate source for the Pacific white shrimp, Litopenaeus vannamei, has not been investigated. Therefore, a series of feeding experiments were conducted to evaluate if the algae used to produce biofuel could be a suitable main protein source in formulated diets for L. vannamei.
The feasibility of substituting biofuel algae by-product for fish meal in the juvenile L. vannamei (0.0306 ± 0.0011 g) diet was evaluated, and an adequate substitution ratio was determined. Eighteen experimental diets were evaluated using 60, 80, and 100% fish meal substitution levels. Chaetoceros calcitrans, Nannochloropsis salina, and Pavlova sp. were chosen as the algae sources as they have potentially high use in biodiesel production due to their high lipid content and each has been included in established larval shrimp aquaculture operations. Each diet varied the level of fish meal substitution (60, 80, or 100%) and either contained dried algal biomass or, alternatively, dried algal biomass with reduced lipid content to simulate algal biomass post-biodiesel production. The diets were compared, relative to their effect on weight gain in juvenile L. vannamei, to each other and to a commercially available diet (CONTROL) and a diet formulated using the ingredients used in all of the experimental diet formulations but without algal biomass (BASAL).
The shrimp were held individually in 355-ml Styrofoam cups filled with 200-ml seawater with a salinity of 32 parts per thousand (ppt) salinity under a 12:12 light:dark photoperiod. Water exchange was 90% per day for six days and 100% on the seventh day when weights were taken. Each of the twenty diets was presented daily to seven replicate cups, each cup containing a single shrimp, for six weeks. Food was presented once per day to satiation, which was determined by the shrimp refusing additional feed. Each animal was weighed weekly. After six weeks, the shrimp were harvested and final weights were taken.
The analysis of differences between strains, levels, and lipids indicated there was a significant difference between all of the algal-based diets and the control. Overall, significantly better growth rates were observed in the diets with less fish protein replacement. The 60% fish meal replaced diets outperformed the diets that had 80 or 100% fish meal replacement. There were no significant differences in nutritional value among the algal species. Survival rates, from an aquaculture perspective, were acceptable for all treatments (>71%).
Results from these studies demonstrated that formulated diets using algal biomass from biodiesel production can be the primary protein source for L. vannamei postlarvae.
26
Hanschen, Erik R., Tara N. Marriage, Patrick J. Ferris, Takashi Hamaji, Atsushi Toyoda, Asao Fujiyama, Rafik Neme, et al. "The Gonium pectorale genome demonstrates co-option of cell cycle regulation during the evolution of multicellularity." NATURE PUBLISHING GROUP, 2016. http://hdl.handle.net/10150/614763.
Full textAbstract:
The transition to multicellularity has occurred numerous times in all domains of life, yet its initial steps are poorly understood. The volvocine green algae are a tractable system for understanding the genetic basis of multicellularity including the initial formation of cooperative cell groups. Here we report the genome sequence of the undifferentiated colonial alga, Gonium pectorale, where group formation evolved by co-option of the retinoblastoma cell cycle regulatory pathway. Significantly, expression of the Gonium retinoblastoma cell cycle regulator in unicellular Chlamydomonas causes it to become colonial. The presence of these changes in undifferentiated Gonium indicates extensive group-level adaptation during the initial step in the evolution of multicellularity. These results emphasize an early and formative step in the evolution of multicellularity, the evolution of cell cycle regulation, one that may shed light on the evolutionary history of other multicellular innovations and evolutionary transitions.
27
Houlné, Guy. "Structure et expression des genes codant pour les apoproteines des antennes collectrices de photons ps2 et ps1 chez euglena gracilis." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13169.
Full text
28
Melo, Thiago Anchieta de. "Efeito do extrato da alga marinha Ascophyllum nodosum e do fosfito de potássio na morfofisiologia do fungo Colletotrichum gloeosporioides, na indução de resistência em mangas \'Tommy Atkins\' contra a antracnose e em características físicas e químicas desses frutos." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11135/tde-20032018-105839/.
Full textAbstract:
A mangicultura é uma das atividades mais importantes para a fruticultura brasileira. Dentre as variedades produzidas, o cultivar \'Tommy Atkins\', sem dúvida, é o mais expressivo. Após a colheita, a qualidade fisiológica das mangas, geralmente, é mantida pela integração de técnicas de controle físico e aplicação de moléculas com atividade biológica contra microrganismos, a exemplo dos fungicidas aplicados no controle do fungo Colletotrichum gloeosporioides, agente causal da antracnose, principal doença na fase de pós-colheita de mangas. Entretanto, atualmente há forte pressão da população para a utilização de moléculas que deixem nenhum ou o mínimo possível de resíduos em alimentos, especialmente os consumidos in natura. Vários produtos são vendidos no Brasil como biofertilizantes, mas, estes apresentam também, a capacidade de mitigar estresses bióticos e abióticos, inerentes da vida pós-colheita de frutas. Nesse contexto, pode-se citar o extrato da alga marinha Ascophyllum nodosum (Acadian®) e o fosfito de potássio (Phytogard®), utilizados em vários passos do processo de produção agrícola, mostrando respostas diversas sobre os vegetais tratados. Ambos os produtos apresentam baixa toxicidade ao homem e ao ambiente e não são fitotóxicos. Assim, com a ideia de gerar informação mais acertada acerca dos processos envolvidos a partir da utilização desses produtos, na cadeia produtiva da manga, este trabalho foi construído sobre três vertentes principais. A primeira parte, objetivou verificar o efeito in vitro do extrato da alga marinha A. nodosum e do fosfito de potássio sobre a morfofisiologia do fungo C. gloeosporioides isolado de mangas, variedade \'Tommy Atkins\'. Na segunda parte, o objetivo do trabalho foi avaliar o efeito do extrato da alga marinha A. nodosum e do fosfito de potássio, ambos aplicados em diferentes concentrações, sobre o parasitismo do fungo 1 em mangas \'Tommy Atkins\', na perspectiva da indução de resistência, na fase de pós-colheita desses frutos. Finalmente, na terceira parte do trabalho, objetivou-se verificar o efeito do extrato da alga marinha A. nodosum e do fosfito de potássio, ambos aplicados em diferentes concentrações, sobre características físicas e químicas de mangas \'Tommy Atkins\', na fase de pós-colheita. Como resultados da primeira parte do trabalho, observou-se que o extrato de algas induz o crescimento e a esporulação do fungo, inibindo, contudo, a germinação e a fixação de conídios produzidos pelo patógeno. O fosfito de potássio interfere no crescimento e esporulação do microrganismo e inibe a germinação e adesão de conídios produzidos por C. gloeosporioides. Os dois produtos alteram a permeabilidade seletiva da membrana plasmática da hifa e incrementam a atividade das enzimas β-1,3-glucanase e quitinase na estrutura. Entretanto, somente o extrato de algas