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Exploring the biomedical potential of a novel algae origin polysaccharide

Pinto, Anabela Alves
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Tese de Doutorado
Publicado em 09/03/2012 ENG
Relevância na Pesquisa
16.47%
Programa Doutoral em Engenharia Biomédica; During the past decades, marine organisms have been the focus of considerable attention as potential sources of valuable materials. The sustainable exploitation and valorisation of natural marine resources constitutes a highly attractive and strategic platform for the development of novel biomaterials, with both economic and environmental benefits. In this context, algae are well known to synthesise large quantities of polysaccharides. In fact, algae are well established sources of these particularly interesting molecules, many of which are known for their applicability in the design of biomaterials. Among the three main divisions of macroalgae, green algae remain largely unexploited in the biomedical arena. While the demand for novel materials and technologies increases, so does the amount of research focused on these unexploited marine green algae including its unique polysaccharide ulvan. As research on this polysaccharide evolves towards the study of its potential application in a biomedical context, the definition of effective processing routes becomes rather crucial. The main objective of the herein described work is the development of biomedical applications for this green algae polysaccharide...

Materials of marine origin : a review on polymers and ceramics of biomedical interest

Silva, Tiago H.; Alves, A.; Ferreira, B. M.; Oliveira, Joaquim M.; Reys, L. L.; Ferreira, R. J. F.; Sousa, R. A.; Silva, S. S.; Mano, J. F.; Reis, R. L.
Fonte: Maney Publishing Publicador: Maney Publishing
Tipo: Artigo de Revista Científica
Publicado em //2012 ENG
Relevância na Pesquisa
46.54%
Marine organisms are constituted by materials with a vast range of properties and characteristics that may justify their potential application within the biomedical field. Moreover, assuring the sustainable exploitation of natural marine resources, the valorisation of residues from marine origin, like those obtained from food processing, constitutes a highly interesting platform for development of novel biomaterials, with both economic and environmental benefits. In this perspective, an increasing number of different types of compounds are being isolated from aquatic organisms and transformed into profitable products for health applications, including controlled drug delivery and tissue engineering devices. This report reviews the work that is being developed on the isolation and characterisation of some polysaccharides, proteins, glycosaminoglycans and ceramics from marine raw materials. Emphasis is given to agar, alginates, carrageenans, chitin and chitosan, among other polysaccharides, collagen, glycosaminoglycans such as chondroitin sulphate, heparin and hyaluronic acid, calcium phosphorous compounds and biosilica. Finally, this report ends by reviewing the application of the previously mentioned materials on specific biomedical applications...

Marine algae sulfated polysaccharides for tissue engineering and drug delivery approaches

Silva, Tiago H.; Alves, A.; Popa, Elena G.; Reys, L. L.; Gomes, Manuela E.; Sousa, R. A.; Silva, S. S.; Mano, J. F.; Reis, R. L.
Fonte: Landes Bioscience Publicador: Landes Bioscience
Tipo: Artigo de Revista Científica
Publicado em //2012 ENG
Relevância na Pesquisa
46.5%
Biomedical field is constantly requesting for new biomaterials, with innovative properties. Natural polymers appear as materials of election for this goal due to their biocompatibility and biodegradability. In particular, materials found in marine environment are of great interest since the chemical and biological diversity found in this environment is almost uncountable and continuously growing with the research in deeper waters. Moreover, there is also a slower risk of these materials to pose illnesses to humans. In particular, sulfated polysaccharides can be found in marine environment, in different algae species. These polysaccharides don’t have equivalent in the terrestrial plants and resembles the chemical and biological properties of mammalian glycosaminoglycans. In this perspective, are receiving growing interest for application on health-related fields. On this review, we will focus on the biomedical applications of marine algae sulfated polymers, in particular on the development of innovative systems for tissue engineering and drug delivery approaches.; European Regional Development Fund (ERDF); Fundação para a Ciência e a Tecnologia (FCT)

