Development and characterization of edible films from polysaccharides of different sources

GLUPOR 12 - 12nd International Meeting of the Portuguese Carbohydrate Chemistry GroupEdible packaging experienced a notable growth in recent years and an important impact in the food industry. This growth is due to an increase in the interest, research and development of new packaging materials using natural polymers to replace the nonbiodegradable, synthetic materials used in synthetic packaging. Factors like the impact on sustainabi lity, the increased interest in renewable resources and biodegradable materials with no ecological impact on the environment are influencing the growth perspectives on the use of these materials [1]. [2]. Moreover, the use of edible materials opens the possibility of new and innovative applications of these packaging systems. In this work polysaccharides from different sources were tested in order to develop edible films to apply in food products in new innovative packaging systems. Methylcellulose (MC) of different grade (15 cPs and 1600 cPs of viscosity), carboxymethylcellulose (CMC) and potato starch films were used for the preparation of film forming solutions that were used for films' preparation (produced by casting). Mechanical properties, moisture, solubility, water vapor permeability (WVP), thickness, colour and opacity were evaluated for each film . Results showed that films present good optical properties with low opacity values. Potato starch-based films present values of 5.03 % ± 0.33 %, while for CMC the value obtained was 3.14 % ± 0.35 %. For MC of 15 cPs and 1600 cPs the obtained values were respectively, 4.07 % ± 1.50 % and 3.57 % ± 2.04 %. Regarding solubility the MC films were totally soluble in water while CMC films present a solubility of 58.46 % ± 1.29 %. Potato starch-based films presented the lowest solubility with values of 19.18 % ± 1.40 %. Mechanical properties results showed that the films of MC of 1600 cPs are flexible (elongation at break of 61 .35 % ± 8.80 %) and have the higher values of tensile strength (12.22 MPa ± 2.14 MPa). The films presenting higher vapor permeability were the ones produced using MC 15 cPs (7.31x10· 7 g(mhPa)"1 ± 3.73x1Q·8 g(mhPa)"1 ), whi le the potato starch-based films present a water vapour permeability of 3.78x10· 7 g(mhPa)"1 ± 3.79x1 0· 8 g(mhPa)"1 . Obtained results showed that polysaccharide-based fi lms based on cellulose derivate and starch present good properties to be used as edible packing in different food products, since that they are resistant and flexibles and present good optical properties.Acknowledgements: The project ESSENCE (reference POCl-01-0247-FEDER-010887) is co-funded by the Operational Program for Competitiveness and Internationalization (COMPETE 2020), under the Portugal 2020 partnership agreement, through the European Regional Development Fund (FEDER).info:eu-repo/semantics/publishedVersio

Carboxymethyl cellulose-based films: Effect of organosolv lignin incorporation on physicochemical and antioxidant properties

Organosolv lignin was incorporated in carboxymethyl cellulose (CMC)-based films as a reinforcing and bioactive agent. Films were produced by the casting method using compatible and environmentally friendly solvents. The incorporation of lignin in CMC-based films was evaluated in term of morphology, physicochemical, barrier, mechanical and antioxidant properties. Solubility tests showed that lignin improved the water resistance of the films for approx. 60%. This behavior was also observed for the water vapor permeability, achieving a 20% reduction. Morphological characteristics suggested low compatibility between organosolv lignin and CMC matrix, revealed by the small aggregates homogeneously distributed in the film, through scanning electron microscopy, related to the self-assembly behavior of lignin. CMC/lignin-based films also presented higher thermal stability. Fourier transform infrared spectroscopy showed that incorporation of lignin led to small changes in the film's structure. Finally, organosolv lignin proved to be a promising material for the development of active CMC-based films due to its demonstrated antioxidant activity that can be useful to pack food products that suffer from undesirable oxidation reactions.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Nanospraydryer for the production of sub-micro particles based on bovine lactoferrin

This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469 unit and COMPETE 2020 (POCI-01-0145- FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Arlete M. Marques (SFRH/BD/132911/2017) is the recipient of a fellowship from Fundação para a Ciência e Tecnologia (FCT, Portugal)info:eu-repo/semantics/publishedVersio

