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Kalaitzis, John Alexander. "Chemical Investigations of Australian Marine Sponges". Thesis, Griffith University, 2005. http://hdl.handle.net/10072/365493.
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This thesis describes the isolation and structure elucidation of a series of natural products from six different marine sponges collected from Australian waters. A total of nineteen sponge metabolites were isolated, four of which had not been reported previously. The structures of these compounds were elucidated by spectroscopic methods. An investigation into two sponges from the Adocia genus revealed a series of novel compounds related to the proton pump inhibitor adociasulfate 1 (3.22). Adociasulfates 7 (3.24) and 8 (3.25), along with adociasulfate 1 were isolated from an Adocia aculeata collected from Lizard Island. Another sample of Adocia aculeata collected from Cormorant Pass, North Great Barrier Reef, yielded adociasulfates 5 (3.23) and 9 (3.26). In the course of the study it was found that the adociasulfates were present only in the extracts of Adocia aculeata samples and not other Adocia species, thus revealing a possible chemotaxonomical relationship. The investigation of three sponges, whose extracts showed inhibition of [3H]DPCPX binding to rat-brain adenosine A1 receptors, yielded ten compounds, one of which was novel. An investigation into a Pseudoceratina sp. collected from Swain Reefs, Queensland resulted in the isolation of the new bromotyrosine derived ianthesine E (4.24) and the known related compounds aerothionin (4.20), 11-hydroxyaerothionin (4.21), 19-deoxyfistularin 3 (4.22), and 11,19-dideoxyfistularin 3 (4.23). Aerothionin was found to be the most active of this series of compounds, inhibiting 67% binding of [3H]DPCPX at 100 ìM. Interpretation of HMBC NMR spectra of these compounds and comparison with data reported previously for related bromotyrosine compounds revealed that some data in the literature had been misassigned. Investigations into a Xestospongia pacifica and a Phakellia flabellata collected from Swain Reefs resulted in the isolation of a series of five known metabolites. Debromohymenialdsine (4.71) was isolated from Phakellia flabellata and was found to be the most effective inhibitor of [3H]DPCPX binding (79% at 100ìM) to the adenosine A1 receptor of all of the compounds tested as part of this research. Also isolated from this sponge were aldisine (4.69) and norzooanemonin (4.70). 1,3-dimethylguanine (4.48) was isolated from Xestospongia pacifica, and this compound showed 61% inhibition of [3H]DPCPX binding to the adenosine A1 receptor at 100ìM. N-methyltaurine (4.55) was also isolated from this sponge in a crystalline form. The XRD analysis of the crystal revealed extensive hydrogen bonding interactions between the amine H atoms and sulfonyl O atoms in the zwitterionic molecule. Chemical investigation of a Mycale sp. collected from Stephen's Rock, Darwin, Northern Territory resulted in the isolation of the nucleosides uridine (5.13), 2'- deoxyuridine (5.14), 2'-deoxyinosine (5.16) and the pyrimidine base thymine (5.15). Uridine and 2-deoxyinosine were tested for inhibition of [3H]DPCPX binding to adenosine A1 receptors. Uridine inhibited 45% of binding at 100ìM while 2- deoxyinosine inhibited 34% binding at the same concentration. Cytotoxicity screening of the sponge metabolites against the HeLa cell line revealed that 11,19-dideoxyfistularin-3 with an EC50 of 2.6 ìM was the most potent cytotoxin of all of the compounds isolated. Aerothionin was the next potent with an EC50 of 42 ìM while adociasulfate 8 was found to be the most cytotoxic of the four adociasulfates screened with an EC50 of 68 ìM.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Eskitis Institute for Cell and Molecular Therapies
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Mokhlesi, Amin [Verfasser]. "Natural Products from Marine Sponges / Amin Mokhlesi". Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2018. http://d-nb.info/1154306984/34.
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Park, Young Chul. "Chemical Investigation of Three Antarctic Marine Sponges". Scholar Commons, 2004. https://scholarcommons.usf.edu/etd/1190.
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This thesis describes the chemical investigation of three marine sponges from Antarctica and the total syntheses of natural products erebusinone (12) and its derivative, erebusinonamine (52). Investigation of the yellow Antarctic marine sponge Isodictya setifera resulted in the isolation of two secondary metabolites, purine analog (32) and 3-hydroxykynurenine (24). Chemical investigation of Isodictya setifera led to the isolation of six secondary metabolites which included 5-methyl-2-deoxycytidine (25), uridine (28), 2-deoxycytidine (31), homarine (37), hydroxyquinoline (33), 3-hydroxykynurenine (24). The latter two compounds were found to be intermediates of tryptophan catabolism in crustaceans. From the Antarctic marine sponge Isodictya antractica ceramide analog (39) was isolated and its chemical structure was assigned by a combination of spectroscopic and chemical analyses. Stereochemistry was determined by modified Mosher's method. Erebusinone (12), a yellow pigment isolated from the Antarctic marine sponge Isodictya erinacea has been implicated in molt inhibition and mortality against the Antarctic crustacean amphipod, Orchomene plebs, possibly serving as a precursor of a xanthurenic acid analog.
Thought to act as a 3-hydroxykynurenine 24 mimic, erebusinone (12) may be involved chemical defense. This appears to be the first example in the marine realm of an organism utilizing tryptophan catabolism to modulate molting as a defensive mechanism. To further investigate the bioactivity and ecological role of erebusinone (12), the synthesis of this pigment was carried out in an overall yield of 44% involving seven steps which were economical and convenient. Erebusinonamine (52) was also similarly synthesized in eight steps with an overall yield of 45%.
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Gautschi, Jeffrey T. "Marine natural products from sponges and deep water, marine-derived fungi /". Diss., Digital Dissertations Database. Restricted to UC campuses, 2006. http://uclibs.org/PID/11984.
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Roper, Kathrein Elizabeth. "Cellular and molecular targets of allelochemicals from marine sponges /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19101.pdf.
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Tabudravu, Jioji N. "Investigations of secondary metabolites from Fijian marine sponges". Thesis, University of Aberdeen, 2001. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602042.
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The following thesis presents results from investigations of marine natural products. It is divided into 7 chapters consisting of an introduction, five chapters examining the metabolites from Fijian marine sponges and one chapter examining the secondary metabolites from the medicinal plant, kava {Piper methysticum). Two new psammaplins (psammaplin K and L), a new isomalabaricane triterpene monosaccharide, two new bromotyrosine alkaloids (purealidin S and purpureamine J) and two new cyclic peptides (axinellin C and wainunuamide), a new conformer of phakellistatin 2 together with other known secondary metabolites were isolated from marine sponges. The new conformer of phakellistatin 2 was observed to adopt another conformation in CDCI3. Psammaplin A was found to inhibit chitinase from a Bacillus sp. and Serratia marcescens. The mode of activity was investigated by enzyme reaction kinetics and supported by X-ray crystallography. A new isomer of flavokavain A, woflavokavain A was isolated from kava, together with 7 known compounds. Solution conformations of axinellin C, jasplakinolide, phakellistatin 2 and its two conformers were generated using nOe restrained molecular modelling techniques.
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Schmidt, Eric Whitney. "Marine sponges and symbionts : chemical and biological studies /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1999. http://wwwlib.umi.com/cr/ucsd/fullcit?p3035433.
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BASSOTTI, ELISA. "Heavy metals in marine organisms. Mediterranean and Antarctic marine sponges and bivalves". Doctoral thesis, Università Politecnica delle Marche, 2010. http://hdl.handle.net/11566/242161.
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Kim, Tae Kyung. "Bioactive compound-producing symbiotic bacteria from marine sponge species : cultural, gene retrieval, and metagenomic studies /". [St. Lucia, Qld.], 2006. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19506.pdf.
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Antunes, Edith Martins. "Pyrroloiminoquinone metabolites from South African Latrunculid sponges". Thesis, Rhodes University, 2003. http://eprints.ru.ac.za/215/.
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Segraves, Nathaniel Lee. "Chemical investigation of biologically active alkaloids from marine sponges /". Diss., Digital Dissertations Database. Restricted to UC campuses, 2005. http://uclibs.org/PID/11984.
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Mani, Luke. "Antiplasmodial compounds from marine sponges of the Solomon Islands". Toulouse 3, 2010. http://www.theses.fr/2010TOU30280.