A practical perspective on ulvan extracted from green algae

Alves, A.; Sousa, R. A.; Reis, R. L.
Fonte: Springer Publicador: Springer
Tipo: Conferência ou Objeto de Conferência
Publicado em //2013 ENG
Relevância na Pesquisa
16.42%
Researchers have many times turned their attention to nature and biological processes to develop novel technologies and materials. In a medical perspective, nature-based products are believed to be a strategic alternative approach to the use of fully synthetic materials, particularly in the design of medical devices. In the past decades, marine organisms have become the focus of considerable attention as potential sources of valuable materials. The sustainable exploitation and valorisation of natural marine resources constitutes a highly attractive and strategic platform for the development of novel biomaterials, with both economic and environmental benefits. In this context, algae are known to synthesise large quantities of polysaccharides and are well established sources of these particularly interesting molecules, many of which are known for their applicability in the design of biomaterials. Agar, carrageenan and alginates are some of the most known examples, and their uses can range from food to biomedical applications. However, few of the world’s available seaweed species are used commercially. Among the three main divisions of macroalgae (Chlorophyta, Phaeophyta and Rhodophyta), the green algae remain largely unexploited in this biomedical arena. While the demand for novel materials and technologies increases...

Revealing the potential of squid chitosan-based structures for biomedical applications

Reys, L. L.; Silva, S. S.; Oliveira, Joaquim M.; Caridade, S. G.; Mano, J. F.; Silva, Tiago H.; Reis, R. L.
Fonte: IOP Publishing Publicador: IOP Publishing
Tipo: Artigo de Revista Científica
Publicado em /05/2013 ENG
Relevância na Pesquisa
36.12%
In recent years, much attention has been given to different marine organisms, namely as potential sources of valuable materials with a vast range of properties and characteristics. In this work, β-chitin was isolated from the endoskeleton of the giant squid Dosidicus gigas and further deacetylated to produce chitosan. Then, the squid chitosan was processed into membranes and scaffolds using solvent casting and freeze-drying, respectively, to assess their potential biomedical application. The developed membranes have shown to be stiffer and less hydrophobic than those obtained with commercial chitosan. On the other hand, the morphological characterization of the developed scaffolds, by SEM and micro-computed tomography, revealed that the matrices were formed with a lamellar structure. The findings also indicated that the treatment with ethanol prior to neutralization with sodium hydroxide caused the formation of larger pores and loss of some lamellar features. The in vitro cell culture study has shown that all chitosan scaffolds exhibited a non-cytotoxic effect over the mouse fibroblast-like cell line, L929 cells. Thus, chitosan produced from the endoskeletons of the giant squid Dosidicus gigas has proven to be a valuable alternative to existing commercial materials when considering its use as biomaterial.

Combinatorial analysis of marine based biomaterials: high-throughput analysis of the effect of nanostructured multilayers on cell behaviour

Neto, Ana I.; Vasconcelos, Natália L.; Oliveira, Sara M.; Mano, J. F.
Fonte: Wiley & Sons, Inc. Publicador: Wiley & Sons, Inc.
Tipo: Conferência ou Objeto de Conferência
Publicado em /09/2013 ENG
Relevância na Pesquisa
26.42%
Publicado em "Journal of Tissue Engineering and Regenerative Medicine", vol. 7, supp. 1 (2013); In a marine environment, specific proteins are secreted by mussels and used as a bioglue to stick to a surface allowing generate irreversible bonding. Adhesive secreted proteins of mussels present an unusual amino acid 3,4-dihydroxyphenylalanine (DOPA). Inspired by the struc- ture and properties of mussel adhesive proteins, layer-by-layer (LbL) coatings based on polymers that contain catechol groups were devel- oped. We used dopamine-modified hyaluronic acid (HA-DN) prepared by carbodiimide chemistry to form thin and surface-adherent dopamine films. The multilayer films were developed by electrostatic interactions using chitosan (CHT) as polycation and HA-DN as polyanion. Multilay- ers films of CHT and HA were used as control. The formation of these films was investigated in-situ by quartz crystal microbalance with dissi- pation monitoring (QCM-D). Afterwards, many combinations of the marine inspired biomaterials were analysed in a high-throughput (HTS) way. Such multilayers were constructed and individually dis- posed on isolated transparent spots, patterned onto biomimetic super- hydrophobic substrates. The adhesion properties of the coatings in the chips were also analyzed. In vitro tests using two distinct cell sources were carried out to evaluate the biological performance of the different combinations of multilayers that could be useful in different biomedical applications...