Physicochemical properties of alginate-based films: effect of ionic crosslinking and mannuronic and guluronic acid ratio

Abstract The use of alginates as films in food applications has increased in the recent years due to their swelling capacity and overall functionality. This behaviour is a result of their capacity to crosslink with Ca2+ ion. Aiming to fully understand the effect of calcium chloride (CaCl2) crosslinking and the mannuronic (M) and guluronic (G) acid ratio (M/G) of alginate structure in the films properties, alginate-based films with different (M/G) ratios were crosslinked at increasing CaCl2 concentrations. Films were produced by casting, and characterized in terms of mechanical properties (tensile strength and elongation-at-break), opacity, water sensitivity (moisture content, solubility and water vapour permeability) and morphology, evaluated by scanning electronic microscopy (SEM). Chemical interactions were studied by Fourier Transform Infrared Spectroscopy (FTIR) to assess possible chemical modifications of alginate-based films after crosslinking. Crosslinking significantly affected the alginate structure and properties, decreasing film thickness, moisture content, solubility and water vapour permeability of the alginate-based films. The mechanical properties were also influenced by the crosslinking and high CaCl2 concentrations lead to an increase of tensile strength. Results showed a relation between M/G ratios and CaCl2 concentrations and the resulting films properties. Alginate and the respective crosslinker should be chosen taking into account M/G ratio, since high contents of M residues lead to fragile and flexible films and high content of G residues to stronger films, and these properties are highly dependent on the concentration of CaCl2. Overall, alginate-based films are a good candidate to obtain tailored made edible films for food applications. Further investigation should be done to fully understand the effect of the alginate chain composition and order (e.g. MM, GG, GM, MG) in alginate-based films properties.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Maria José Costa is recipient of a fellowship supported by a doctoral program (SFRH/BD/122897/2016) funded by the Portuguese Foundation for Science and Technology (FCT, POPH-QREN and FSE Portugal). Sanna Sillankorva is Investigador FCT (IF/01413/2013). This research was supported by Norte Regional Operational Program 2014–2020 (Norte2020) through the European Regional Development Fund (ERDF) Nanotechnology based functional solutions (NORTE-01-0145-FEDER-000019).info:eu-repo/semantics/publishedVersio

Detrimental Effect Of Fungal 60-kda Heat Shock Protein On Experimental Paracoccidioides Brasiliensis Infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The genus Paracoccidioides comprises species of dimorphic fungi that cause paracocci-dioidomycosis (PCM), a systemic disease prevalent in Latin America. Here, we investigated whether administration of native 60-kDa heat shock protein of P. brasiliensis (nPbHsp60) or its recombinant counterpart (rPbHsp60) affected the course of experimental PCM. Mice were subcutaneously injected with nPbHsp60 or rPbHsp60 emulsified in complete's Freund Adjuvant (CFA) at three weeks after intravenous injection of P. brasiliensis yeasts. Infected control mice were injected with CFA or isotonic saline solution alone. Thirty days after the nPbHsp60 or rPbHsp60 administration, mice showed remarkably increased fungal load, tissue inflammation, and granulomas in the lungs, liver, and spleen compared with control mice. Further, rPbHsp60 treatment (i) decreased the known protective effect of CFA against PCM and (ii) increased the concentrations of IL-17, TNF-alpha, IL-12, IFN-gamma, IL-4, IL-10, and TGF-beta in the lungs. Together, our results indicated that PbHsp60 induced a harmful immune response, exacerbated inflammation, and promoted fungal dissemination. Therefore, we propose that PbHsp60 contributes to the fungal pathogenesis.119Fundacao de Amparo a Pesquisa do Estado de Sao Paulo [2009/14777-1, 2013/12278-3, 2009/03235-3, 2012/08552-0]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Resposta imune a doenças infecciosas