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Dans le cadre de la recherche de nouvelles molécules antipaludiques, une espèce d'Haliclona et quatre lots de l'éponge Aplysina ianthelliformis ont été étudiées pour fournir 22 composés, dont sept sont nouveaux 141-147. Un produit connu, l'haliclonacyclamine A 129, qui a montré ici une activité in vitro sur des souches de Plasmodium falciparum FCB1 résistantes à la chloroquine avec une CI50 de 98nM et un index de sélectivité (activité Antipalsmodiale/cytotoxicité) de 57 et 67 déterminé respectivement sur cellules MVF7 et Véro. Testée in vivo sur le modèle souris, l'haliclonacyclamine A 129 a montré 48% d'inhibition de la parasitémie le 4ème jour après 3 jours de traitement à 10mg/Kg/jour administré par voie intra-péritonéale à des souris Swiss femelles infectées par P. Vinckei petteri. Les échantillons d'A. Ianthelliformis ont fourni 21 produits, tous sauf deux (aureol 137 et aplysterol 138) appartenant à la série des bromotyrosines. Ces composés 35a, 36, 130-147 montrent une faible activité in vitro sur les souches résistantes ou sensibles à la chloroquine, P. Falciparum FCB1 et 3D7 respectivement, avec des CI50 allant de 0. 9 à 44µM. Tous les composés dérivés de la bromotyrosine manquent de sélectivité, sauf l'araplysillin I 139 qui présente un faible index de sélectivité de 5,5 et 6,5 respectivement sur cellules MCF7 et Vero, et une CI50 = 4,5µM sur P. Falciparum FCB1. Tous ces produits présentent une faible activité sur la Protéinefarnésyletransférase (PFTase) ; le composé le plus actif, l'aerophobin II 135, a une CI50 = 4. 9µM. L'inactivité de la molécule 144 suggère l'importance du motif isoxazolinique dans l’activité sur PFTaseIn a search for new antiplasmodial compounds, one Haliclona and four Aplysina ianthelliformis sponges were chemically investigated to furnish 21 compounds, seven of which are novel ones 141-147. The Haliclona sponge gave the known product, haliclonacylamine A 129 which exhibits potent in vitro activity against the chloroquine-resistant strain, Plasmodium falciparum FCB-1 with an IC50 of 98 nM and a strong selectivity index of 57 and 67 (determined as antiplasmodial activity/ cytotoxicity). In the in vivo mice model, haliclonacyclamine A 129 gave 45% parasitaemia inhibition on the fourth day following three days of treatment at 10 mg/Kg/day administered intra-peritoneally to Swiss female mice infected with P. Vinckei petteri. The A. Ianthelliformis sponges furnished 20 compounds, all but two (aureol 137 and aplysterol 138) of which are bromotyrosine derivatives. All bromotyrosine-derived compounds; 35a, 36, 130-147 exhibit mild in vitro activities against the chloroquine-resistant and sensitive strains, P. Falciparum FCB-1 and 3D7 respectively, with IC50s ranging between 0. 9 – 50. 5 µM. All bromotyrosine compounds lack selectivity except for araplysillin I 139 which has a weak selectivity index of 5. 5 and 6. 5 (measured for MCF-7 and Vero cells respectively) and an IC50 value of 4. 5 µM against P. Falciparum, FCB-1. All bromotyrosine derivatives, except for the novel compound 144, also exhibit weak Protein farnesyltransferase (PFTase) inhibitory activity; the most active, aerophobin II 135, has an IC50 of 8. 0 µM. The inactivity of compound 144 suggests the importance of the isoxazoline motif in conferring PFTase activity in bromotyrosine compounds
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Romeril, Stuart P. "Synthesis and structural elucidation of the Bis-3-alkylpyridine alkaloid pyrinodemin A and other monomeric alkaloids". Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288526.
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López, Acosta María. "Silicon consumption by marine sponges: an empirical approach and its ecological implications". Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663476.
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Silicon (Si), in its dissolved form of silicic acid (DSi), is a key nutrient in the ocean. The availability of such nutrient in marine ecosystems is regulated through its use by silica-secreting organisms, a variety of groups including protists, algae, and animals that consume DSi to build their silica (BSi) skeletons. The interest in determining how Si cycles in the ocean is high, since it interacts with the cycling of other major nutrients and ocean primary productivity. Because diatoms are the most abundant Si users, the scientific attempts to quantify the Si utilization in the ocean have been only focused on these organisms, considering negligible the role of other Si users. Over the last decades, some studies have suggested that at least another group, the siliceous sponges, are also playing a non-negligible role in the consumption of Si in marine ecosystems.
Marine sponges are conspicuous animals in benthic ecosystems. They are common across the world ocean, irrespective of the latitude and depth, being able to form enormous aggregations that may extend over large areas. Both their ubiquity and their abundance make sponges good candidates to develop relevant functional roles in marine ecosystems. Regarding the use of Si, it is surprising that, despite about 80% of the sponge species require from DSi to elaborate their skeleton, almost no information is available about how sponges consume such nutrient. In fact, before the beginning of this PhD, only few studies had investigated DSi consumption in marine sponges, with kinetic models available for only four species in two genera of demosponges. This lack of knowledge sparked this PhD, which has been developed in the frame of three research grants: 1) “A research action to quantify fluxes and sinks of silicon through sponges: a neglected circuit within the marine cycle” (MEC–CTM2012-37787); 2) “Exploring the biological production of silica and its applications in science and technology” (MINECO-CTM2015-67221- R); and 3) WP4 —Ecosystem functions, services, and goods— in the EU’s project SponGES (H2020-No. 679849). The main objective of the work was to improve the general understanding on how sponges utilize DSi, to facilitate further assessment of the quantitative role of the sponges as Si users.
Here we investigated the kinetics of DSi consumption in five sponge species: four temperate, shallow-water demosponges and, for the first time, a cold, deep-water hexactinellid sponge. We also examined the sources of between-species and between-individual variability in DSi consumption responses. Interestingly, we detected that DSi consumption kinetics can change seasonally in some species, what may have important implications when quantifying the role of sponges as Si users. Additionally, we determined for the first time the rate of DSi utilization by a sponge species in situ. The results significantly matched those estimated from the kinetic models obtained in the laboratory, supporting the use of long (>24h) incubations in laboratory to investigate DSi consumption kinetics in sponges, in contrast to the very short periods traditionally recommended for diatoms (< 3h). Finally, we used the empirically information gained on DSi consumption over the development of this PhD to estimate the utilization of DSi by a sponge assemblage at the ecosystem level, using as case study the bay of Brest (France).
In summary, this research showed that sponges have a noticeable role as Si users, even in a shallow-water ecosystem (the bay of Brest) where diatoms largely contribute to the phytoplankton biomass. Our results also indicated that sponges increase their role in marine ecosystems with increasing availability of DSi in seawater. Thus, sponges are predicted to play a relevant role as Si users in high-latitude and deep-water habitats, characterized by high DSi availability. All together, the siliceous sponges should be considered as Si users if we aim to accurately quantify the cycling of Si in marine ecosystems.El silicio (Si), en su forma disuelta de ácido silícico (DSi), es un nutriente clave en el océano. Su disponibilidad en los ecosistemas marinos la regulan varios grupos de organismos, los cuales consumen DSi para construir sus esqueletos de sílice (BSi). Debido a que las diatomeas son el consumidor de Si más abundante, los intentos por cuantificar el uso del Si en el océano se han centrado principalmente en estos organismos, considerando el papel de los otros usuarios de Si como irrelevante. Durante las últimas décadas, algunos estudios han sugerido que al menos otro grupo, las esponjas silíceas, también están jugando un papel no-despreciable en el consumo de Si en los ecosistemas marinos. Las esponjas marinas son animales abundantes en los ecosistemas bentónicos. Es sorprendente que, pese a que el 80% de las especies necesitan DSi para formar sus esqueletos, casi no existe información disponible sobre cómo las esponjas consume dicho nutriente. De hecho, antes del comienzo de esta tesis (inicios del 2014), solo unos pocos estudios habían investigado el consumo de DSi en esponjas marinas, con modelos cinéticos sólo disponibles para dos géneros de demosponjas. Así, el principal objetivo de este trabajo fue mejorar el conocimiento general de cómo las esponjas utilizan DSi, facilitando futuras cuantificaciones del papel de las esponjas como usuarias de Si. Primero, investigamos las cinéticas de consumo de DSi en cinco especies de esponjas, incluida, por primera vez, una especie de la Clase Hexactinellida. También examinamos las fuentes de variabilidad entre especies y entre individuos, detectando que en algunas especies pueden ocurrir cambios estacionales en las cinéticas de consumo. Además, determinamos por primera vez la tasa de uso de DSi en esponjas en su hábitat natural (in situ). Los resultados, significativamente concordantes con los estimados por modelos cinéticos obtenidos en el laboratorio, respaldan el uso de incubaciones largas (>24h) en el laboratorio para investigar las cinéticas de consumo de DSi en esponjas. Finalmente, usamos toda la información empíricamente obtenida durante esta tesis para estimar el uso de DSi por parte de una comunidad de esponjas al nivel de ecosistema: la bahía de Brest (Francia). En resumen, este trabajo muestra que las esponjas tienen un papel relevante como usuarios de Si, incluso en un ecosistema somero en donde las diatomeas contribuyen ampliamente a la biomasa fitoplanctónica. Nuestros resultados también indican que el papel de las esponjas en los ecosistemas marinos aumenta junto con la disponibilidad de DSi. Por tanto, se predice que las esponjas jueguen un papel importante como usuarios de Si en hábitats profundos y de latitudes altas, caracterizados por alta disponibilidad de DSi. Todo ello indica que las esponjas silíceas deben ser consideradas como usuarios de DSi si queremos cuantificar de forma precisa el ciclo del Si a través de los ecosistemas marinos.
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Yang, Lai Hung. "Antifouling compounds from the marine sponge acanthella cavernosa and its associated microbes /". View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?AMCE%202006%20YANG.
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Lerata, Mookho Sylvia. "Discovery of cytotoxic natural products from South African marine sponges". University of the Western Cape, 2018. http://hdl.handle.net/11394/6447.
