Percorrer por autor "Leimann, Fernanda Vitória"
A mostrar 1 - 10 de 57
Resultados por página
Opções de ordenação
- Active packaging to prevent lipid oxidation on Brazil nuts (Bertholletia excelsa HBK) stored under varying temperaturesPublication . Leme, Camila M.M.; Carvalho, Amarilis Santos; Rodrigues, Vanessa de Carvalho; Santos, Adriele Rodrigues de; Tanamati, Ailey Aparecida Coelho; Gonçalves, Odinei Hess; Valderrama, Patrícia; Leimann, Fernanda VitóriaBrazil nuts are largely consumed either as a whole or as an ingredient in different food products. These seeds are rich in lipids that are susceptible to oxidation, which is the most common cause of deterioration in their sensory and nutritional quality. Active food packagings are a potential strategy to prevent food lipid oxidation. In this work, thermoplastic starch/poly (butylene adipate-co-terephthalate) (TPS/PBAT) containing water-soluble curcumin and pinhao (Araucaria angustifolia) extract as natural antioxidants were used to package Brazil nuts (Bertholletia excelsa). Packaged nuts were stored under different temperatures and analysed for up to 30 days of storage. The lipid profile of the oil extracted from the nuts before packaging showed that it is rich in unsaturated fatty acids. The UV-Vis spectra were organized into an augmented matrix and then into a principal component analysis (PCA). Results showed that for 10 & DEG;C, the control TPS/PBAT film and the film containing pinhao extract resulted in the best preservation. When evaluated at 25 & DEG;C, the nuts packed in films that contained water-soluble curcumin presented the best oxidative stability until the 15th day of storage. After this period, the oxidation reactions were significant for all samples, indicating a possible compromise on the sensory and nutritional quality of Brazil nuts.
- Análise de componentes principais aplicada ao estudo da oxipropilação do resíduo da semente da Araucaria angustifóliaPublication . Rezende, Stephany; Pinto, João A.; Fernandes, Isabel P.; Leimann, Fernanda Vitória; Barreiro, M.F.A casca do pinhão brasileiro é um resíduo lenhocelulósico da semente da Araucaria angustifólia, uma espécie de conífera nativa da América do Sul. Esta semente é consumida após sofrer um processo de descasque, resultando na produção de uma quantidade significativa de resíduo sem valor comercial. Tendo por objetivo o desenvolvimento de aplicações para a valorização da casca do pinhão (PFS), este trabalho foca a produção de biopolióis a partir desta fonte lenhocelulósica através do processo de oxipropilação. O trabalho compreendeu o estudo da relação entre as variáveis do processo e as propriedades dos biopoliois, utilizando a metodologia de Análise de Componentes Principais (ACP). No que respeita à oxipropilação, selecionaram-se três razões PFS/óxido de propileno (PO) (30/70, 20/80 e 10/90; m/v). Testaram-se ainda quatro níveis de catalisador: 5, 10, 15 e 20%, (m/m, base biomassa). A oxipropilação ocorreu em condições moderadas de temperatura, pressão e tempo, resultando na produção de poliois líquidos. Numa segunda etapa, procedeu-se à caracterização dos biopoliois, no que respeita ao teor de homopolímero (POO), teor de grupos hidroxilo (IOH), viscosidade (V) e biomassa por reagir (UR) no biopoliol. Posteriormente, através da Análise de Componentes Principais, efetuou-se a avaliação das interações estabelecidas entre as variáveis do processo de oxipropilação e as propriedades dos poliois obtidos. A análise de ACP (Fig. 1) clarificou as interações estabelecidas, provando ser uma ferramenta útil para descrever e visualizar o processo de oxipropilação, com possibilidade de ser estendida a outros tipos de biomassa ou integrando diferentes variáveis de entrada.
