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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Bycatch and Discarding under Species Interactions

Chen, Hsi-wen 25 June 2010 (has links)
By-catch is an unavoidable problem in fishery, and the occurrence of by-catch may lead to the phenomenon of discarding. Discarding of non-targeted species will not only result in the losses in economic, but may also damage the resource stock. As the interaction between species exists, the economic costs and the degree of damage derive from by-catch and discarding will become increasingly complicated. The research will start from the assumption of possible interactions between species, investigating that under different interactions between species, the possible influence to the optimal decision of fishermen and resource stocks.
2

Evaluation of fisheries by-catch and by-product meals in diets for red drum (Sciaenops ocellatus)

Whiteman, Kasey 12 April 2006 (has links)
By-catch and wastes from processed fish and shrimp constitute a sizeable portion of commercial fishery landings. This discarded material is potentially valuable, for its content of fish meals and other substances. Fish meals, in particular, are increasingly in short supply for the manufacture of animal feeds, including feeds for farmed fish. Therefore, in this study, various by-catch and by-product meals of marine origin were evaluated with red drum (Sciaenops ocellatus), a carnivorous fish species native to the Gulf of Mexico that has been cultured over the past two decades for stock enhancement as well as for food. Four different kinds of by-catch or by-product meals [shrimp by-catch meal, shrimp processing waste meal, red salmon (Oncorhynchus nerka) head meal, and Pacific whiting (Merluccius productus) meal] were substituted for Special Select™ menhaden fish meal at two different levels (33% or 67% of crude protein) in prepared diets for red drum. Another treatment consisted of shrimp processing waste meal formulated on a digestible-protein basis to replace 33% of the protein from menhaden fish meal. Levels of calcium carbonate were reduced in two additional diets containing Pacific whiting, to evaluate the effects of ash content. Diets were formulated to contain 40% crude protein, 12% lipid, and 3.5 kcal digestible energy/g. Each diet was fed to triplicate groups of juvenile red drum in 38-l aquaria containing brackish water (7 ± 1 ppt) in two separate 6-week feeding trials. Survival, weight gain, feed efficiency, protein efficiency ratio and body composition responses were measured in each trial. Fish fed the by-catch meal at either level of substitution performed as well as fish fed the control diet containing protein solely from menhaden fish meal; whereas, fish fed the shrimp processing waste meal diets did significantly (P ≤ 0.05) worse than the controls, even when fed a diet formulated to be equivalent on a digestible-protein basis. Fish fed the red salmon head meal diet fared poorly, probably owing to an excessive amount of lipid in the diet that tended to become rancid. Overall, by-catch meal associated with shrimp trawling appears to be a very suitable protein feedstuff for red drum.
3

Evaluation of fisheries by-catch and by-product meals in diets for red drum (Sciaenops ocellatus)

Whiteman, Kasey 12 April 2006 (has links)
By-catch and wastes from processed fish and shrimp constitute a sizeable portion of commercial fishery landings. This discarded material is potentially valuable, for its content of fish meals and other substances. Fish meals, in particular, are increasingly in short supply for the manufacture of animal feeds, including feeds for farmed fish. Therefore, in this study, various by-catch and by-product meals of marine origin were evaluated with red drum (Sciaenops ocellatus), a carnivorous fish species native to the Gulf of Mexico that has been cultured over the past two decades for stock enhancement as well as for food. Four different kinds of by-catch or by-product meals [shrimp by-catch meal, shrimp processing waste meal, red salmon (Oncorhynchus nerka) head meal, and Pacific whiting (Merluccius productus) meal] were substituted for Special Select™ menhaden fish meal at two different levels (33% or 67% of crude protein) in prepared diets for red drum. Another treatment consisted of shrimp processing waste meal formulated on a digestible-protein basis to replace 33% of the protein from menhaden fish meal. Levels of calcium carbonate were reduced in two additional diets containing Pacific whiting, to evaluate the effects of ash content. Diets were formulated to contain 40% crude protein, 12% lipid, and 3.5 kcal digestible energy/g. Each diet was fed to triplicate groups of juvenile red drum in 38-l aquaria containing brackish water (7 ± 1 ppt) in two separate 6-week feeding trials. Survival, weight gain, feed efficiency, protein efficiency ratio and body composition responses were measured in each trial. Fish fed the by-catch meal at either level of substitution performed as well as fish fed the control diet containing protein solely from menhaden fish meal; whereas, fish fed the shrimp processing waste meal diets did significantly (P ≤ 0.05) worse than the controls, even when fed a diet formulated to be equivalent on a digestible-protein basis. Fish fed the red salmon head meal diet fared poorly, probably owing to an excessive amount of lipid in the diet that tended to become rancid. Overall, by-catch meal associated with shrimp trawling appears to be a very suitable protein feedstuff for red drum.
4

