The presented diploma thesis is focused on the study of composition and biological effects of some super-foods. Theoretical part deals with basic information about chosen superfoods and their bioactive substances. Further, theoretical part describes the overview of vesicular systems used for encapsulation and the most common methods of particle characterization. A brief review of cell cultures and cultivation of human cells is presented as well as methods for cytotoxicity a genotoxicity testing. In the experimental section, aqueous and ethanol extracts of super-foods were prepared. These extracts were then encapsulated into liposomal and combined PHB particles. Super-food extracts were characterized by spectrophotometrical methods in order to determine the content of polyphenols, flavonoids, anthocyanins, carotenes, chlorophyll, tannins, and antioxidant activity. The physico-chemical characteristics of prepared liposomal and combined particles were determined too. The particles with encapsulated extracts were further tested using the MTT assay and SOS chromotest to describe their potential cytotoxic and genotoxic effects.

Production and consumption of edible berries are increasing rapidly in the United States, mostly due to their superior flavor profile, and popular diet-related value with their human health relevant bioactives and nutritional benefits. However, bioactive and nutritional qualities, especially human health protective phenolic antioxidants and associated non-communicable chronic disease (NCD) relevant health benefits of berries vary widely among accessions/cultivars and due to different production practices (organic vs conventional). Therefore, the aim of this thesis was to screen and select high phenolic and high antioxidant serviceberry and blackberry accessions/cultivars and to investigate the effect of different weed management and fertilization (organic vs. conventional) practices on phenolic bioactive linked antioxidant and anti-diabetic properties of blackberry using in vitro assay models. Overall, high phenolic-bioactive linked antioxidant and anti-hyperglycemic properties were observed in both serviceberry and blackberry accessions/cultivars and further for blackberry it was significantly higher under organic weed management and fertilization practices.