- Analytical validation of an ultraviolet–visible procedure for determining vitamin D3 in vitamin D3-loaded microparticles and toxigenetic studies for incorporation into foodPublication . Silva, Tamires Barlati Vieira; Oliveira, Anielle; Moreira, Thaysa Fernandes Moya; Silva, Kelly Cristina; Zanin, Rodolfo Campos; Bona, Evandro; Gonçalves, Odinei Hess; Shirai, Marianne Ayumi; Peron, Ana Paula; Leimann, Fernanda VitóriaVitamin D is a water-insoluble compound presented in two main forms (D2 and D3), susceptible to environmental conditions. Microencapsulation is an alternative to supplements and preserve vitamin D properties in foods. Entrapment efficiency (EE) is the main property to evaluate the encapsulation effectiveness and therefore it is of interest the study of analytical methods for the identification and quantification of this compound within the particle. This paper describes a low cost UV–Vis methodology validation to the identification and quantification of vitamin D3 in microparticles produced by hot homogenization. The method was validated following the International Conference on Harmonization (ICH) guidelines. To guarantee safe application in foodstuff, microparticles toxigenicity was evaluated with Allium cepa L. in vivo model, showing no cytotoxic nor genotoxic potential. High entrapment efficiency was obtained, the results also demonstrated that the concentration of vitamin D3 in microparticles can be safely accessed by the validated method.
- Antibacterial efficacy of Enterococcus microencapsulated bacteriocin on Listeria monocytogenes, Listeria innocua and Listeria ivanoviPublication . Ramalho, Regiane; Souza, Nathália A.A. de; Moreira, Thaysa Fernandes Moya; Oliveira, Anielle; Perini, Hugo Felix; Furlaneto, Márcia Cristina; Leimann, Fernanda Vitória; Furlaneto-Maia, LucianaThis study focused on the microencapsulation of enterocin from Enterococcus durans (E. durans MF5) in whey powder (WP) using a spray-drying technique followed by the evaluation of how complexation can preserve the enterocin structure and antimicrobial activity against foodborne pathogens. Crude enterocin samples (1 and 5%) were microencapsulated in 10% WP. The antimicrobial activity of unencapsulated (crude) enterocin and microencapsulated enterocin was tested against the target bacteria Salmonella Typhimurium, Escherichia coli, Listeria monocytogenes, Listeria innocua, and Listeria ivanovi. The microencapsulation yields were 31.66% and 34.16% for concentrations of 1 and 5% enterocin, respectively. There was no significant difference between these concentrations. Microencapsulated enterocin was efficient for up to 12 h of cocultivation with Listeria sp., and the concentration required to inhibit the growth of target bacteria presented values of 6400 AU/ mL (arbitrary unit). Microencapsulated enterocin demonstrated enhanced efficacy against Listeria species and E. coli when compared with crude enterocin (p < 0.05). Fourier transform-infrared spectroscopy and differential scanning calorimetry results confirmed the presence of enterocin in the microparticles. Scanning electron microscopy showed cell damage of the target bacteria. The results showed that complexation with WP preserved enterocin antimicrobial activity during spray-drying, indicating its potential use as a food preservative.
- Antiinflammatory activity of carnauba wax microparticles containing curcuminPublication . Rocha, Bruno Ambrósio da; Francisco, Cristhian Rafael Lopes; Almeida, Mariana; Ames, Franciele Queiroz; Bona, Evandro; Leimann, Fernanda Vitória; Gonçalves, Odinei Hess; Bersani-Amado, Ciomar AparecidaThe pharmacokinetic of curcumin has posed a challenge to its therapeutic efficacy. Drug encapsulation systems, particularly microparticles, are promising due to their ability to protect compounds against both physical and chemical degradation and to improve their bioactivity. The aim of the present study was to prepare curcumin loaded solid lipid microparticles from carnauba wax and evaluate its antiinflammatory efficacy. Microparticles were obtained by hot homogenization technique and characterized by scanning electron microscopy, differential scanning calorimetry, infrared spectroscopy and X-ray diffraction demonstrating the effective encapsulation of curcumin. Antiinflammatory efficacy was evaluated comparing free curcumin and curcumin encapsulated by carrageenan-induced paw edema in rats. Additionally, myeloperoxidase (MPO) activity and concentration of nitric oxide (NO) were evaluated in plantar tissue of rats. Microparticles showed regular and spherical morphology with 20 μm diameter. Thermal, spectroscopic, X-ray and images analysis demonstrated the encapsulation of curcumin in the lipid matrix. The evaluation of antiinflammatory activity showed that encapsulated curcumin at doses of 25 and 50 mg kg 1 were more effective than free curcumin at lower doses of 25 and 50 mg. kg 1 and had similar efficacy to free curcumin at dose a 400 mg.kg 1 , inhibiting the development of edema, myeloperoxidase (MPO) activity, and the increase in nitric oxide (NO) levels. Overall, curcumin microparticles were obtained with high encapsulation efficiency and antiinflammatory efficacy 16-fold better than free curcumin.
