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Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-08-25T16:15:33Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_karine_laste_macagnan.pdf: 989328 bytes, checksum: a2029037b34e4625051db4296d4fad83 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-08-28T20:59:34Z (GMT) No. of bitstreams: 2 dissertacao_karine_laste_macagnan.pdf: 989328 bytes, checksum: a2029037b34e4625051db4296d4fad83 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-08-28T20:59:41Z (GMT) No. of bitstreams: 2 dissertacao_karine_laste_macagnan.pdf: 989328 bytes, checksum: a2029037b34e4625051db4296d4fad83 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-08-28T20:59:48Z (GMT). No. of bitstreams: 2 dissertacao_karine_laste_macagnan.pdf: 989328 bytes, checksum: a2029037b34e4625051db4296d4fad83 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-12-04 / Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul - FAPERGS / O poli(3-hidroxibutirato) [P(3HB)] é o biopolímero mais estudado e caracterizado dentre a família dos polihidroxialcanoatos (PHAs), termoplásticos que têm como principais características a rápida biodegradabilidade e a biocompatibilidade. O processo de recuperação do bioplástico consiste em uma etapa importante no processo de produção. O desenvolvimento de metodologias mais seguras, econômicas e ambientalmente corretas, e que permitam um alto rendimento desse biopolímero, torna-se necessário para uma produção de P(3HB) economicamente e ecologicamente atrativa. Portanto, o objetivo do trabalho foi otimizar a metodologia clássica de recuperação de poli(3-hidroxibutirato) utilizando clorofórmio como solvente. O bioprocesso foi realizado em duas etapas, utilizando linhagem de Ralstonia solanacearum. O inoculo foi produzido em Erlenmeyers aletados de 500 mL, contendo 160 mL de meio YM e 40 mL de suspensão bacteriana, mantidos em incubador agitador orbital por 24 h, 150 rpm e 28 °C. A segunda etapa, produção de P(3HB), foi realizada utilizando Erlenmeyers aletados de 500 mL, contendo 160 mL de meio F4 e 20 % de inóculo, mantidos em 28 °C, 200 rpm e 72 h em incubador agitador orbital. Após a fermentação, as células foram separadas por centrifugação a 10.000 x g, lavadas com solução salina 0,89 % e secas a 56 °C. O acúmulo de P(3HB) na célula foi quantificado por cromatografia gasosa. A metodologia de extração foi otimizada em relação aos parâmetros: tempo de extração (2 h a 15 min), separação da biomassa/solução extrativa (papel filtro ou funil de separação), estado de célula (seca ou fresca) e proporção de solvente (10:1, 20:1 e 40:1 v/m). Por evaporação da solução extrativa foram obtidos filmes poliméricos. Os filmes recuperados foram analisados física e quimicamente por Espectroscopia de Infravermelho por Transformada de Fourier (FTIR), Calorimetria Diferencial de Varredura (DSC), Análise Termogravimétrica (TGA) e Cromatografia de Permeação em Gel (GPC). O acúmulo de P(3HB) foi de 51,15 %. Os maiores rendimentos de filme foram obtidos após 30 min de aquecimento, utilizando funil de decantação para separar a solução extrativa da biomassa, célula seca, e proporção de solvente 40:1 v/m, alcançando-se recuperação de 98 % do polímero acumulado. A análise dos filmes através de FTIR resultou em bandas características de P(3HB). Os filmes oriundos de células secas tiveram temperaturas inicial e final de degradação e grau de cristalinidade superiores aos filmes de célula fresca. Todavia, os últimos apresentaram massa molar maior do que os primeiros. A metodologia clássica de extração química de poli(3-hidroxibutirato) por clorofórmio com aquecimento pode ser otimizada, resultando em redução de 75 % do tempo de aquecimento e separação da biomassa/solução extrativa mais rápida e econômica. Porém, não foi possível substituir a utilização de massa celular seca por fresca nem reduzir a proporção inicial de solvente de 40:1 (v/m). / Poly (3-hydroxybutyrate) [P(3HB)] is the most important biopolymer from the polyhydroalcanoates (PHAs) families, and they are thermoplastics with rapid biodegradability and biocompatibility. The recovery process of bioplastics is an important stage in the production process. Development of safe, economic and environmentally friendly methodologies, that result in high yield biopolymer, is necessary for the attractive P(3HB) production. Therefore, the objective was to optimize the classical methodology for poly (3-hydroxybutyrate) recovery using chloroform as solvent. The bioprocess was performed in two phases, with Ralstonia solanacearum strain. In the first phase, inoculum production, was performed in Erlenmeyer 500 mL flasks, containing 160 mL medium YM and 40 mL bacterial suspension. The flasks were incubated in shaker for 24 h, 150 rpm and 28 °C. The second phase, P(3HB) production, was performed using Erlenmeyer 500 mL flask, containing 160 mL medium F4 and 20 % (v/v) inoculum, maintained in 28 °C, 200 rpm and 72 h. After fermentation cells were separated by centrifugation at 10,000 x g, washed with saline (0,89 % w/v) and dried at 56 °C. P(3HB), accumulation was quantified by gas chromatography. The extraction methodology was optimized according to: extraction time (2 h - 15 min), extractive solution/biomass separation (paper filter or separation funnel), state of cell (dry or fresh), and solvent ratio (10:1, 20:1 and 40:1 v/m). Polymeric films were obtained by evaporation from extractive solutions and they were analysed by Fourier Transform Infrared (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) and Gel Permeation Chromatography (GPC). The P(3HB) accumulation was 51,15 %. Highest yields of film were obtained after 30 min heating, by funnel for extractive solution recovery, dry cell and solvent ratio 40:1 v/m; and highest recovery was 98 % of cumulated polymer in the cell. Characteristic bands of P(3HB) were obtained to produced films by FTIR analysis. Films from dried cells showed initial and final degradation temperature and crystallinity degree higher than and films these from fresh cell, however, they showed higher molar weight than the first ones. The classical chemical extraction of P(3HB) by chloroform with heating can be optimized, resulting in a 75 % reduction as well heating time extraction solution most fastest and economical. However, wasn’t possible replace the dry cell mass use by fresh cell mass or reduce the initial solvent proportion [40:1 (v/m)].

