Microalgae Polysaccharides: An Overview of Production, Characterization, and Potential Applications

Microalgae and cyanobacteria are photosynthetic microorganisms capable of synthesizing several biocompounds, including polysaccharides with antioxidant, antibacterial, and antiviral properties. At the same time that the accumulation of biomolecules occurs, microalgae can use wastewater and gaseous effluents for their growth, mitigating these pollutants. The increase in the production of polysaccharides by microalgae can be achieved mainly through nutritional limitations, stressful conditions, and/or adverse conditions. These compounds are of commercial interest due to their biological and rheological properties, which allow their application in various sectors, such as pharmaceuticals and foods. Thus, to increase the productivity and competitiveness of microalgal polysaccharides with commercial hydrocolloids, the cultivation parameters and extraction/purification processes have been optimized. In this context, this review addresses an overview of the production, characterization, and potential applications of polysaccharides obtained by microalgae and cyanobacteria. Moreover, the main opportunities and challenges in relation to obtaining these compounds are highlighted.

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The Infuence of Salicin on Rheological and Film-Forming Properties of Collagen

Molecules ◽

10.3390/molecules26061661 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1661

Author(s):

Katarzyna Adamiak ◽

Katarzyna Lewandowska ◽

Alina Sionkowska

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Infrared Spectroscopy ◽

Rheological Properties ◽

Silver Carp ◽

Shear Tests ◽

Force Microscopy ◽

Atomic Force ◽

Film Forming ◽

Potential Applications

Collagen films are widely used as adhesives in medicine and cosmetology. However, its properties require modification. In this work, the influence of salicin on the properties of collagen solution and films was studied. Collagen was extracted from silver carp skin. The rheological properties of collagen solutions with and without salicin were characterized by steady shear tests. Thin collagen films were prepared by solvent evaporation. The structure of films was researched using infrared spectroscopy. The surface properties of films were investigated using Atomic Force Microscopy (AFM). Mechanical properties were measured as well. It was found that the addition of salicin modified the roughness of collagen films and their mechanical and rheological properties. The above-mentioned parameters are very important in potential applications of collagen films containing salicin.

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Evaluation of the Growth Performance of Microalgae Based on Fine pH Changes

Austin Journal of Biotechnology & Bioengineering ◽

10.26420/austinjbiotechnolbioeng.2021.1109 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Filali R ◽

◽

Tian H ◽

Micheils E ◽

Taidi B ◽

...

Keyword(s):

Growth Rate ◽

Carbon Content ◽

Specific Growth ◽

Optimal Growth ◽

Microalgae Cultivation ◽

Photoautotrophic Growth ◽

Microalgae Culture ◽

Potential Applications ◽

Photosynthetic Microorganisms ◽

Range Of Values

Microalgae are photosynthetic microorganisms with many potential applications in the food, cosmetics, pharmaceutical and environmental industries. Currently, commercial microalgae production remains limited. Therefore, improving the growth and the culture density of the microalgae cultivation is one of the key enablers to open the way to mass production and commercialisation of these microorganisms. The effect of culture pH on the photoautotrophic growth of C. vulgaris over a large range of values has been investigated in pH-regulated cultures. For each microalgae culture, the specific growth rate, the cell density, the chlorophyll content, the intracellular carbon content and the nitrogen source consumption were monitored. Optimal growth and carbon incorporation have been observed at pH of 7.0. The fastest growth rate and highest biomass production of C. vulgaris were 0.074 h-1 and 0.896 g/L respectively. Under these conditions, a maximum carbon content of cells was 49 % (w/w).

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Effect of Electron Beam Irradiation on the Rheological Properties and Phase Transition Temperature of Poly(N-Vinylcaprolactam)

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.865.19 ◽

2020 ◽

Vol 865 ◽

pp. 19-24

Author(s):

Shane C. Halligan ◽

Kieran A. Murray ◽

Olivier Vrain ◽

John G. Lyons ◽

Luke M. Geever

Keyword(s):

Phase Transition ◽

Electron Beam ◽

Rheological Properties ◽

Smart Materials ◽

Electron Beam Irradiation ◽

Beam Irradiation ◽

Beam Radiation ◽

Rheological Analysis ◽

Novel Approach ◽

Potential Applications

Exposing smart materials to electron beam radiation can induce free radical reactions, such as chain branching or crosslinking, hence enhancing the characteristics of the polymers. Poly (N-vinylcaprolactam) (PNVCL) is a smart material which was synthesised by photopolymerisation. Subsequently, samples were exposed to electron beam technology, where electron beam irradiation was utilised in a novel approach. This led to the modification of the rheological and phase transition properties. Modifying PNVCL through electron beam irradiation opens new avenues and potential applications in the biomedical field. Physically cross-linked PNVCL polymers were prepared by photopolymerisation and samples were subsequently irradiated at different dose ranges (5kGy, 25kGy and 50 kGy). The rheological properties of the PNVCL based samples were established by rheological analysis. Similarly, the PNVCL based sample polymers were further characterised in solution to determine the phase transition of PNVCL.

