Characterization of k-carrageenan/Locust bean gumbased films with b-carotene emulsion

New bio-based materials have been exploited to develop biodegradable and edible films as an effort to extend shelf life and improve quality of food while reducing packaging waste. The objective of this study was to investigate physicochemical properties of k-carrageenan/locust bean gum (k-car/LBG) films with different bcarotene emulsion concentrations. To prepare oil-in-water emulsions, b-carotene (0.03% v/v) was dissolved in mediumchain triglycerides (MCTs), and the solution was mixed (1:9 v/v) with a pectin solution (3% w/v) as emulsifier. Film forming solutions were prepared by adding b-carotene emulsion (0-3% w/w) into the k-car/LBG solution (40/60% w/w) with 0.3% (w/v) of glycerol. Films with different b-carotene concentrations were characterized in terms of optical, mechanical and barrier properties and compared with control films without bcarotene. The results suggested that mechanical, physical and barrier properties of k-car/LBG films were influenced by the presence of b-carotene. Results showed that addition of b-carotene to the k-car/LBG films studied resulted in significant decrease (p<0.05) in water vapour transmission rate values. Film opacity values (ranging from 4.9 to 12.5 %) increased when b-carotene was incorporated to the film. Therefore, b-carotene emulsions have potential to be used as a natural additive on kcar/LBG films, particularly in the food packaging industry

The molecular basis of host specialization in bean pathovars of Pseudomonas syringae

Biotrophic phytopathogens are typically limited to their adapted host range. In recent decades, investigations have teased apart the general molecular basis of intraspecific variation for innate immunity of plants, typically involving receptor proteins that enable perception of pathogen-associated molecular patterns or avirulence elicitors from the pathogen as triggers for defense induction. However, general consensus concerning evolutionary and molecular factors that alter host range across closely related phytopathogen isolates has been more elusive. Here, through genome comparisons and genetic manipulations, we investigate the underlying mechanisms that structure host range across closely related strains of Pseudomonas syringae isolated from different legume hosts. Although type III secretionindependent virulence factors are conserved across these three strains, we find that the presence of two genes encoding type III effectors (hopC1 and hopM1) and the absence of another (avrB2) potentially contribute to host range differences between pathovars glycinea and phaseolicola. These findings reinforce the idea that a complex genetic basis underlies host range evolution in plant pathogens. This complexity is present even in host–microbe interactions featuring relatively little divergence among both hosts and their adapted pathogens

Structural characterization and release profile of omega-3 fatty-acids encapsulated in nanoemulsions

Omega-3 (-3) fatty-acids are functional compounds with various benefits such as reduction of cardiovascular diseases. However, these fatty acids degrade quickly, present low water solubility and an unpleasant aroma, which make essential their encapsulation. The encapsulation (e.g. nanoemulsion production) process can change structural properties, which can affect the behavior of the system when applied to food matrices and within the gastrointestinal tract. The objective of this work was to characterize oil-in-water bio-based nanoemulsions with -3 using lactoferrin as a natural emulsifier, when submitted to different drying processes. Nanoemulsions were produced using high-pressure homogenization (5 cycles, 20,000 psi) using 2 % (w/w) lactoferrin and 5 % (w/w) -3. Nanoemulsions were dried by nanospray-drying (Nano Spray dryer B-90HP, Buchi) and freeze-drying methods. Physical and morphological properties were evaluated using dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. Circular dichroism (CD) and FTIR-ATR were used to assess possible structural and chemical changes after dry treatments. Moreover, -3 release profile was studied in ethanol (20 % and 50 % (v/v)) at 25 ºC (simulation of food matrices) and at pH 7.4 and pH 2 at 37 ºC (simulation of different gastrointestinal phases). DLS results showed that original size (170 nm) and zeta-potential (+30 mV) of nanoemulsions was not achieved after nanospray-drying process probably caused by protein agglomeration. CD and FTIR-ATR results revealed lactoferrin structural modifications after drying processes as well as a reduction of -helix and -sheet content, being this effect more evident on nanospray-drying samples. FTIR-ATR results showed shifts of the amide I and amide II bands in both drying processes samples. At 20 % ethanol, -3 began to release after 48h which could allow nanoemulsions incorporation in food products such as ice cream and mayonnaise. This work provides useful information to design nanoemulsions aiming lipophilic compound encapsulation for food applications.info:eu-repo/semantics/publishedVersio