interferiu no conteúdo total de proteínas da hifa, aumentando esse parâmetro. Os dois produtos diminuíram a atividade celulolítica de C. gloeosporioides. Na segunda parte, os resultados demonstraram que, tanto para o extrato de algas quanto para o fosfito de potássio, houve diminuição do tamanho da lesão, da velocidade de crescimento da lesão e da AACPD. Além disso, foram observados incrementos em todos os parâmetros bioquímicos analisados, o que indicou que os produtos têm efeito indutor de resistência em mangas. Finalmente, como resultados para a terceira parte do trabalho, foi evidenciado que tanto o extrato de algas quanto o sal de potássio, em todas as concentrações utilizadas, ajudaram na redução da perda de massa dos frutos, retardaram a diminuição do ângulo de cor da polpa (ângulo Hue) e a firmeza desta. Além disso, os produtos testados desaceleraram a perda de acidez da polpa e mantiveram elevados os valores de ácidos orgânicos, a exemplo do ácido cítrico; mantiveram abaixo do tratamento controle o conteúdo de sólidos solúveis (°Brix), mas não interferiram no total de carboidratos encontrados nas cascas dos frutos. Conclusivamente, o extrato de A. nodosum e o fosfito de potássio, retardam o amadurecimento e senescência de mangas na fase de pós-colheita, reduzem a severidade da antracnose nos frutos pela indução de resistência e ainda, apresentam efeitos diretos sobre o fungo C. gloeosporioides. Dessa maneira, os produtos podem ser utilizados como mantenedores da qualidade fisiológica de mangas \'Tommy Atkins\', pois minimizam os estresses de ordem biótica e abiótica relativos à vida pós-colheita dessas frutas.Mango farming is one of the most important activities for Brazilian fruit growing. Among the varieties produced, the cultivar \'Tommy Atkins\' is undoubtedly the most expressive. After harvesting, the physiological quality of mangoes is generally maintained by the integration of physical control techniques and the application of molecules with biological activity against microorganisms, such as the fungicides applied in the control of the fungus Colletotrichum gloeosporioides, the causal agent of anthracnose, the main disease in the postharvest phase of mangoes. However, there is currently strong population pressure for the use of molecules that leave none or the least possible residues in food, especially those consumed in natura. Several products are sold in Brazil as biofertilizers, but also present the ability to mitigate biotic and abiotic stresses inherent of the postharvest fruit life. Ascophyllum nodosum seaweed extract (Acadian®) and potassium phosphite (Phytogard®), both used in several steps of the agricultural production process, can be mentioned in this context, showing different responses on treated plants. Both products have low toxicity to man and the environment and are not phytotoxic. Thus, in order to generate precise information about the processes involved in the use of these products, in the production chain of mango, this work was built on three main strands. The first part aimed to verify the in vitro effect of the A. nodosum seaweed extract and the potassium phosphite on the morphophysiology of the fungus C. gloeosporioides isolated from mangoes \'Tommy Atkins\'. In the second part, the objective of this work was to evaluate the effect of A. nodosum seaweed extract and the potassium phosphite, both applied in different concentrations, on the parasitism of the fungus C. gloeosporioides in mangoes \'Tommy Atkins\', from the perspective of induction of resistance in the postharvest phase of these fruits. Finally, in the third part of the work, the objective was to verify the effect of A. nodosum seaweed extract and of the potassium phosphite, both applied in different concentrations, on physical and chemical characteristics of \'Tommy Atkins\' mangoes in the postharvest stage. As results of the first part of this work, it was observed that the algae extract induces the growth and sporulation of the fungus; however, it inhibits the germination and adhesion of conidia produced by the pathogen. Potassium phosphite interferes with the growth and sporulation of the microorganism and inhibits the germination and adhesion of conidia produced by C. gloeosporioides. The two products alter the selective permeability of hypha plasma membrane and increase the activity of the enzymes β-1,3-glucanase and chitinase in the structure. However, only the algae extract interfered in the total protein content of the hypha, increasing this parameter. The two products decreased the cellulolytic activity of C. gloeosporioides. In the second part, the results demonstrated that, for both algae extract and potassium phosphite, there was a decrease in lesion diameter, lesion growth rate and AUDPC. In addition, increments were observed in all biochemical parameters analyzed, which indicated that the products have resistance-inducing effect on mangoes. Finally, as results for the third part of the work, it was evidenced that both the algae extract and the potassium salt, in all the concentrations used, helped to reduce the loss of mass of the fruits, delayed the decrease of pulp color angle (Hue angle) and the firmness of this. In addition, the products tested decelerated the loss of acidity of the pulp and maintained high values of organic acids, as citric acid; controlled soluble solids content in relation to the control (°Brix), but did not interfere in the total carbohydrate found in the fruit peels. Conclusively, the A. nodosum extract and potassium phosphite, delay the maturation and senescence of mangoes in the post-harvest phase, reduce the severity of the anthracnose in the fruits by the induction of resistance and also have direct effects on the fungus C. gloeosporioides. In this way, the products can be used to maintain the physiological quality of \'Tommy Atkins\' mangoes, since they minimize the biotic and abiotic stresses related to the postharvest life of these fruits.
29
Keller, Mario. "Etude des genes de trna chloroplastiques et du gene de la proteine thylakoidale de 32 kd du photosysteme ii chez euglena gracilis : localisation et sequence nucleotidique." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13007.
Full textAbstract:
Le fractionnement des trna chloroplastiques d'euglena gracilis d'une part par electrophorese bidimensionnelle sur gel de polyacrylamide et d'autre part, par chromatographie sur sepharose 4b a permis d'identifier 24 isoaccepteurs specifiques de 18 aminoacides. Plusieurs de ces trna ont ete purifies et utilises pour localiser leur gene sur le dna chloroplastique. Les genes de trna sont dissemines tout au long de la molecule circulaire du genome plastidial; deux d'entre eux, les genes de trna**(ala) et trna**(ile) sont localises dans la region intercistronique separant les genes des rrna 23s et 16s. Les resultats obtenus lors de ce travail, montrent que la structure et l'organisation des genes de trna et des proteines chloroplastiques d'euglene different de celles observees pour les genes homologues de vegetaux superieurs. Ces divergences suggerent que les chloroplastes d'euglene proviendraient d'un evenement different de celui ayant ete a l'origine des chloroplastes des vegetaux superieurs
30
Souza, Imyra Maíra Martins de. "A influência do fósforo na toxicidade de cobre e composição bioquímica de Chlorella vulgaris." Universidade Federal de São Carlos, 2011. https://repositorio.ufscar.br/handle/ufscar/2048.