- Antioxidants extraction from Pinhão (Araucaria angustifolia (Bertol.) Kuntze) coats and application to zein filmsPublication . Freitas, Tânia Barbedo de; Santos, Carlos Henrique Koslinski; Silva, Marcos Vieira da; Shirai, Marianne Ayumi; Dias, Maria Inês; Barros, Lillian; Barreiro, M.F.; Ferreira, Isabel C.F.R.; Gonçalves, Odinei Hess; Leimann, Fernanda VitóriaSeeds from Araucaria angustifolia (Bertol.) Kuntze are consumed after cooking and their coats discarded. Both coats and the cooking water present phenolic compounds, which may be used to improve mechanical properties and provide antioxidant characteristics to films. The objective of this work was to obtain and pinhão coat extracts and to apply these polyphenolic-rich extracts in zein films. Phenolic compounds composition, extraction yield and antioxidant activity (DPPH, ABTS and FRAP) of the extracts were determined. The most abundant molecules present in the hydroethanolic extract were (+)-catechin and an (epi)catechin dimer, whereas protocatechuic acid were predominant in the both cooking water and ethanolic extracts. Glass transition temperature of zein was not found in the extract-loaded films. Morphological changes were also caused by the presence of the extracts yielding smoother surfaces. The extracts added to zein films led to a three-fold increase in tensile strength (from 5.80 MPa to 17.65 MPa) and two-fold increase in the elongation at break (from 1.60% to 3.18%).
- Araucaria angustifolia (Bertol.) Kuntze extract as a source of phenolic compounds in TPS/PBAT active filmsPublication . Silva, Tamires Barlati Vieira; Moreira, Thaysa Fernandes Moya; Oliveira, Anielle; Bilck, Ana Paula; Gonçalves, Odinei Hess; Ferreira, Isabel C.F.R.; Barros, Lillian; Barreiro, M.F.; Yamashita, Fabio; Shirai, Marianne Ayumi; Leimann, Fernanda VitóriaThere is growing interest in the development of biodegradable packaging materials containing natural antioxidant extracts. In this sense, the use of extracts obtained from agro-industrial byproducts has proved to be a sustainable alternative. In this study, Pinhão extract, a byproduct of Pinhão (Araucaria angustifolia (Bertol.) Kuntze) seed consumption, was characterized by HPLC-DAD-ESI/MSn, demonstrating the presence of eight phenolic compounds, (+)-catechin and (−)-epicatechin being the most abundant molecules. TPS/PBAT films containing Pinhão extract were produced by blown extrusion and their properties (tensile properties, thermal characteristics and microstructure) were evaluated in order to determine the effect of the presence of extracts. Results suggested that the interaction between the phenolic compounds of the extract and the polymeric matrix caused the reduction in the crystallinity degree, and an increase in the starch glass transition temperature. The presence of Araucaria angustifolia (Bertol.) Kuntze extract significantly (p < 0.05) affected the color and opacity of the film. Regarding water vapor permeation, no significant difference (p > 0.05) was detected. However, the water solubility and the contact angle with water (polar solvent) and diiodomethane (non-polar solvent) significantly changed due to the extract addition. Moreover, the Pinhão extract conferred significant antioxidant capacity to the TPS/PBAT films as determined by DPPH, suggesting that this material can be applied as an active packaging material.
