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9923 KiB

Open AccessArticle

UV-Surface Treatment of Fungal Resistant Polyether Polyurethane Film-Induced Growth of Entomopathogenic Fungi

by Gabriela Albara Lando, Letícia Marconatto, Felipe Kessler, William Lopes, Augusto Schrank, Marilene Henning Vainstein and Daniel Eduardo Weibel

Int. J. Mol. Sci. 2017, 18(7), 1536; https://doi.org/10.3390/ijms18071536 - 18 Jul 2017

Cited by 12 | Viewed by 6977

Abstract

Synthetic polymers are the cause of some major environmental impacts due to their low degradation rates. Polyurethanes (PU) are widely used synthetic polymers, and their growing use in industry has produced an increase in plastic waste. A commercial polyether-based thermoplastic PU with hydrolytic [...] Read more.

Synthetic polymers are the cause of some major environmental impacts due to their low degradation rates. Polyurethanes (PU) are widely used synthetic polymers, and their growing use in industry has produced an increase in plastic waste. A commercial polyether-based thermoplastic PU with hydrolytic stability and fungus resistance was only attacked by an entomopathogenic fungus, Metarhiziumanisopliae, when the films were pre-treated with Ultraviolet (UV) irradiation in the presence of reactive atmospheres. Water contact angle, Fourier transform infrared spectroscopy in attenuated total reflection mode (FTIR-ATR), scanning electron microscopy (SEM), and profilometer measurements were mainly used for analysis. Permanent hydrophilic PU films were produced by the UV-assisted treatments. Pristine polyether PU films incubated for 10, 30, and 60 days did not show any indication of fungal growth. On the contrary, when using oxygen in the UV pre-treatment a layer of fungi spores covered the sample, indicating a great adherence of the microorganisms to the polymer. However, if acrylic acid vapors were used during the UV pre-treatment, a visible attack by the entomopathogenic fungi was observed. SEM and FTIR-ATR data showed clear evidence of fungal development: growth and ramifications of hyphae on the polymer surface with the increase in UV pre-treatment time and fungus incubation time. The results indicated that the simple UV surface activation process has proven to be a promising alternative for polyether PU waste management. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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3232 KiB

Open AccessArticle

Impact of Thermomechanical Fiber Pre-Treatment Using Twin-Screw Extrusion on the Production and Properties of Renewable Binderless Coriander Fiberboards

by Evelien Uitterhaegen, Laurent Labonne, Othmane Merah, Thierry Talou, Stéphane Ballas, Thierry Véronèse and Philippe Evon

Int. J. Mol. Sci. 2017, 18(7), 1539; https://doi.org/10.3390/ijms18071539 - 17 Jul 2017

Cited by 26 | Viewed by 5875

Abstract

The aim of this study consisted of manufacturing renewable binderless fiberboards from coriander straw and a deoiled coriander press cake, thus at the same time ensuring the valorization of crop residues and process by-products. The press cake acted as a natural binder inside [...] Read more.

The aim of this study consisted of manufacturing renewable binderless fiberboards from coriander straw and a deoiled coriander press cake, thus at the same time ensuring the valorization of crop residues and process by-products. The press cake acted as a natural binder inside the boards owing to the thermoplastic behavior of its protein fraction during thermopressing. The influence of different fiber-refining methods was evaluated and it was shown that a twin-screw extrusion treatment effectively improved fiber morphology and resulted in fiberboards with enhanced performance as compared to a conventional grinding process. The best fiberboard was produced with extrusion-refined straw using a 0.4 liquid/solid (L/S) ratio and with 40% press cake addition. The water sensitivity of the boards was effectively reduced by 63% through the addition of an extrusion raw material premixing operation and thermal treatment of the panels at 200 °C, resulting in materials with good performance showing a flexural strength of 29 MPa and a thickness swelling of 24%. Produced without the use of any chemical adhesives, these fiberboards could thus present viable, sustainable alternatives for current commercial wood-based materials such as oriented strand board, particleboard and medium-density fiberboard, with high cost-effectiveness. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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6108 KiB

Open AccessArticle

Anti-Biofilm Effect of Biodegradable Coatings Based on Hemibastadin Derivative in Marine Environment

by Tiffany Le Norcy, Hendrik Niemann, Peter Proksch, Isabelle Linossier, Karine Vallée-Réhel, Claire Hellio and Fabienne Faÿ

Int. J. Mol. Sci. 2017, 18(7), 1520; https://doi.org/10.3390/ijms18071520 - 13 Jul 2017

Cited by 18 | Viewed by 5836

Abstract

Dibromohemibastadin-1 (DBHB) is an already known potent inhibitor of blue mussel phenoloxidase (which is a key enzyme involved in bioadhesion). Within this study, the potentiality of DBHB against microfouling has been investigated. The activity of DBHB was evaluated on key strains of bacteria [...] Read more.