Full textAbstract:
Made available in DSpace on 2016-06-02T19:31:59Z (GMT). No. of bitstreams: 1
3988.pdf: 740550 bytes, checksum: c474fd35724dbe7bdd263dbd50611faf (MD5)
Previous issue date: 2011-09-02Financiadora de Estudos e Projetos
Metal toxicity to microalgae is dependent on environmental conditions, evolutionary history of the microalgae, and previous exposure of the organism to the specific metal. Also, it is importantly influenced by the physiological condition of the algae in the moment of metal exposure. In this research we investigated several combinations of phosphorus (P) and copper (Cu) concentrations on the biochemical composition and Cu toxicity to Chlorella vulgaris. Due to its known toxicity, copper was considered in its free Cu2+ ions specie. Because microalgae physiology reflects the environmental conditions, but it also stores some of the inorganic nutrients, previous to Cu spike in the cultures, the algae were acclimated to each treatment s specific P concentration to be tested in combination with Cu. We considered cells were acclimated to a specific P concentration after its growth rate had been stabilized for at least four generations, always transferring the cells while in the beginning of the exponential growth phase. Biomass and physiological parameters analyzed were cell number (cell.mL-1), chlorophyll-a concentration, dry weight, lipid classes (Iatroscan TLC/FID), and total cellular proteins and carbohydrates at several combinations of P/Cu. The P concentrations tested were 5.0x10-5, 2.5x10-5, 5.0x10-6 and 1.0x10-6 mol.L-1 and the free Cu2+ ions concentrations ranged within 1x10-10 and 5x10-8 mol.L-1, and were determined through ion selective electrode (ISE). Our results showed that Cu toxicity to C. vulgaris increased at low P. Carbohydrate, protein and lipid productions were in general triggered at low P and high Cu, with some exceptions. TAG was the lipid class most affected by stressing situations. AMPL and PL were the lipid classes with the higher percent composition amog the classes; HC, WE and ST were present in minor amounts even under stressing situations.
As microalgas apresentam uma estreita relação com o meio circundante, sendo a parede e membrana celulares a via de entrada dos compostos dissolvidos. Mas, o modo como as algas interagem com os metais no ambiente, depende grandemente da especiação química do elemento. Portanto, a toxicidade de metais para microalgas relaciona-se, não somente com sua história evolutiva e condição fisiológica, mas também com a forma em que o metal é encontrado no ambiente. Nesta pesquisa, investigamos o efeito de diversas combinações de concentrações de fosfato (P) e cobre (Cu) na toxicidade do micronutriente e na composição bioquímica da microalga de água doce Chlorella vulgaris. O cobre foi analisado na forma iônica livre pois esta é uma das espécies de maior toxicidade para as algas. Antes da adição de cobre, a microalga foi aclimatada para a concentração de fosfato do respectivo tratamento experimental (P:Cu). As células foram consideradas aclimatadas para uma concentração específica de P após sua taxa de crescimento ter sido estabilizada por quatro gerações, sempre transferindo as células em fase inicial de crescimento exponencial. Para cada tratamento efetuado, os parâmetros de biomassa e fisiológicos analisados foram número de células por mL, concentração de clorofila-a, biomassa seca, classes lipídicas, através do equipamento (Iatroscan TLC/FID), proteínas e carboidratos celulares totais. As concentrações de P testadas foram 5,0x10-5, 2,5x10-5, 5,0x10-6 e 1,0x10-6 mol.L-1 e a amplitude de concentração de ions Cu2+ livres ficou entre 1x10-10 and 5x10-8 mol.L-1. Cobre livre foi determinados através de eletrodo seletivo ao íon (ISE) cobre. Nossos resultados mostraram que a toxicidade de Cu para C. vulgaris foi afetada pela concentração de fosfato no meio de cultura. Em baixas concentrações de fósforo, houve a maior toxicidade do Cu, aumento na produção de carboidratos e de lipídios. A análise das classes lipídicas revelaram que os hidrocarbonetos alifáticos (HC), ésteres de cera (WE) e esterol (ST) tiveram sua síntese ativada em concentrações tóxicas de Cu e de baixo fósforo. Similarmente, a síntese proteica aumentou sob essas condições, com a maior quantidade de síntese proteica obtida na menor concentração fósforo testada.
31
Metivier, Christine. "La motilité chez le dinoflagellé évolué Noctiluca Scintillans Mccartney : organisation structurale, régulation ionique, caractérisation biochimique et immunologique des protéines corticales." Paris 6, 1986. http://www.theses.fr/1986PA066243.
Full textAbstract:
La motilité du tentacule du dinoflagellé Noctiluca Scintillans et les mouvements du cytostome dépendent d'un épiplasme fibreux périphérique, d'un réseau microtubulaire longitudinal sous-jacent à l'épiplasme et de myonèmes transversaux striés contractiles. L'étude de l'organisation de ce cytosquelette et de la contractilité des myonèmes du tentacule et du cytostome ont été réalisées en microscopie électronique. Le rôle des microtubules des myonèmes, du magnésium, de l'ATP extracellulaires et plus particulièrement celui du calcium au cours de la motilité ont été précisées ainsi que la recherche de la présence d'actine intracellulaire et la caractérisation biochimique et immunologique des 3 protéines majoritaires du cytosquelette (45, 80 et 140 KD).
32
D'Souza, Frances M. L. "The nutritional value of microalgae to penaeid prawn larvae." Thesis, Queensland University of Technology, 1997. https://eprints.qut.edu.au/36935/1/36935_Digitised%20Thesis.pdf.
Full textAbstract:
This is the first study to investigate the nutritional requirements of the penaeid prawn protozoeal phase (the first feeding stage of the prawn life cycle) using micro algae to provide different nutritional conditions.
The work was a simultaneous examination of the biochemical
composition of the larvae and their microalgal diets. In addition, the influence of naupliar composition on later larval stages was studied. The biochemical parameters measured were total protein, lipid and carbohydrate (i.e. gross biochemical composition) and total lipid was further resolved into individual fatty acids.
The nutritional requirements of penaeid prawn larvae were assessed by measuring the survival, development (metamorphosis) and growth (in terms of dry weight) of larvae in response to various algal diets. In
this way differences in survival, development and growth could be related to biochemical differences in the algal diets and associated larval body composition.