Intra- and interspecific variability in the distribution patterns and diet of the two most common catsharks caught in demersal trawls off the West and South coasts of South Africa: Evidence for habitat and resource partitioning?

van der Heever, Grant Mark January 2017 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / The objective of this thesis was to elucidate intra- and interspecific variability in the distribution patterns and diet of the two most common demersal catsharks taken as by-catch by the commercial trawling industry targeting the two Cape hake species off the West and South coasts of South Africa. Samples and data were collected during routine demersal hake biomass surveys conducted by DAFF, with distribution data collected from 1994 to 2015 and stomach content and stable isotope data collected from 2014 to 2015. On examination of the distribution data, Holohalaelurus regani was found to be more abundant on the West Coast and Scyliorhinus capensis was found to be more abundant on the South Coast. Both catsharks were observed to display size-based segregations, with catshark size increasing with depth in both species. Differences in the distribution patterns of male and female H. regani were also noted, with female catsharks inhabiting inshore areas and male catsharks inhabiting offshore areas. The two catsharks appeared to display high levels of dietary overlap, with individuals feeding on the most abundant crustaceans and cephalopods caught as by-catch in the trawl on each coast.
5

Characterizing a Hidden Fishery: Setline Fishing in the New River, Virginia

Dickinson, Benjamin David 19 December 2013 (has links)
Catfishes Ictaluridae are important food fish that are harvested from the New River, Virginia by multiple methods, yet standard creel survey approaches do not accurately sample setline effort, a popular fishing gear for catfish. I characterized the New River setline fishery by estimating setline effort and catch rates of catfish and by-catch in 2011, and by investigating the attitudes and opinions of setline users during 2012. Setline effort was highest during June-August, and declined significantly by mid-September. Several dedicated setline users accounted for a significant portion of total setline effort. Experimental setlines baited with live minnows Cyprinidae proved to be an effective method for catching catfish but caught few walleye Sander vitreus, smallmouth bass Micropterus dolomieu, and muskellunge Esox masquinongy. Estimated by-catch of these species by setline fishers is small compared to catch by hook-and-line anglers, though walleye experienced high setline hooking mortality, and catch rates increased in autumn months. Setlines appear to be part of a larger "way of life" for some rural individuals, who may also hunt, trap, and garden as part of activities to supplement their diet or income. New River setline fishers strongly believe that setline fishing has declined significantly in the New River Valley due to improving socioeconomic status of the region, changing recreational values (such as focus on catch-and-release fishing and paddle sports), increasing recreational traffic and law enforcement presence, and decreasing participation in setline fishing by younger generation. / Master of Science
6

Dinâmica populacional do caranguejo baú Hepatus pudibundus (Herbst, 1785) (Decapoda Aethroidea) numa área de pesca intensa: comparação num intervalo de 20 anos /