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Magister Pharmaceuticae - MpharmCancer is a major health problem worldwide and killing millions of people each year. The use of natural products as chemotherapeutic agents is well established, however, many of the currently available drugs are associated with undesirable side effects and high toxicity. Furthermore, the development of drug resistant cancers makes the search for anticancer lead compounds a priority. In this study a library of prefractionated marine sponge extracts was established and used to prioritise samples for isolation of bioactive metabolites. From the generated library, two of the sponges of genera Ircinia sp. and Latrunculid sp. resulted in isolation of furanosesterterpenes (7E,12Z,20Z,18S-variabilin) and pyrroloiminoquinone (tsitsikammamine A and tsitsikammamine N-18 oxime) alkaloids respectively. The structures of these compounds were elucidated by analysis of 1D and 2D NMR data. These compounds displayed moderate to potent cytotoxicity against MCF-7, PC-3, U-87 and HEK-293 cells lines through apoptosis, with lack of selectivity for cancer cell lines.
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Griffiths, Sarah Miriam. "Molecular approaches in conservation and ecology research in marine sponges". Thesis, Manchester Metropolitan University, 2018. http://e-space.mmu.ac.uk/620378/.
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Marine ecosystems face a challenging future as a result of human activity, and as such, it is vital to understand the ecology of marine organisms in order to effectively conserve them. Increasingly, molecular ecology tools are used for this purpose. In this thesis, I developed molecular resources for the study of sponges, an ecologically important and diverse marine group. Firstly, I developed a bioinformatics pipeline for the de novo isolation of microsatellites - genetic markers used to study intraspecific genetic diversity. Using this method, I characterised microsatellites for two Tropical Western Atlantic sponge species, Ircinia campana and Spheciospongia vesparium. These species have suffered mass mortalities in Florida Bay (Florida Keys, USA), with devastating effects on the ecosystem, and are currently among the subjects of an ecological restoration program. With these microsatellites, I investigated the spatial genetic structure of populations of both species across the Greater Caribbean and within the Florida Keys. I found genetic isolation by distance patterns over the region, indicating distance-limited dispersal, and also identified oceanographic barriers to population connectivity. On smaller spatial scales, genetic structure was also present, but patterns of genetic patchiness suggested that stochastic processes were more influential in determining structure at this scale. Finally, I investigated the effect of the Ircinia campana genotype on the composition of its associated microbial community. I found that more genetically similar sponges hosted more similar microbiomes, supporting the theory of a close coevolutionary relationship, and highlighting the importance of genetic diversity within species. With these insights on the distribution and effects of genetic diversity, I discuss the implications for sponge restoration in Florida Bay, and make recommendations for conservation practitioners to ensure resilience in sponge populations.
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Hagos, Selam. "Chemical Investigation of Bioactive Marine Extracts". Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7301.
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Natural products have been a fundamental source of medicinal scaffolds for decades; with sixty percent of marketed drugs. Many synthetic chemists are focused on synthesizing potent and nontoxic compounds for pharmaceutical targets, however, nature is still proving to be a source of new bioactive compounds. Produced by the host organism for defense, reproduction and communication, secondary metabolites also demonstrate promising bioactivity against human pathogens. Hence, natural product chemists continue their quest for new leads.
As a continuation of these efforts, this thesis attempts to explore fungi and sponges for new chemistry, and ultimately, new drug candidates. Antarctica is largely untapped; hence herein two Antarctic sponges were chemically investigated. This resulted in isolation and characterization of two metabolites. Concurrently, chemical investigation of fungus, from Floridian mangrove species, resulted in the isolation of two structurally diverse metabolites. Further, a dereplication process was applied to MPLC fractions, which lead to the identification of known metabolites and mycotoxins. This enabled prioritization of fractions for future studies.
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Wren, Stephen P. "Studies towards the total synthesis of the marine-derived immunosuppressant discodermolide". Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/271996.
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Burkhart, Tandace L. "The Search for Novel Sponge genes: Comparative Analysis of Gene Expression in Multiple Sponges". NSUWorks, 2012. http://nsuworks.nova.edu/occ_stuetd/194.
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This project focuses on the use of sponge genetic transcripts in the form of expressed sequence tags (ESTs) readily available in Genbank to search for novel genes using bioinformatics analysis tools. Marine sponge species are known to house a diversity of marine microbes and are known as the ‘living fossils’ of the animal kingdom because of the large number of ancient genes they house. Genomic mining can be a useful tool in discovering these orthologous genes. This study utilized the techniques of genomic mining of 11 previously described sponge species transcripts. The results of this study provide a better understanding of the genomic structure of the organisms studied by creating a more detailed genetic map and examining a specific environmental snapshot of the genes in each sponge. Novel methods for dissecting beneficial information from large scale data sets available in genomic libraries utilizing bioinformatics search tool MGRAST were examined. The results of this study indicate that sponges house numerous genes that are likely to be evolutionary predecessors of genes in higher eukaryotes. Support was also given to the notion that microbial communities play a role in metabolic pathways of sponges.
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Firkin, Catherine R. "A biomimetic approach to the synthesis of xestospongin A". Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389208.
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McMurray, Steven E. "Demography of the giant barrel sponge Xestospongia muta in the Florida Keys". View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-3/r1/mcmurrays/stevenmcmurray.pdf.
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Turon, Rodrigo Marta. "Macro- and micro -symbioses involving sponges: Ecological roles in the marine benthos". Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/668685.
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The symbiotic lifestyle represents a fundamental contribution to the diversity of marine ecosystems. Sponges are ideal models to study symbiotic relationships from evolutionary and ecological points of view since they are the most ancient metazoans on Earth, are ubiquitous in the marine benthos, and establish complex symbiosis with both prokaryotes and animals, which in turn harbour their own bacterial communities.
In this thesis, we aim to go deeper into the mechanisms by which sponges establish symbiotic associations with members of the three domains of life, combining taxonomical, ecological, and molecular approaches. We study how sponges acquire their symbiotic microbes and whether these microbes contribute to shape the ecological distribution of their hosts. Moreover, we use the sponge-polychaete relationship as an example of multi-partner symbiosis and study the eukaryotic association from the microbial perspective. Finally, we focus on the less studied domain of life, the archaea, to gain insights into the composition and stability of these symbionts in sponges.
To assess these goals, we characterized the sponge assemblages in two contrasting environments (well-preserved and impacted) of Nha Trang Bay (Vietnam) and selected the most abundant species for the study of their microbiomes. Additionally, four sponge species harbouring thousands of polychaetes were sampled to analyse the relationships sponge-microbes-polychaetes. Sponges and polychaetes were identified and their respective microbiones and the seawater bacterial communities were analysed by high-throughput sequencing of the 16S rRNA gene (V4 region).
We first describe and illustrate the sponges collected to facilitate further taxonomic and faunistic studies in the area. Our samples belonged to 60 species (9 orders, 22 families, and 36 genera) of demosponges. A total of 24 species were added to the already known sponge fauna of Vietnam, from which, 11 species likely represent new species to science. The described species represent an increase of 8 % in the already known sponge list of Vietnam. Our results show that sponge assemblages were more diverse and rich in the well-preserved environments, being dominated by Neofibularia sp. and Aaptos suberitoides in the reefs, and by Monanchora unguiculata, Antho (Antho) sp., and Amphimedon sulcata in rocky habitats. On the other hand, impacted coral reefs were mainly dominated by two abundant species: Clathria reinwardti and Amphimedon paraviridis.
Similar ecological metrics were shown by the sponge microbiomes according to the type of habitat, being more diverse in the well-preserved environments. Morever, the sponge microbiomes of the sponge assemblages from the impacted habitats showed higher intra-species dispersion and lower core size (shared ZOTUs across species replicates) than microbiomes of sponges from the well-preserved environments. In this sense, we propose that the Anna Karenina concept, which states that intraspecific variability is higher in dysbiotic than in healthy individuals, can also be applied at the community level for the study sponge assemblages.
In our study sponges, bacterial communities were highly stable regardless of the environment, whereas some of their associated polychaetes varied depending on the sampling location. Environmental resilience to different habitat conditions was certainly true for bacterial communities of A. sulcata, the solely species that was found abundant in the two contrasting habitats explored.
Moreover, the high overlap in bacteria composition between sponges and seawater suggest microsymbiont acquisition from the environment. In a similar manner, polychaetes were also able to specifically select and enrich some bacteria from their food sponge. Overall, most sequences were shared between biotypes, but at differential abundances, leading to highly specific and stable invertebrate microbiomes, acquired from the environment. Our results support the tenet “Everything is everywhere, but the environment selects”.La vida en simbiosi representa una contribució fonamental a la diversitat dels ecosistemes marins. Les esponges són models ideals per l’estudi de les relacions simbiòtiques des del punt de vista evolutiu i ecològic, ja que són els metazous més antics de la Terra, són ubiqüistes al bentos marí, i estableixen simbiosis complexes amb procariotes i animals, que al seu torn, contenen les seves pròpies comunitats bacterianes. En aquesta tesis, volem aprofundir en els mecanismes pels quals les esponges estableixen associacions amb membres dels tres dominis de vida, combinant eines taxonòmiques, ecològiques i moleculars. Estudiem com les esponges adquireixen els seus microbis simbionts i com aquests microbis contribueixen a modelar la distribució ecològica de les esponges. A més, utilitzem la relació esponja-poliquet com a exemple de simbiosis multi-organisme i estudiem les associacions eucariotes des de un punt de vista microbià. Finalment, ens centrem en el domini de vida menys estudiat, les arqueas, per aprofundir en la composició i estabilitat d’aquests simbionts en esponges. Per assolir aquests objectius, vam caracteritzar els grups d’esponges de dos ambients diferenciats (impactat i ben preservat) de la badia de Nha Trang (Vietnam), i vam seleccionar les espècies més abundants per l’estudi del seu microbioma. Addicionalment, vam mostrejar quatre espècies d’esponges que contenien milers de poliquets per l’anàlisi de les relacions esponja-microbis-poliquets. Els nostres resultats mostren que les comunitats d’esponges eren més riques i diverses en els ambients ben preservats, i els seus microbiomes mostraven variables ecològiques similars, en els dos tipus d’ambients. La majoria de simbiosis estudiades mostraven una gran especificitat i estabilitat, independentment de l’ambient on vivia l’esponja. El gran solapament entre els bacteris de l’aigua i de l’esponja suggereix que hi ha adquisició microbiana de l’ambient. De forma similar, els poliquets també eren capaços d’adquirir específicament bacteris de les esponges de les quals s’alimentaven. En resum, la majoria de seqüències microbianes eren compartides entre els tres habitats estudiats (aigua/esponge/poliquet), però a diferents abundàncies, donant lloc a microbiomes específics i estables adquirits de l’ambient en els dos grups d’invertebrats estudiats .