Using the ‘regime shift' concept in addressing social-ecological change : Social-ecological regime shifts

‘Regime shift’ has emerged as a key concept in the environmental sciences. The concept has roots in complexity science and its ecological applications, and is increasingly applied to intertwined social and ecological phenomena. Yet what exactly is a regime shift? We explore this question at three nested levels. First, we propose a broad, contingent, multi-perspective epistemological basis for the concept, seeking to build bridges between its complexity theory origins and critiques from science studies, political ecology, and environmental history. Second, we define the concept in a way that is consistent with this epistemology, building on previous work on speed, scale, stickiness, and interrelationships, but also emphasising human perceptions and rhetorical uses of the notion. Third, we propose a novel typology of the ways in which the regime shift concept is used in analysing social–environmental phenomena in geography and beyond. These uses are categorised along two axes. On the one side, we distinguish between description of past or present changes and normative prescriptions for the future. On the other side, we distinguish between whether the focus is on material shifts (social and ecological) or conceptual shifts (discourses and ideas). We illustrate the typology with reference to social–environmental changes in landscapes around the world that are dominated by plantations or the widespread naturalisation of Australian Acacia species. We conclude that the regime shift concept is a boundary object with value as both an analytical and communicative tool in addressing social–environmental challenges

Banana starch nanocomposite with cellulose nanofibers isolated from banana peel by enzymatic treatment: In vitro cytotoxicity assessment

The potential use of cellulose nanofibers (CNFs) as a reinforcing agent in banana starch-based nanocomposite films was investigated. CNFs were isolated from banana peel (Musa paradisiaca) by enzymatic hydrolysis. Banana starch-based nanocomposite films were prepared with CNFs using the casting method. CNFs effect on cell viability and on nanocomposite films properties was investigated. The cytotoxicity of CNFs was assessed on Caco-2 cell line. CNFs were not cytotoxic at 502000??g/mL. However, CNFs above 2000??g/mL significantly decreased cell viability. Topography analysis showed that the incorporation of CNFs modified the film structure. The nanocomposites exhibited a complex structure due to strong interactions between CNFs and starch matrix, promoting a remarkable improvement on mechanical and water barrier properties, opacity and UV light barrier compared to the control film. CNFs can offer a great potential as reinforcing material for starch-based nanocomposite films, producing a value-added food packaging from a waste material.The authors would like to acknowledge the financial support provided by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) (140274/2014-6), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) (2952/2011) and CAPES/FCT número349/13 for Ph.D internship program. Joana T. Martins acknowledges the Foundation for Science and Technology (FCT) for her fellowship (SFRH/BPD/89992/2012). This study was supported by 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. The authors would also like to acknowledge the Brazilian Nanotechnology National Laboratory (LNNano) for allocation of the TEM, AFM and AFM-Nano IR apparatus.info:eu-repo/semantics/publishedVersio

Integrating ecosystem services and disservices: insights from plant invasions

There is growing interest in ecosystem disservices, i.e. the negative effects of ecosystems on humans. The focus on disservices has been controversial because of the lack of clarity on how to disentangle ecosystem services and disservices related to human wellbeing. A perspective that considers both services and disservices is needed to inform objective decision-making. We propose a comprehensive typology of ecosystem disservices, and present a framework for integrating ecosystem services and disservices for human wellbeing linked to ecosystem functioning. Our treatment is underpinned by three key assumptions: (1) ecosystem attributes and functions are value-free; (2) the perception of benefits or nuisances are however dependent on societal context, and preferences and actions by societal actors may trigger, enhance or alleviate benefits or nuisances derived from ecosystems; and (3) the notion of disservices must account for the role of human management in assessments of ecosystem values, i.e. the social and technological measures that identify, protect, promote or restore desirable levels of services, and concurrently minimise, mitigate or adapt to disservices. We illustrate our ideas with examples from plant invasions as a complex social-ecological phenomenon

Science communication in bioengineering and biotechnology: Active and collaborative learning project

