Percorrer por autor "Sayer, Claudia"
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- Bioactive evaluation and application of different formulations of the natural colorant curcumin (E100) in a hydrophilic matrix (yogurt)Publication . Almeida, Heloísa H.S.; Barros, Lillian; Barreira, João C.M.; Calhelha, Ricardo C.; Heleno, Sandrina A.; Sayer, Claudia; Miranda, Cristiane Grella; Leimann, Fernanda Vitória; Barreiro, M.F.; Ferreira, Isabel C.F.R.Curcumin (E100) is a natural colorant that, besides conferring color, has bioactivity, serving as an alternative to some artificial colorants. As a hydrophobic colorant, its modification/compatibilization with the aqueous medium is required to improve stability and enable its application in hydrophilic food matrices. Herein, different formulations of curcumin (curcumin powder: PC, water-dispersible curcumin: DC: and nanoencapsulated curcumin: NC) were evaluated as yogurt colorants. PC showed the strongest bioactivity in all assays (EC50 values: 63±2 to 7.9±0.1 μg.mL-1; GI50 values: 48±1 to 17±1 μg.mL-1 and MIC values: 0.0625 to 0.5 mg.mL-1), which might indicate that DC and NC reduce the short-term accessibility to curcumin. The tested curcumin formulations produced yogurts with different appearance, specifically associated with their color parameters, besides presenting slight changes in nutritional composition and free sugars and fatty acids profiles. The water compatible formulations (DC and NC) showed advantages over hydrophobic (PC) having a wider industrial utilization.
- Encapsulation of clove oil in nanostructured lipid carriers from natural waxes: Preparation, characterization and in vitro evaluation of the cholinesterase enzymesPublication . Meneses, Alessandra Cristina de; Marques, Elisa Balbi Pinto; Leimann, Fernanda Vitória; Gonçalves, Odinei Hess; Ineu, Rafael P.; Araújo, Pedro Henrique Hermes de; Oliveira, Débora de; Sayer, ClaudiaEugenol is a phenolic compound largely found in the clove essential oil that possesses promising biological activity. However, its low water solubility is a major concern and encapsulation is an alternative to improve water affinity. The objective of this work was to produce nanostructured lipid carriers (NLC) by hot homogenization/ultrasound emulsification and to evaluate the effect of free and encapsulated clove oil on the in vitro cholinesterase enzymes modulation using Drosophila melanogaster (DM) tissue. The NLC composed of a natural wax (carnauba or beeswax) and crodamol showed an average diameter between 121 and 367 nm with good dispersion and colloidal stability. The spherical shape and solid character together with the semi-crystalline environment confirm the formation of NLC. DSC analysis indicated polymorphic transition events of the waxes. In vitro tests using DM demonstrated that free clove oil showed a good inhibition of the butyryl and acetylcholinesterase enzymes above a concentration of 10 mM, with IC50 values of 4.3 and 3.5 mM, respectively. The dispersions of the NLC loaded with clove oil showed a decrease in the IC50 enzymes values, indicating the preservation of the clove essential oil and suggesting an increased in the solubility. Results indicate that NLC dispersions have good potential to be used for foods and cosmetic aqueous formulations possessing biological activity.
- Evaluation of berberine nanoparticles as a strategy to modulate acetylcholinesterase activityPublication . Leimann, Fernanda Vitória; Souza, Luma Borges de; Oliveira, Byanca Pereira Moreira de; Rossi, Bruna Franzon; Silva, Patricia Sabino da; Shiraishi, Carlos Seiti Hurtado; Kaplum, Vanessa; Abreu, Rui M.V.; Pereira, Carla; Barros, Lillian; Peron, Ana Paula; Ineu, Rafael Porto; Oechsler, Bruno Francisco; Sayer, Claudia; Araujo, Pedro Henrique Hermes de; Gonçalves, Odinei Hess; Shiraishi, Carlos S.H.Researchers have concentrated efforts in the search for natural-based reversible inhibitors for cholinesterase enzymes as they may play a key role in the treatment of degenerative diseases. Diverse plant alkaloids can inhibit the action of acetylcholinesterase and, among them, berberine is a promising bioactive. However, berberine has poor water solubility and low bioavailability, which makes it difficult to use in treatment. The solid dispersion technique can improve the water affinity of hydrophobic substances, but berberine solid dispersions have not been extensively studied. Safety testing is also essential to ensure that the berberine-loaded solid dispersions are safe for use. This study investigated the effectiveness of berberine-loaded solid dispersions (SD) as inhibitors of acetylcholinesterase enzyme (AChE). Docking simulation was used to investigate the influence of berberine on AChE, and in vitro assays were conducted to confirm the enzymatic kinetics of AChE in the presence of berberine. Berberine SD also showed improved cytotoxic effects on tumoral cells when dispersed in aqueous media. In vivo assays using Allium cepa were implemented, and no cytotoxicity/genotoxicity was found for the berberine solid dispersion. These results suggest that berberine SD could be a significant step towards safe nanostructures for use in the treatment of neurodegenerative diseases.
- Progesterone-loaded solid lipid nanoparticles for use in the regulation of the estrous cycle in female ratsPublication . Fogolari, Odinei; Leimann, Fernanda Vitória; Ineu, Rafael Porto; Rudy, Marcia; Ludwig, André Franco; Salles, Fernando Marques; Amorim, João Paulo de Arruda; Franci, Celso Rodrigues; Sagae, Sara Cristina; Sayer, Claudia; Araújo, Pedro Henrique Hermes de; Gonçalves, Odinei HessProtocols used for artificial insemination involve the effective synchronization of the estrous cycle by the administration of exogenous hormones including progesterone analogs. Although widespread in the world, the current techniques present many disadvantages that need to be overcome such as the time dependency of progesterone levels in the blood and the need to remove the release dispositive. Nanotechnology may offer the tools for it, and solid lipid nanoparticles (SLN) are a promising candidate to be used as nanocarriers for progesterone. In this work, progesterone-loaded SLNs were investigated in the regulation of the estrous cycle in female rats. First, the obtention of the SLN was investigated to determine how experimental parameters may affect the encapsulation efficiency of progesterone and the morphology of the nanoparticles. Also, in vitro release profiles of progesterone were also evaluated. Sexual receptivity, mutagenicity, hepatic inflammation and steatosis, hormone measurement, and biometric parameters of pups were also determined. Progesterone-loaded SLN induced estrous cycle synchronization and were able to maintain the estrous phase of the estrous cycle while inducing a greater latency release for its onset. Progesterone induced an increase in the sexual receptivity of the females and did not alter the biometric parameters like the body weight of the mothers and puppies, until weaning. Results gathered here demonstrated that encapsulation of progesterone may be a promising alternative to the conventional methods for synchronization of the estrous cycle of female animals in artificial insemination procedures.