Дисертації з теми "Natural products and bioactive compounds"
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Heltzel, Carl E. "Structural and synthetic studies of bioactive natural products." Diss., Virginia Tech, 1993. http://hdl.handle.net/10919/40067.
Повний текст джерелаPh. D.
Dowle, Katie Orlagh. "New nitrogenous spongian diterpenes from the New Zealand marine sponge Darwinella oxeata : a thesis submitted to the Victoria University of Wellington in fulfilment of the requirements for the degree of Master of [Science] in Chemistry /." ResearchArchive@Victoria e-Thesis, 2008. http://hdl.handle.net/10063/626.
Повний текст джерелаEaton, Alexander Lee. "Isolation and Synthesis of Bioactive Compounds from Plants." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/64367.
Повний текст джерелаPh. D.
Thwala, Sazi Selby. "Investigation of the natural products composition from the seaweed ulva capensis." University of Western Cape, 2019. http://hdl.handle.net/11394/7888.
Повний текст джерелаIn modern society, diversity of marine macroalgae has become an inspiration for pharmaceutical companies and researchers because of their numerous health benefits, and a great deal of interest has developed towards the isolation of bioactive compounds to identify novel marine natural products that could eventually be developed into therapeutics or pharmaceutical products. Furthermore, marine macroalgae are valuable source of structurally diverse metabolites with scientifically proven reports. The search continues as there are many natural bioactive compounds that are in the womb of the ocean which are still a mystery. Thus, the present study investigates the natural products from green seaweed Ulva capensis.
Akintunde, Olaitan G. "Production of an Antibiotic-like Activity by Streptomyces sp. COUK1 under Different Growth Conditions." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2412.
Повний текст джерелаPAN, CHENGQIAN. "Discovery of Novel Bioactive Compounds from a Rare Actinomycete Amycolatopsis sp. 26-4." Kyoto University, 2020. http://hdl.handle.net/2433/259019.
Повний текст джерелаChamyuang, Sunita. "Application of selective methods in the search for new bioactive natural products from fungi." Thesis, University of Canterbury. School of biological Science, 2010. http://hdl.handle.net/10092/3702.
Повний текст джерелаInuki, Shinsuke. "Total Synthesis of Bioactive Natural Products by Palladium-Catalyzed Domino Cyclization of Allenes and Related Compounds." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/142485.
Повний текст джерелаEl, Marrouni El Ghazaoui Abdellatif. "Synthesis of unusual alpha-amino acids and study of the effect of their incorporation into antimicrobial peptides. Total synthesis of biactive marine natural products and analogues thereof." Doctoral thesis, Universitat de Girona, 2012. http://hdl.handle.net/10803/80815.
Повний текст джерелаAquesta tesi s'ha centrat en la preparació de nous compostos bioactius seguint dues estratègies diferents. El primer projecte es va portar a terme sota la supervisió de la Dra. Montserrat Heras del grup LIPPSO del Departament de Química i ha permés el desenvolupament de noves metodologies per la síntesi de nous aminoàcids no naturals. i el seu ús en la preparació d'anàlegs del pèptid antimicrobià BP100 amb l'objectiu de millorar-ne les propietats biològiques. El segon projecte és fruit de la col•laboració amb la Prof. Janine Cossy i el Dr. Stellios Arseniyadis del "Laboratoire de Chimie Organique" de l'Ecole Superieur de Physique et Chimie Industrielles (ESPCI-ParisTech, Paris, França). I ha permés posar a punt tres estratègies sintètiques convergents i versàtils per l’obtenció de tres productes naturals de gran complexitat estructural i interessants activitats biològiques – l'acremolide B, la bitungolide F i la lyngbouilloside – aïllats recentment del fons marí de diferents punts del món.
Elias, Luciana Mecatti. "Bioprospecção de fungos endofíticos isolados de guaranazeiros da Amazônia." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-05012016-111344/.