Starch-derived bioplastics are an inexpensive, renewable and environmentally-friendly alternative to traditional petroleum-based plastics. Proteins secreted by Ophiostoma ulmi, were investigated for their application in bioplastic product. Proteins were isolated from fungal cultures by anion exchange chromatography and used to treat starch. Subsequently, plastic films were generated by solution casting, with glycerol as plasticizer. Tensile strength of the films was found to increase significantly compared to the control. The relative water holding capacity of the treated starch also decreased dramatically. Attempts to identify fungal proteins by MALDI-TOF MS/MS did not result in positive matches, mainly due to lack of fungal sequence information. Additionally, the effect of non-specific proteins resulted in a modest increase in tensile strength and a slightly greater effect on water absorption. Proteins secreted by O. ulmi were therefore implicated in improving properties of starch-based plastics. Investigation into the role of an extracellular polysaccharide is also suggested.

Starch-derived bioplastics are an inexpensive, renewable and environmentally-friendly alternative to traditional petroleum-based plastics. Proteins secreted by Ophiostoma ulmi, were investigated for their application in bioplastic product. Proteins were isolated from fungal cultures by anion exchange chromatography and used to treat starch. Subsequently, plastic films were generated by solution casting, with glycerol as plasticizer. Tensile strength of the films was found to increase significantly compared to the control. The relative water holding capacity of the treated starch also decreased dramatically. Attempts to identify fungal proteins by MALDI-TOF MS/MS did not result in positive matches, mainly due to lack of fungal sequence information. Additionally, the effect of non-specific proteins resulted in a modest increase in tensile strength and a slightly greater effect on water absorption. Proteins secreted by O. ulmi were therefore implicated in improving properties of starch-based plastics. Investigation into the role of an extracellular polysaccharide is also suggested.

abstract: Fossil resources have enabled the development of the plastic industry in the last century. More recently biopolymers have been making gains in the global plastics market. Biopolymers are plastics derived from plants, primarily corn, which can function very similarly to fossil based plastics. One difference between some of the dominant biopolymers, namely polylactic acid and thermoplastic starch, and the most common fossil-based plastics is the feature of compostability. This means that biopolymers represent not only a shift from petroleum and natural gas to agricultural resources but also that these plastics have potentially different impacts resulting from alternative disposal routes. The current end of life material flows are not well understood since waste streams vary widely based on regional availability of end of life treatments and the role that decision making has on waste identification and disposal. This dissertation is focused on highlighting the importance of end of life on the life-cycle of biopolymers, identifying how compostable biopolymer products are entering waste streams, improving collection and waste processing, and quantifying the impacts that result from the disposal of biopolymers. Biopolymers, while somewhat available to residential consumers, are primarily being used by various food service organizations trying to achieve a variety of goals such as zero waste, green advertising, and providing more consumer options. While compostable biopolymers may be able to help reduce wastes to landfill they do result in environmental tradeoffs associated with agriculture during the production phase. Biopolymers may improve the management for compostable waste streams by enabling streamlined services and reducing non-compostable fossil-based plastic contamination. The concerns about incomplete degradation of biopolymers in composting facilities may be ameliorated using alkaline amendments sourced from waste streams of other industries. While recycling still yields major benefits for traditional resins, bio-based equivalents may provide addition benefits and compostable biopolymers offer benefits with regards to global warming and fossil fuel depletion. The research presented here represents two published studies, two studies which have been accepted for publication, and a life-cycle assessment that will be submitted for publication. / Dissertation/Thesis / Doctoral Dissertation Civil and Environmental Engineering 2015