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Rubio, Brent Kawika. "Bioactive natural products for global health from Papua New Guinea marine sponges /". Diss., Digital Dissertations Database. Restricted to UC campuses, 2008. http://uclibs.org/PID/11984.
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Khokhar, Shahan. "Chemical Investigations of Australian Marine Sponges Using Experimental and Theoretical NMR Spectroscopy". Thesis, Griffith University, 2015. http://hdl.handle.net/10072/367252.
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This thesis is divided into two parts (A and B). Our overall aim was to isolate and characterize natural products from Australian marine sponges. The uniqueness of this thesis arises from the application of Density Functional Theory (DFT), a quantum mechanical modelling method, which can be used to help elucidate and confirm molecular structures. DFT calculations, and in particular, DFT-NMR (Nuclear Magnetic Resonance) calculations, are still in their relative infancy. The research presented in Part A exemplifies DFT-NMR as a powerful technique, which can be added to a natural product chemist’s “structure-elucidation toolkit”.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Natural Sciences
Science, Environment, Engineering and Technology
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Habener, Leesa. "Investigating and comparing chemical and biological variation of marine sponges (phylum Porifera)". Thesis, Griffith University, 2018. http://hdl.handle.net/10072/382720.
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The work completed in this PhD thesis investigates and compares the chemical
and biological variation of marine sponges. A comprehensive literature review of
compounds isolated from the family Mycalidae was completed to characterise the known
chemical diversity of the family. In total 190 compounds were reported from 40 taxa
comprising a range of structure classes that include alkaloids, polyketides, terpene
endoperoxides, peptides, and lipids. The family is identified as a good target for
biodiscovery; macrocyclic polyketides display potent cytotoxicity (LC50 <1 μM), and
alkaloids (pyrrole derivatives) moderate cytotoxicity (LC50 1 – 20 μM). The pyrrole
alkaloids and cyclic peroxides are phylogenetically restricted to sponges and could
provide a good candidate for chemotaxonomic markers.
Morphological taxonomy of sponges is complicated by a lack of clear diagnostic
morphological characters, and chemical compounds are a useful set of characters that
can be explored. A 2D 1H-13C HSQC spectroscopic profiling technique was developed to
assess the chemical variation of sponge extracts. HSQC spectroscopic profiles (n=28)
comprising 6 species of three sponge families (Microcionidae, Mycalidae, and
Raspailiidae) showed consistent chemical profiles within family and over geographic
scales ranging from approximately 30 to 1700 km. Comparison of chemical shift values
to the literature resulted in the identification of chemical compounds that contain
chemical moieties indicated by the diagnostic H-C signals. LC-MS/MS enabled
identification of 22 known compounds, of which one, mycalamide A, was a sponge
natural product. HSQC spectroscopic profiling provides a powerful technique to
characterise the chemical moiety diversity that can be applied to both sponge taxonomy
and natural products discovery.
Molecular approaches have also been applied for the identification of sponge
species. Three mitochondrial markers (CO1, SP1, and SP2) were amplified for a
collection of sponges (n=144) from the Great Barrier Reef, Australia to group samples
into sets that share genetic similarity. This resulted in the establishment 34 molecular
operational taxonomic units (MOTUs) and 27 of these MOTUs were assigned order-level
identifications using phylogenetic reconstructions. Initially low amplification rates across
all three markers (ranging from 17.9 – 34.0 %) were improved after cleaning DNA
extracts with phenol-chloroform and reattempting amplification (increased to 60.4 – 75.5
%) for a subset of samples (n=106) indicating the presence of chemical inhibitors.
Integrative taxonomic approaches combining multiple datasets have been
proposed to assist sponge taxonomy. The developed HSQC spectroscopic profiling approach was applied to a subset (n=56) of the same samples collected from the Great
Barrier Reef. Analysis of spectroscopic profiles allowed the identification of three
chemical operational taxonomic units (ChOTUs) that displayed high chemical similarity.
Searching the literature resulted in the identification of chemical compounds that contain
chemical moieties indicated by the distinguishing H-C signals. The morphological
operational taxonomic units (OTUs) established at time of collection, and the MOTUs
and ChOTUs established here, were used to propose three putative taxa as a first step
in species delimitation.
Overall this thesis proposes a HSQC spectroscopic profiling method that can be
applied to sponge taxonomy as well as to natural products discovery efforts.
Spectroscopic profiles can be used to de-replicate samples and target samples
possessing unique chemical profiles. Through this process sponge families were shown
to display consistent spectroscopic profiles over large geographic scales; an important
finding for both sponge chemical taxonomy and biodiscovery projects. Additionally, this
thesis results in the proposal of three putative taxa on the basis of comparing chemical, morphological, and molecular variation.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Hanekom, Thea. "Screening bacterial symbionts of marine invertebrates for ribosomally synthesized natural products". University of the Western Cape, 2016. http://hdl.handle.net/11394/5441.
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>Magister Scientiae - MScPharmaceutical research and development strategies rely on the constant discovery of novel natural products as potential drugs. Recent studies have shown that the microorganisms associated with sponges are the true producers of some previously isolated compounds. This study created a large collection of bacterial symbionts associated with the South African marine sponge, Hamacantha esperioides. The bioactivity assays performed, showed that 44 isolates produced compounds with antimicrobial or anti-inflammatory activity. The successful identification of novel species that produce potential natural products highlights the importance of cultivation-dependent methods. To further screen for natural products, a cultivation-independent approach was used. A sequenced-based method, based on the biosynthetic genes of polytheonamide, was developed to screen for proteusins in sponge metagenomic DNA and the genomes of bacterial symbionts. The degenerate primers could amplify the targeted genes from DNA known to contain homologues. Evaluation of the primers' specificity showed non-specific amplification of genes, some containing similar conserved domains as the target genes. This study demonstrated that the use and development of cultivation-dependent and -independent screens are important for the discovery of novel natural products from the symbiotic bacteria of South African sponges.
National Research Foundation (NRF)
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Matobole, Relebohile Matthew. "Matrix comparison of isolation conditions for secondary metabolite producing marine sponge associated bacteria". University of the Western Cape, 2015. http://hdl.handle.net/11394/4754.
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>Magister Scientiae - MScThe discovery of novel secondary metabolites has declined significantly in recent years whereas there is a rise in the number of multi-drug resistant pathogens and other types of diseases. The decline in natural product discovery was due to high rediscovery of already known compounds and the costs in developing natural products. As a result pharmaceutical companies lost interest in investing in natural product discovery. However, there is a renewed interest in marine sponge associated microorganisms as a rich and untapped source of secondary metabolites. The objective of this study was to design a matrix to investigate the extent to which the One Strain-Many Compounds (OSMAC) approach applies to a collection of marine sponge isolates harvested from two South African marine sponge samples. Terminal restriction fragment length polymorphisms (T-RFLP) analysis was used to investigate and ascertain the two marine sponges which hosted the highest microbial diversities to be used for further culture-dependent studies. The culture-dependent studies, using 33 media which included liquid enrichment, heat treatments and antibiotic treatments, resulted in 400 sponge isolates from the two marine sponges Isodictya compressa and Higginsia bidentifera. Using antibacterial overlay assays, 31 dereplicated isolates showed antibacterial activity. Bioactivities were also exhibited against E. coli 1699 which is genetically engineered for resistance against 52 antibiotics which implies that some of the bioactive compounds could be novel. The 16S rRNA gene sequences revealed that the microbial phyla isolated from the marine sponges belonged to Actinobacteria, Firmicutes and Proteobacteria (Alphaproteobacteria and Gammaproteobacteria).Thirty isolates were selected for an OSMAC-based matrix study, 17 of which showed noantibacterial activities in preliminary screening. The application of the OSMAC approach using co-culture and 36 culture conditions resulted in 6 isolates showing antibacterial activities, three of which did not show activities in preliminary screening. One of these, a Bacillus pumilus isolated from I. compressa displayed antibacterial activity against 5 indicator strains whereas in preliminary screening it had not shown activity. The results show that marine sponges can host novel microbial species which may produce novel bioactive compounds. The results also confirm that traditional methods employing a single culture condition restricts the expression of some biosynthetic pathways of microorganisms and as a result many metabolites have yet to be identified.
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Crowe, Stacie E. "Abundance and Distribution of Commensal Amphipods From Common Marine Sponges of Southeast Florida". NSUWorks, 2001. http://nsuworks.nova.edu/occ_stuetd/306.