Повний текст джерелаColletotrichum fungi are considered one of the main pathogens in the world, affecting different cultures and causing social and economic damage to several countries, including Brazil. Despite control measures already being employed, these are not always effective, which is why the search for new control options that can act in the integrated management is necessary. Among these, the secondary metabolites produced by endophytes are involved in the production of compounds of biotechnological interest, with applications in several areas, including the agronomic. In this context, this study aimed to explore the biological and chemical potential of secondary metabolites produced by endophytic fungi isolated from the Amazonian guarana, evaluating their antifungal activity \"in vitro\" to Colletotrichum gloeosporioides, isolated from the culture of guarana and C. acutatum and C. gloeosporioides, isolated from the red pepper crop. For this purpose, 16 strains of endophytic fungi were evaluated in biological assay of dual culture and disk diffusion method against Colletotrichum spp. Four strains of these strains presented promising results which were selected for bioprospecting. From the crude extract of the endophyte Aspergillus flavus (272) was isolated the active compound asperfuran, which showed inhibitory activity to three pathogens, with IC50 <100 μg disk-1, similar to the commercial fungicide difenoconazole. From the crude extract of Xylaria sp. (214) was isolated the active compound cytochalasin D, which showed inhibitory activity against C. gloeosporioides isolated from guarana (IC50> 500 μg disk-1). From the crude extract of Xylaria sp. (249) was isolated the active compound piliformic acid, which showed inhibitory activity against C. gloeosporioides isolated from guarana (IC50 of 500 μg disk-1) and C. acutatum isolated from red pepper (IC50 of 300 μg disk-1). And from the crude extract of Talaromyces aculeatus (507) were isolated three compounds, of phthalate esters class, one of them with activity. The predecessor fraction of these three compounds showed inhibitory activity against C. gloeosporioides isolated from guarana (IC50> 500 μg disk-1). From the crude extract of T. aculeatus it was also isolated a partially identified active compound and a semi-purified active compound. The predecessor fraction of these two compounds showed inhibitory activity to both C. gloeosporioides (IC50> 300 μg disk-1) and to C. acutatum (IC50 around 150 μg disk-1). The antifungal activity of the compounds isolated in this study is being reported for the first time against fungus of the genus Colletotrichum.
Salinas-Roca, Blanca. "Preserving natural attributes of mango products by non-thermal technologies." Doctoral thesis, Universitat de Lleida, 2017. http://hdl.handle.net/10803/405840.
Повний текст джерелаConsumers are currently demanding safe, healthy and novel fruit products, such as ready-to-eat, with natural attributes. Therefore, the aim of the present doctoral thesis was to assess the impact of non-thermal treatments on quality properties of various mango products: fresh-cut, juice and puree. On one hand, the effect of different polysaccharide-based coatings, alginate (AL), chitosan (CH), pectin (PE) and carboxymethylcellulose (CMC) was evaluated on the quality preservation of fresh-cut mango. Also in fresh-cut mango, the effect of pulsed light (PL) combined with AL coating and malic acid (MA) dipping extended preservation of natural attributes throughout 14 days. On the other hand, the influence of high intensity pulsed electric fields (HIPEF) at 35 kV/cm, 4 μs- bipolar pulses, 200 Hz and 50-2000 μs in mango juice was studied in the reduction of Listeria innocua population, enzymatic activities, physicochemical and sensorial attributes as well as the content of bioactive compounds. In this sense, phenolic content in mango juice treated with HIPEF (1800 μs) was improved after 59 days. Finally, the impact of high hydrostatic pressure (HHP) treatments (400, 450, 500 MPa for 0 to 16 min at 34 or 59°C) on physicochemical, enzymatic properties and bioactive compounds of mango puree was observed. This research reveals the feasibility of preserving fruit products by non-thermal technologies.
Los consumidores piden nuevos productos a base de frutas, como los listos para el consumo, seguros, saludables y con propiedades similares a los naturales. Por lo tanto, el objeto de estudio de la presente tesis doctoral fue evaluar el impacto de tratamientos no térmicos en la calidad de diversos productos de mango: cortado, zumo y puré. Por un lado, el efecto de diferentes recubrimientos a base de polisacáridos, alginato (AL), quitosano (CH), pectina (PE) y carboximetilcelulosa (CMC) se evaluó en la conservación de la calidad del mango cortado. También, el efecto de los pulsos de luz (PL) combinado con el recubrimiento AL y la inmersión en ácido málico (MA) permitió alargar la conservación de los atributos naturales durante 14 días. Por otro lado, se estudió en el zumo de mango la influencia de los pulsos eléctricos de alta intensidad de campo (HIPEF) a 35 kV/cm, 4 μs- pulso bipolar, 200 Hz y 50- 2000 μs en la reducción de población de Listeria innocua, la actividad enzimática, las propiedades sensoriales así como el contenido de bioactivos. En este sentido el contenido de fenoles en el zumo de mango tratado por HIPEF (1800 μs) mejoró después de 59 días. Finalmente, el impacto del tratamiento por alta presión hidrostática (HHP) (400, 450, 500 MPa de 0 a 16 min a 34 o 59°C) se observó en las propiedades fisicoquímicas y enzimáticas y en el contenido de compuestos bioactivos en el puré de mango. La presente investigación muestra la viabilidad de la conservación de derivados de frutas mediante tecnologías no térmicas.
Pereira, Daiane. "Desenvolvimento de microcápsulas bioativas de coprodutos de suco e vinho da uva visando sua aplicação como antioxidante natural em patê de carne de frango." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1505.