The changes in biochemical composition of *Penaeus japonicus* and *P. monodon* larvae during metamorphosis from nauplii to protozoea 1 (PZl) and the time course of these changes during starvation and feeding for the ~42 h period that the PZl stage lasts, were examined. The larvae utilised lipid as a major energy source during metamorphosis. The fatty acid fraction of the lipid in nauplii was high
(60 to 80%) compared with protozoeae (30 to 60%) and provided a large proportion of the energy required for metamorphosis. Of the total fatty acids, the monounsaturated (MUFAs) and saturated fatty
acids contributed most of this energy. During starvation the MUFAs and polyunsaturated fatty acids (PUPAs) were metabolised while the highly unsaturated fatty acids (HUFAs) were conserved, presumably because of their role as structural components in cell membranes. The
PUFA linoleic acid (18:2n-6) appeared to have a role as a component of cell membranes when in short supply, but it accumulated as an energy reserve when in excess in the diet. Linolenic acid (18:3n-3) was actively metabolised to other membrane fatty acids or used for energy.
The effect of altering the biochemical composition of the microalga
*Tetraselmis suecica* on *P. semisulcatus* larvae was studied by reducing the nitrate concentration from -1760 μ*M* to 176 μ*M* in the culture media. Carbohydrate increased three fold in the low nitrate algae, and protein and lipid were reduced slightly compared to the control. The
low protein:energy ratio (0.1 to 0.2) of the low nitrate diets resulted in a delay in the development of the larvae compared to that of the animals fed the control diet (ratio 0.3 to 0.4). Survival was not affected by the algal diets.
Four species of algae (*Tetraselmis suecica*, *Chaetoceros muelleri*, Tahitian *Isochrysis* sp. (T-iso) and *Dunaliella tertiolecta*) differing predominantly in their fatty acid composition were fed to *P. japonicas* larvae as single species diets. The two best diets (in terms of growth
and survival of the prawn larvae) were subsequently fed in combination to *P. semisulcatus* and *P. monodon* larvae to assess their nutritional value as part of a mixed diet. The survival and development to mysis 1 (M1), i.e. performance, of the larvae was affected by the algal diets
such that the diets could be ranked: *C. muelleri* > *T. suecica* > *Isochrysis* sp. (T-iso) > *D. tertiolecta*. The fatty acid profiles of the algae, particularly those of arachidonic acid (20:4n-6) and eicosapentaenoic acid (20:5n-6), were related to those of the larvae and
their performance. The presence of both of these fatty acids in the algal diet was necessary to produce high performance whereas docosahexaenoic acid (22:6n-3) was not. The low requirements for the PUPAs 18:2n-6 and 18:3n-3 were modulated by the presence of HUFAs such as 20:4n-6, 20:5n-6 and 22:6n-3. Therefore when these HUFAs were present in the diet, less 18:2n-6 and 18:3n-3 were required. However high proportions of 18:2n-6 and 18:3n-3 alone, did not
replace the requirements for 20:4n-6, 20:5n-6 and 22:6n-3.
Understanding the nutritional requirements of penaeid prawn larvae will lead to the production of a cost effective and optimum diet for use in hatcheries. In addition, this research will contribute to the production of a purified artificial diet for penaeid prawn larvae which can be used to examine the requirements for other nutrients.
33
Vallon, Olivier. "Organisation supramoléculaire des domaines membranaires engagés dans la communication intercellulaire (cristallin de bovidé) et dans la photosynthèse (membrane des thylakoïdes) : étude immunocytochimique." Paris 6, 1986. http://www.theses.fr/1986PA066275.
Full textAbstract:
Nous avons applique des méthodes immunocytochimiques à l'analyse des domaines membranaires dans deux systèmes différents : la membrane plasmique des cellules du cristallin de bovidé et la membrane des thylakoïdes. Dans le premier système, nous montrons que la mp26, protéine majoritaire des jonctions communicantes des fibres, est aussi présente dans les domaines non fonctionnels de la membrane plasmique des fibres, et absente de la membrane plasmique des cellules épithéliales du cristallin. La membrane des thylakoïdes, quant à elle, comporte deux domaines de compositions bien distinctes: les régions accolées renferment l'essentiel du photosystème II et de son antenne, alors que le photosystème I, l'atpase et, à moindre degré, la ferrédoxine NADP-réductase sont ségréges dans les régions non accolées de la membrane. Le cytochrome b6/f est présent dans les deux domaines. Par ailleurs, nous avons étudié l'accessibilité aux anticorps sur les faces interne et externe de la membrane de divers polypeptides de la membrane des thylakoïdes.
34
Bricheux, Geneviève. "Etude biochimique et immunologique des proteines du complexe membrane-cytosquelette des euglenes." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF21048.
Full textAbstract:
Mise au point d'un protocole de solubilisation des proteines epiplasmiques chez les euglenes et d'isolement des membranes plasmiques. Caracterisation biochimique et immunologique des proteines epiplasmiques majeures (masse moleculaire 70-90 kd); des immunserums ont permis de mettre en evidence des parentes antigeniques entre les proteines epiplasmiques d'une meme espece, d'especes differentes et de differents groupes de protistes (cilies, dinoflagelles, flagelles eugleniens)
35
Drewery, Merritt Leanne 1989. "Post-Extraction Algal Residue as a Protein Source for Cattle Consuming Forage." Thesis, 2012. http://hdl.handle.net/1969.1/148191.
Full textAbstract:
Four studies were conducted to evaluate the potential for post-extraction algal residue (PEAR) to be incorporated as a protein source in the grazing sector of the beef cattle industry. In Experiment 1, blends of PEAR and conventional protein supplements (dried distillers’ grains, DDG; cottonseed meal, CSM) were offered to steers consuming Bermudagrass to evaluate palatability of PEAR. Supplement completion, time required for consumption, and amount of supplement consumed were recorded. In Experiment 2, isonitrogenous amounts of PEAR and CSM (100 mg N/kg BW) were supplemented to steers consuming low-quality forage to compare effects on nutrient utilization. Experiment 3 evaluated the optimal inclusion rate of PEAR to steers consuming low-quality forage. Treatments included no supplemental protein, 3 levels of PEAR (50, 100, and 150 mg N/kg BW) and 1 level of CSM (100 mg N/kg BW). In Experiment 4, the effects of upstream operations on the nutritive value of PEAR were quantified.
Observations indicate PEAR may be blended with existing protein sources in the beef industry without negatively affecting palatability, but there may be palatability concerns when PEAR is offered alone. Provision of 100 mg N/kg BW of PEAR or CSM stimulated forage intake (P ≤ 0.05) and increased N retention (P = 0.02) relative to unsupplemented animals. Imbalances in mineral intakes (Ca:P ratio of 8:1) were observed when PEAR was supplemented, but not CSM. Total digestible OM intake (TDOMI) responded quadratically (P = 0.01) to increasing provision of PEAR with maximization occurring when PEAR was provided at 100 mg N/kg BW. There was not a difference in TDOMI (P = 0.13) at isonitrogenous levels of PEAR and CSM, indicating forage utilization was stimulated to a similar extent. Excess mineral levels and imbalances in PEAR were largely a result of cultivation, harvesting, and extraction procedures which could be controlled. Thus, there is potential to alter production streams to optimize oil yield and co-product value. Overall, our results indicate PEAR can be incorporated as a protein source in the beef cattle industry, thus increasing economic viability of biofuel production from algal biomass.