In a society increasingly dependent on science and technology, the need to equip our students with the most varied digital and communication skills is crucial. Active and collaborative learning among peers is essential for the acquisition of transversal skills. Communication is one of the main tools that the Engineer uses to reach his target audience. Science Communication in Bioengineering and Biotechnology (CCBioTec) is a project on Innovation and Development of Teaching and Learning supported by Center IDEA-UMinho, a structure that emerges to promote and value Innovation and Development of Teaching and Learning at the University of Minho. CCBioTec is transversal to a set of Learning Units (LU) under the responsibility of the Department of Biological Engineering (DEB), including one LU of each year of the Integrated Masters in Biological Engineering and in Biomedical Engineering. The main goals of CCBioTEc are: to foster the awareness of the DEB educational community on the importance of science communication, as well as to develop science communication skills, through the production of short videos (pitches) displaying the explanation, in a simple and dynamic way, of complex concepts of Bioengineering and Biotechnology related with the curricula of each LU. CCBioTec started in the second semester of 2020/21, and it will go on in the 1st semester of 2021/22. The project was designed to be implemented according to the following steps: 1 - Technical and pedagogical training of teachers; 2 - Technical training of students involved in the project - Week CCBioTEC-2021; 3 - Development of materials for Science Communication in Bioengineering and Biotechnology; 4 - CCBioTec-2021 competition. In CCBioTec, teachers presenting himself as a mediator/facilitator of learning, boosting students development of transversal skills, collaborative work, decision making and the expression of ideas, together with the acquisition of knowledge foreseen in the curricular contents of the LU.(undefined)info:eu-repo/semantics/publishedVersio

Trends in legal and illegal trade of wild birds: a global assessment based on expert knowledge

Wildlife trade is a profitable economic activity. Birds are among the most heavily traded animals worldwide, with numerous species threatened by pet trade. Information on both legal and illegal aspects of trade and consumer demand is difficult to obtain across different countries, particularly given substantial socio-economic and cultural variation. Focusing on consumer demand in each country, we conducted a global survey among 105 international experts on bird conservation to identify expected trends, drivers and market characteristics of legal and illegal wild-caught pet bird trade. Our results suggest that future trends in legal bird trade will be mostly driven by socio-cultural motivations and intentional demand for wild-caught, rather than captive-bred birds. Bird popularity and rarity are the main factors expected to influence the choice of which bird species will be the most traded legally. Percentage of rural population was the main national-level socio-economic predictor for legal bird trade in the future. Demand for future illegal trade is expected to be driven by bird popularity and particular species identity. Experts consider illegal trade to be sustained mainly by consumers from higher socio-economic and educational backgrounds. Human population growth rate was the main national-level socio-economic predictor of illegal trade expected for the future. Legislation enforcement remains a critical issue in wildlife trade. Expanding trade networks and socio-economic changes continue to incorporate new regions into the wildlife trade. Investigating the multidimensional and synergistic determinants of wildlife trade will thus help address potential detrimental impacts bird trade might cause on biodiversity.This research was funded by FEDER Funds through the Operational Competitiveness Factors Program “COMPETE”, and by national funds through the Foundation for Science and Technology (FCT) within the framework of project “PTDC/AAG-GLO/0463/2014-POCI-01-0145-FEDER-016583”. A.N. acknowledges the support of the Darwin Initiative. J.R. acknowledges the support from FCT through Grant ICETA 2017-38 within project “PTDC/AAG-GLO/0463/2014-POCI-01-0145-FEDER-016583”. L.R. and C.C. acknowledge support from the FCT through Grants SFRH/BPD/93079/2013 and SFRH/BPD/84422/2012, respectively

Peripheral axonal ensheathment is regulated by RalA GTPase and the exocyst complex

Funding This work was supported by H2020 Marie Skłodowska-Curie Actions [H2020- GA661543-Neuronal Trafficking to R.O.T.], Fundo Regional para a Ciência e Tecnologia [IF/00392/2013/CP1192/CT0002 to R.O.T.] and iNOVA4Health (UID/Multi/04462/2013) (co-funded by FCT-FEDER-PT2020).Axon ensheathment is fundamental for fast impulse conduction and the normal physiological functioning of the nervous system. Defects in axonal insulation lead to debilitating conditions, but, despite its importance, the molecular players responsible are poorly defined. Here, we identify RalA GTPase as a key player in axon ensheathment in Drosophila larval peripheral nerves. We demonstrate through genetic analysis that RalA action through the exocyst complex is required in wrapping glial cells to regulate their growth and development. We suggest that the RalA-exocyst pathway controls the targeting of secretory vesicles for membrane growth or for the secretion of a wrapping glia-derived factor that itself regulates growth. In summary, our findings provide a new molecular understanding of the process by which axons are ensheathed in vivo, a process that is crucial for normal neuronal function.publishersversionpublishe