Повний текст джерелаO objetivo do trabalho foi avaliar a capacidade antioxidante de extratos hidroalcoólicos e microencapsulados, por spray dryer, de coprodutos do vinho e suco da uva das variedades Bordô e Niágara (Vitis labrusca) e aplicar em patê cremoso de carne de frango para avaliar a inibição da oxidação lipídica e a aceitação sensorial do produto. Os coprodutos da uva foram extraídos individualmente com etanol 80% em shaker, a 40 ºC/60 minutos, concentrado em evaporador rotativo e microencapsulado em spray dryer com maltodextrina 10 DE e amido modificado (Capsul®). As amostras pulverizadas em spray dryer sofreram influência do agente encapsulante utilizado, e as amostras microencapsuladas com maltodextrina 10 DE obtiveram maior eficiência. A microencapsulação dos coprodutos originou microesferas lisas, rugosas, homogêneas quanto à forma e estrutura e sem fissuras ou rachaduras. A análise de infravermelho com transformada de Fourrier (IVTF) mostrou que os compostos bioativos permaneceram nos extatos mesmo depois da microencapsulação. Os extratos hidroalcoólicos e microencapsulados apresentaram alta atividade antioxidante in vitro, sendo esta atividade atribuída à presença de compostos fenólicos totais, antocianinas e flavonoides totais. Pela técnica de Cromatografia Líquida de Alta Eficiência (CLAE) foi possível identificar e quantificar seis compostos fenólicos (ácido gálico, cafeico, cumárico, ferrúlico, vanílico e trans-resveratrol). O extrato do coproduto da uva bordô vinho, safra 2014 microencapsulado com maltodextrina (CUBV2M (MD)) e o extrato hidroalcoólico liofilizado coproduto uva bordô vinho, safra 2014 (CUBV2) foram escolhidos para aplicação em patê cremoso de frango por apresentar maior teor de compostos fenólicos com elevada atividade antioxidante. A formulação base do patê cremoso de frango foi elaborada com carne de frango, pele de frango e condimentos e foi dividida em quatro tratamentos: o primeiro foi designado como controle e nenhum ingrediente adicional foi incluído (T1). O segundo lote foi prepardo adicionando eritorbato de sódio (T2). O terceiro lote recebeu o extrato etanólico liofilizado CUBV2 (T3). O quarto lote recebeu o extrato microencapsulado CUBV2M (MD) (T4). A estabilidade oxidativa dos patês foi avaliada pelo teor de substâncias reativas ao ácido tiobarbitúrico (TBARS) e pela coloração no dia do processamento e semanalmente por 41 dias. Pela diferença total de cor (ΔE), em relação ao controle (T1), apenas o T4 apresentou influência visualmente perceptível, durante o período de estocagem. Os patês adicionados de 0,3% de CUBV2 e CUBV2M (MD) demonstraram resultados satisfatórios pela análise de TBARS e estavam microbiologicamente de acordo com à legislação vigente. Os índices de aceitabilidade para a avaliação global foram superiores a 70% para T1, T2 e T3 podendo estes extratos de coprodutos de vinho de uva ser considerados uma alternativa aos antioxidantes sintéticos em patês cremosos.
The objective of this study was to evaluate the antioxidant activity of hydroalcoholic extracts and microencapsulated by spray dryer, of different samples of co-products of wine and juice grape varieties Bordô and Niagara (Vitis labrusca) and apply creamy pate of chicken to verify the inhibition lipid oxidation and the acceptance of this product. The grape co-products were extracted individually with ethanol (80%) in shaker at 40 °C / 60 min, concentrated and microencapsulated in spray dryer with maltodextrin 10 DE and capsul®. The dried samples spray dryer were influenced by the encapsulating agent used, where the microencapsulated samples with maltodextrin obtained better efficiency. Microencapsulation of co-products originated smooth beads and other rough, homogeneous in form and structure, without fissures or cracks. The Infrared Fourier Transform analysis (FTIR) showed that the microencapsulated bioactive compounds in the extracts remained even after subjected to drying by spray drying. The hydroalcoholic and microencapsulated extracts showed high phenolic compounds, anthocyanins and flavonoids with antioxidant activity. For the HPLC technique it was possible to identify and quantify six patterns of phenolic compounds (gallic acid, caffeic, coumaric, ferulic, vanillic and trans-resveratrol). The CBGW2 and CBGW2M (MD) extracts were chosen to be applied in creamy pate due to the best levels of phenolic compounds with antioxidant activity. The basic formulation of creamy chicken pate was made with chicken meat, chicken skin and spices and was divided into four treatments: The first was designated as the control and no additional ingredients were included (T1). The second lot was designated as a positive control and was prepared by adding sodium eritorbate (T2). The third lot received liophilized extract CBGW2 (T3). The fourth lot received the CBGW2M (MD) extracts. The stability of chicken meat pates was performed on the day of processing and weekly at 41 days in 4º C by thiobarbituric acid reactive substances index (TBARS) and color. By (ΔE) in color analyses, compared to the control (T1), only the T4 presented visually perceptible influence during the storage period. The pates added 0.3% CBGW2 and CBGW2M (MD) showed satisfactory results for TBARS analysis and were microbiologically according to law. Acceptability levels for the overall evaluation were greater than 70% for T1, T2 and T3 and these extracts of grape wine co-products can be considered an alternative to synthetic antioxidants in pates creamy.