Teles, Jeniffer Natália January 2019 (has links)
Orientador: Giovana Bertini / Resumo: O objetivo deste estudo foi analisar e comparar a distribuição espaço-temporal de Hepatus pudibundus num intervalo de 20 anos, associado com os fatores ambientais, na Enseada de Ubatuba, SP. As coletas foram realizadas em dois períodos, de setembro/1995 a agosto/1996 (1º período = 1ºP) e setembro/2016 a agosto/2017 (2º período = 2ºP), em 5 áreas amostrais (5m, 10m e 15m, área exposta e área abrigada), com um barco de pesca camaroeiro. Os fatores ambientais coletados foram: temperatura e salinidade de fundo e superfície, sedimento para análise de phi e teor de matéria orgânica. Após 20 anos do primeiro período de estudo na Enseada de Ubatuba foi possível detectar que houve um aumento na deposição de sedimentos finos em todas as áreas amostradas. Em relação à população de H. pudibundus observou-se que no 1ºP foram coletados 865 caranguejos e no 2ºP 4222. Essa maior abundância de indivíduos no 2ºP pode ser devido a coleta ter sucedido um evento intenso de El Niño, que faz que com a ACAS (Águas Centrais do Atlântico Sul) permaneça mais tempo na região externa da enseada, diminuindo a temperatura da água, e podendo fazer com que os indivíduos se abriguem dentro da enseada. Houve uma alteração da distribuição espacial dos indivíduos, principalmente, dos caranguejos adultos, os quais mudaram da área exposta e 15m no 1ºP para área abrigada no 2ºP. Tal mudança pode estar relacionada ao aumento de sedimentos finos nesta área e por ela ser uma região de exclusão natural de pesca, o que ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to analyze and compare the spatio-temporal distribution of Hepatus pudibundus in a 20-year interval, associated with environmental factors, in the Ubatuba Bay, SP. The samples were collected in two sampling periods, from September/1995 to August/1996 (1st period = 1P) and September/2016 to August/2017 (2nd period = 2P), in five areas (5m, 10m, 15m, exposed area and sheltered area) with a shrimp fishing boat. The environmental factors collected were bottom and surface temperature and salinity, sediment for phi analysis and organic matter content. After 20 years of the first study period in the Ubatuba Bay, it was possible to detect that there was an increase in the deposition of fine sediments in all the areas sampled. In relation to the population of H. pudibundus it was observed that in the 1P were collected 865 crabs and in the 2ºP 4222. This greater abundance of individuals in the 2P can be due to the collection to have happened an intense event of El Niño, that causes that with ACAS (Central Waters of the South Atlantic) remain longer in the outer region of the bay, lowering the water temperature, and may cause individuals to shelter within the bay. There was a change in the spatial distribution of the individuals, mainly of the adult crabs, who changed from the exposed area and 15m in the 1P to the sheltered area in the 2P. Such change may be related to the increase of fine sediments in this area and because it is a region of natural exclu... (Complete abstract click electronic access below) / Mestre
7

Patologia comparada de cetáceos e pinípedes / Comparative pathology of cetaceans and pinnipeds