Dibromohemibastadin-1 (DBHB) is an already known potent inhibitor of blue mussel phenoloxidase (which is a key enzyme involved in bioadhesion). Within this study, the potentiality of DBHB against microfouling has been investigated. The activity of DBHB was evaluated on key strains of bacteria and microalgae involved in marine biofilm formation and bioassays assessing impact on growth, adhesion and biofilm formation were used. To assess the efficiency of DBHB when included in a matrix, DBHB varnish was prepared and the anti-microfouling activity of coatings was assessed. Both in vitro and in situ immersions were carried out. Confocal Laser Scanning Microscopy (CLSM) was principally used to determine the biovolume and average thickness of biofilms developed on the coatings. Results showed an evident efficiency of DBHB as compound and varnish to reduce the biofilm development. The mode of action seems to be based principally on a perturbation of biofilm formation rather than on a biocidal activity in the tested conditions. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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1168 KiB

Open AccessArticle

Synthesis and Biodegradation of Poly(l-lactide-co-β-propiolactone)

by Yuushou Nakayama, Kazuki Aihara, Zhengguo Cai, Takeshi Shiono and Chikara Tsutsumi

Int. J. Mol. Sci. 2017, 18(6), 1312; https://doi.org/10.3390/ijms18061312 - 20 Jun 2017

Cited by 13 | Viewed by 5269

Abstract

Although the copolymerizations of l-lactide (LA) with seven- or six-membered ring lactones have been extensively studied, the copolymerizations of LA with four-membered ring lactones have scarcely been reported. In this work, we studied the copolymerization of LA with β-propiolactone (PL) and the [...] Read more.

Although the copolymerizations of l-lactide (LA) with seven- or six-membered ring lactones have been extensively studied, the copolymerizations of LA with four-membered ring lactones have scarcely been reported. In this work, we studied the copolymerization of LA with β-propiolactone (PL) and the properties of the obtained copolymers. The copolymerization of LA with PL was carried out using trifluoromethanesulfonic acid as a catalyst and methanol as an initiator to produce poly(LA-co-PL) with M_n of ~50,000 and PL-content of 6–67 mol %. The T_g values of the copolymers were rapidly lowered with increasing PL-contents. The T_m and ΔH_m of the copolymers gradually decreased with increasing PL-contents, indicating their decreased crystallinity. Biodegradation test of the copolymers in compost demonstrated their improved biodegradability in comparison with the homopolymer of LA. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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1430 KiB

Open AccessArticle

Development of Biopolymer Composite Films Using a Microfluidization Technique for Carboxymethylcellulose and Apple Skin Particles

by Inyoung Choi, Yoonjee Chang, So-Hyang Shin, Eunmi Joo, Hyun Ju Song, Haeyoung Eom and Jaejoon Han

Int. J. Mol. Sci. 2017, 18(6), 1278; https://doi.org/10.3390/ijms18061278 - 15 Jun 2017

Cited by 29 | Viewed by 4953

Abstract

Biopolymer films based on apple skin powder (ASP) and carboxymethylcellulose (CMC) were developed with the addition of apple skin extract (ASE) and tartaric acid (TA). ASP/CMC composite films were prepared by mixing CMC with ASP solution using a microfluidization technique to reduce particle [...] Read more.

Biopolymer films based on apple skin powder (ASP) and carboxymethylcellulose (CMC) were developed with the addition of apple skin extract (ASE) and tartaric acid (TA). ASP/CMC composite films were prepared by mixing CMC with ASP solution using a microfluidization technique to reduce particle size. Then, various concentrations of ASE and TA were incorporated into the film solution as an antioxidant and an antimicrobial agent, respectively. Fourier transform infrared (FTIR), optical, mechanical, water barrier, and solubility properties of the developed films were then evaluated to determine the effects of ASE and TA on physicochemical properties. The films were also analyzed for antioxidant effect on 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and antimicrobial activities against Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica, and Shigella flexneri. From the results, the ASP/CMC film containing ASE and TA was revealed to enhance the mechanical, water barrier, and solubility properties. Moreover, it showed the additional antioxidant and antimicrobial properties for application as an active packaging film. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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3079 KiB