Manirujjaman. "Identification of bioactive compounds in native plants and their effects on wound healing." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/132475/1/Manirujjaman_Manirujjaman_Thesis.pdf.
Повний текст джерелаReis, Gislâine Vicente dos. "Isolamento bioguiado de compostos de actinobactérias com atividade fungitóxica." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-26102017-172809/.
Повний текст джерелаThe pathogenic species of the genus Colletotrichum present importance worldwide because they cause damage to numerous crops of agronomic interest. Several control methods are employed, but they are not always effective due to the occurrence of resistant strains. Thus, it is necessary searching for new compounds that can be used in the integrated management of this disease. Natural products isolated from microorganisms can be an alternative for the development of new agricultural pesticides. Among microorganisms, actinobacteria are known to produce numerous antimicrobial compounds. In this context, the present study aimed to isolate and identify antifungal compounds produced by actinobacteria from guarana rhizosphere. For this, the selection of actinobacteria was based on two tests. In the first one, the 65 actinobacteria were evaluated in paired cultivation test against the plant pathogen Colletotrichum gloeosporioides. Among them, the most promising isolates were AM1 (43.78% inhibition), AM3 (43.98%), AM18 (37.86%), AM25 (43.17%), AM30 (47.12%), AM61 (40.12%) and AM68 (47.94%). In the second assay, these isolates were cultured in BD medium and, after culturing, the metabolic medium was subjected to three extraction methods: (a) liquid-liquid partition with n-butanol; (B) liquid-liquid partition with ethyl acetate and (c) silica gel column C18. The fractions obtained from the three methodologies were evaluated by paper disc diffusion method against C. gloeosporioides. In this disk diffusion assay, the strains AM1 (n-butanol), AM3 (ethyl acetate) and AM25 (C18) were selected for the bioprospecting study. These were identified by molecular techniques as belonging to the genus Streptomyces. From the crude extract of Streptomyces sp. AM1 the analogous compound proclavaminic acid was isolated, which presented minimal inhibitory activity (MIC) of 1.25 mg mL -1 against the plant pathogen C. gloeosporioides. From Streptomyces sp. AM3, the compound streptimidone was isolated, which presented MIC of 1.25 mg mL-1. In the study of Streptomyces sp. AM25 an unidentified compound had MIC of 2.50 mg mL-1. These three compounds presented superior activity to the fungicides Captan SC® (Captan) and Dithane NT® (Mancozeb), and inferior to the Score® (Difenoconazole). The antifungal activity of these compounds to C. gloeosporioides is being reported here for the first time.
Zang, Hong Zang Hong. "Part 1, Investigations of DNA damage mechanisms of azinomycin analogs and the natural product leinamycin ; Part 2, Biologically relevant chemical reactions of 1,2-dithiole-3-thiones as cancer preventive agents /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3036872.
Повний текст джерелаHundley, Nicholas James. "Structure Elucidation of Bioactive Compounds Isolated from Endophytes of Alstonia scholaris and Acmena graveolens." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd1013.pdf.
Повний текст джерелаGarcia, Ronald O. [Verfasser], and Rolf [Akademischer Betreuer] Müller. "Exploiting the natural products of novel myxobacteria : phylogenetic and fatty acid perspectives and bioactive compound discovery / Ronald O. Garcia ; Betreuer: Rolf Müller." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2011. http://d-nb.info/1160235104/34.
Повний текст джерелаPenchev, Petko Ivanov. "Étude des procédés d’extraction et de purification de produits bioactifs à partir de plantes par couplage de techniques séparatives à basses et hautes pressions." Thesis, Toulouse, INPT, 2010. http://www.theses.fr/2010INPT0122/document.
Повний текст джерелаThis thesis deals with the extraction of natural bioactive compounds from plants (case study with Lemon Balm (Melissa officinalis L.)) by using different separation techniques at high (supercritical extraction) and atmospheric pressure (Soxhlet extraction, batch extraction, nanofiltration etc.). The influence of main operational parameters (solvent composition and flow rate, particle size of the raw material, pressure, temperature) on the process kinetics is studied experimentally with the aim to determine appropriate operational conditions for better extraction. The experimental results are confronted to a number of mathematical models in order to estimate the applicability of different theoretical concepts to the particular process and to select and apply appropriate models for determination of important parameters, characterizing the mass transfer process and necessary for scale-up and design purposes. Coupling between different separation methods is also considered and a number of integrated process schemes are proposed resulting in better yield of the targeted compounds
Wilson, Tyler Aron. "Design and Synthesis of Novel Bioactive Compounds for the Development of HIV-1 Allosteric Integrase Inhibitors, 20S Proteasome Inhibitors, and Anticancer Natural Product Derivatives." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1565967461685907.