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Flow cytometry as a valuable tool to study cyanobacteria:A mini-review

Limnological Review ◽

10.1515/limre-2017-0009 ◽

2017 ◽

Vol 17 (2) ◽

pp. 89-95 ◽

Cited By ~ 4

Author(s):

Barbara Poniedziałek ◽

Halina I. Falfushynska ◽

Piotr Rzymski

Keyword(s):

Flow Cytometry ◽

Environmental Studies ◽

Small Sample ◽

Wide Spread ◽

Filamentous Cyanobacteria ◽

Potential Toxicity ◽

Wide Range ◽

Biochemical Studies ◽

Potential Applications ◽

Photosynthetic Microorganisms

AbstractFlow cytometry (FCM) is routinely used in medical and veterinary diagnostics although it is also widely applied in environmental studies, including phytoplankton investigations. Cyanobacteria are wide-spread photosynthetic microorganisms that attract attention due to their ecology and potential toxicity. Therefore, novel research tools are being applied in their investigation. This paper characterizes FCM as a technique that enables photopigments (chlorophylls and phycocyanin) expressed by cyanobacteria to be excited and their emission to be subsequently detected. This feature not only allows cells to be counted in a rapid manner but also enables a wide range of potential applications in ecological and biochemical studies. The main advantages of FCM, such as rapid, automatic and precise measurements requiring small sample volumes, are also discussed in this paper along with challenges including analyses of filamentous cyanobacteria and signal overlapping. It is expected that FCM will continue to be used in some fields of cyanobacterial studies.

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Rheological Properties of RLDPE/LLDPE Blends

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.268-270.115 ◽

2012 ◽

Vol 268-270 ◽

pp. 115-118

Author(s):

Xue Yan Zhao ◽

Xue Gang Luo ◽

Xiao Yan Lin ◽

Xiao Qi ◽

Hong Ping Zhang ◽

...

Keyword(s):

Rheological Properties ◽

Twin Screw Extruder ◽

Normal Flow ◽

Screw Extruder ◽

Rheological Analysis ◽

Twin Screw ◽

Potential Applications ◽

Small Content

Blends of recycled LDPE and LLDPE were prepared by the twin-screw extruder at different ratios. Recycled LDPE was used as matrix in this work, LLDPE was used to improve the properties of RLDPE. Virgin LDPE was used in this study as a contrast. Rheological properties of the blends were carefully evaluated by a Haake rheometer and compared with pure LDPE. Rheological analysis shows that virgin LLDPE will promote the normal flow of RLDPE in the a large content and hinder the mobility of chain segments when in a small content of LLDPE. Consequently, the blends show potential applications in high-value products.

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Alginate Lyases: Sources, Mechanism of Activity and Potencial Application

SQUALEN Bulletin of Marine and Fisheries Postharvest and Biotechnology ◽

10.15578/squalen.v8i3.39 ◽

2013 ◽

Vol 8 (3) ◽

pp. 105 ◽

Cited By ~ 1

Author(s):

Subaryono Subaryono ◽

Rosmawaty Peranginangin ◽

Maggy Thenawidjaja Suhartono ◽

Fransiska Rungkat Zakaria

Keyword(s):

Rheological Properties ◽

Structure Analysis ◽

Biological Activities ◽

Alginate Lyase ◽

Present Review ◽

Biological Engineering ◽

Alginate Oligosaccharides ◽

Potential Applications ◽

Growth Promoting ◽

Alginate Lyases

Alginate lyases are group of enzymes which catalyze depolymerization of alginate into oligosaccharides. Alginate lyase have been widely used in many applications such as in production of bioactive oligosaccharides, control of polysaccharide rheological properties, and polysaccharide structure analysis. The products of alginate lyase, polysaccharide structure analysis, alginate oligosaccharides (AOS) have many biological activities including act as prebiotics, immune modulator, anticoagulation, antioxidant, anticancer, growth promoting activities, promote production of antibiotics and ethanol. In relation to the importance of alginate lyases, their potential aplications and prospect in development of new bioactive products, we present review of the enzymes, sources, mechanism of activity and potential applications. This paper also discussed some new biological engineering in alginate lyase production.

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Preparation of Protein Oleogels: Effect on Structure and Functionality

Foods ◽

10.3390/foods9121745 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1745

Author(s):

Annika Feichtinger ◽

Elke Scholten

Keyword(s):

Rheological Properties ◽

Nutritional Value ◽

Food Products ◽

Consumer Acceptance ◽

Fat Replacer ◽

Preparation Methods ◽

Current State ◽

Short Summary ◽

Different Types ◽

Potential Applications

Among available structuring agents that have been used to provide solid properties to liquid oils, protein is a more recent candidate. Due to their nutritional value and high consumer acceptance, proteins are of special interest for the preparation of edible oleogels as an alternative for solid fats. Whereas the field of protein oleogelation is still rather new and just starts unfolding, several preparation methods have been demonstrated to be suitable for protein oleogel preparation. However, there is limited knowledge regarding the link between microstructural properties of the gels and macroscopic rheological properties, and the potential of such protein-based oleogels as a fat replacer in food products. In this review, we therefore provide an overview of various protein oleogel preparation methods and the resulting gel microstructures. Based on the different structures, we discuss how the rheological properties can be modified for the different types of protein oleogels. Finally, we consider the suitability of the different preparation methods regarding potential applications on industrial scale, and provide a short summary of the current state of knowledge regarding the behavior of protein oleogels as a fat replacer in food products.