36
Mniki, Nontle Catherine. "Protein phosphatase biosensor for the detection of cyanotoxins associated with algal bloom." 2013. http://hdl.handle.net/11394/3628.
Full textAbstract:
Magister Scientiae - MScThe toxicity of microcystin is associated with the inhibition of serine/threonine protein phosphatases 1 and 2A, which can lead to hepatocyte necrosis and haemorrhage. Analysis of microcystin is most commonly carried out using reversed-phase high performance liquid chromatographic methods (HPLC) combined with ultra-violet (UV) detection .The ability of these techniques to identify unknown microcystin in environmental samples is also restricted by the lack of standard reference materials for the toxins. Highly specific recognition molecules such as antibodies and molecularly imprinted polymers (MIPs) have been employed in the pre-concentration of trace levels of microcystin from water and show great potential for the clean-up of complex samples for subsequent analysis. New biosensor technologies are also becoming available, with sufficient sensitivity and specificity to enable rapid ‗on-site‘ screening without the need for sample processing. In this work we constructed a Protein phosphatase biosensor for detection of microcystin-LR in aqueous medium, onto polyamic acid/graphene oxide (PAA: GO) composite electrochemically synthesised in our laboratory. The composites were synthesised at three different ratios i.e. 50:50, 80:20 and 20:80 to evaluate the effect of each component in the search to produce highly conductive mediator platforms. The electrochemistries of the three different composites were evaluated using CV and SWV to study interfacial kinetics of the materials as thin films at the glassy carbon electrode. The phosphatase biosensor parameters were evaluated using CV, SWV, EIS and Uv-vis spectroscopy. The affinity binding of the microcystin-LR to protein phosphatase 2A was investigated using electrochemical impedance spectroscopy which is a highly sensitive method for measuring interfacial kinetics of biosensor systems.
37
Rozon, Robin. "Diversity and Dynamics of Algal Viruses in the Bay of Quinte." Thesis, 2013. http://hdl.handle.net/1807/35677.
Full textAbstract:
To initiate algal virus research in the Bay of Quinte, three stations were sampled biweekly throughout 2011. By targeting algal virus DNA polymerase, major capsid protein genes (MCP), and a Microcystis aeruginosa cyanophage (Ma-LMM01) tail sheath protein gene, PCR amplification revealed diverse and unique Phycodnaviruses (viruses of eukaryotic algae) and cyanophage. When analysed statistically, patterns of virus abundance suggested that the seasonality of any one virus cannot be generalised to predict that of other viruses, even among closely related viruses. This study also demonstrated a strong relationship between algal virus abundance and host biomass. It was found that despite the apparent heterogeneity of virus abundance across the Bay, virus abundance patterns clustered by sampling date and geographic location. By providing evidence for diverse algal viruses with complex seasonality, this work highlights significant gaps in the current understanding of Bay of Quinte phytoplankton ecology.
38
Simona, Fabia. "Application of Quantitative Phosphoproteomics to the Study of Cnidarian-Dinoflagellate Symbiosis." Diss., 2019. http://hdl.handle.net/10754/631956.
Full textAbstract:
Corals are cnidarian animals that build the founding structures of tropical reefs, which survival depends upon the obligate symbiotic association to photosynthetic dinoflagellate algae in the family Symbiodiniaceae. As corals are facing increasing environmental and anthropogenic stress, understanding the molecular principles governing this unique symbiotic association is crucial to predict their adaptive potential. Due to logistic, costly, and experimental difficulties of working with corals, we use the sea anemone Aiptasia (sensu Exaiptasia pallida) as a tractable model organism for the molecular study of cnidarian-algal symbiosis. A major advantage of Aiptasia is that it establishes a facultative symbiotic association with Symbiodiniaceae algae, that is, this anemone can be maintained in an aposymbiotic (symbiont-free) state, allowing for comparison of symbiotic and ‘control’ aposymbiotic processes. The main aim of this dissertation was to investigate the signaling pathways involved in the regulation of this symbiotic interaction, and in particular, phosphorylation-mediated protein signaling. Phosphorylation is indeed a major post-translational modification that mediates signal transduction within and across cells. To investigate if protein phosphorylation regulates the complex intercellular signaling that occurs between symbiotic partners, a mass spectrometry-based phosphoproteomic approach was employed. Given the novelty of this application in the field of coral reef biology, the first research chapter details the development and optimization of a protocol that allows quantification of protein phosphorylation in the sea anemone Aiptasia. This chapter includes mass spectrometric analysis in 1) data-dependent acquisition (or shotgun proteomics) for the generation of a so-called assay (spectral) library, a reference dataset that servers for 2) accurate and reproducible label-free quantification of protein phosphorylation in data-independent acquisition (DIA/SWATH-MS). In the second research chapter, the developed protocol was employed to generate a phosphopeptide assay (spectral) library for aposymbiotic and symbiotic Aiptasia, which would allow further quantification of protein phosphorylation across symbiotic conditions. We consistently quantified more than 3,000 phosphopeptides, totaling more than 1,600 phosphoproteins, across biological replicates and symbiotic conditions. Characteristic phosphoproteomic profile distinguished the two symbiotic groups and differential phosphorylation targeted biological processes that have not been previously described in the context of cnidarian-algal symbiosis, namely the phospholipase D signaling pathway and protein processing in the endoplasmic reticulum. We suggest that changes in the phosphorylation status of these signaling pathways may have a potentially relevant role in the control of an established cnidarian-algal association.
39
Barešová, Magdalena. "Vliv peptidů a proteinů produkovaných sinicí Microcystis aeruginosa na koagulaci." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-310408.
Full textAbstract:
The aim of the diploma thesis is to analyze the mechanisms involved in the coagulation of peptides and proteins contained in cellular organic matter produced by Microcystis aeruginosa, and to describe their influence on the coagulation of hydrophobic kaolin suspension. According to the results of jar tests, the coagulation effectiveness and removability of COM peptides/proteins and kaolin particles are heavily dependent on pH value which determines charge characteristics of peptides/proteins, kaolin and hydrolysis products of coagulant and therefore the prevailing mechanisms of interactions between them. Efficient coagulation and the highest removal of COM peptides and proteins were achieved in the pH range of 4-6 due to charge neutralization of peptide/protein negative surface by positively charged hydrolysis products of ferric coagulant. Peptides and proteins contributed to the coagulation of kaolin particles under the reaction conditions mentioned above, too. Charge neutralization and adsorption were found to be the dominant coagulation mechanisms under these conditions. At a low COM/Fe concentration ratio (COM/Fe < 0.33), adsorption of peptides/proteins onto ferric oxide-hydroxide particles, described as the electrostatic patch model, enabled the coagulation in the pH range of 6-8. On the...