Surface modification of silica-based marine sponge bioceramics induce hydroxyapatite formation

Barros, Alexandre A.; Aroso, Ivo; Silva, Tiago H.; Mano, J. F.; Duarte, Ana Rita C.; Reis, R. L.
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artigo de Revista Científica
Publicado em /08/2014 ENG
Relevância na Pesquisa
46.47%
Marine biomaterials are a new emerging area of research with significant applications. Recently, researchers are dedicating considerable attention to marine-sponge biomaterials for various applications. We have focused on the potential of biosilica from Petrosia ficidormis for novel biomedical/industrial applications. A bioceramic structure from this sponge was obtained after calcination at 750ºC for 6 hours in a furnace. The morphological characteristics of the 3D architecture were evaluated by scanning electron microscopy (SEM) and micro-computed tomography revealing a highly porous and interconnected structure. The skeleton of Petrosia ficidormis is a siliceous matrix composed of SiO2, which does not present inherent bioactivity. Induction of bioactivity was attained by subjecting the bioceramics structure to an alkaline treatment (KOH 2M) and acidic treatment (HCl 2M) for 1 and 3 hours. In vitro bioactivity of the bioceramics structure was evaluated in simulated body fluid (SBF), after 7 and 14 days. Observation of the structures by SEM, coupled with spectroscopic elemental analysis (EDS), has shown that the surface morphology presented a calcium-phosphate CaP coating, similar to hydroxyapatite (HA). The determination of the Ca/P ratio...

Marine inspired biomaterials : from sea up to tissue regeneration approaches

Silva, Tiago H.; Reis, R. L.
Fonte: John Wiley & Sons, Ltd. Publicador: John Wiley & Sons, Ltd.
Tipo: Conferência ou Objeto de Conferência
Publicado em /06/2014 ENG
Relevância na Pesquisa
46.77%
Introduction Nature has been since ever the inspiration driving mankind for the development of amazing systems, materials, constructions, devices, etc. Marine environment is not exception and the technological developments allowing the access to deeper locations and organisms are opening even more that gate to a new dimension of knowledge. One of the fields where marine organisms are acting stimulating the imagination of mankind is health, fostering the development of innovative pharmaceuticals and cosmetics, as well as new biomedical systems [1]. In this presentation, the authors will address the efforts that are being made by 3B’s Research Group on the development of marine inspired biomaterials towards tissue regeneration. Materials and Methods Polymer extraction Collagen has been extracted from several fish skins by acetic acid extraction, complemented by enzymatic treatment by using pepsin. Polysaccharides have been extracted from different marine sources, namely from algae (sulfated polysaccharides, typically using hot water and precipitation with organic solvents) and from squid pens (chitin, further converted into chitosan, by NaHO treatments). Development of biomaterials Porous structures have been developed following different processing techniques...