Повний текст джерелаWoods, Katherine B. "Bioactive natural products." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/26234.
Повний текст джерелаDesjardine, Kelsey Lorne. "Bioactive marine natural products." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31286.
Повний текст джерелаScience, Faculty of
Chemistry, Department of
Graduate
Zheng, Zehua. "Synthesis of bioactive natural products." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/59815.
Повний текст джерелаScience, Faculty of
Chemistry, Department of
Graduate
Brastianos, Harry Charilaos. "Bioactive natural products from nature." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/3960.
Повний текст джерелаLi, Guoqiang. "Structure elucidation of bioactive natural products." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0004/NQ29469.pdf.
Повний текст джерелаDu, Yongle. "Discovery and Delivery of Bioactive Natural Products." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/83762.
Повний текст джерелаPh. D.
Tang, Shoubin. "Structural and Synthetic Studies of Bioactive Natural Products." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/26104.
Повний текст джерелаPh. D.
Casanova, Martí Àngela. "Action of natural bioactive compounds on the enteroendocrine system." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/460759.
Повний текст джерелаEn los últimos años ha aumentado la presencia de la obesidad y de enfermedades asociadas a ésta. Ante este hecho, la búsqueda de remedios preventivos, así como de tratamientos para estas enfermedades, se vuelve de gran interés para la salud pública. Las hormonas intestinales secretadas por las células enteroendocrinas juegan un papel en la regulación de la ingesta y la homeostasis de la glucosa. En este contexto, la investigación de esta tesis doctoral se ha centrado en la acción de los compuestos naturales bioactivos sobre el sistema enteroendocrino. En estudios previos, nuestro grupo de investigación observó que un extracto de proantocianidinas de hueso de uva (GSPE) aumentaba los niveles plasmáticos de GLP-1 en ratas. En esta tesis doctoral se ha descubierto que este aumento podría ser explicado en parte por la acción directa del GSPE sobre las células enteroendocrinas. Por otro lado, se ha demostrado que la acción directa del GSPE también modula la secreción de GIP y PYY, así como una reducción de la secreción de CCK. Los resultados obtenidos en el cultivo de organoides han demostrado que el GSPE aumenta los principales marcadores de las células L y modula los factores de transcripción involucrados en la diferenciación de éstas. Consecuentemente, estos resultados señalan que promover la diferenciación de las células L es un mecanismo de acción del GSPE en tratamientos prolongados. Por otro lado, la investigación realizada en tratamientos subcrónicos ha revelado que el GSPE modifica la composición de la microbiota intestinal y que el perfil microbiano correlaciona con los parámetros metabólicos del huésped, del cual destaca la correlación con los niveles plasmáticos aumentados de la hormona GLP-1 activa. Además, se ha encontrado una nueva fuente de compuestos naturales bioactivos, el hidrolizado de pata de pollo, el cual se ha demostrado que actúa como un agente antihiperglicémico en ratas que presentan una homeóstasis de la glucosa alterada, debido a la capacidad de inhibir la actividad de DPP-IV y de aumentar la secreción endógena de GLP-1. En conclusión, los resultados obtenidos en esta tesis doctoral muestran que los compuestos naturales bioactivos actúan en el sistema endocrino, con lo cual éstos podrían ser unos agentes terapéuticos adecuados para el tratamiento de la obesidad y diabetes.
In the last decade, there has been an increasing prevalence of obesity and metabolic-associated diseases. In view of this fact, finding preventive therapies, as well as treatments for these diseases is of great interest for public health. Gut hormones secreted from enteroendocrine cells (EECs) play a key role in the regulation of food intake and glucose homeostasis. In this context, the research of this thesis has focused on the role of natural bioactive compounds on the enteroendocrine system. Our research group reported in previous studies that grape seed proanthocyanidin extract (GSPE) increased GLP-1 plasma levels in rats. In this thesis, we elucidated that such increase might be in part explained by the direct action of GSPE on enteroendocrine cells. Moreover, we demonstrate that GSPE also modulates the secretion of the main gut hormones by directly acting on EECs, inducing an increase of GIP and PYY release, while reducing CCK release. The results obtained in this thesis using organoids culture demonstrated that GSPE up-regulate the main markers of L-cell and modulate transcription factors involved in L-cell differentiation, and thereby point out that the promotion of L-cell differentiation is a mechanism by which GSPE act in prolonged treatments. Moreover, our findings in mid-term treatments revealed that gut microbiota composition is modulated by GSPE and such microbial composition profile correlates with host metabolic parameters, and remarkably with increased active GLP-1 plasma levels. Furthermore, we found a new source of natural bioactive compounds, chicken leg hydrolyzate, and demonstrated that it acts as antihyperglycemic agent in disrupted-glucose homeostasis animals due to the capacity of inhibiting DPP-IV activity and enhancing endogenous GLP-1 release . In conclusion, the findings obtained in this thesis show that natural bioactive compounds act through different mechanisms on the enteroendocrine system, and thereby could be good therapeutic agents to treat obesity and glucose homeostasis disruption.