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Marine sponges were examined from shallow waters of southeast Florida and the Florida Keys to determine species composition and distribution of commensal amphipod crustaceans from shallow reef, mangrove, and seagrass habitats. Twenty sponge species were investigated during this study, sixteen of which housed amphipods in the families Colomastigidae and/or Leucothoidae. Six species of commensal amphipods were identified. Leucothoe spinicarpa (Abildgaard) species "complex" was the most dominant amphipod commensal, representing 63% of the total amphipods collected. The L. spinicarpa "complex" contains four local morphotypes, which are diagnosed and briefly described. Common sponge hosts included Callyspongia vaginalis, Mycale sp., and Myriastra kallitetilla.
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Daletos, Georgios [Verfasser]. "Isolation and Structure Elucidation of Bioactive Secondary Metabolites from Marine Sponges / Georgios Daletos". Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2016. http://d-nb.info/1101693908/34.
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Hatton, Christopher Martin. "Exploring marine sponges as a source of novel chemical entities for drug development". Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/74792/.
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Antibacterial resistant infections are one of the most challenging problems affecting healthcare and have developed through the overuse of antibiotics and a shortage of new treatments progressing to market. Natural products are the initial source of most antibiotics currently available and marine sponges are a known resource of novel antibacterial compounds; although well-‐studied marine sponges found in UK waters have been scarcely explored. An examination of the chemical research on sponges identified previously unstudied species for collection in both Greece and Wales. Sequential solvent gradient extraction was optimised, to best exploit the material collected, providing three crude extracts for each sponge collected. A significant difference was observed between the chemical composition of sponges collected from Greece and Wales. An efficient antimicrobial assay was developed to screen each extract against clinically relevant organisms; allowing the direct identification of activity on an eluted thin layer chromatography plate. This overlay data was used for detailed chemical analysis using high performance counter current chromatography, with some separated fractions displaying greater activity towards the bacterium methicillin resistant Staphylococcus aureus (MRSA) than vancomycin. The parent masses of compounds responsible for activity were identified by directly coupling the overlay assay data to mass spectrometry, identifying multiple novel parent masses. Dereplication of samples was completed using the database MarinLit and the construction of a molecular network to compare fragmentation patterns in mass spectra. Bacterial cultivation from Welsh sponge samples isolated 18 antibacterial strains, which were identified using 16S rRNA analysis. Four of these strains were previously uncultured. Chemical analysis was also completed, on two unstudied strains, identifying further active novel parent masses, with no parent mass crossover to the host sponge. Overall, this investigation concluded that marine sponges are excellent source of novel antibacterial compounds, which can display activity against clinically relevant bacteria equivalent to current treatments.
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Wegerski, Christopher John. "Chemistry under the sea : secondary metabolites from marine sponges of Papua New Guinea /". Diss., Digital Dissertations Database. Restricted to UC campuses, 2007. http://uclibs.org/PID/11984.
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Mohamed, Naglaa M. "Ecophysiology of microbial communities associated with marine sponges (Ircinia strobilina) and (Mycale laxissima)". College Park, Md.: University of Maryland, 2007. http://hdl.handle.net/1903/7722.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2007.Thesis research directed by: Marine, Estuarine, Environmental Sciences Graduate Program. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Spring, David R. "Studies on the biomimetic synthesis of the manzamine alkaloids". Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268166.
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Watson, Daniel John. "Studies directed towards the total asymmetric synthesis of Altohyrtin A". Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364263.
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Cebrian, Pujol Emma. "Sublethal effects of heavy metal contamination on marine sponges: Responses at different biological levels". Doctoral thesis, Universitat de Barcelona, 2007. http://hdl.handle.net/10803/805.
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Many antrophic activities release pollutants to the marine environment. Among them heavy metals are of great importance, since they are conservative pollutants, which can be accumulated through trophy chains. Sometimes, the liberation to the marine waters is acute and drastic, leading to massive mortalities. However, more often, the liberation is by means of low and chronic concentrations. The main objective of the present thesis is to analyze the sponge responses in face to sublethal concentrations of heavy metals and to determine, if it is possible, whether they can be used as biomonitors of such kind of pollution. First, we have studied their availability to accumulate havey metals in both, temporal and especial scales. And then, by means of the use of different biomarkers, to analyze the sublethal effects of heavy metals on sponges at different levels of biological organization, from molecules to populations. The present thesis has been performed by means of experiments in situ and at the laboratory, in order to elucidate heavy metal accumulation patterns and their effects depending on the specie and metal considered.TÍTOL DE LA TESI: "Efectes subletals de la contaminació per metalls pesats en esponges marines: Respostes a diferents nivells d'organització".
TEXT:
Moltes activitats antròpiques alliberen contaminants en el medi. Entre els contaminants hem de destacar els metalls pesants, ja que són contaminants conservatius y que s'acumulen a través de les xarxes tròfiques. En alguns casos la alliberació dels contaminants en el medi es dona de forma aguda i dràstica, el què pot provovar mortalitats massives. De totes formes, de forma general l'alliberació al medi dels metalls pesants es dóna a baixes concentracions i de forma crónica. L'objectiu principal d'aquesta tesis és analitzar les respostes de les esponges a concentracions subletals de metalls pesants i determinar la seva utilitat com a biomonitors d'aquest tipus de contaminació. En primer lloc, s'ha d'estudiar la capacitat de les esponges per acumular metalls pesants tant a una escala temporal com espaial. En segon lloc, mitjançant l'ús de diferents biomarcadors, analitzar els efectes subletals dels metalls en les esponges, a diferents nivells d'organització biológica, desde les molècules fins a les poblacions. Aquesta tesis s'ha dut a terme mitjançant experiments que convinen aproximacions in situ i en el laboratori per tal de compendre de millor maners els models d'acumulació i els seus efectes en funció de l'espècie i el metall considerat.
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Callahan, Michael K. "Distribution of clionid sponges in the Florida Keys National Marine Sanctuary (FKNMS), 2001-2003". [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001017.
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Swasono, Respati Tri. "Bioactive secondary metabolites from Australian invertebrates, Indonesian marine sponges, and an Indonesian terrestrial plant /". [St. Lucia, Qld.], 2006. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19275.pdf.
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Abualreesh, Heba. "Screening for antibacterial metabolites in marine sponges collected from the coastline of Sri Lanka". Thesis, Uppsala universitet, Farmakognosi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-451690.
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Natural products and their derivatives have and are still used by humans for various health ailments due to their rich sources of drug discovery. New biologically active compounds from natural products play a key role in drug development. Marine sponges and their associated microbes contain a lot of bioactive compounds that are potential for drug development. These compounds produce chemical compounds with useful pharmaceutical properties such as antitumor, anti-infective, anti-inflammatory, and antibacterial properties. The main focus of this project was on the antibacterial activity of six different sponge specimens. The aim was to screen the antibacterial activity of the sponge specimen’s extracts. In order to do so, a Minimum Inhibitory Concentration assay was performed to screen the sponge's antibacterial activity against E. coli and S. aureus. Analytical HPLC was used for separation and Solid Phase Extraction (SPE) was used for determining the effect of salts towards the inhibition of anti-bacterial activity for two selected extracts. Ethanolic extract of Stylissa massa showed antibacterial activity against S. aureus. SPE would be a rapid purification step to remove the salts present in sponges at a high concentration but it has not shown a significant effect on the inhibition of antibacterial activity. However, further separation and purification need to be done to be able to completely screen for all the six different sponge specimens.
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MAZZELLA, VALERIO. "Microbiome, metabolic and phenotypic traits in the adaptability of marine sponges to Ocean Acidification". Doctoral thesis, Università Politecnica delle Marche, 2021. http://hdl.handle.net/11566/291001.
