584 research outputs found
Mechanism of cellulase action in textile processes
The effects on fabric caused by cellulase enzymes always result from a process in which strong mechanical action affecting the fabric is provided. This paper discusses the interaction between cellulase activities and mechanical agitation during textile processes. Possible mechanisms are suggested for depilling and ageing effects accounting for the presence of mechanical factors. The paper includes a review of the mechanisms of indigo backstaining during cellulase washing. (C) 1998 Elsevier Science Ltd. All rights reserved
Laccase-catalysed protein-flavonoid conjugates for flax fibre modification
The introduction of flavonoid compounds into
proteins can improve the natural properties of proteins, being promising products which essentially require antioxidant property. The oxidative conjugation of protein–flavonoids
was processed by laccase catalysis resulting in the synthesis of biologically functional polymers. The new reaction products were detected in terms of sodium dodecyl sulfate polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionisation-time of flight mass spectra, showing a greater molecular weight formation. Their characterisations were
further carried out in terms of UV–Vis spectroscopy, photon correlation spectroscopy, differential scanning calorimetry and Fourier transform infrared (FT-IR) spectroscopy analysis. In addition, their application of protein–flavonoid conjugates
onto flax fibres was exploited to supplement a suitable microorganism environment of protein-possessed fibres. The anchoring of conjugates onto cationised fibres was successfully performed by ionic interaction with negatively charged
proteins. The level of anchoring efficiency was quantified in terms of measuring colour strength (k/s) and fluorescence microscopy analysis. The conjugates onto fibres presented acceptable durability in terms of washing resistance and the surface became hydrophilic when α-casein–catechin was
applied (lower contact angle 48°). By the anchoring of protein–flavonoid conjugates onto flax fibres, the final products with new colour generation and antioxidant activity
(>93%) were obtained
Liposomal formulations for rheumatoid arthritis
Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Rheumatoid arthritis (RA) is the most common inflammatory rheumatic disease, affecting almost 1% of the world population. Although the cause of RA remains unknown, the complex interaction between immune mediators (cytokines and effector cells) is responsible for the joint damage that begins at the synovial membrane. Activated macrophages are critical in the pathogenesis of RA and showed specifically express a receptor for the vitamin folic acid (FA), folate receptor β (FRβ). This particular receptor allows internalization of FA-coupled cargo. [...]info:eu-repo/semantics/publishedVersio
Foreword: Advances in Polymer/Fibre Biotechnology
[Excerpt] Biotechnology has been applied as a valuable tool to produce useful bio-based products from non-petrochemical renewable resources. Biologically produced polymers present advantages related with the biodegradability, performance, cheapness of substrate and defined structural variability. Beyond that, enzymes, the most proficient catalysts, continue to offer the most competitive processes compared with the chemical ones. Advances in protein engineering technology and the environmental and economic requirements contribute for the continuous search of acceptable biotechnologicalsolutionsfortheareas,including,polymerandtextile, medical,pharmaceutical, amongothers.Newtrendsandstrategieshavebeen highlighted in recent studies leading to significant advances in enzyme biocatalysis. The 9th International Conference on Fiber and Polymer Biotechnology 2016 (IFPB 2016) was held in September 2016 in Osaka Seikei College, Osaka, Japan. IFPB16 was a joint conference with Textile Biotechnology Symposia 2016 (TBS) and the 40th Annual Meeting of Advanced Fiber Materials Research Committee (AFMc). Previous events of IFPB had taken place at: University of Minho, Portugal (INTB 2000); University of Georgia, USA (INTB 2002); Graz University of Technology, Austria (INTB 2004); Korea Institute of Industrial Technology, Korea (INTB 2006); Jiangnan University, Wuxi, China(INTB 2007); University ofGent, Belgium (IPTB 2009), Stazione Sperimentale perla Seta, Milan, Italy(IPTB 2011) and University of Minho, Portugal (IPFB 2014). The main topics covered by IFTB 2016 comprised industrial enzymes, natural and bio-based polymers and fibers, biofunctionalization of synthetic materials, sustainable processes, smart materials through bio-catalysis and nano/bio-materials and applications. Richard Gross from the Department ofChemistry andChemicalBiology, Rensselaer Polytechnic Institute, USA, wasinvited askeynote speaker. His remarkablelecture about “Engineered Cutinases for Textile Polymer Surface Modification and Recycling” provided an excellent opportunity to learn more about the potentialities of cutinases as efficient catalysts. Gross highlighted his recent work related with cutinase redesign, its biophysical and biochemical characterization and ability to recycle polyethylene terephthalate (PET) and cellulose acetate (CA). Thomas Rosenau from University of Natural Resources and Life Sciences in Austria and Kanji Kajiwara from the Faculty of Textile Science and Technology of Shinshu University in Japan were the invited speakers and enriched the conference with their new insights about cellulosic derivatives and fibers. [...]info:eu-repo/semantics/publishedVersio