- Avaliação da estabilidade da cor de curcumina encapsulada por análise de componentes principaisPublication . Leimann, Fernanda Vitória; Gonçalves, Odinei Hess; Bona, Evandro; Fernandes, Isabel P.; Ferreira, Isabel C.F.R.; Barreiro, M.F.Alternativas aos corantes alimentares sintéticos estão disponíveis a partir de fontes vegetais, como a curcumina, que pode ser extraída da Curcuma longa L e possui reconhecida bioatividade. No entanto, a curcumina é termicamente instável e degrada rapidamente durante o aquecimento, o que constitui um desafio para o seu uso em alimentos sujeitos a processamento por calor. Neste estudo, a nanoencapsulação da curcumina em polímeros biocompatíveis, como a k-carragena, poli(álcool vinílico) (PVA) e poli(vinil pirrolidona) (PVP), utilizando a técnica de dispersão sólida seguida de spray drying foi aplicada aproveitando os efeitos protetores do encapsulamento. Avaliaram-se o efeito do pH do meio durante a obtenção das partículas, e os percentuais de curcumina e surfactante (Tween 80) (estes relativos à massa de polímero). Uma análise de componentes principais (PCA) foi realizada para identificar as condições experimentais que levariam à melhoria da estabilidade da cor da curcumina quando submetida a processos de aquecimento. Os resultados indicaram que os polímeros protegeram de forma diferente a cor durante o período de aquecimento (180°C por 30, 60 e 120 min). Para tempos menores de aquecimento (30 min) o PVA foi o encapsulante que melhor protegeu a cor, seguido da k-carragena que protegeu a cor de forma mais efetiva para 60 min de exposição e o PVP que manteve a cor estável pelo maior período de tempo de exposição (120 min). A curcumina não encapsulada foi avaliada como controle sendo observada perda completa da sua coloração após 30 min de tratamento térmico.
- Bio-residues of Ilex paraguariensis a. St. Hil. as a source of phenolic compounds with preservative potentialPublication . Pereira, Eliana; Menezes, Barbara de Sena Nunes; Caleja, Cristina; Pires, Tânia C.S.; Taofiq, Oludemi; Calhelha, Ricardo C.; Pinela, José; Soković, Marina; Leimann, Fernanda Vitória; Ferreira, Isabel C.F.R.; Barros, LillianThe use of agro-industrial wastes translates into an advantageous opportunity for the development of by-products [1]. Ilex paraguariensis A. ST. HIL. (yerba mate) is a tree widely cultivated and appreciated with a chemical composition that identifies several beneficial properties to the human body [2]. In this work, a comparison between the extracts of dehydrated yerba mate (EMNP) and bio-waste (EMP) leaves from the yerba mate industry in Brazil was made, as well as the incorporation of the EMP extract in a traditional food product, to evaluate its preservative potential. The individual profile of phenolic compounds was determined by HPLC-DAD-ESI/MS and the bioactive potential was assessed through in vitro tests for antioxidant, anti-inflammatory and antimicrobial activity, as well as cytotoxicity tests, in human tumor cell lines and in a non-tumor cell line. Among the seven phenolic compounds identified, four were found in greater quantity in the extracts of bio-residues of yerba mate (EMP). Regarding the functional properties, the extracts obtained revealed a high antimicrobial potential against the tested strains, as well as a very promising antioxidant and anti-inflammatory activities, without toxicity. After incorporating the most promising extract, EMP, in pancakes, the centesimal evaluation and the chemical composition (individual profile of sugars and fatty acids) revealed that after storage for 3 days the natural ingredient proved to show preservative efficiency. This study intended to develop new solutions that allow reduced application of artificial additives in food products.
- 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.