Marine origin collagens and its potential applications

Silva, Tiago H.; Silva, Joana M.; Marques, A. P.; Domingues, A.; Bayon, Yves; Reis, R. L.
Fonte: Molecular Diversity Preservation International Publicador: Molecular Diversity Preservation International
Tipo: Artigo de Revista Científica
Publicado em /12/2014 ENG
Relevância na Pesquisa
46.32%
Collagens are the most abundant high molecular weight proteins in both invertebrate and vertebrate organisms, including mammals, and possess mainly a structural role, existing different types according with their specific organization in distinct tissues. From this, they have been elected as one of the key biological materials in tissue regeneration approaches. Also, industry is constantly searching for new natural sources of collagen and upgraded methodologies for their production. The most common sources are from bovine and porcine origin, but other ways are making their route, such as recombinant production, but also extraction from marine organisms like fish. Different organisms have been proposed and explored for collagen extraction, allowing the sustainable production of different types of collagens, with properties depending on the kind of organism (and their natural environment) and extraction methodology. Such variety of collagen properties has been further investigated in different ways to render a wide range of applications. The present review aims to shed some light on the contribution of marine collagens for the scientific and technological development of this sector, stressing the opportunities and challenges that they are and most probably will be facing to assume a role as an alternative source for industrial exploitation.

Traditional and Modern Biomedical Prospecting: Part I—the History: Sustainable Exploitation of Biodiversity (Sponges and Invertebrates) in the Adriatic Sea in Rovinj (Croatia)

Müller, Werner E. G.; Batel, Renato; Schröder, Heinz C.; Müller, Isabel M.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
Publicado em /06/2004 EN
Relevância na Pesquisa
16.61%
Nature, especially the marine environment, provides the most effective drugs used in human therapy. Among the metazoans, the marine sponges (phylum Porifera), which are sessile filter feeders, produce the most potent and highly selective bioactive secondary metabolites. These animals (or their associated symbiotic microorganisms) synthesize secondary metabolites whose activity and selectivity has developed during their long evolutionary history (evochemistry). The exploitation of these resources has become possible due to the progress in molecular and cell biology. BIOTECmarin, the German Center of Excellence follows this rationale. In the past, these animals have been successfully and extensively utilized to isolate bioactive compounds and biomaterials for human benefit. Pharmaceuticals prepared from marine animals, primarily sponges, have been applied since ancient times (Hippocrates, Aristotle and later Plinius). It has been reported that extracts and/or components from sponges can be used for the treatment of specific diseases. For a systematic and applied-oriented exploitation, the successful development of effective compounds largely depends on quality of the institutional infrastructure of marine stations and more so on the biodiversity. The Center for Marine Research in Rovinj (Croatia) fulfils these prerequisites. Founded in 1891...

Chemical Structures and Bioactivities of Sulfated Polysaccharides from Marine Algae

Jiao, Guangling; Yu, Guangli; Zhang, Junzeng; Ewart, H. Stephen
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 08/02/2011 EN
Relevância na Pesquisa
26.21%
Sulfated polysaccharides and their lower molecular weight oligosaccharide derivatives from marine macroalgae have been shown to possess a variety of biological activities. The present paper will review the recent progress in research on the structural chemistry and the bioactivities of these marine algal biomaterials. In particular, it will provide an update on the structural chemistry of the major sulfated polysaccharides synthesized by seaweeds including the galactans (e.g., agarans and carrageenans), ulvans, and fucans. It will then review the recent findings on the anticoagulant/antithrombotic, antiviral, immuno-inflammatory, antilipidemic and antioxidant activities of sulfated polysaccharides and their potential for therapeutic application.

Bromophenols in Marine Algae and Their Bioactivities

Liu, Ming; Hansen, Poul Erik; Lin, Xiukun
Fonte: Molecular Diversity Preservation International Publicador: Molecular Diversity Preservation International
Tipo: Artigo de Revista Científica
Publicado em 22/07/2011 EN
Relevância na Pesquisa
26.21%
Marine algae contain various bromophenols that have been shown to possess a variety of biological activities, including antioxidant, antimicrobial, anticancer, anti-diabetic, and anti-thrombotic effects. Here, we briefly review the recent progress of these marine algal biomaterials, with respect to structure, bioactivities, and their potential application as pharmaceuticals.