Open AccessArticle

Plasticizing Effects of Polyamines in Protein-Based Films

by Mohammed Sabbah, Prospero Di Pierro, C. Valeria L. Giosafatto, Marilena Esposito, Loredana Mariniello, Carlos Regalado-Gonzales and Raffaele Porta

Int. J. Mol. Sci. 2017, 18(5), 1026; https://doi.org/10.3390/ijms18051026 - 10 May 2017

Cited by 17 | Viewed by 4433

Abstract

Zeta potential and nanoparticle size were determined on film forming solutions of native and heat-denatured proteins of bitter vetch as a function of pH and of different concentrations of the polyamines spermidine and spermine, both in the absence and presence of the plasticizer [...] Read more.

Zeta potential and nanoparticle size were determined on film forming solutions of native and heat-denatured proteins of bitter vetch as a function of pH and of different concentrations of the polyamines spermidine and spermine, both in the absence and presence of the plasticizer glycerol. Our results showed that both polyamines decreased the negative zeta potential of all samples under pH 8.0 as a consequence of their ionic interaction with proteins. At the same time, they enhanced the dimension of nanoparticles under pH 8.0 as a result of macromolecular aggregations. By using native protein solutions, handleable films were obtained only from samples containing either a minimum of 33 mM glycerol or 4 mM spermidine, or both compounds together at lower glycerol concentrations. However, 2 mM spermidine was sufficient to obtain handleable film by using heat-treated samples without glycerol. Conversely, brittle materials were obtained by spermine alone, thus indicating that only spermidine was able to act as an ionic plasticizer. Lastly, both polyamines, mainly spermine, were found able to act as “glycerol-like” plasticizers at concentrations higher than 5 mM under experimental conditions at which their amino groups are undissociated. Our findings open new perspectives in obtaining protein-based films by using aliphatic polycations as components. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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1630 KiB

Open AccessArticle

Waste Soybean Oil and Corn Steep Liquor as Economic Substrates for Bioemulsifier and Biodiesel Production by Candida lipolytica UCP 0998

by Adriana Ferreira Souza, Dayana M. Rodriguez, Daylin R. Ribeaux, Marcos A. C. Luna, Thayse A. Lima e Silva, Rosileide F. Silva Andrade, Norma B. Gusmão and Galba M. Campos-Takaki

Int. J. Mol. Sci. 2016, 17(10), 1608; https://doi.org/10.3390/ijms17101608 - 23 Sep 2016

Cited by 28 | Viewed by 6259

Abstract

Almost all oleaginous microorganisms are available for biodiesel production, and for the mechanism of oil accumulation, which is what makes a microbial approach economically competitive. This study investigated the potential that the yeast Candida lipolytica UCP0988, in an anamorphous state, has to produce [...] Read more.

Almost all oleaginous microorganisms are available for biodiesel production, and for the mechanism of oil accumulation, which is what makes a microbial approach economically competitive. This study investigated the potential that the yeast Candida lipolytica UCP0988, in an anamorphous state, has to produce simultaneously a bioemulsifier and to accumulate lipids using inexpensive and alternative substrates. Cultivation was carried out using waste soybean oil and corn steep liquor in accordance with 2² experimental designs with 1% inoculums (10⁷ cells/mL). The bioemulsifier was produced in the cell-free metabolic liquid in the late exponential phase (96 h), at Assay 4 (corn steep liquor 5% and waste soybean oil 8%), with 6.704 UEA, IE₂₄ of 96.66%, and showed an anionic profile. The emulsion formed consisted of compact small and stable droplets (size 0.2–5 µm), stable at all temperatures, at pH 2 and 4, and 2% salinity, and showed an ability to remove 93.74% of diesel oil from sand. The displacement oil (ODA) showed 45.34 cm² of dispersion (central point of the factorial design). The biomass obtained from Assay 4 was able to accumulate lipids of 0.425 g/g biomass (corresponding to 42.5%), which consisted of Palmitic acid (28.4%), Stearic acid (7.7%), Oleic acid (42.8%), Linoleic acid (19.0%), and γ-Linolenic acid (2.1%). The results showed the ability of C. lipopytica to produce both bioemulsifier and biodiesel using the metabolic conversion of waste soybean oil and corn steep liquor, which are economic renewable sources. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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4735 KiB