40
"Nutritional evaluation of selected Hong Kong seaweeds as well as their protein concentrates." 2000. http://library.cuhk.edu.hk/record=b5890316.
Full textAbstract:
by Wong Ka Hing.Thesis (M.Phil.)--Chinese University of Hong Kong, 2000.
Includes bibliographical references.
Abstracts in English and Chinese.
Dedication --- p.i
Thesis committee --- p.ii
Acknowledgements --- p.iii
Abstract --- p.iv
Abstract (Chinese version) --- p.vi
Table of contents --- p.viii
List of tables --- p.xv
List of figures --- p.xviii
List of abbreviation --- p.xix
Chapter Chapter one: --- General introduction
Chapter 1.1. --- Definition --- p.1
Chapter 1.2. --- Classification --- p.2
Chapter 1.3. --- Potential food use of seaweeds --- p.7
Chapter 1.4. --- Hong Kong seaweeds --- p.10
Chapter 1.5. --- Sargassum species --- p.12
Chapter 1.6. --- Hypnea species --- p.13
Chapter 1.7. --- Ulva species --- p.14
Chapter 1.8. --- Design of research project --- p.15
Chapter Chapter two: --- "Effect of diflerent drying methods on proximate composition, amino acid profile and some physico-chemical properties of brown seaweeds, Sargassum hemiphyllum, Sargassum henslowianum and Sargassum patens"
Chapter 2.1. --- Introduction --- p.20
Chapter 2.2. --- Materials and methods --- p.23
Chapter 2.2.1. --- Sample preparation --- p.23
Chapter 2.2.2. --- Proximate analysis --- p.26
Chapter 2.2.2.1. --- Crude protein content --- p.26
Chapter 2.2.2.2. --- Ash content --- p.26
Chapter 2.2.2.3. --- Total dietary fiber (TDF) content --- p.27
Chapter 2.2.2.4. --- Crude lipid content --- p.28
Chapter 2.2.2.5. --- Carbohydrate content --- p.29
Chapter 2.2.2.6. --- Moisture analysis --- p.29
Chapter 2.2.3. --- Amino acid analysis --- p.30
Chapter 2.2.3.1. --- "Amino acids excluding cystine, methionine and tryptophan" --- p.30
Chapter 2.2.3.2. --- Cystine and methionine --- p.31
Chapter 2.2.4. --- Physico-chemical properties --- p.32
Chapter 2.2.4.1 --- Swelling capacity (SWC) --- p.32
Chapter 2.2.4.2. --- Water holding capacity (WHC) --- p.32
Chapter 2.2.4.3. --- Oil holding capacity (OHC) --- p.33
Chapter 2.2.5. --- Statistical analysis --- p.34
Chapter 2.3. --- Results and discussion --- p.34
Chapter 2.3.1. --- Proximate composition --- p.34
Chapter 2.3.2. --- Amino acid composition --- p.39
Chapter 2.3.3. --- Physico-chemical properties --- p.42
Chapter 2.3.4. --- Conclusions --- p.46
Chapter Chapter three: --- "Effect of different methods on protein extarctability, in vitro protein digestibility and amino acid profile of seaweed protein concentrates isolated from brown seaweeds, Sargassum hemiphyllum, Sargassum henslowianum and sargassum patens"
Chapter 3.1. --- Introduction --- p.48
Chapter 3.2. --- Materials and methods --- p.51
Chapter 3.2.1. --- Sample preparation --- p.51
Chapter 3.2.2. --- Extraction of seaweed protein concentrates --- p.51
Chapter 3.2.3. --- Precipitation of seaweed protein concentrates --- p.52
Chapter 3.2.4. --- Crude protein content analysis --- p.53
Chapter 3.2.5. --- Extraction of total phenolic compounds --- p.53
Chapter 3.2.6. --- Determination of total phenolic compounds --- p.54
Chapter 3.2.7. --- In vitro protein digestibility --- p.55
Chapter 3.2.8. --- Amino acid analysis --- p.56
Chapter 3.2.9. --- Statistical analysis --- p.56
Chapter 3.3. --- Results and discussion --- p.56
Chapter 3.3.1. --- Effect of oven- or freeze-drying on protein extractability from seaweeds --- p.57
Chapter 3.3.1.1. --- Total crude protein and total phenolic content in seaweeds --- p.57
Chapter 3.3.1.2. --- "%Nitrogen, %protein, sample dry weight, amount of protein extracted and %yield of PCs" --- p.60
Chapter 3.3.2. --- Effect of oven- and freeze-drying on protein quality of seaweed PCs --- p.62
Chapter 3.3.2.1. --- Total phenolic content and in vitro protein digestibility of seaweed PCs --- p.62
Chapter 3.3.2.2. --- Amino acid composition --- p.64
Chapter 3.3.3. --- Conclusions --- p.67
Chapter Chapter four: --- "Proximate composition, amino acid profile and some physico- chemical properties of some red (Hypnea charoides and Hypnea japonica) and green seaweeds (Ulva lactuca)"
Chapter 4.1. --- Introduction --- p.68
Chapter 4.2. --- Materials and methods --- p.71
Chapter 4.2.1. --- L Sample preparation --- p.71
Chapter 4.2.2. --- Proximate analysis --- p.71
Chapter 4.2.3. --- Amino acid profile --- p.73
Chapter 4.2.4. --- Physico-chemical properties --- p.73
Chapter 4.2.5. --- Statistical analysis --- p.74
Chapter 4.3. --- Results and discussion --- p.74
Chapter 4.3.1. --- Proximate composition --- p.74
Chapter 4.3.2. --- Amino acid composition --- p.78
Chapter 4.3.3. --- Physico-chemical properties --- p.81
Chapter 4.3.4. --- Conclusions --- p.86
Chapter Chapter five: --- In vitro protein digestibility and amino acid profile of seaweed protein concentrates isolated from some red (Hypnea charoides and Hypnea japonica) and green seaweeds (Ulva lactuca)
Chapter 5.1. --- Introduction --- p.88
Chapter 5.2. --- Materials and methods --- p.89
Chapter 5.2.1. --- Sample preparation --- p.89
Chapter 5.2.2. --- Extraction and precipitation of seaweed PCs --- p.90
Chapter 5.2.3. --- Crude protein analysis --- p.90
Chapter 5.2.4. --- Extraction and determination of total phenolic contents --- p.90
Chapter 5.2.5. --- In vitro protein digestibility --- p.91
Chapter 5.2.6. --- Amino acid analysis --- p.92
Chapter 5.2.7. --- Statistical analysis --- p.92
Chapter 5.3. --- Results and discussion --- p.93
Chapter 5.3.1. --- Protein extractability --- p.93
Chapter 5.3.1.1. --- Crude protein and total phenolic contentin seaweeds --- p.93
Chapter 5.3.1.2. --- "%Nitrogen, %protein, sample dry weight, amount of protein extracted and %yield of PCs" --- p.95
Chapter 5.3.2. --- Protein quality --- p.97