Orientador: Ana Paula Girol / Resumo: A poluição do ar e o uso de cigarro são as principais fontes de inalação e exposição a agentes carcinógenos, como os hidrocarbonetos aromáticos policíclicos (HAP) resultantes da combustão incompleta de matéria orgânica e distribuídos amplamente no ambiente. O benzopireno é um dos principais HAP presentes no ambiente e com alta capacidade carcinogênica, sendo, portanto, usado em modelos experimentais in vivo. Investigações têm mostrado que os fármacos anti-inflamatórios podem reduzir a incidência de câncer de pulmão. Os compostos bioativos naturais (CBN) como os terpenos e flavonoides apresentam muitas propriedades, entre elas, redução da inflamação, estimulação do sistema imune e modulação de enzimas detoxificantes. Entre os CBNs destacamos a piperlongumina (PL), um alcaloide da Piper longum, que pode representar uma possibilidade de tratamento para o câncer de pulmão. Para o desenvolvimento do trabalho foram usados camundongos Balb/c divididos em 3 grupos (n=10/grupo): controle (sham), induzido por benzopireno (100 mg/kg, diluído em DMSO e administrado intraperitonealmente, i.p.) não tratado (BaP) e induzido por benzopireno e tratado com PL (2 mg/kg em DMSO a 10%, i.p.) a partir da oitava semana pós-indução (BaP/PL). Os animais foram pesados diariamente. A pletsmografia para verificação de volume, frequência e ventilação pulmonares foi realizada na última semana do protocolo (12ª semana). Após, os animais foram eutanasiados para coleta de sangue, lavado broncoalveolar e frag... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Orientador: Cassia Roberta Malacrida Mayer / Resumo: O Cerrado, segundo maior bioma brasileiro, possui uma rica flora e fauna dentre as savanas do mundo. O pequi (Caryocar brasiliense Camb.) é um fruto nativo desse bioma e apresenta muitos compostos bioativos como carotenoides, vitaminas A e E e compostos fenólicos que possuem ações anticarcinogênicas, antimicrobianas e antioxidantes. Esses compostos, no entanto, são sensíveis a exposição à luz e oxigênio. Para amenizar essa degradação podem ser utilizados métodos de encapsulação. A extração do óleo da polpa de pequi, por prensagem a frio, gera uma torta residual rica em compostos bioativos. Portanto, o objetivo do presente trabalho foi a encapsulação dos compostos fenólicos presentes na torta residual por meio da liofilização utilizando diferentes agentes encapsulantes (amido de mandioca modificado, goma arábica, maltodextrina e ovoalbumina). Para tanto foi obtido um extrato aquoso (1:6 m/v) da torta residual utilizando extração ultrassônica com os seguintes parâmetros: 240 W de potência, 50% de pulso e 10 minutos. Os materiais encapsulantes corresponderam a 20% do extrato. Inicialmente, o extrato foi misturado aos agentes encapsulantes puros com o intuito de verificar quais os melhores encapsulantes. Numa segunda etapa, foram utilizadas misturas de amido de mandioca modificado (AM) e maltodextrina (MD) para misturas nas proporções de 50% de AM e 50% de MD; 75% AM e 25% MD e 25% AM e 75% MD. Todas as amostras foram liofilizadas a -50 °C por 48 horas, originando pós de cor amar... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Cerrado, the second largest Brazilian biome, has a rich flora and fauna among the world’s savannas. Pequi (Caryocar Brasiliense Camb.) is a native fruit of this biome and has several bioactive compounds such as carotenoids, vitamins A and E and phenolic compounds that perform anticarcinogenic, antimicrobial and antioxidants actions. These compounds, however, are sensitive to light and oxygen exposure. To mitigate this degradation, encapsulation methods can be used. The oil extraction from pequi pulp, by cold pressing, generates a residual cake rich in bioactive compounds. Therefore, the objective of the present work was the encapsulation of the phenolic compounds present in the residual cake by freeze-drying using different encapsulating agents (modified cassava starch, Arabic gum, maltodextrin and ovoalbumin). For this, an aqueous extract (1:6 m/v) of the residual cake was obtained using ultrasonic extraction with the following parameters: 240 W of power, 50% of pulse and 10 minutes. The encapsulating materials corresponded to 20% of the extract. Initially, the extract was mixed with pure encapsulating in order to verify which are the best encapsulating. In second stage, modified cassava starch (AM) and maltodextrin (MD) were used for mixtures in the proportions of 50% AM and 50% MD; 75% AM and 25 MD and 25% AM and 75% MD. All samples were freezing drying at -50°C for 48 hours, resulting in yellowish powders, which were evaluated for physicochemical characteristics. Afte... (Complete abstract click electronic access below) / Mestre

Title: Bioactive interfaces between synthetic surfaces and biological fluids Author: Andrés de los Santos Pereira Institute: Institute of Macromolecular Chemistry, Czech Academy of Sciences Supervisor of the doctoral thesis: RNDr. Eduard Brynda, CSc., Institute of Macromolecular Chemistry, Czech Academy of Sciences Abstract: The application in medicine of label-free affinity biosensors, advanced implants, and blood-contacting devices requires that their surfaces resist non-specific protein adsorption (fouling) and associated complications in blood-derived fluids while displaying immobilized bioreceptors that provide specific biofunctionality. The aim of this thesis was to explore the strategies for the preparation of these antifouling bioactive surfaces. Various types of recently developed antifouling polymer brushes were synthesized and evaluated in terms of their ability to prevent fouling from blood plasma (obtained from various commercial sources and individual donors) as well as thrombus formation when contacted with whole blood. Moreover, single-cell force spectroscopy was utilized to characterize the bacterial adhesion force and energy on these polymer brushes, which were significantly reduced in comparison to various reference substrates. The immobilization of bioreceptors was tackled by means of a...