Open AccessArticle

Protection of Historical Wood against Microbial Degradation—Selection and Application of Microbiocides

by Anna Koziróg, Katarzyna Rajkowska, Anna Otlewska, Małgorzata Piotrowska, Alina Kunicka-Styczyńska, Bogumił Brycki, Paulina Nowicka-Krawczyk, Marta Kościelniak and Beata Gutarowska

Int. J. Mol. Sci. 2016, 17(8), 1364; https://doi.org/10.3390/ijms17081364 - 22 Aug 2016

Cited by 20 | Viewed by 6125

Abstract

The aim of this study was to select effective and safe microbiocides for the disinfection and protection of historical wooden surfaces at the former Auschwitz II-Birkenau concentration and extermination camp. We tested seven active compounds against bacteria and moulds, of which didecyldimethylammonium chloride [...] Read more.

The aim of this study was to select effective and safe microbiocides for the disinfection and protection of historical wooden surfaces at the former Auschwitz II-Birkenau concentration and extermination camp. We tested seven active compounds against bacteria and moulds, of which didecyldimethylammonium chloride and N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine were effective even at 0.02%–2%. Subsequently, eight microbiocides containing the selected active ingredients were chosen and applied three times on the surface of wood samples colonized by bacteria and moulds. ABM-1 and ABM-2—6% solution; Rocima 101—8%; Preventol R 80—12%; Acticide 706 LV—15% and Boramon—30% were the most effective disinfectants. Under laboratory conditions, ABM-1, Boramon and Rocima 101 ensured antimicrobial protection of new wood samples for six months. In situ, 30% Boramon and 8% Rocima 101 applied by spraying effectively protected the historical wood from bacterial and mould growth for 12 and 3 months, respectively. Colour and luminance of the new wood were not altered after exposure to the biocides. Boramon and Rocima 101, applied by the spraying method, caused no significant change in the colour of the historical wood. Results from this study were used to develop a procedure for the protection of wood in historical buildings against biodeterioration. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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1770 KiB

Open AccessCommunication

Navicula sp. Sulfated Polysaccharide Gels Induced by Fe(III): Rheology and Microstructure

by Diana Fimbres-Olivarría, José Antonio López-Elías, Elizabeth Carvajal-Millán, Jorge Alberto Márquez-Escalante, Luis Rafael Martínez-Córdova, Anselmo Miranda-Baeza, Fernando Enríquez-Ocaña, José Eduardo Valdéz-Holguín and Francisco Brown-Bojórquez

Int. J. Mol. Sci. 2016, 17(8), 1238; https://doi.org/10.3390/ijms17081238 - 30 Jul 2016

Cited by 19 | Viewed by 6362

Abstract

A sulfated polysaccharide extracted from Navicula sp. presented a yield of 4.4 (% w/w dry biomass basis). Analysis of the polysaccharide using gas chromatography showed that this polysaccharide contained glucose (29%), galactose (21%), rhamnose (10%), xylose (5%) and mannose (4%). This [...] Read more.

A sulfated polysaccharide extracted from Navicula sp. presented a yield of 4.4 (% w/w dry biomass basis). Analysis of the polysaccharide using gas chromatography showed that this polysaccharide contained glucose (29%), galactose (21%), rhamnose (10%), xylose (5%) and mannose (4%). This polysaccharide presented an average molecular weight of 107 kDa. Scanning electron microscopy (SEM) micrographs showed that the lyophilized Navicula sp. polysaccharide is an amorphous solid with particles of irregular shapes and sharp angles. The polysaccharide at 1% (w/v) solution in water formed gels in the presence of 0.4% (w/v) FeCl₃, showing elastic and viscous moduli of 1 and 0.7 Pa, respectively. SEM analysis performed on the lyophilized gel showed a compact pore structure, with a pore size of approximately 150 nm. Very few studies on the gelation of sulfated polysaccharides using trivalent ions exist in the literature, and, to the best of our knowledge, this study is the first to describe the gelation of sulfated polysaccharides extracted from Navicula sp. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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Review

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5009 KiB

Open AccessReview

Impact of the Hydration States of Polymers on Their Hemocompatibility for Medical Applications: A Review

by Min A. Bag and Loreto M. Valenzuela

Int. J. Mol. Sci. 2017, 18(8), 1422; https://doi.org/10.3390/ijms18081422 - 03 Aug 2017

Cited by 89 | Viewed by 9165

Abstract

Water has a key role in the functioning of all biological systems, it mediates many biochemical reactions, as well as other biological activities such as material biocompatibility. Water is often considered as an inert solvent, however at the molecular level, it shows different [...] Read more.