Ruoppolo, Valeria 04 April 2003 (has links)
O conhecimento das causas de morbidade e mortalidade dos mamíferos aquáticos pertencentes à ordem Cetacea e subordem Pinnipedia no Brasil é escasso. Este trabalho teve por objetivo caracterizar as principais causas que contribuem para a morte destes animais, incluindo dentre outras as enfermidades infecciosas, parasitárias, traumáticas, metabólicas e nutricionais. Foram analisadas amostras provenientes de necropsias de 110 indivíduos oriundos de encalhes naturais e capturas acidentais em redes de pesca ocorridos na costa sul e sudeste do Brasil. Ocasionalmente, amostras de cetáceos e pinípedes provenientes de centros de reabilitação, zoológicos, aquários e oceanários também foram analisadas. As amostras consistiram de fragmentos de 1 a 2 cm3 dos órgãos principais acondicionados em formalina a 10%. As afecções foram diagnosticadas através de exames anatomopatológicos, associados, quando possível a resultados microbiológicos e parasitológicos. Dos diagnósticos finais elucidados para os cetáceos 88,6% (70/79) tiveram a morte relacionada com o sistema respiratório, 3,8% (3/79) de origem metabólica, 2,5% (2/79) de etiologia infecciosa, 1,3% (1/79) com origem traumática antropogênica e em 3,8% (3/79) foi indeterminada. Nos pinípedes as causas de morte também estiveram relacionadas principalmente com o trato respiratório (48,5% - 15/31). A morte decorrente de outras causas incluiu: 29,1% (9/31) de causas metabólicas; 3,2% (1/31) nutricional; 3,2% (1/31) digestivo; 3,2% (1/31) urinário; 3,2% (1/31) físico; 3,2% (1/31) síndrome, colapso; 3,2% (1/31) vandalismo; 3,2% (1/31) indeterminado. A análise parasitológica foi realizada em 15,4% (17/110) dos casos e a bacteriologia em 10,9% (12/110) dos casos. As interpretações anatomopatológicas foram associadas aos demais resultados, quando presentes, e então analisados conforme informações recentes de literatura relativas ao assunto. As amostras utilizadas na realização deste projeto complementam o banco de tecidos de animais selvagens mantido pelo Laboratório de Patologia Comparada de Animais Selvagens da FMVZ, formando dessa forma o primeiro acervo de tecidos de mamíferos marinhos disponível no Brasil. Os resultados alcançados neste estudo reforçam a necessidade da abordagem multidisciplinar dos animais encalhados e também dos capturados acidentalmente em redes de pesca, buscando informações que possam colaborar para uma maior compreensão dos processos patológicos que os acometem e os predispõe à morte. / The known causes of morbidity and mortality of aquatic mammals belonging to the Order Cetacea and Suborder Pinnipedia in Brazil is limited. The aim of this work was to characterize the main processes that contribute to or cause the death of these animals, and included investigating infectious, parasitic, traumatic, metabolic and nutritional diseases. Samples coming from 110 fresh animals were analyzed, including individuals from strandings and incidentally caught in fishing nets along the south and southeastern coasts of Brazil. Circumstantially, carcasses coming from zoological collections, aquariums and rehabilitation centers were also included. The samples consisted of fragments of 1-2 cm3 taken of the main organs and fixed in 10% formalin. All the tissues have been processed according to routine histological procedures and analyzed under light microscopy. Diseases were diagnosed through anatomopathologic examinations, associated, whenever possible, with microbiologic and parasitologic results and then compared to related bibliography. Final results, mentioning the cause of the death, included: cetaceans: 88,6% (70/79) had lesions associated with the respiratory tract; 3,8% (3/79) of metabolic origin, 2,5% (2/79) of infectious etiology, 1,3% (1/79) were human related injuries, and 3,8% (3/79) of the cases were undetermined. For the pinnipeds the main cause of death was also related to the respiratory tract (48,5% - 15/31). The causes of death implicated in the other cases included: 29,1% (9/31) metabolical causes; 3,2% (1/31) nutritional origin; 3,2% (1/31) digestive causes; 3,2% (1/31) urinary tract; 3,2% (1/31) physical causes; 3,2% (1/31) syndrome; 3,2% (1/31) human related injuries; 3,2% (1/31) were undetermined. Parasitological analyses were performed in 15,4% (17/110) of the cases and bacteriology in 10,9% (12/110). The samples utilized in this project were stored to create a tissue bank for further studies. The results achieved in this work reinforce the need for a multidisciplinary view of stranded and by-caught animals, searching for information that can collaborate to better understand the pathologic processes affecting marine mammals and predisposing their death.
8

Patologia comparada de cetáceos e pinípedes / Comparative pathology of cetaceans and pinnipeds