Philosophiae Doctor - PhD / The World Health Organisation predicts that by the year 2050, 10 million people could die annually as a result of infections caused by multidrug resistant bacteria. Individuals with compromised immune systems, caused by underlying disease such as HIV, MTB and COVID-19, are at a greater risk. Antibacterial resistance is a global concern that demands the discovery of novel drugs. Natural products, used since ancient times to treat diseases, are the most successful source of new drug candidates with bioactivities including antibiotic, antifungal, anticancer, antiviral, immunosuppressive, anti-inflammatory and biofilm inhibition. Marine bioprospecting has contributed significantly to the discovery of novel bioactive NPs with unique structures and biological activities, superior to that of compounds from terrestrial origin. Marine invertebrate symbionts are particularly promising sources of marine NPs as the competition between microorganisms associated with invertebrates for space and nutrients is the driving force behind the production of antibiotics, which also constitute pharmaceutically relevant natural products.

Philosophiae Doctor - PhD / bioassay guided isolation approach was then used to isolate the high molecular weight antibacterial compound (50kDa-100kDa) from T. actiniarum fermentations. With common protein isolation, purification and detection methods failing to provide insight into the nature of the antibacterial compound, we hypothesized that the active agent is not proteinaceous in nature and may be a high molecular weight exopolysaccharide. Extraction and antibacterial screening of the exopolysaccharide fraction from T. actiniarum showed antibacterial activity as well as lytic activity when subjected to a zymography assay using Pseudomonas putida whole cells as a substrate. Additionally, the biosynthetic pathways for the production of poly-β-1, 6-N-acetyl-glucosamine (PNAG), an exopolysaccharide involved in biofilm formation and chondroitin sulfate, a known and industrially important glycosaminoglycan with antibacterial and anti-inflammatory activity was identified and the mechanism may be novel. Genome mining identified a variety of novel secondary metabolite gene clusters which could potentially encode other novel bioactivities. Therefore a bioassay guided isolation, focused on the small (<3kDa) molecules, was pursued. Secondary metabolites were extracted, fractionated and screened for biofilm inhibition, antibacterial and anticancer activity and activity was observed in all assays. Active fractions were dereplicated by UHPLC-QToF-MS and compounds of interest were isolated using mass guided preparative HPLC. The purity of the isolated compounds was assessed using UHPLC-QToF-MS and NMR and the structure of the target compounds elucidated. Structures that could be determined were the bile acids cholic acid and 3-oxo cholic acid and although not responsible for the observed activities, this is the first report of bile acid production for this genus. This is the first study investigating the bioactive potential of the strain and the first demonstrating that T. actiniarum is a promising source of potentially novel pharmaceutically relevant natural products depicted through both culture-dependent and culture-independent approaches.

<p>  </p> <p>Edible insects, a novel source of protein, are gaining interest for their health promoting attributes. In this study, the <em>in vivo and in vitro</em> antioxidant effect of tropical banded cricket (<em>Gryllodes sigillatus</em>) peptides was evaluated. Antioxidant activity by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activity, oxygen radical antioxidant capacity (ORAC) and caco-2 cellular antioxidant activity, were measured in hydrolyzed followed by simulated gastrointestinal digested (SGD) cricket peptides. <em>In vivo</em> analysis was conducted using <em>Caenorhabditis elegans</em> as a model. <em>In vitro</em> analysis showed cricket peptides had greater (p< 0.05) antioxidant activity than the unhydrolyzed protein (control). In <em>C. elegans,</em> the lifespan of nematodes fed SGD peptides increased under chronic and acute oxidative stress conditions. Reactive oxygen species (ROS) levels of nematodes fed SGD peptides under paraquat induced oxidative stress were lower (p<0.05) than that of the control group. Further studies using polymerase chain reaction (PCR) indicated that the increased resistance to oxidative stress in <em>C. elegans</em> fed SGD peptides could be due to the increased expression of the stress-related gene gst-4. Taken together, these results indicate that tropical banded cricket peptides could be used as a functional food and nutraceutical to combat oxidative stress. </p>

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