The migrant character in As maçãs azuis
Este artigo analisa a possibilidade da narrativa autobiográfica As Maçãs Azuis: Portugal e Goa 1948-1961 (1987) de Edila Gaitonde ser considerada uma obra de literatura de migração. Para tal, analisar-se-ão duas questões consideradas centrais na Literatura de Migração: a questão da identidade híbrida da personagem migrante e a questão da fronteira, aspetos intimamente relacionados entre si. O percurso da protagonista é o de um ser migrante, marcado pela mudança e pelo movimento, que atravessou constantemente fronteiras, não só físicas, mas também, e sobretudo, culturais, sociais, linguísticas e político-ideológicas. Em virtude de ter contraído matrimónio com um médico nacionalista hindu e opositor ao regime colonial português, os desafios enfrentados pela personagem estão marcados pelo seu encontro com o Oriente (ou com as diversas realidades sociopolíticas e culturais da Índia) aquando da mudança para essa parte do globo, assim como pelo combate político ao partilhar com o esposo os valores da democracia e o sonho de uma Goa independente. A transposição constante de fronteiras repercutiu-se na identidade açoriana-portuguesa-católica-ocidental da protagonista, em resultado das relações de vária ordem (pessoais, familiares ou sociais) estabelecidas com a heterogeneidade de comunidades existentes em Goa ¾ a comunidade portuguesa constituída pela população oriunda da metrópole e que estava no território ao serviço do Estado Português, representando-o, e as comunidades autóctones cristã e hindu de Goa. A integração da personagem nesse espaço sociocultural levou a uma reconfiguração da sua identidade, que se traduziu na formação de uma identidade híbrida, a qual favoreceu, por seu turno, o equilíbrio almejado pela personagem com vista a conciliar a sua identidade cultural ocidental com a das comunidades existentes no Oriente, particularmente a hindu, procurando evitar ou minimizar o choque cultural.In this paper we analise the possibility to consider the autobiographical narrative In Search of Tomorrow
(1987) by Edila Gaitonde to be considered migration literature. Therefore, we will study two issues considered
central in Migration Literature: the issue of migrant fictional character’s hybrid identity and the issue of
borders, items related the one to the other.
The life course of the protagonist is identified as a “migrant”, emphasized by the changes and movements,
who constantly crossed borders not only physical ones but mainly cultural, social, linguistic, political and
ideological borders. When leaving to another country due to her marriage to a Hindustan nationalist doctor
and an opponent to the Portuguese colonial regime, she deals with the challenges of the Eastern culture
(or the different social, cultural and political realities of India). At the same time, the protagonist fights a
political battle sharing with her husband the values of democracy and the dream of an independent Goa.
The constant cross-border movement had consequences in the Azorean-Portuguese-catholic-western identity
of the protagonist, because of the several types of relationships (personal, family or social) established
within the heterogeneity of the communities of Goa. The Portuguese community came from the mainland
and it was established in the territory to serve and to represent the Portuguese government as well as the
Christian and Hindu autochthone communities of Goa. On the one hand, the integration of the protagonist
in that social and cultural environment led to a reconfiguration of her identity which can be translated in
the building up of a hybrid identity. On the other hand, expecting to diminished or avoid the cultural shock,
that hybrid identity sought a balance in order to conciliate the protagonist’s cultural western identity with
those of the Eastern communities, particularly the Hindi community.info:eu-repo/semantics/publishedVersio
The use of Keratin in biomedical applications
Keratins are naturally derived proteins that can be fabricated into several biomaterials morphologies including films, sponges and hydrogels. As a physical matrix, keratin biomaterials have several advantages of both natural and synthetic materials that are useful in tissue engineering and controlled released applications. Like other naturally derived protein biomaterials, such as collagen, keratin possess amino acid sequences, similar to the ones found on extracellular matrix (ECM), that may interact with integrins showing their ability to support cellular attachment, proliferation and migration. The ability of developing biomaterials that mimic ECM has the potential to control several biological processes and this is the case for keratin which has been used in a variety of biomedical applications due to its biocompatibility and biodegradability. This review describes the progress to date towards the use of keratin in the field of wound healing, tissue engineering and drug delivery applications, with highlight to reports of particular relevance to the development of the underlying biomaterials science in this area
Role of PEG on the formation of polyphenols with laccase enzymes