Costa, Elisabete Valente da. "High value-added products from macroalgae: lipids as bioactive compounds." Doctoral thesis, Universidade de Aveiro, 2018. http://hdl.handle.net/10773/22884.
Повний текст джерелаMarine macroalgae are considered to be interesting for food in Western countries and an important supply of novel natural bioactive compounds. Among these are polar lipids such as glycolipids, betaine lipids and phospholipids recognized as high valued lipids for nutrition and as functional ingredient with recognized health benefits. Its biosynthesis depends on several environmental factors such as seasonality, nutrition and habitat, increasing the structural complexity of macroalga lipidome, so that its identification is a current challenge. Mass spectrometry (MS) is a promising tool successfully applied in the study of lipidomic signature of distinct organisms, which can be extended to identify the hundreds of species in the lipidome of macroalgae, and allow them to finally be explored as potential source of lipids. In this work we aim to identify the lipidome of macroalgae representative of Chlorophyta (Codium tomentosum), Rhodophyta (Gracilaria sp. and Porphyra dioica) and Ochrophyta (Fucus vesiculosus). These algae thrive in the Portuguese coast but are recently being cultivated on an integrated multitrophic aquaculture system (IMTA). The characterization of the lipidome will be performed by using mass spectrometry analysis tools coupled to chromatographic methods. We aim to evaluate the bioactive properties of the polar lipids from macroalgae fostering the potential application of these compounds in function of its biological properties as anti-inflammatory and antiproliferative/antitumor agents. The main goals of this project were achieved after the characterization by using HILIC–MS and MS/MS approaches of the lipid extracts carrying on different extraction protocols. The results of this study allowed to identify about 238 molecular species distributed by twelve classes in the macroalgae Codium tomentosum, 147 molecular species in fourteen classes in Gracilaria sp., 110 molecular species in fourteen classes in Porphyra dioica and 181 molecular species distributed by seventeen classes in Fucus vesiculosus. Overall, the lipidome of these macroalgae included GLs monogalactosyl diacylglycerol (MGDG), digalactosyl diacylglycerol (DGDG), sulfoquinovosyl diacylglycerol (SQDG) and its lyso-form (SQMG); phosphatidylcholine (PC) and lyso-PC, phosphatidylglycerol (PG), lyso-PG (LPG), phosphatidic acid (PA), phosphatidylinositol (PI) and betaines (diacylglyceryl trimethyl-homoserine, DGTS). Green macroalgae may be differentiated by the predominance of molecular species including C16 – C20, polyunsaturated fatty acids (PUFA) such as 16:3, 18:3 and 20:5 from n-3 FA family. It contains several molecular species belonging to GLs and betaines including monoacylglyceryl trimethylhomoserine (MGTS), never reported before in the lipidome of macroalga. Red macroalgae are differentiated by molecular species that incorporate C20 FA chains of n-3 and n-6 families, mainly reflected on the composition of GLs.