Valeria Ruoppolo 04 April 2003 (has links)
O conhecimento das causas de morbidade e mortalidade dos mamíferos aquáticos pertencentes à ordem Cetacea e subordem Pinnipedia no Brasil é escasso. Este trabalho teve por objetivo caracterizar as principais causas que contribuem para a morte destes animais, incluindo dentre outras as enfermidades infecciosas, parasitárias, traumáticas, metabólicas e nutricionais. Foram analisadas amostras provenientes de necropsias de 110 indivíduos oriundos de encalhes naturais e capturas acidentais em redes de pesca ocorridos na costa sul e sudeste do Brasil. Ocasionalmente, amostras de cetáceos e pinípedes provenientes de centros de reabilitação, zoológicos, aquários e oceanários também foram analisadas. As amostras consistiram de fragmentos de 1 a 2 cm3 dos órgãos principais acondicionados em formalina a 10%. As afecções foram diagnosticadas através de exames anatomopatológicos, associados, quando possível a resultados microbiológicos e parasitológicos. Dos diagnósticos finais elucidados para os cetáceos 88,6% (70/79) tiveram a morte relacionada com o sistema respiratório, 3,8% (3/79) de origem metabólica, 2,5% (2/79) de etiologia infecciosa, 1,3% (1/79) com origem traumática antropogênica e em 3,8% (3/79) foi indeterminada. Nos pinípedes as causas de morte também estiveram relacionadas principalmente com o trato respiratório (48,5% - 15/31). A morte decorrente de outras causas incluiu: 29,1% (9/31) de causas metabólicas; 3,2% (1/31) nutricional; 3,2% (1/31) digestivo; 3,2% (1/31) urinário; 3,2% (1/31) físico; 3,2% (1/31) síndrome, colapso; 3,2% (1/31) vandalismo; 3,2% (1/31) indeterminado. A análise parasitológica foi realizada em 15,4% (17/110) dos casos e a bacteriologia em 10,9% (12/110) dos casos. As interpretações anatomopatológicas foram associadas aos demais resultados, quando presentes, e então analisados conforme informações recentes de literatura relativas ao assunto. As amostras utilizadas na realização deste projeto complementam o banco de tecidos de animais selvagens mantido pelo Laboratório de Patologia Comparada de Animais Selvagens da FMVZ, formando dessa forma o primeiro acervo de tecidos de mamíferos marinhos disponível no Brasil. Os resultados alcançados neste estudo reforçam a necessidade da abordagem multidisciplinar dos animais encalhados e também dos capturados acidentalmente em redes de pesca, buscando informações que possam colaborar para uma maior compreensão dos processos patológicos que os acometem e os predispõe à morte. / The known causes of morbidity and mortality of aquatic mammals belonging to the Order Cetacea and Suborder Pinnipedia in Brazil is limited. The aim of this work was to characterize the main processes that contribute to or cause the death of these animals, and included investigating infectious, parasitic, traumatic, metabolic and nutritional diseases. Samples coming from 110 fresh animals were analyzed, including individuals from strandings and incidentally caught in fishing nets along the south and southeastern coasts of Brazil. Circumstantially, carcasses coming from zoological collections, aquariums and rehabilitation centers were also included. The samples consisted of fragments of 1-2 cm3 taken of the main organs and fixed in 10% formalin. All the tissues have been processed according to routine histological procedures and analyzed under light microscopy. Diseases were diagnosed through anatomopathologic examinations, associated, whenever possible, with microbiologic and parasitologic results and then compared to related bibliography. Final results, mentioning the cause of the death, included: cetaceans: 88,6% (70/79) had lesions associated with the respiratory tract; 3,8% (3/79) of metabolic origin, 2,5% (2/79) of infectious etiology, 1,3% (1/79) were human related injuries, and 3,8% (3/79) of the cases were undetermined. For the pinnipeds the main cause of death was also related to the respiratory tract (48,5% - 15/31). The causes of death implicated in the other cases included: 29,1% (9/31) metabolical causes; 3,2% (1/31) nutritional origin; 3,2% (1/31) digestive causes; 3,2% (1/31) urinary tract; 3,2% (1/31) physical causes; 3,2% (1/31) syndrome; 3,2% (1/31) human related injuries; 3,2% (1/31) were undetermined. Parasitological analyses were performed in 15,4% (17/110) of the cases and bacteriology in 10,9% (12/110). The samples utilized in this project were stored to create a tissue bank for further studies. The results achieved in this work reinforce the need for a multidisciplinary view of stranded and by-caught animals, searching for information that can collaborate to better understand the pathologic processes affecting marine mammals and predisposing their death.
9