Water has a key role in the functioning of all biological systems, it mediates many biochemical reactions, as well as other biological activities such as material biocompatibility. Water is often considered as an inert solvent, however at the molecular level, it shows different behavior when sorbed onto surfaces like polymeric implants. Three states of water have been recognized: non-freezable water, which does not freeze even at −100 °C; intermediate water, which freezes below 0 °C; and, free water, which freezes at 0 °C like bulk water. This review describes the different states of water and the techniques for their identification and quantification, and analyzes their relationship with hemocompatibility in polymer surfaces. Intermediate water content higher than 3 wt % is related to better hemocompatibility for poly(ethylene glycol), poly(meth)acrylates, aliphatic carbonyls, and poly(lactic-co-glycolic acid) surfaces. Therefore, characterizing water states in addition to water content is key for polymer selection and material design for medical applications. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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1341 KiB

Open AccessReview

The Ultimaster Biodegradable-Polymer Sirolimus-Eluting Stent: An Updated Review of Clinical Evidence

by Alberto Chisari, Anna Maria Pistritto, Raffaele Piccolo, Alessio La Manna and Gian Battista Danzi

Int. J. Mol. Sci. 2016, 17(9), 1490; https://doi.org/10.3390/ijms17091490 - 06 Sep 2016

Cited by 42 | Viewed by 8455

Abstract

The Ultimaster coronary stent system (Terumo Corporation, Tokyo, Japan) represents a new iteration in drug-eluting stent (DES) technology that has recently received the Conformité Européenne (CE) mark approval for clinical use. The Ultimaster is a thin-strut, cobalt chromium, biodegradable-polymer, sirolimus-eluting coronary stent. The [...] Read more.

The Ultimaster coronary stent system (Terumo Corporation, Tokyo, Japan) represents a new iteration in drug-eluting stent (DES) technology that has recently received the Conformité Européenne (CE) mark approval for clinical use. The Ultimaster is a thin-strut, cobalt chromium, biodegradable-polymer, sirolimus-eluting coronary stent. The high elasticity of the biodegradable-polymer (PDLLA-PCL) and the abluminal gradient coating technology are additional novel features of this coronary device. The Ultimaster DES has undergone extensive clinical evaluation in two studies: The CENTURY I and II trials. Results from these two landmark studies suggested an excellent efficacy and safety profile of the Ultimaster DES across several lesion and patient subsets, with similar clinical outcomes to contemporary, new-generation DES. The aim of this review is to summarize the rationale behind this novel DES technology and to provide an update of available evidence about the clinical performance of the Ultimaster DES. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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1571 KiB

Open AccessReview

Carbon Sources for Polyhydroxyalkanoates and an Integrated Biorefinery

by Guozhan Jiang, David J. Hill, Marek Kowalczuk, Brian Johnston, Grazyna Adamus, Victor Irorere and Iza Radecka

Int. J. Mol. Sci. 2016, 17(7), 1157; https://doi.org/10.3390/ijms17071157 - 19 Jul 2016

Cited by 166 | Viewed by 11661

Abstract

Polyhydroxyalkanoates (PHAs) are a group of bioplastics that have a wide range of applications. Extensive progress has been made in our understanding of PHAs’ biosynthesis, and currently, it is possible to engineer bacterial strains to produce PHAs with desired properties. The substrates for [...] Read more.

Polyhydroxyalkanoates (PHAs) are a group of bioplastics that have a wide range of applications. Extensive progress has been made in our understanding of PHAs’ biosynthesis, and currently, it is possible to engineer bacterial strains to produce PHAs with desired properties. The substrates for the fermentative production of PHAs are primarily derived from food-based carbon sources, raising concerns over the sustainability of their production in terms of their impact on food prices. This paper gives an overview of the current carbon sources used for PHA production and the methods used to transform these sources into fermentable forms. This allows us to identify the opportunities and restraints linked to future sustainable PHA production. Hemicellulose hydrolysates and crude glycerol are identified as two promising carbon sources for a sustainable production of PHAs. Hemicellulose hydrolysates and crude glycerol can be produced on a large scale during various second generation biofuels’ production. An integration of PHA production within a modern biorefinery is therefore proposed to produce biofuels and bioplastics simultaneously. This will create the potential to offset the production cost of biofuels and reduce the overall production cost of PHAs. Full article

(This article belongs to the Special Issue Biodegradable Materials 2017)

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