Laccase catalyzes the polymerization of phenolic compounds in the presence of Laccase catalyzes the polymerization of phenolic compounds in the presence of oxygen. It is known that polyethylene glycol (PEG) enhances transformation of the phenols. oxygen. It is known that polyethylene glycol (PEG) enhances transformation of the phenols. High conversation rates and high yields are obtained in presence of PEG. PEG is believed to High conversation rates and high yields are obtained in presence of PEG. PEG is believed to protect the enzyme of being entrapped inside the formed polymer. However the mechanisms protect the enzyme of being entrapped inside the formed polymer. However the mechanisms by what the PEG enhances the reaction are not completely clear. The structure and by what the PEG enhances the reaction are not completely clear. The structure and aggregation of the polyphenols are different when obtained in the presence of PEG. PEG aggregation of the polyphenols are different when obtained in the presence of PEG. PEG seems to play an important role as interfacial agent on the region selectivity in the seems to play an important role as interfacial agent on the region selectivity in the polymerization reaction catalyzed by laccase enzymes.info:eu-repo/semantics/updatedVersio
Nanotechnology: definitions and concepts
NANOFOL NanoDiaRA Conference in the 7th Framework Programme: Nanoparticles for Early Diagnostics of Inflammatory Diseases | New approaches in the field of soft and hard nanoparticlesMassive amount of funds have been allocated for the research in
Nanotechnology. It is not always clear the boundaries between
Micro and Nano areas. Definitions are very broad depending on
the disciplinary area. Bold names from several disciplines exist like
bionanotechnology, nanomedicine, nanomaterials, nanoformulation,
nanoelectronics, nanofluidics, nanoparticles, nanosensors
and others. In spite of view of the huge impact of definitions on
research funding, regulations, toxicity, investigation and
accreditation of new products, it is important to know and to
understand the origin and reasons for these different approaches to
those definitions. Definitions and examples from the literature as
well as from the own research are given. This tutorial aims to clarify
those misconceptions.info:eu-repo/semantics/publishedVersio
Migratory short stories by Dora Nunes Gago
De acordo com a conceção de Søren Frank (2008), que defende que a migração só se pode inscrever na obra literária pela conjugação do conteúdo – as temáticas abordadas e / ou a condição migrante das personagens –, com a forma – as estratégias discursivas implementadas –, propomo-nos analisar os contos que constituem a obra Travessias – Contos Migratórios (2014) de Dora Nunes Gago. Partindo da reflexão em torno das designações “contos migratórios” e conto de/sobre migração, procurar-se-á identificar as estratégias discursivas postas ao serviço das temáticas tratadas e, desse modo, constatar em que medida o conceito de migração se converte numa característica intratextual da obra literária e não meramente um tema literariamente explorado.According to Søren Frank (2008), migration can only be inscribed in the literary work by the
conjugation of the content – the themes and / or the migrant condition of the characters – with
the form – the discursive strategies. We analyze the short stories included in the book Travessias
– Contos Migratótios (2014) by Dora Nunes Gago. Our reflection starts by the distinction
of the descriptions “migratory tales”, “tales of migration” or “tales on migration”. We identify
the discursive strategies put at the service of the topics treated and, thus, to verify to what
extent the concept of migration becomes a characteristic of the literary work and not merely
a literarily explored theme.info:eu-repo/semantics/publishedVersio
Effect of ultrasound on protein functionality
The review focus on the effect of ultrasound on protein functionality. The presence of transient ultrasonic mechanical waves induce various sonochemical and sonomechanical effects on a protein. Sonochemical effects include the breakage of chains and/or the modification of side groups of aminoacids. Sonomechanical modifications by enhanced molecular agitation, might lead to the transient or permanent modification of the 3D structure of the folded protein. Since the biological function of proteins depends on the maintenance of its 3D folded structure, both sonochemical and sonomechanical effects might affect its properties. A protein might maintain its 3D structure and functionality after minor sonochemical effects, however, the enhanced mass transfer by sonomechanical effects might expose internal hydrophobic residues of the protein, making protein unfolding to an irreversible denatured state. Ultrasound enhanced mass transport effects are unique pathways to change the 3D folded structure of proteins which lead to a new functionality of proteins as support shield materials during the formation microspheres. Enzymes are proteins and their reactions should be conducted in a reactor set-up where enzymes are protected from sonic waves to maximize their catalytic efficiency. In this review, focused examples on protein dispersions/emulsions and enzyme catalysis are given.National Natural Science Foundation of China (No.52003108) and the Fundamental Research Funds for the Central Universities (JUSRP121027). This research was also 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 European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norteinfo:eu-repo/semantics/publishedVersio
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