Analysis of seabird by-catch in the Australian Fishing Zone using Japanese longline fishery observer data

Klaer, Neil E., n/a January 1998 (has links)
Data collected by Australian observers, combined with logbook data supplied by all Japanese vessels fishing in the Australian Fishing Zone were used to estimate the total seabird catch and catch rates (and associated variances) within the Australian Fishing Zone by season and area. The species composition of subsamples of captured seabirds was used in conjunction with the estimates of total by-catch to provide estimates of by-catch by species. The total by-catch of all seabird species by Japanese longline within Australian waters was estimated to be 2,981 (cv 17%) for the 1992 fishing year, 3,590 (cv 15%) in 1993 and 2,817 (cv 19%) in 1994. However, the observed seabird bycatch may underestimate the total number of seabirds killed by 27%. The increase in total seabird by-catch between 1992 and 1993 is partly due to the use of monofilament nylon longline gear by two vessels in 1993, and the decrease from 1993 to 1994 was mainly due to a corresponding reduction in fishing effort. For the three years examined, 78% of the total seabird by-catch was albatrosses, with black-browed albatross (Diomedea melanophrys) and shy albatross (D. cauta) caught in the greatest numbers. Catches of yellow-nosed albatross (D. chlororhynchos), wandering albatross (D. exulans}, and grey-headed albatross (D. chrysostoma) were also substantial. The proportions of individual species caught showed considerable inter-annual variability. Most seabirds caught and killed by longline fishing are captured during line setting. Data collected by the observers were also used to determine the influence of various environmental factors and mitigation measures on seabird catch rates. Generalised linear models were used to determine the statistical significance of the effect of each factor on the seabird catch rate. Results show that the environmental factor that has the most influence is whether line setting was carried out at night or during the day. For the data examined, the chance of catching seabirds during day sets was five times greater than for night sets. For night sets, the chance of catching seabirds during the full half-phase of the moon was five times greater than during the new half-phase. Other environmental factors with significant effects were the area and season fished. Wind, cloud and sea conditions were not found to have a significant influence. Considerable variation in the seabird by-catch rate among vessels was found, which is probably due to differences in their implementation of mitigation measures, as well as the clumped distribution of seabirds by area and time. Interannual variation in the by-catch rate was found to be statistically significant but the differences among years was small in comparison to other factors. An examination of the influence of mitigation measures for sets made during the day in summer in the Tasmanian area showed that the level of bait thawing and unidentified factors related to individual vessels were most significant in determining the seabird by-catch rate, followed by the use of a bait throwing device. It was not possible to examine the influence of the use of bird scaring tori poles and lines as these were used during all sets examined in detail. For this data set, the amount of cloud cover had an influence, while moon phase, sea conditions and wind strength did not.
10

Fauna acompanhante: um universo químico a ser explorado / By-catch: a chemical universe to be explored