Changing environments and structure–property relationships in marine biomaterials

Waite, J. Herbert; Broomell, Christopher C.
Fonte: Company of Biologists Publicador: Company of Biologists
Tipo: Artigo de Revista Científica
Publicado em 15/03/2012 EN
Relevância na Pesquisa
36.12%
Most marine organisms make functional biomolecular materials that extend to varying degrees ‘beyond their skins’. These materials are very diverse and include shells, spines, frustules, tubes, mucus trails, egg capsules and byssal threads, to mention a few. Because they are devoid of cells, these materials lack the dynamic maintenance afforded intra-organismic tissues and thus are usually assumed to be inherently more durable than their internalized counterparts. Recent advances in nanomechanics and submicron spectroscopic imaging have enabled the characterization of structure–property relationships in a variety of extra-organismic materials and provided important new insights about their adaptive functions and stability. Some structure–property relationships in byssal threads are described to show how available analytical methods can reveal hitherto unappreciated interdependences between these materials and their prevailing chemical, physical and ecological environments.

Marine algae sulfated polysaccharides for tissue engineering and drug delivery approaches

Silva, Tiago H.; Alves, Anabela; Popa, Elena G.; Reys, Lara L.; Gomes, Manuela E.; Sousa, Rui A.; Silva, Simone S.; Mano, João F.; Reis, Rui L.
Fonte: Landes Bioscience Publicador: Landes Bioscience
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.12%
Biomedical field is constantly requesting for new biomaterials, with innovative properties. Natural polymers appear as materials of election for this goal due to their biocompatibility and biodegradability. In particular, materials found in marine environment are of great interest since the chemical and biological diversity found in this environment is almost uncountable and continuously growing with the research in deeper waters. Moreover, there is also a slower risk of these materials to pose illnesses to humans.

Marine algal natural products with anti-oxidative, anti-inflammatory, and anti-cancer properties

Lee, Jin-Ching; Hou, Ming-Feng; Huang, Hurng-Wern; Chang, Fang-Rong; Yeh, Chi-Chen; Tang, Jen-Yang; Chang, Hsueh-Wei
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Publicado em 03/06/2013 EN
Relevância na Pesquisa
26.47%
For their various bioactivities, biomaterials derived from marine algae are important ingredients in many products, such as cosmetics and drugs for treating cancer and other diseases. This mini-review comprehensively compares the bioactivities and biological functions of biomaterials from red, green, brown, and blue-green algae. The anti-oxidative effects and bioactivities of several different crude extracts of algae have been evaluated both in vitro and in vivo. Natural products derived from marine algae protect cells by modulating the effects of oxidative stress. Because oxidative stress plays important roles in inflammatory reactions and in carcinogenesis, marine algal natural products have potential for use in anti-cancer and anti-inflammatory drugs.

Bioactive Marine Drugs and Marine Biomaterials for Brain Diseases

Grosso, Clara; Valentão, Patrícia; Ferreres, Federico; Andrade, Paula B.
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 02/05/2014 EN
Relevância na Pesquisa
36.52%
Marine invertebrates produce a plethora of bioactive compounds, which serve as inspiration for marine biotechnology, particularly in drug discovery programs and biomaterials development. This review aims to summarize the potential of drugs derived from marine invertebrates in the field of neuroscience. Therefore, some examples of neuroprotective drugs and neurotoxins will be discussed. Their role in neuroscience research and development of new therapies targeting the central nervous system will be addressed, with particular focus on neuroinflammation and neurodegeneration. In addition, the neuronal growth promoted by marine drugs, as well as the recent advances in neural tissue engineering, will be highlighted.