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Il progressivo incremento delle emissioni di CO2 in atmosfera dovuto alle attività antropiche ed il conseguente assorbimento da parte degli oceani stanno determinando importanti modificazioni del sistema carbonatico e una diminuzione del pH nei mari a livello globale. Questo fenomeno, noto come acidificazione oceanica, è atteso determinare nei prossimi decenni profonde modificazioni della biodiversità e nel funzionamento degli ecosistemi marini. In particolare, ci si aspetta un forte declino degli organismi calcificanti, mentre organismi non calcificanti, o fototrofi potrebbero essere favoriti. Le spugne sono tra i metazoi bentonici più antichi, sono presenti a tutte le latitudini e svolgono importanti funzioni ecologiche. Tali organismi sono noti contrarre relazioni di simbiosi con numerosi taxa microbici e produrre numerosi metaboliti con diverse funzioni ecologiche. Tuttavia, si conosce ancora poco sugli effetti dell’acidificazione sull’olobionte e sui potenziali meccanismi di acclimatazione e adattamento in risposta all’attesa diminuzione di pH per la fine del secolo. Questo studio ha analizzato, attraverso un approccio multidisciplinare, l'effetto dell'acidificazione oceanica su abbondanza, tratti morfologici, microbioma e metaboloma di Poriferi lungo un gradiente naturale di pH nei pressi dell'isola di Ischia. Sono state studiate quattro specie di spugne, Petrosia ficiformis, Chondrosia reniformis, Crambe crambe e Chondrilla nucula, selezionate in quanto presenti anche in molte altre aree del Mare Mediterraneo, le quali sono state campionate sia in siti acidificati sia in siti di controllo adiacenti. I risultati di questo studio indicano la mancanza di evidenti modificazioni anatomiche-strutturali degli individui che vivono nei siti acidificati rispetto a quelli di controllo. L’analisi del microbioma associato alle spugne evidenzia variazioni specie dipendenti, con cambiamenti in relazione alle condizioni di pH specie-specifici. In particolare, le spugne P. ficiformis e C. crambe mostrano marcati cambiamenti di biodiversità del microbioma associato in relazione all’acidificazione, mentre C. reniformis e C. nucula mostrano microbiomi maggiormente simili tra siti acidificati e di controllo. Anche l’analisi metabolomica condotta su P. ficiformis e C. crambe evidenzia differenze specie dipendenti (i.e. numero di metaboliti in comune molto esiguo) e risposte all’acidificazione specie-specifiche. A tale proposito, il profilo metabolomico della spugna C. crambe è simile tra individui campionati in condizioni di acidificazione e di controllo, mentre quello di P. ficiformis mostra importati differenze in relazione ai valori di pH. Questi risultati, nel loro insieme, suggeriscono processi di acclimatazione dell’olobionte alle condizioni di acidificazione specie-specifici, e come tali da tenere in debita considerazione per una valutazione delle potenziali conseguenze dell’acidificazione oceanica sulla biodiversità e funzioni ecologiche delle spugne. In generale, i risultati di questo studio evidenziano una elevata tolleranza e plasticità delle spugne silicee a condizioni di acidificazione, suggerendo una loro elevata capacità ad adattarsi ad una diminuzione di pH di ca. 0.3-0.4 unità attesa per la fine del secolo.The progressive increase of CO2 emissions into the atmosphere due to anthropogenic activities and the consequent absorption by the oceans are causing important changes in the carbonate chemistry of the seawater and a lowering of its pH. This phenomenon, known as Ocean Acidification, is expected to lead to profound changes in the biodiversity and functioning of marine ecosystems in the next decades. In this context, calcifying organisms are predicted to be severely threatened, while non-calcifying or photosynthetic organisms are forecasted as “winners” in future acidified scenarios. Among non-calcifying organisms, marine sponges can be one of the “winners”. They belong to the phylum Porifera, which is widespread in the marine environments, and are characterized by simple anatomical structures and constitutes one of the oldest sessile taxa. These organisms are of paramount relevance in benthic communities for their capability to recycle nutrients, for their rich associated microbiomes, representing model holobiont systems, and for their metabolic versatility and secondary metabolite production. In this dissertation four Mediterranean sponge species (i.e. Petrosia ficiformis, Chondrosia reniformis, Crambe crambe and Chondrilla nucula) have been selected to conduct an in situ investigation to evaluate adaptation traits to ocean acidification. The experimental work took place along the volcanic CO2 vents off Ischia island, which mimic the lowered pH conditions predicted for the end of this century. The aims of this study included: the investigation of sponges’ distribution across acidified and control sites, and the assessment of acclimatization responses in the morphology, associated microbiomes and metabolomic profiles. The outcomes of this thesis highlight species-specific responses. In general, no morphological traits were found to change in acidified versus control conditions. P. ficiformis and C. crambe revealed changes in their associated microbiomes across the pH gradient, while C. reniformis and C. nucula showed more stable microbiomes. Metabolomics signatures, investigated in P. ficiformis and C. crambe, revealed differences both in primary and secondary metabolites between specimens of P. ficiformis inhabiting acidified and control sites, while slight differences only in primary metabolites were observed for C. crambe across sites. Marine sponges seem to be generally tolerant to ocean acidification, and capable to thrive in extreme conditions. This is the first study investigating the microbiome and metabolome of marine sponges under OA with an in situ approach.
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Hassanzada, Caidra Elizabeth. "Biodiversity and Ecological Dynamics of Sciophilous Benthic Communities on Artificial Plates: Emphasis on Reef Sponges". NSUWorks, 2015. http://nsuworks.nova.edu/occ_stuetd/390.
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Low light intensity habitats harbor unique sciophilous benthic communities and are a source of novel and unique sponge fauna. However, the community structure of these habitats is poorly studied to date. Thus, this study attempts to understand the composition and structure of sciophilous sponge populations in southeast Florida. Fifty limestone plates were placed on a shallow reef in Fort Lauderdale for two years (2010-2012). To identify the sponge community and their patterns over time, all plates were photographed at the end of each year. Then, samples were taken from each of the live sponge specimens observed on the plates and processed in the laboratory for taxonomical identification. A total of 45 different sponge species were found, the majority corresponding to the Poecilosclerida Order. Eighteen were identified to species level, twenty-two to genus, and five were undetermined. Eight sponges constitute new records to Florida, and four are potentially new species. The most dominant species include Oscarella sp.1, Dysidea etheria, Mycale sp.1, Halisarca caerula and Tedania ignis. Species richness significant varied among years, and species cover among sectors (inner and outer reef). However, sponge assemblages were similar between years with slightly variation between sectors. This study found a diverse and complex composition and structure of sponges that is quite distinct from the sponge assemblages on the open reefs. A guide of the biodiversity of cryptic sponge species was created to facilitate further studies in low light intensity habitats.
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Lira, Simone Possedente de. "\"Metabólitos secundários biologicamente ativos isolados de esponjas marinhas e do fungo Beauveria felina de origem marinha\"". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-05062007-112443/.
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Neste trabalho descreve-se o estudo química dos extratos de quatro esponjas e dois fungos de origem marinha oriundos da costa do Brasil. Os extratos de três esponjas (Petromica ciocalyptoides, Topsentia ophiraphidites e Callyspongia sp.) apresentaram atividade inibitória à enzima adenosina fosforribosil transferase de Leishmania tarentolae. A partir desses extratos foram isolados 4 compostos. O trissulafato de halistanol, isolado das esponjas P. ciocalyptoides e T. ophiraphidites, e o ilhabelanol, ilhabreno e isoakaterpina, isolados da esponja Callyspongia sp. A partir do extrato bruto da esponja Axinella cf corrugata foram isolados dois derivados cumarínicos, provavelmente artefatos de isolamento do ácido 4-esculetínico, o qual é inédito como produto natural. O extrato bruto da esponja Axinella cf. corrugata apresentou atividade citotóxica, mas os compostos puros não apresentaram esta atividade. Os dois compostos puros foram testados ainda quanto sua atividade contra o vírus da SARS, na qual o éster etílico do ácido 4-esculetínico se apresentou ativo. A partir de dois extratos oriundos do fungo Beauveria felina, isolado da alga marinha Caulerpa sp, foram isoladas 17 frações puras que após diversas análises foram agrupadas em seis compostos conhecidos na literatura: a (Phe3, N-Val5) destruxina B, a cloroidrina da destruxina E, a roseotoxina B, a roseocardina, a isariina e a isariina B. Além disso, foram isolados dois compostos inéditos, a pseudodestruxina C e a cloloidrina Beta-Me-Pro da destruxina E. Os extratos brutos de Beauveria felina apresentaram atividades em bioensaios de atividade antituberculose e de citotoxicidade em linhagem de células de câncer. Os compostos puros avaliados no bioensaio antituberculose não foram ativos. Somente o composto roseotoxina B apresentou atividade citotóxica in vitro para quatro linhagens de células: mama, cólon, sistema nervoso e leucemia.In this work we report the chemical investigation of bioactive crude extracts obtained from four sponges and two fungal strains of marine origin. The crude extracts of three sponges species (Petromica ciocalyptoides, Topsentia ophiraphidites and Callyspongia sp.) displayed inhibitory activity towards the enzyme adenine fosforribosyl transferase of Leishmania tarentolae (L-APRT). Four compounds have been isolated from these extracts: the known halistanol sulfate was isolated of sponges P. ciocalyptoides and T. ophiraphidites, while the novel ilhabelanol, ilhabrene and isoakaterpin have been isolated from the sponge Callyspongia sp. All compounds exhibited inhibition of L-APRT at micro M concentrations. Two coumarin derivatives have been isolated from the crude extract of the sponge Axinella cf. corrugata, probably as artifacts of isolation: esculetin-4-carboxylic acid methyl ester and esculetin-4-carboxylic acid ethyl ester. While the crude extract of the sponge Axinella cf. corrugata presented cytotoxic activity, the pure compounds were inactive in these assays. The esculetin-4-carboxylic acid ethyl ester was found to be an in vitro inhibitor of SARS virus. The crude extract obtained of a marine-derived Beauveria felina strain, isolated from the alga Caulerpa sp., displayed antituberculosis activity against Mycobacterium tuberculosis H37Rv and cytotoxic activity against MCF-7 (breast), HCT-8 (colon) and B16 (murine melanoma) cancer cell lines. Chemical fractionation of the crude extract led to the isolation of two new cyclodepsipeptides pseudodestruxin C and [Beta-Me-Pro] destruxin E chlorohydrin, and of the known destruxin E chlorohydrin, [Phe3, N-Me-Val5] destruxin B, roseotoxin B, roseocardin, isariin and isariin B. The depsipeptides [Phe3, NMe- Val5] destruxin B and rosetoxin B, have been tested against M. tuberculosis H37 Rv and in cytotoxicity bioassays against SF 295 (human CNS) MDA-MB435 (human breast) HCT8 (colon) and HL60 (leukemia) cancer cell lines. Only roseotoxin B displayed moderate cytotoxicity against the cancer cell lines.
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Hedner, Erik. "Bioactive Compounds in the Chemical Defence of Marine Sponges : Structure-Activity Relationships and Pharmacological Targets". Doctoral thesis, Uppsala University, Division of Pharmacognosy, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8218.