Tangerina, Marcelo Marucci Pereira [UNESP] 27 June 2016 (has links)
Submitted by MARCELO MARUCCI PEREIRA TANGERINA null (marcelomptang@hotmail.com) on 2016-07-09T22:03:34Z No. of bitstreams: 1 Tese ABNT Marcelo Tangerina Wagner Vilegas CD.pdf: 3984472 bytes, checksum: 993744f837a77327c951b1988896f63c (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-07-12T17:19:33Z (GMT) No. of bitstreams: 1 tangerina_mmp_dr_araiq.pdf: 3984472 bytes, checksum: 993744f837a77327c951b1988896f63c (MD5) / Made available in DSpace on 2016-07-12T17:19:33Z (GMT). No. of bitstreams: 1 tangerina_mmp_dr_araiq.pdf: 3984472 bytes, checksum: 993744f837a77327c951b1988896f63c (MD5) Previous issue date: 2016-06-27 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A fauna acompanhante da pesca do camarão inclui uma série de invertebrados marinhos que são descartados por não ter valor comercial. A fim de tentar acrescentar algum valor a este material, foi analisada a composição química da estrela-do-mar Luidia senegalensis coletada na costa brasileira como consequência da aplicação da pesca de arrasto. A fim de avaliar sua composição química, foi utilizada uma combinação de extração em fase sólida (SPE) seguida de cromatografia líquida de ultra eficiência acoplada a espectrômetro de massas equipado com fonte de ionização por eletrosptray e analisador ion-trap linear (UPLCESI- IT-MSn). Luidia senegalensis contém asterosaponinas, que são esteroides glicosilados sulfatados contendo cinco e seis unidades de açúcar, além de poliidroxiesteroides. Este estudo mostrou a presença de compostos importantes e potencialmente bioativos em invertebrados associados à fauna acompanhante da pesca do camarão, usando um método rápido e eficiente. Normalmente descartada, a fauna acompanhante contém muitos invertebrados que podem hospedar uma grande variedade de gêneros de bactérias, algumas das quais com potencial de produzir produtos naturais bioativos com aplicações biotecnológicas. Assim, para utilizar um material normalmente descartado, foi explorado o potencial biotecnológico de bactérias cultiváveis de duas espécies de invertebrados abundantes na fauna acompanhante, o gastrópode Olivancillaria urceus e a estrela-do-mar Luidia senegalensis. Uma amostra de sedimento da mesma área de coleta também foi investigado. Utilizando múltiplas abordagens de isolamento 134 isolados foram obtidos a partir dos invertebrados e do sedimento. Sequenciamento parcial da subunidade de rRNA (16S) revelou que os isolados pertenciam aos filos Proteobacteria, Firmicutes e Actinobacteria, distribuídos em 28 gêneros. Vários gêneros conhecidos pela sua capacidade de produzir produtos naturais bioativos (Micromonospora, Streptomyces, Serinicoccus e Verrucosispora) foram obtidos a partir das amostras estudadas. Para avaliar as bactérias isoladas quanto à sua capacidade para produzir metabólitos bioativos todas as cepas foram fermentadas e os extratos de fermentação analisados por LC-HRMS e testados em ensaio de atividade antimicrobiana. Quatro cepas apresentaram atividade antimicrobiana contra Staphylococcus aureus resistente à meticilina (MRSA) e Staphylococcus warneri. A produção de metabólitos secundários por bactérias isoladas da fauna acompanhante também foi avaliada por uma abordagem metabolômica utilizando LC-HRMS, onde foi avaliado como as diferenças na composição dos meios de cultura podem alterar a produção de substâncias. Utilizou-se a metabolômica como uma ferramenta para investigar a produção de abyssomicinas, um agente anticâncer, e outros metabólitos secundários em três cepas do actinomiceto raro Verrucosispora maris, isoladas a partir de uma amostra de sedimento e associadas à estrela-do-mar Luidia senegalensis de Ubatuba - SP, Brasil. Nove composições diferentes de meios de cultura foram avaliadas e verificou-se que, dentre todas as cepas, somente RKMT_111 foi capaz de produzir abyssomicinas. O estudo da composição do meio de cultura revelou que a produção de abyssomicinas só foi possível em BFM-11m. Embora as três cepas pertençam à mesma espécie e são provenientes da mesma localização, é notável que cada isolado apresentou diferente capacidade de produção de metabólitos secundários. Os produtos de fermentação de Erythrobacter vulgaris foram avaliados utilizando técnicas de HPLC preparativo, LC-HRMS e RMN. A cepa foi isolada pelo método dry-stamp de uma amostra de sedimento marinho da costa de Ubatuba-SP, Brasil. Depois de sequenciamento completo do rRNA (16S) e identificação, o isolado foi fermentado em larga escala, seu caldo de fermentação extraído por solvente e os compostos