Chapter 5.3.2.1. --- Total phenolic content and in vitro protein digestibility of seaweed PCs --- p.97
Chapter 5.3.2.2. --- Amino acid composition --- p.99
Chapter 5.3.3. --- Conclusions --- p.103
Chapter Chapter six: --- Biological evaluation on protein quality of seaweed protein concentrates isolated from Hypnea charoides and Hypnea japonica
Chapter 6.1. --- Introduction --- p.104
Chapter 6.2. --- Materials and methods --- p.114
Chapter 6.2.1. --- Sample preparation --- p.114
Chapter 6.2.2. --- Extraction and precipitation of seaweed protein concentrates --- p.114
Chapter 6.2.3. --- Diet preparation --- p.115
Chapter 6.2.4. --- Rat bioassay --- p.117
Chapter 6.2.5. --- Biological indices --- p.118
Chapter 6.2.6. --- Statistical analysis --- p.119
Chapter 6.3. --- Results and discussion --- p.119
Chapter 6.3.1. --- Protein quality of seaweed PCs --- p.119
Chapter 6.3.2. --- Weight of major organs --- p.126
Chapter 6.3.3. --- Conclusions --- p.129
Chapter Chapter seven: --- Functional properties of protein concentrates isolated from Hypnea charoides and Hypnea japonica
Chapter 7.1. --- Introduction --- p.130
Chapter 7.2. --- Materials and methods --- p.136
Chapter 7.2.1. --- Sample preparation --- p.136
Chapter 7.2.2. --- Preparation of protein concentrates --- p.137
Chapter 7.2.3. --- Nitrogen solubility --- p.137
Chapter 7.2.4. --- Water and oil holding capacity --- p.138
Chapter 7.2.5. --- Viscosity --- p.139
Chapter 7.2.6. --- Emulsifying activities and emulsion stability --- p.140
Chapter 7.2.7. --- Foam capacity and foam stability --- p.141
Chapter 7.2.8. --- Statistical analysis --- p.142
Chapter 7.3. --- Results and discussion --- p.142
Chapter 7.3.1. --- Nitrogen solubility --- p.142
Chapter 7.3.2 --- Wafer and oil holding capacity --- p.145
Chapter 7.3.3. --- Viscosity --- p.147
Chapter 7.3.4 --- Emulsifying activities and emulsion stability --- p.149
Chapter 7.3.5. --- Foam capacity and foam stability --- p.153
Chapter 7.3.6. --- Conclusions --- p.157
Chapter Chapter 8: --- Conclusions --- p.158
References --- p.160
Appendix --- p.195
Related publications --- p.202
41
Kaczmarzyk, Danuta. "Acyl-acyl carrier protein synthetases from bluegreen algae and plants." Doctoral thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-0006-B652-B.
Full text
42
Tobón, Quiala Ana Luz. "Efecto de la luz azul sobre la sintesis proteica en microalgas." 1985. http://catalog.hathitrust.org/api/volumes/oclc/24859853.html.
Full text
43
Huang, Chih-Cheng, and 黃至正. "Study of protein-peptide binding affinity with AlGaN/GaN high electron mobility transistors." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/12662929000315035917.
Full text
44
Kaczmarzyk, Danuta [Verfasser]. "Acyl-acyl carrier protein synthetases from bluegreen algae and plants / vorgelegt von Danuta Kaczmarzyk." 2008. http://d-nb.info/993188168/34.
Full text
45
趙致忠. "Purification of UV and Cisplatin Binding Proteins from Unicellular Algae Chlorella Pyrenoidosa." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/35181774593230619998.
Full text
46
Ho, Jhon-Chung, and 何炯昌. "Purification of UV-damaged-DNA Binding Proteins from Unicellular Algae Chlorella pyrenoidosa." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/97468926260343466979.
Full text
47
Kuo, Jung-Lieh, and 郭榮烈. "Studies on the transferrin-like protein and gene of the green alga Dunaliella tertiolecta." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/63045349201840486614.
Full textAbstract:
博士國立臺灣大學
海洋研究所
88
The role of iron in the growth and physiology of the marine alga Dunaliella tertiolecta was investigated. Comparison of the electrophoretic profiles of total proteins from cells grown under iron-replete or iron-deficient conditions revealed that the abundance of a 38-kDa protein was markedly increased in cells deprived of iron. Electron microscopy also revealed that cells subjected to iron limitation exhibited substantial chlorosis and a defective photosynthetic apparatus. In addition, immunoblot analysis showed that iron deprivation increased the abundance of a 150-kDa protein that reacts with antibodies to human transferrin. With the use of the polymerase chain reaction and primers based on the nucleotide sequence of a gene for a transferrin-like protein in D. salina, a 9.5-kb fragment of D. tertiolecta genomic DNA that encodes a homologous protein was isolated and sequenced. The Dunaliella tertiolecta gene comprises 30 exons and contains an open reading frame of 3825 bp that encodes a protein of 1274 amino acids. The predicted amino acid sequence of the encoded protein shows a high degree of homology to those of various transferrin proteins from other organisms.
48
Mahadevaswamy, M. "Production of blue green alga spirulina platensis for biomass protein in clean water and integrated systems." Thesis, 1994. http://hdl.handle.net/2009/2989.
Full text
49
Leandro, Filipa Ferreira. "Effects of thermal stress on the photoinactivation and repair of photosystem II in a xanthophyll cycledeficient green alga." Master's thesis, 2021. http://hdl.handle.net/10773/33639.
Full textAbstract:
Photosynthesis and primary productivity are very temperature-dependent.
Extremely high or low temperatures affect the enzymatic mechanisms of
photoprotection (xanthophyll cycle) and exacerbate the photo-imaging effects
of high light on photosystem II (PSII). A recently proposed hypothesis states
that abiotic stress, including mild cold and heat, enhances photoinhibition of
photosynthesis not by directly damaging the PSII, but by inhibiting repair
mechanisms. This work intends to test this hypothesis in an as yet unexplored
group of green algae (Bryopsidales) without a xanthophyll functional cycle.