The interaction between pathogens and immune system occurs in a dynamic way with sophisticate mechanisms of evasion and immune control of infection, respectively. Therefore, it is a sine qua non condition to understand the complexity of this relationship in order to developed new strategies for infection control. Although the immune system has specialized mechanisms to control infection, different conditions involved in the interaction between immune system and pathogens can or cannot determine the development of disease. Interestingly, a protective immune response against one kind of parasite may not be protective against another. So, each pathogen presents a specific way of interaction with the immune system. The development of research in this area has contributed with a better comprehension of the immune system and pathogen relationship and opened perspective in improving the treatment with the development of new drugs and/or vaccines.A interação do sistema imune com os agentes infecciosos ocorre de uma maneira dinâmica, com mecanismos de controle da infecção e de escape sofisticados. A compreensão dessa complexidade é condição sine qua non para que se estabeleça uma ação total no controle dessas infecções. Embora a resposta imune desenvolvida para controle das diferentes infecções apresente certas particularidades, em geral, apresentam também mecanismos comuns. A priori os mecanismos podem ser redundantes, no entanto existe uma gama de sutilezas entre a interação hospedeiro-parasita que define o estabelecimento ou não de doença. Por outro lado, não se pode deixar de alertar que melhores condições de saneamento básico diminuiriam a incidência de inúmeras doenças. A classificação de uma resposta imune protetora tem que ser avaliada sempre em relação ao tipo de agente agressor, pois um mecanismo protetor conta um vírus pode não ser essencial contra uma bactéria extracelular. De qualquer forma, o avanço na pesquisa com diferentes patógenos tem contribuído para uma melhor compreensão da resposta imune decorrente da interação entre o hospedeiro e parasita o que pode resultar no desenvolvimento de novas drogas e vacinas

Efficacy of 25% diflubenzuron for control of Haematobia irritans (Diptera: Muscidae): in vitro and field challenges

Avaliou-se, neste experimento, a eficácia in vitro e in vivo do diflubenzuron a 25% para uso em bovinos, no controle da infestação por Haematobia irritans. Para o teste in vitro, ovos de moscas-dos-chifres foram mantidos em recipientes contendo fezes de animais não-tratados ou tratados com diflubenzuron a 25%, e acompanhados até emergência dos adultos. No teste in vivo, foram utilizadas 40 fêmeas aneloradas, divididas em dois grupos: controle (C) e tratado (T) com intensidade parasitária equivalente. Durante o experimento, o grupo C recebeu apenas suplementação mineral, enquanto o grupo T recebeu suplementação mineral e diflubenzuron a 25%. A contagem de moscas nos animais foi realizada na região dorsal, desde a nuca até as pontas da anca de cada animal, no início e ao final de um período de cinco meses. Na avaliação in vitro, o grupo controle apresentou média de emergência de 86% (± 8,4%), enquanto o grupo cultivado em fezes de bovinos tratados com diflubenzuron a 25% apresentou taxa de emergência média de 1% (± 0,2%), sendo a eficácia calculada de 98,83%. No teste in vivo, não foi observada redução significativa na contagem de moscas no grupo C, porém, no grupo T houve significativa redução da infestação por H. irritans (t = 16,46, p < 0,0001). A eficácia do produto, em condições de campo, foi de 99,20%. O diflubenzuron a 25% adicionado ao sal mineral mostrou-se eficaz contra H. irritans, sendo indicado para esse fim.In this experiment, the in vitro and in vivo efficacy of a 25% diflubenzuron commercial formulation were evaluated for control of Haematobia irritans infestation on cattle. For the in vitro test, horn-fly eggs were cultivated in feces from untreated or treated with 25% diflubenzuron for verification of adult emergence. In the in vivo test, 40 crossbred female bovines were divided into 2 experimental groups: Controls (C) and treated (T) with 25% diflubenzuron, with similar horn-fly infestations. In the in vitro test, the control group had a mean emergence of 86% (± 8.4%) while the group cultivated in feces from cattle treated with 25% diflubenzuron had a mean emergence rate of only 1% (± 0.2%), showing product efficacy of 98.83%. In the in vivo test no significant reduction was observed in the fly count of the C group, whereas the T group showed a clear reduction in the infestation (t = 16.46, p < 0.0001). The efficacy of the product under field conditions was 99.20%. In conclusion, the formulation of 25% diflubenzuron demonstrated efficacy against H. irritans, and is therefore indicated for this purpose