purificados por HPLCMS. Análise de LC-HRMS e RMN dos compostos isolados levou à identificação de dois novos derivados do ácido cólico, ácido 3-acetil-glicocólico e o ácido 3-acetilglicodesoxicólico. As substâncias obtidas podem ter sido produzidas por biotransformação do ácido glicocólico e ácido desoxicólico, respectivamente, já presentes no meio de cultivo. Este é o primeiro relato de tais compostos e também a primeira observação de uma acilação realizada por um isolado marinho de Erythrobacter vulgaris. / The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are discarded because they do not have commercial value. In order to try to add some value to these materials, we analyzed the chemical composition of the starfish Luidia senegalensis collected in the Brazilian coast as a consequence of the trawling fishery method. In order to access their chemical composition, we used a combination of solid phase extraction (SPE) followed by ultra performance liquid chromatography coupled to electrospray ionization ion trap tandem mass spectrometry (UPLC-ESI-IT-MSn). Luidia senegalensis contains asterosaponins, which are sulphated glycosilated steroids, containing five and six sugar moieties, in addition to polyhydroxysteroids. This study helped us to support the presence of important and potentially bioactive compounds in invertebrates associated to the by-catch fauna of the shrimp fishery, using a fast and efficient method. Typically discarded, by-catch contains many invertebrates that may host a great variety of bacterial genera, some of which may produce bioactive natural products with biotechnological applications. Therefore, to utilize by-catch that is usually discarded we explored the biotechnological potential of culturable bacteria of two abundant by-catch invertebrate species, the snail Olivancillaria urceus and the sea star Luidia senegalensis. Sediment from the collection area was also investigated. Utilizing multiple isolation approaches 134 isolates were obtained from the invertebrates and sediment. Small subunit rRNA (16S) gene sequencing revealed that the isolates belonged to Proteobacteria, Firmicutes and Actinobacteria phyla and were distributed among 28 genera. Several genera known for their capacity to produce bioactive natural products (Micromonospora, Streptomyces, Serinicoccus and Verrucosispora) were retrieved from the invertebrate samples. To query the bacterial isolates for their ability to produce bioactive metabolites all strains were fermented and fermentation extracts profiled by LC-HRMS and tested for antimicrobial activity. Four strains exhibited antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus warneri. The production of secondary metabolites was assessed using a LC-HRMS-based metabolomics approach, where it was evaluated how differences in media composition can alter the production of chemical compounds. We used metabolomics as a tool to investigate the production of abyssomicins, an anticancer agent, and other secondary metabolites in three strains of the rare actinomycete Verrucosispora maris, all marine isolates from a sediment sample and associated to a starfish from the species Luidia senegalensis of Ubatuba – SP, Brazil. Nine different media compositions were evaluated and it was found that, among all strains, only RKMT_111 was capable of producing abyssomicins. The media composition study revealed that the production of abyssomicins was only achievable in BFM-11m. Although the three strains belong to the same species and the same location, it is worthwhile noticing that each isolate showed different capability for production of secondary metabolites. The products of fermentation of Erythrobacter vulgaris were evaluated using preparative HPLC, LC-HRMS and NMR techniques. Bacterial strain was isolated by drystamp method from a marine sediment sample from the coast of Ubatuba-SP, Brazil. After fully 16S rDNA sequence and identification, the marine isolate was fermented in large-scale, extracted and the compounds purified through HPLC-MS. Analysis of LC-HRMS and NMR of the isolated compounds led to the identification of two new cholic acid derivatives, 3- acetyl-glycocholic acid and 3-acetyl-glycodeoxycholic acid. Both new compounds may have been produced by the biotransformation of glycocholic acid and deoxycholic acid, respectively, already present in the cultivation medium. This is the first report of such compounds and also the first time an acylation has been observed for an Erythrobacter vulgaris marine isolate. / FAPESP: 2011/23159-0

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