As macroalgas vermelhas diferenciam-se pelo elevado número de espécies moleculares que incluem cadeias de ácidos gordos C20 da família n-3 e n-6, principalmente na composição dos GLs, e pela presença das classes fosfatidiletanolamina (PE) e inositolfosfoceramida (IPC), apenas identificada nestas algas, pelo que podem ser consideradas um biomarcador deste filo. Neste trabalho, foi avaliada a variação na assinatura lipidómica em duas fases do ciclo de vida (gametófita e esporófita) tomando como alga de estudo a Porphyra dioica. Os resultados obtidos indicaram variações a nível molecular nas classes PC, PA, PE e PG. Em ambas as fases não se observam variações na assinatura dos GLs. O estudo do perfil em ácidos gordos desta alga mostrou que ambas as fases contêm ácidos gordos do tipo 20:4(n-6) e 20:5(n- 3), pelo que apresentam elevado valor nutricional. Na composição da macroalga castanha Fucus vesiculosus, as espécies moleculares combinam diversos ácidos gordos polinsaturados com 18 e 20 átomos de carbono da família n-3 (18:3, 18:4 e 20:5), e 20:4 da família n-6. As algas castanhas apresentam várias espécies moleculares na categoria das betaínas nomeadamente a classe diacilglicerol trimetil-β-alanina (DGTA) e a sua forma liso MGTA, identificada pela primeira vez no lipidoma de macroalgas, ambas não detetadas no lipidoma dos restantes filo. O efeito da sazonalidade na variação da assinatura lipidómica foi estudado para a Fucus vesiculosus colhida em duas estações do ano: inverno e primavera. Os resultados obtidos mostram que o lipidoma desta macroalga mantém o mesmo número de espécies moleculares em todas as classes de lípidos polares, observando-se um aumento da abundância relativa das espécies moleculares que combinam ácidos gordos polinsaturados C18 e C20 (18:3, 18:4, 20:4 e 20:5), em especial nas categorias GLs e betaínas na macroalga de inverno. Assim, podemos concluir que a sazonalidade tem efeito no lipidoma, manifestado pelo aumento de ácidos gordos incorporados nos lípidos polares na macroalga de inverno, muito benéfico em termos nutricionais. Quanto à bioprospecção, avaliaram-se as atividades antiinflamatória e antiproliferativa do extrato lipídico total da macroalga Gracilaria sp.. A atividade anti-inflamatória foi avaliada pela capacidade de inibição dos extratos na produção de NO em macrófagos RAW 264.7 estimulados com o lipopolissacarídeo bacteriano e a atividade anti proliferativa foi testada quanto à capacidade inibitória na proliferação de células T-47D, originadas a partir de um carcinoma ductal humano (cancro da mama) e de células 5637 originadas a partir do carcinoma humano da bexiga. Os extratos totais demonstraram atividade anti-inflamatória e antiproliferativa, pelo que se avaliou o efeito do extrato rico em glicolípidos e a capacidade inibitória na proliferação de células T-47D, verificando-se uma capacidade inibitória da mesma ordem obtida para o extrato total, pelo que poderão ter particular interesse como fitoquímicos. Assim, os resultados obtidos podem contribuir para a valorização das macroalgas como fonte natural e renovável de alimentos, tendo em consideração o valor nutricional como fonte de ácidos gordos n-3 e n-6, e de compostos bioativos a ser utilizados como ingredientes funcionais, fitoquímicos e noutras potenciais aplicações na indústria alimentar e farmacêutica.
Pereira, Alban R. "Marine natural products : synthesis and isolation of bioactive analogues." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/7526.
Повний текст джерелаDaoust, Julie. "Isolation and structure elucidation of bioactive marine natural products." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37536.
Повний текст джерелаClement, Jason Anderson. "Studies of Bioactive Natural Products and Mechanism-Based Bioassays." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29879.
Повний текст джерелаPh. D.
Stapleton, Bronwin Louise. "Structural studies of bioactive natural products from marine invertebrates /." St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16452.pdf.
Повний текст джерелаCorrêa, Joze Aparecida Marciano. "Estudo químico de extratos de plantas da família Solanaceae com atividade a fungos fitopatogênicos." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-29042015-103758/.
Повний текст джерелаThe Brazilian biodiversity is known due to its richness of species, and is considered a promising source of natural products. Among the vascular plants, the family Solanaceae A. Juss. (Solanaceae) is considered one of the largest, with distribution in all tropical and temperate regions of the world. The Solanaceae family has a high diversity of species of economic importance as a source of food, medicinal and ornamental properties. Plants of this family are sources of secondary metabolites from different chemical classes with many different applications. Plant fungi are responsible for causing various diseases and considerable losses in agriculture. The disease control is accomplished through chemical, physical and biological methods, but the excessive and continuous use of chemical products, may result in selection of resistant micro-organisms, in addition, many fungicides have a high toxicity and its indiscriminate use can cause undesirable effects on other organisms in the environment. The objective of this study is to explore the biological and chemical potential of secondary metabolites produced by plants of the Solanaceae family with potential fungitoxic the pathogens. We selected 15 species of Solanaceae plants that had the extracts of its leaves evaluated in vitro biological assays on the mycelial growth of 6 plant pathogens of importance in agriculture. Among these, three were selected for further investigation, the species Solanum americanum, Physalis peruviana and Acnistus arborescens. In the study of plant S. americanum, it was identified bioactive compounds belonging to the class of glycoalkaloids that inhibited the mycelial growth of the pathogen M. perniciosa. In the study of A. arborescens it was identified the presence of the active compound belonging to the class of withanolides, probably the 7β-acetoxywithanolide D, and its antifungal activity is being reported for the first time. In the study of plant P. peruviana semipure bioactive fraction indicated the presence of the compound belonging to the class of withanolides. These results showed that the compounds present in plants, have bioactivity that inhibit the mycelial growth of pathogenic fungi M. perniciosa and P. cinnamomi and may be a new option in the adjuvant control pathogens.