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Rheological and Thermal Properties of Blends of Recycled LDPE and Virgin LDPE

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.734-737.2501 ◽

2013 ◽

Vol 734-737 ◽

pp. 2501-2504 ◽

Cited By ~ 1

Author(s):

Xue Yan Zhao ◽

Xue Gang Luo ◽

Xiao Yan Lin ◽

Xiao Qi

Keyword(s):

Thermal Properties ◽

Rheological Properties ◽

Crystalline Phase ◽

Normal Flow ◽

Screw Extruder ◽

Rheological Analysis ◽

Dsc Measurements ◽

Twin Screw ◽

Potential Applications ◽

Processing Properties

Blends of recycled LDPE and LDPE were prepared by the twin-screw extruder at different ratios. Recycled LDPE was used as matrix in this work, LDPE was used to improve the properties of RLDPE. Thermal and rheological properties of the blends were carefully evaluated and compared with pure LDPE. DSC measurements indicates that the RLDPE/LDPE blends are miscible in the crystalline phase and LDPE can increase the crystallization of the blends. Rheological analysis shows that virgin LDPE will promote the normal flow of RLDPE and improve the mobility of chain segments in flow. Consequently, the rheological and processing properties of the blends have improved compared to RLDPE. The blends show potential applications in high-value products.

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Influence of X-ray opaque BaSO4 nanoparticles on the mechanical, thermal and rheological properties of polyoxymethylene nanocomposites

Journal of Polymer Engineering ◽

10.1515/polyeng-2011-0135 ◽

2012 ◽

Vol 32 (4-5) ◽

pp. 319-326 ◽

Cited By ~ 9

Author(s):

Issis C. Romero-Ibarra ◽

Elizabeth Bonilla-Blancas ◽

Antonio Sánchez-Solís ◽

Octavio Manero

Keyword(s):

Rheological Properties ◽

Barium Sulfate ◽

Spherical Nanoparticles ◽

X Ray ◽

Transmission Electron ◽

The Matrix ◽

Dispersion State ◽

Twin Screw ◽

Potential Applications ◽

Nanoparticles Concentration

Abstract This work evaluates the influence of a radiopaque reinforcement, barium sulfate (BaSO4), on the mechanical, rheological and thermal properties of polyoxymethylene (POM). Nanocomposites of POM containing spherical nanoparticles of BaSO4 (0, 1, 2, 3 phr) were obtained by melt extrusion in a twin-screw equipment followed by injection molding. The mechanical, thermal and rheological properties of these nanocomposites and the dispersion state of the particles were investigated. Scanning and transmission electron microscopy revealed the morphology of the products. The main objective of this work is the production of nanocomposites with sulfate concentration enough to acquire radiopaque properties while maintaining the mechanical properties of the matrix. In this regard, mechanical and rheological properties were found similar to those of the polymer matrix, but radiopaque contrast tests revealed the influence of the nanoparticles concentration on the optical properties of the composites. The production of these nanocomposites suggests potential applications in the biomedical sector given their unique radio-opacity properties.

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Evolution of VANETS to IoV

Tehnički glasnik ◽

10.31803/tg-20210205104516 ◽

2021 ◽

Vol 15 (1) ◽

pp. 143-149

Author(s):

Faisal Rasheed Lone ◽

Harsh Kumar Verma ◽

Krishna Pal Sharma

Keyword(s):

Traffic Information ◽

The Internet ◽

Internet Of Vehicles ◽

Collision Warning ◽

Commercial Interest ◽

Passenger Safety ◽

Wide Range ◽

Potential Applications ◽

Smart Parking ◽

Collision Warning Systems

Advancement in wireless communication technology along with the evolution of low power computational devices, have given rise to the Internet of things paradigm. This paradigm is transforming conventional VANETs into Internet-of- vehicles. This transition has led to a substantial commercial interest; as a result, there has been a significant boost in the field of the Internet of vehicles during the past few years. IoV promises a wide range of applications of commercial interest as well as public entertainment and convenience (collision warning systems, on-demand in-car entertainment, smart parking, traffic information). Applications related to vehicular and passenger safety are particularly of great commercial as well as a research interest as such IoV is going to be a core component in implementing the smart city concept. This paper gives an overview of the transition of conventional VANETs to IoV and highlights the potential applications and challenges faced by the Internet of Vehicles (IoV) paradigm.

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