Evolving Marine Biomimetics for Regenerative Dentistry

Green, David W.; Lai, Wing-Fu; Jung, Han-Sung
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 13/05/2014 EN
Relevância na Pesquisa
26.12%
New products that help make human tissue and organ regeneration more effective are in high demand and include materials, structures and substrates that drive cell-to-tissue transformations, orchestrate anatomical assembly and tissue integration with biology. Marine organisms are exemplary bioresources that have extensive possibilities in supporting and facilitating development of human tissue substitutes. Such organisms represent a deep and diverse reserve of materials, substrates and structures that can facilitate tissue reconstruction within lab-based cultures. The reason is that they possess sophisticated structures, architectures and biomaterial designs that are still difficult to replicate using synthetic processes, so far. These products offer tantalizing pre-made options that are versatile, adaptable and have many functions for current tissue engineers seeking fresh solutions to the deficiencies in existing dental biomaterials, which lack the intrinsic elements of biofunctioning, structural and mechanical design to regenerate anatomically correct dental tissues both in the culture dish and in vivo.

Applications of Mass Spectrometry to Structural Analysis of Marine Oligosaccharides

Lang, Yinzhi; Zhao, Xia; Liu, Lili; Yu, Guangli
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 30/06/2014 EN
Relevância na Pesquisa
26.32%
Marine oligosaccharides have attracted increasing attention recently in developing potential drugs and biomaterials for their particular physical and chemical properties. However, the composition and sequence analysis of marine oligosaccharides are very challenging for their structural complexity and heterogeneity. Mass spectrometry (MS) has become an important technique for carbohydrate analysis by providing more detailed structural information, including molecular mass, sugar constituent, sequence, inter-residue linkage position and substitution pattern. This paper provides an overview of the structural analysis based on MS approaches in marine oligosaccharides, which are derived from some biologically important marine polysaccharides, including agaran, carrageenan, alginate, sulfated fucan, chitosan, glycosaminoglycan (GAG) and GAG-like polysaccharides. Applications of electrospray ionization mass spectrometry (ESI-MS) are mainly presented and the general applications of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) are also outlined. Some technical challenges in the structural analysis of marine oligosaccharides by MS have also been pointed out.

Chitin and Chitosan Preparation from Marine Sources. Structure, Properties and Applications

Younes, Islem; Rinaudo, Marguerite
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 02/03/2015 EN
Relevância na Pesquisa
26.12%
This review describes the most common methods for recovery of chitin from marine organisms. In depth, both enzymatic and chemical treatments for the step of deproteinization are compared, as well as different conditions for demineralization. The conditions of chitosan preparation are also discussed, since they significantly impact the synthesis of chitosan with varying degree of acetylation (DA) and molecular weight (MW). In addition, the main characterization techniques applied for chitin and chitosan are recalled, pointing out the role of their solubility in relation with the chemical structure (mainly the acetyl group distribution along the backbone). Biological activities are also presented, such as: antibacterial, antifungal, antitumor and antioxidant. Interestingly, the relationship between chemical structure and biological activity is demonstrated for chitosan molecules with different DA and MW and homogeneous distribution of acetyl groups for the first time. In the end, several selected pharmaceutical and biomedical applications are presented, in which chitin and chitosan are recognized as new biomaterials taking advantage of their biocompatibility and biodegradability.

Marine Polysaccharides from Algae with Potential Biomedical Applications

de Jesus Raposo, Maria Filomena; de Morais, Alcina Maria Bernardo; de Morais, Rui Manuel Santos Costa
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 15/05/2015 EN
Relevância na Pesquisa
26.26%
There is a current tendency towards bioactive natural products with applications in various industries, such as pharmaceutical, biomedical, cosmetics and food. This has put some emphasis in research on marine organisms, including macroalgae and microalgae, among others. Polysaccharides with marine origin constitute one type of these biochemical compounds that have already proved to have several important properties, such as anticoagulant and/or antithrombotic, immunomodulatory ability, antitumor and cancer preventive, antilipidaemic and hypoglycaemic, antibiotics and anti-inflammatory and antioxidant, making them promising bioactive products and biomaterials with a wide range of applications. Their properties are mainly due to their structure and physicochemical characteristics, which depend on the organism they are produced by. In the biomedical field, the polysaccharides from algae can be used in controlled drug delivery, wound management, and regenerative medicine. This review will focus on the biomedical applications of marine polysaccharides from algae.