Fradinho, Patrícia Catarina das Neves Bordalo Branco. "Gluten-free fresh pasta enriched with bioactive compounds." Doctoral thesis, ISA, 2020. http://hdl.handle.net/10400.5/21203.
Повний текст джерелаSustainability of the agri-food chain is on today’s agenda, whether through the use of industrial byproducts or the investigation of alternative sources of ingredients. The increasing number of individuals with gluten-related diseases, but also consumers following a gluten-free diet are the drivers for the continually growing number of gluten-free products launched in the market. However, in addition to their still limited commercial availability and high price compared to their wheat counterparts, gluten-free products show nutritional deficiencies. Following the current consumer trends for healthy foods with underlying sustainable principles (ingredients and processes), this thesis aimed the development of a gluten-free fresh pasta based on rice flour from broken grains and Psyllium husk, enriched with Arthrospira platensis, Laminaria ochroleuca and potato peel. Firstly, the gelatinisation (5 – 26%) of rice flour from broken rice (rice processing industry by-product) was performed to assess the optimum conditions for producing gluten-free pasta. Afterwards, the pasta formulation (50% gelatinised rice flour/rice flour) was successfully optimized, and its structure reinforced with 4% Psyllium husk gel. This gluten-free pasta was then enriched with bioactive compound sources (Arthrospira platensis, Laminaria ochroleuca and potato peel) incorporated as lyophilised biomass, gel or liquid extract obtained by subcritical water extraction (autohydrolysis), an eco-friendly technology. The pastas developed were characterized in terms of cooking quality parameters, texture, colour, rheology, nutritional composition, antioxidant activity, in vitro digestibility and sensory analysis. It was found that autohydrolysis was a suitable technology for the valorisation of distinct materials, namely marine and industrial. Pastas with Laminaria ochroleuca provided a high mineral and fibre contents, and low-fat content, so that could bear nutritional claims. On the other hand, Arthrospira platensis incorporation proved to have a positive effect on the pasta antioxidant activity and overall sensory analysis without affecting the in vitro digestibility. Pasta with potato peel extract presented a high total phenolic content and antioxidant activity. All formulations presented good overall cooking quality and texture and rheology properties
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Borisova, Ralitsa Bogomilova. "Isolation of a Rhodococcus Soil Bacterium that Produces a Strong Antibacterial Compound." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1388.
Повний текст джерелаYan, Luping. "Bioactive marine natural products : analogue synthesis, SAR, and target identification." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50069.
Повний текст джерелаScience, Faculty of
Chemistry, Department of
Graduate
Forestieri, Roberto. "Isolation, structure elucidation, and total synthesis of bioactive natural products." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45668.
Повний текст джерелаAlmaliti, Jehad S. "Natural Products-Inspired Synthesis and Biological Evaluation of Bioactive Agents." University of Toledo Health Science Campus / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=mco1384555204.
Повний текст джерелаWong, Wan Yee. "Solvothermal crystallization of organic compounds and natural products /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202006%20WONG.
Повний текст джерелаCowe, H. J. de L. "Molecular studies of natural products and related compounds." Thesis, Robert Gordon University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370758.
Повний текст джерелаBoot, Claudia M. "Marine-derived fungi : an effective source of novel bioactive natural products /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2007. http://uclibs.org/PID/11984.
Повний текст джерелаMontgomery, Laura Jane. "Investigations of the biosynthesis and biomimetic synthesis of bioactive natural products." Thesis, University of Warwick, 2008. http://wrap.warwick.ac.uk/4420/.
Повний текст джерелаStevens, Kiri. "Methodology for the synthesis of NP25302 and other bioactive natural products." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:ae18879e-d75e-4280-ba55-1ae08e64034f.
Повний текст джерелаBerger, John Michael. "Isolation, Characterization, and Synthesis of Bioactive Natural Products from Rainforest Flora." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/28086.
Повний текст джерелаPh. D.
Rapson, Trevor Douglas. "Bioactive 4-methoxypyrrolic natural products from two South African marine invertebrates." Thesis, Rhodes University, 2005. http://hdl.handle.net/10962/d1006766.
Повний текст джерелаPérez, Hemphill Catalina Francis [Verfasser]. "Bioactive fungal natural products from extremophilic endophytes / Catalina Francis Pérez Hemphill." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2017. http://d-nb.info/1125595418/34.
Повний текст джерелаHagos, Selam. "Chemical Investigation of Bioactive Marine Extracts." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7301.
Повний текст джерелаStout, Elizabeth Paige. "Discovery and synthesis of bioactive natural product probes from marine systems." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37301.
Повний текст джерелаProtti, Michele <1986>. "Hyphenated Approaches for the Analysis of Bioactive Natural Compounds in Complex Matrices." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7520/.
Повний текст джерелаAshour, Mohamed A. A. "Structure elucidation of bioactive marine natural products using modern methods of spectroscopy." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982523963.
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