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Marine invertebrates, in particular sponges, represent a source of a wide range of secondary metabolites, many of which have been attributed various defensive capabilities against environmental stress factors. In this thesis sponge-derived low-molecular peptide-like compounds and associated analogs are investigated for bioactivity and pharmacological targets.
The compound bromobenzisoxazolone barettin (cyclo[(6-bromo-8-(6-bromo-benzioxazol -3(1H)-one)-8-hydroxy)tryptophan)]arginine) was isolated from the sponge Geodia barretti and its ability to inhibit larval settlement of the barnacle Balanus improvisus was determined. With an EC50 value of 15 nM, this compound’s antifouling effect was higher than those of the previously reported brominated dipeptides from Geodia barretti, i.e., barettin and 8,9-dihydrobarettin; moreover, this antifouling effect was demonstrated to be reversible. However, the compound lacked affinity for 5-HT1-7 receptors, whereas barettin possessed specific affinity to 5-HT2A, 5-HT2C and 5-HT4, while 8,9-dihydrobarettin interacted with 5-HT4. In an attempt to evaluate structure-activity relationships synthesized analogs with barettin and dipodazine scaffolds were investigated for antifouling activity. The analog benso[g]dipodazine, with an EC50 value of 34 nM, displayed the highest settlement inhibition.
The studies of the structure-activity relationships of sponge-derived compounds were extended to cover analogs of agelasines and agelasimines originally isolated from sponges of the genus Agelas. Synthesized (+)-agelasine D and two structurally close analogs were investigated for cytotoxic and antibacterial activity. The profound cytotoxicity and broad spectrum antibacterial activity found prompted a further investigation of structure-activity relationships in 42 agelasine and agelasimine analogs and several characteristics that increased bioactivity were identified.
In conclusion this work has produced new results regarding the potent bioactivity of compounds derived from the sponges Geodia barretti and Agelas spp. and increased SAR knowledge of the fouling inhibition, cytotoxicity and antimicrobial activity of these compounds.
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Höller, Ulrich. "Isolation, biological activity and secondary metabolite investigations of marine-derived fungi and selected host sponges". [S.l.] : [s.n.], 1999. http://www.gbv.de/dms/bs/toc/271061243.pdf.
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Pimentel, Elardo Sheila Marie. "Novel anti-infective secondary metabolites and biosynthetic gene clusters from actinomycetes associated with marine sponges". Doctoral thesis, kostenfrei, 2008. https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-40463.
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Marine sponges (Porifera) harbor diverse microbial communities within their mesohyl, among them representatives of the phylum Actinobacteria, commonly known as actinomycetes. Actinomycetes are prolific producers of pharmacologically important compounds and are responsible for producing the majority of antibiotics. The main aim of this Ph.D. study was to investigate the metabolic potential of the sponge-associated actinomycetes to produce novel anti-infective agents. The first aim was to cultivate actinomycetes derived from different marine sponges. 16S rDNA sequencing revealed that the strains belonged to diverse actinomycete genera such as Gordonia, Isoptericola, Micromonospora, Nocardiopsis, Saccharopolyspora and Streptomyces. Phylogenetic analyses and polyphasic characterization further revealed that two of these strains represent new species, namely Saccharopolyspora cebuensis strain SPE 10-1T (Pimentel-Elardo et al. 2008a) and Streptomyces axinellae strain Pol001T (Pimentel-Elardo et al. 2008b). Furthermore, secondary metabolite production of the actinomycete strains was investigated. The metabolites were isolated using a bioassay-guided purification scheme followed by structure elucidation using spectroscopic methods and subjected to an elaborate anti-infective screening panel. Several interesting compounds were isolated namely, the novel polyketides cebulactam A1 and A2 (Pimentel-Elardo et al. 2008c), a family of tetromycin compounds including novel derivatives, cyclodepsipeptide valinomycin, indolocarbazole staurosporine, diketopiperazine cycloisoleucylprolyl and butenolide. These compounds exhibited significant anti-parasitic as well as protease inhibitory activities. The third aim of this Ph.D. study was to identify biosynthetic gene clusters encoding for nonribosomal peptide synthetases (NRPS) and polyketide synthases (PKS) present in the actinomycete strains. Genomic library construction and sequencing revealed insights into the metabolic potential and biosynthetic pathways of selected strains. An interesting NRPS system detected in Streptomyces sp. strain Aer003 was found to be widely distributed in several sponge species, in an ascidian and in seawater and is postulated to encode for a large peptide molecule. Sequencing of the PKS gene cluster of Saccharopolyspora cebuensis strain SPE 10-1T allowed the prediction of the cebulactam biosynthetic pathway which utilizes 3-amino-5-hydroxybenzoic acid as the starter unit followed by successive condensation steps involving methylmalonyl extender units and auxiliary domains responsible for the polyketide assembly. In conclusion, this Ph.D. study has shown that diverse actinomycete genera are associated with marine sponges. The strains, two of them novel species, produced diverse chemical structures with interesting anti-infective properties. Lastly, the presence of biosynthetic gene clusters identified in this study substantiates the biosynthetic potential of actinomycetes to produce exploitable natural products and hopefully provides a sustainable supply of anti-infective compoundsZahlreiche marine Schwämme (Phylum: Porifera) beherbergen eine phylogenetisch diverse mikrobielle Gemeinschaft in der Mesohyl-Matrix, darunter auch viele Vertreter des bakteriellen Phylums Actinobacteria, die umgangssprachlich als Actinomyceten bekannt sind. Actinomyceten sind wichtige Produzenten vieler Antibiotika und von weiteren pharmazeutisch relevanten Substanzen. Das Hauptziel dieser Promotionsarbeit war die Untersuchung des Potentials Schwamm-assoziierter Actinomyceten zur Produktion neuer Infektions-hemmender Substanzen. Ein erstes Ziel dieser Doktorarbeit war die Kultivierung von Actinomyceten aus verschiedenen marinen Schwammarten. Die Sequenzierung der respektiven 16S rRNA Gene zeigte eine phylogenetische Zugehörigkeit der Isolate zu verschiedenen Actinomyceten-Familien, wie Gordonia, Isoptericola, Micromonospora, Nocardiopsis, Saccharopolyspora und Streptomyces. Durch phylogenetische Analysen und umfangreiche taxonomische Charakterisierungen konnten zwei neue Actinomyceten-Arten, Saccharopolyspora cebuensis strain SPE 10-1T (Pimentel-Elardo et al. 2008a) und Streptomyces axinellae strain Pol001T (Pimentel-Elardo et al. 2008b) beschrieben werden. Des Weiteren sollten die Actinomyceten-Isolate auf die Produktion von Sekundär-Metaboliten hin untersucht werden. Die Substanzen wurden „bioassay-guided“ aufgereinigt und isoliert sowie deren Struktur mittels spektroskopischer Methoden aufgeklärt. Anschließend wurden die Substanzen ausführlichen Screening-Methoden unterzogen, um sie auf anti-infektive Wirkungen hin zu untersuchen. Zahlreiche interessante Verbindungen konnten so isoliert werden, u. a. die neuen Polyketide Cebulactam A1 und A2 (Pimentel-Elardo et al. 2008c); eine Familie von Tetromycin-Substanzen inklusive neuartiger Derivative; das Cyclodepsipeptid Valinomycin, Indolocarbazole Staurosporine, Diketopiperazine Cycloisoleucylprolyl und Butenolide. Die Verbindungen zeigten signifikante anti-parasitische und Protease-hemmende Aktivitäten. Das dritte Ziel dieser Arbeit war es, die für nicht-ribosomale Peptidsynthetasen (NRPS) und Polyketidsynthasen (PKS) kodierenden, biosynthetischen Gen-Cluster in den Actinomyceten-Isolaten zu identifizieren. Die Konstruktion von Genbanken sowie die Sequenzierung ausgewählter Cosmidklone lieferte erste Einblicke in das Stoffwechsel- und Biosynthesepotential ausgewählter Isolate. Beispielsweise konnte ein interessantes NRPS-System in Streptomyces sp. Stamm Aer003 identifiziert werden, welches in verschiedenen Schwammarten, einer Ascidienart sowie im Meerwasser gefunden wurde. Die Sequenzierung eines PKS-Genclusters aus Saccharopolyspora cebuensis strain SPE 10-1T ermöglicht die Voraussage des Cebulactam-Biosynthesewegs in dem 3-Amino-5-Hydroxybenzoesäure als Ausgangsprodukt dient, welches durch sukzessive Kondensationsschritte sowie Verlängerungen durch Methylmalonyl- und Zusatzdomänen zum endgültigen Polyketid führen. Zusammenfassend konnte in dieser Promotionsarbeit gezeigt werden, dass marine Schwämme mit diversen Vertretern aus verschiedenen Familien der Actinomyceten assoziiert sind. Die Bakterienisolate, von denen zwei neue Arten repräsentieren, produzierten mehrere chemische Substanzen mit interessanten anti-infektiven Eigenschaften. Des Weiteren konnte mit dieser Arbeit durch die Identifizierung von Biosynthese-Genclustern das Potential von Actinomyceten zur Produktion verwertbarer bioaktiver Substanzen bekräftigt und somit ein Beitrag zur Entdeckung neuer anti-infektiver Substanzen erbracht werden
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Tucker, David John, i n/a. "An Investigation of the Chemical Constituents of Two Species of Marine Sponge". Griffith University. Division of Science and Technology, 1990. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050826.155059.