In order to test this hypothesis, we used the measurement of chlorophyll
fluorescence, under light and thermal stress, and subsequent quantification of
D1 protein, using the Western blot technique. Our findings showed that for this
group of algae, the aforementioned hypothesis is not applicable, as the abiotic
stresses affected not only repair mechanisms but also exacerbated
photoinhibition. Consequently, the group of green algae (Bryopsidales)
showed great potential for future studies in the scope of the investigation
regarding repair mechanisms of photosystem II.A fotossíntese e a produtividade primária dependem profundamente da temperatura. Temperaturas extremamente altas ou baixas afetam os mecanismos enzimáticos de fotoproteção (ciclo das xantofilas) e exacerbam os danos provocados pela irradiação elevada no fotossistema II (PSII). Uma hipótese recentemente proposta afirma que o stress abiótico, incluindo frio e calor moderado, aumenta a fotoinibição da fotossíntese não por efeitos diretos no PSII, mas sim pela inibição dos mecanismos de reparação. Este trabalho pretende testar essa hipótese num grupo ainda inexplorado de algas verdes (Bryopsidales) que não possuem um ciclo das xantofilas funcional. Para testar esta hipótese, recorremos a medições da fluorescência da clorofila a, sob stress luminoso e térmico, e posterior quantificação da proteína D1, através da técnica do Western blot. Os nossos resultados mostraram que, para este grupo de algas, a hipótese acima mencionada, não é aplicável, pois os stresses abióticos afetaram não apenas os mecanismos de reparo, mas também exacerbaram a fotoinibição. Consequentemente, o grupo de algas verdes (Bryopsidales) apresentou um grande potencial para futuros estudos no âmbito da investigação dos mecanismos de reparação do fotossistema II.
Mestrado em Biologia Aplicada
50
Duarte, Mariana Caiado Roseta. "Perspetivas futuras para a sustentabilidade alimentar : novas fontes de proteína na alimentação dos portugueses." Master's thesis, 2018. http://hdl.handle.net/10400.14/26585.
Full textAbstract:
O crescimento da população mundial traz consigo novos desafios uma vez que implica um
aumento da produção de alimentos numa quantidade limitada de solo arável. A transição de
dietas ricas em produtos de origem animal para dietas ricas em alternativas mais ecológicas será
crucial tanto em termos de sustentabilidade ambiental como de saúde humana. Assim, o
objetivo deste trabalho foi caraterizar o consumo atual de leguminosas, algas e insetos numa
amostra da população adulta portuguesa, avaliar a sua predisposição para a inclusão destas
alternativas alimentares e identificar os conhecimentos, as motivações e as barreiras para o
consumo de leguminosas em Portugal. Numa abordagem quantitativa, aplicou-se um
questionário semiestruturado, divulgado online e obtiveram-se 1741 respostas válidas
(residentes em Portugal, ≥ 18 anos). Os participantes eram maioritariamente do sexo feminino
(71,4%) com idade média de 27,2 ± 9,9 anos. A maioria (62,0%) frequentava o ensino
universitário ou possuía formação superior. As leguminosas mais consumidas (≥1x/semana)
foram o feijão (48,3%) e a ervilha (44,4%). Em relação às algas/microalgas, 41,8% referiu
nunca as ter experimentado e entre os que experimentaram, as mais consumidas eram a Nori e
a Spirulina. Relativamente aos insetos, 94,8% nunca os tinha experimentado e, destes, somente
26,5% colocava a hipótese de os vir a consumir. No que respeita às leguminosas, 15,0%
assumiu que não coloca a hipótese de vir a utilizá-las como substitutos da carne e do peixe,
enquanto 19,9% já o faziam. Relativamente às algas/microalgas, 41,5% afirmaram que lhes
custaria muito fazer esta substituição. Em relação aos insetos, 87,7% referiu que esta
substituição lhes custaria muito a realizar ou que nem sequer ponderariam essa hipótese, mesmo
num cenário de escassez de alimento. Numa abordagem qualitativa, realizaram-se 10
entrevistas individuais com o objetivo de estudar o comportamento e as experiências pessoais
associadas ao consumo de leguminosas. Apurou-se que a falta de reconhecimento do seu valor
nutricional, o elevado tempo de confeção e o efeito dos compostos anti-nutricionais presentes
neste alimento são comummente apontados para o não consumo. Os portugueses não estão
muito recetivos à possibilidade e necessidade atual de substituição de carne e pescado pelas
“proteínas do futuro”. Dentre as opções alimentares avaliadas, as leguminosas são o grupo mais
popular e a alternativa cuja aceitação parece ser mais consensual. Em oposição, os insetos são
a fonte de proteína menos aceite. A identificação das barreiras ao consumo destas “novas”
alternativas deverá ser tida em consideração para o desenvolvimento de novas estratégias de
promoção do seu consumo alimentar.World population growth brings with it new challenges as it implies an increase in food production in a lower amount of arable land. The transition from meat and fish based diets to diets with high content in other ecological alternatives will be crucial for both environmental sustainability and human health. The aim of this study was to characterize the current consumption of legumes, algae and insects in a sample of the Portuguese adult population, to describe the drivers to include these as food alternatives and to identify the knowledge, motivations and barriers for legumes intake, in Portugal. Using a quantitative approach, a semistructured questionnaire was disclosed online, and 1174 valid responses were obtained (Portuguese residents, ≥ 18 years). Respondents were mostly female (71.4%) and had a mean age of 27.2 ± 9.9 years). The majority of participants (62.0%) attended university education or had higher education. The most consumed legumes were beans and peas, consumed ≥1x / week by 48.3% and 44.4% of the sample, respectively. Regarding algae / microalgae, 41.8% reported never having tried them and, among those who experimented, the most consumed were Nori and Spirulina. Concerning insects, 94.8% had never tried them and, within this group, only 26.5% place the hypothesis of this substitution. For all the alternatives it was asked if they consider using them as substitutes for meat and fish. Regarding legumes, 15.0% stated they would not substitute, 42% answered that it would be easy for them to do so and 19.9% already did. Regarding algae / microalgae, 41.5% stated that it would be very difficult for them to do so and only 3.3% already did. Regarding insects, 87.7% said it would be difficult to do this substitution or would not even consider this hypothesis even in a food scarcity scenario. In the qualitative study, ten individual interviews were conducted in order to study individual behaviors and experiences linked to legumes’ consumption. Regarding the barriers to the consumption of legumes (the most accepted source of alternative protein among the Portuguese population), it was noticed that the lack of recognition of their nutritional value, the high cooking time and the effect of the anti-nutritional factors present in this food are commonly pointed out. Portuguese population is not prepared to the possibility and current need to replace meat and fish with the "future proteins". Among the food options evaluated, legumes are the most popular group and the alternative whose acceptance seems to be more consensual. In contrast, insects are the least accepted source of protein. The identification and understanding of perceived barriers for that low consumption will make it easier to develop new strategies to promote these "new" alternatives’ intake.