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An investigation of the dichioromethane extract of the sponge, Xestospongia testudinaria indicated that the extract was composed of approximately 40% sterols, 30% saturated fatty acids, 10% mono-unsaturated fatty acids and 20% poly-unsaturated acids. The sterol profile was found to vary between two collections of the sponge. In the first collection the major sterol was the C30 compound, xestosterol (4), which had not previously been reported to occur in this species. In the second collection there was a wider distribution of components with cholesterol (2a) being a major constituent and xestosterol being present in a much lower percentage than in the first collection. The poly-unsaturated acid fraction contained an extremely complex mixture. The novel brominated bisacetylenic C18 (47) and brominated C28 (65) acids were found to be the major components. Another six novel brominated acetylenic acids, which were very unstable, were also identified as well as an ester of 4 with 47. The method developed for the separation of the poly-unsaturated acids from the other classes of metabolites and for the isolation of the pure compounds is discussed and their structural elucidation, largely on the basis of NIMR spectroscopy is described. From the hexane extract of Carteriospongia foliascens, two novel bisalkylated norscalarane derivatives (114 and 116) and a bisalkylated scalarane derivative (130) have been isolated. By use of high field NMR and multipulse NMR techniques a complete assignment of the 111 and 13C NMR spectra of 130 has been achieved on 1.5mg of material. This represents the first report of a complete assignment of the 1J4 NMR spectrum of a scalarane derivative. The C-4 stereochemistry of 130 was determined by use of 1H NMR spectroscopic techniques, which gave results in agreement with the previously used 13C NMR method.
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Tucker, David John. "An Investigation of the Chemical Constituents of Two Species of Marine Sponge". Thesis, Griffith University, 1990. http://hdl.handle.net/10072/367459.
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An investigation of the dichioromethane extract of the sponge, Xestospongia testudinaria indicated that the extract was composed of approximately 40% sterols, 30% saturated fatty acids, 10% mono-unsaturated fatty acids and 20% poly-unsaturated acids. The sterol profile was found to vary between two collections of the sponge. In the first collection the major sterol was the C30 compound, xestosterol (4), which had not previously been reported to occur in this species. In the second collection there was a wider distribution of components with cholesterol (2a) being a major constituent and xestosterol being present in a much lower percentage than in the first collection. The poly-unsaturated acid fraction contained an extremely complex mixture. The novel brominated bisacetylenic C18 (47) and brominated C28 (65) acids were found to be the major components. Another six novel brominated acetylenic acids, which were very unstable, were also identified as well as an ester of 4 with 47. The method developed for the separation of the poly-unsaturated acids from the other classes of metabolites and for the isolation of the pure compounds is discussed and their structural elucidation, largely on the basis of NIMR spectroscopy is described. From the hexane extract of Carteriospongia foliascens, two novel bisalkylated norscalarane derivatives (114 and 116) and a bisalkylated scalarane derivative (130) have been isolated. By use of high field NMR and multipulse NMR techniques a complete assignment of the 111 and 13C NMR spectra of 130 has been achieved on 1.5mg of material. This represents the first report of a complete assignment of the 1J4 NMR spectrum of a scalarane derivative. The C-4 stereochemistry of 130 was determined by use of 1H NMR spectroscopic techniques, which gave results in agreement with the previously used 13C NMR method.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Division of Science and Technology
Full Text
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Knestrick, Matthew A. "From Florida to Antarctica: Dereplication Strategies and Chemical Investigations of Marine Organisms". Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7635.
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In the fight against disease and illness, nature has provided mankind some of our best therapeutics in the form of secondary metabolites. The plant, fungi and animal phyla inhabiting the Earth produce diverse and unique chemistry that can be used in our fight against disease. In the growing threat of drug resistance and pathogen evolution, the field of natural products chemistry strives to explore new biological and chemical diversity sources, and develop innovative methodology to identify and isolate new chemistry faster than ever.
The dissertation herein presented is one such effort to find new, bioactive chemistry from the marine environments. New biodiversity sources, from the tropical Floridian mangrove forests to the cold waters of the Antarctic oceans, were evaluated for the new, unique chemistry they produce. A large-scale screening of epigenetically modulated mangrove fungi was undertaken, producing a large, biologically and chemically diverse extract library. New methodology was developed in order to evaluate these extracts, leading to rapid identification and isolation of known and new bioactive metabolites. From the Southern Oceans, a collection of sponges was studied, and a new, highly unique peptide was isolated and characterized. These efforts were undertaken in the continued effort to isolate new, unique lead compounds.
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Ismail, Noraznawati. "Interactions between sponges and marine bacteria as a route to the discovery of novel bioactive compounds". Thesis, Heriot-Watt University, 2006. http://hdl.handle.net/10399/2076.
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The bacterial community architecture associated with four species of sponges, Halichondria panicea, Suberites domuncula, S. carnosus and Pachymatismajohnstonia 'was investigated using culture-dependent and culture-independent strategies. Marine '/ agar was found to be the best of several media used for cultivation of culturable bacteria : associated with sponges. Molecular methods, including denaturing gradient gel ,electrophoresis (DGGE), 16S rDNA cloning and sequence analysis suggested a : bacterial community different from that identified using culture-dependent methods. DGGE can provide a profile of the whole community of the sponge and facilitate screening of large-scale samples. 90% ofthe bacteria associated with these four sponges were sponge species-specific. S. carnosus was also transferred to an aquarium to study kinetic changes of sponge-associ~tedbacterial communities. DGGE analysis showed 'the consistent presence of some particular bands suggesting the continued presence of species of symbiotic bacteria. Four Bacillus species (B. licheniformis SC-43, B. subtilis SD-8, B. pumilus HP-48 and B. cereus HP-22) isolated from the sponges exhibited antagonistic activity against isolates of Gram-positive bacteria obtained from the same .sponges. All strains tested were active against Micrococcus luteus, strain HP-5!6 isolated from H. panicea. This suggests that HP-5!6 can be used in the laboratory as a sensitive indicator of activity. A comparison of several media found Nutrient Agar! Broth containing glycerol and iron (NGF) to be the best medium tested for antimicrobial , compound production. B. licheniformis (SC-43), B. subtilis (SD-8), and Pantoea sp., SC-AF, in the presence of glycerol and ferric ion, could produce antimicrobial '. compounds when grown within ,biofilms; however, the corresponding shaken flask cultures could not. This effect could be related to oxidative stress defence responses. Pantoea sp., SC-AF produced several antimicrobial compounds active against M luteus, HP-5!6 which were different from previously reported Pantocin antimicrobials. In addition, Pantoea sp., SC-AF produced 'jelly-like' extracellular polysaccharide (EPS) ' on NGF and on the nylon membrane in Air-membrane surface bioreactor (AMS) cultures, along with the production of antimicrobial compounds. Only fructose and cellobiose after acid lysis of EPS of Pantoea sp., SC-AF have been identified. In addition, my study confirmed that sponges accommodate large amounts of uncultured bacteria, whose metabolic capability cannot be explored without cultivation. New cultivation strategies should be investigated and biofilm-based culture techniques incorporated in the future search for novel antibiotics.
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McQuillan, Lea. "Species richness, density and cover of sponge assemblages on temperate reefs off Perth, Western Australia". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2006. https://ro.ecu.edu.au/theses/359.
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Sponges were the dominant faunal benthic group, occupying 30 -50% of the limestone reef surface and displaying high diversity (>240 sponge species) on subtidal temperate reefs off Perth, Western Australia. Despite this high diversity there was little variation in composition among the six different sites sampled. However, there was within-site heterogeneity of sponge assemblages which has been ascribed to small-scale variation in light and sedimentation/abrasion rates. Differences in sponge assemblages were also detected between sampling times, species richness and sponge density were higher in winter compared to summer, whereas, sponge cover was higher in summer compared to winter. The results suggest that the growth and development of juveniles or annuals may have been adversely affected by the harsh conditions of winter. The higher temperatures in summer appeared to promote growth and reproduction of sponges.
Rapid assessment techniques have been proposed to look for patterns in biodiversity in conservation biology studies, when detailed routine surveys are not feasible. Two rapid assessment techniques were assessed, firstly examining the dominant sponge species; and secondly aggregating the sponge species to order level. The results of two rapid assessment techniques were promising if comparing sponge assemblages across habitats. If the aim was to assess sponge assemblages across sites, neither rapid assessment technique showed the same results compared to species level data. The general conclusion for subtidal temperate reef sponge assemblages within Marmion Lagoon is that there is substantial loss of information for spatial comparisons when aggregating species to order level or using only the dominant sponges. What was found was that the two levels failed to detect differences among sites which were found in the species level data analyses, but all three analyses gave the same results for habitat data.
In Western Australia only a few studies on sponges have been undertaken along the extensive coastline (12,500 km long). Previous sponge research in Western Australia occurred predominately as a result of taxonomic collections from expeditions undertaken in the 19th and early 201 h centuries. This study has described the 43 dominant sponge species that were found at six different sites on subtidal temperate reefs in Marmion Lagoon, Western Australia. Sponges were the dominant fauna found at most of the research sites off this coastal Perth location and included many species from a range of orders and families. Most of the species found occurred in sciaphilic (shade-loving) habitats. Only a few species occurred in full light conditions on the reef flats.
This study documented 243 sponge species from subtidal limestone reefs between 8-12 metres in depth within the Lagoon. These 243 species comprised 197 siliceous sponges (Class Demospongiae) and 46 calcareous sponges (Class Calcarea) and were identified to at least order. Eighteen were identified to order, 88 to family, 35 to genus and 56 to species level. Approximately 30% of the species recorded here are possibly new to science.