Tesis por compendio / This PhD dissertation focuses on the development of renewable and biodegradable active films based on chemically-modified wheat gliadin proteins endowed with antimicrobial capacity owing to the incorporation of naturally-occurring bioactive compounds, namely cinnamaldehyde, natamycin, and lysozyme. Gliadin proteins were treated with cinnamaldehyde at acidic pH and films were produced by casting. The resulting protein-based films presented improved functional properties (mechanical, barrier, and water resistance), and biochemical evidence of the formation of a more compact network whose degree of cross-linking increased with the amount of cinnamaldehyde incorporated into the gliadin-ethanolic solution. Free cinnamaldehyde not participating in the cross-linked reaction remained entrapped in the protein matrix at low relative humidity conditions. The sensitivity of the films to moisture owing to the hydrophilic character of gliadins provided a trigger and control mechanism for the release of cinnamaldehyde in moderate and high relative humidity environments, similar to conditions occurring in packaged food products. The antimicrobial properties of the films developed were tested in vitro by vapor diffusion assays against common food spoilage fungi (Penicillium expansum and Aspergillus niger), showing great effectiveness. Application of these active films to the preservation of two foodstuffs, sliced bread and cheese spread, gave promising results, lengthening fungal growth lag phase and minimizing fungal growth extension. / Balaguer Grimaldo, MDLP. (2015). Development of active bioplastics based on wheat proteins and natural antimicrobials for food packaging applications [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48520 / TESIS / Premios Extraordinarios de tesis doctorales / Compendio

Within Alinea, the purpose is to explore the use of bioplastic as unconventional yarn in the traditional technique of handweaving. The focus toward bioplastic as a design material and the technique of handweaving as the fabrication technique to generate broader alternatives for using bioplastic materials in woven textile design. Described through experimental and practise-based research, handwoven bioplastic samples have been explored to investigate the methods of structures and bindings, gradient colouring and print design within bioplastic and weaving. With the attempt to make bioplastic more accessible for the textile industry. The experimental design research resulted in scaled prototypes that showcase a collection of seven pieces that present various design possibilities and potentials regarding bioplastic within the textile weaving technique, including distinct structural tactile qualities bioplastics can offer to the field of textile. It can be concluded that bioplastic can play a role in becomes a desirable material steering textile design towards a more sustainable future in the textile design field. Furthermore, give handwoven materials new aesthetics by producing unique structures and tactile features.

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The overall goal of this research was to explore new living radical polymerization methods and the blending of renewable polymers. Towards this latter goal, polylactic acid (PLA) was blended with a new renewable polymer, poly(trimethylene-malonate) (PTM), with the aim of improving mechanical properties, imparting faster degradation, and examining the relationship between degradation and mechanical properties. Blend films of PLA and PTM with various ratios (5, 10, and 20 wt %) were cast from chloroform. Partially miscible blends exhibited Young’s modulus and elongation-to-break values that significantly extend PLA’s usefulness. Atomic force microscopy (AFM) data showed that incorporation of 10 wt% PTM into PLA matrix exhibited a Young’s modulus of 4.61 GPa, which is significantly higher than that of neat PLA (1.69 GPa). The second part of the bioplastics study involved a one-week hydrolytic degradation study of PTM and another new bioplastic, poly(trimethylene itaconate) (PTI) using DI water (pH 5.4) at room temperature, and the effects of degradation on crystallinity and mechanical properties of these films were examined by differential scanning calorimetry (DSC) and AFM. PTI showed an increase in crystallinity with degradation, which was attributed to predominately degradation of free amorphous regions. Depending on the crystallinity, the elastic modulus increased at first, and decreased slightly. Both bulk and surface-tethered stimuli-responsive polymers were studied on amine functionalized magnetite (Fe3O4) nanoparticles. Stimuli-responsive polymers studied, including poly(N-isopropylacrylamide) (PNIPAM), poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA), and poly(itaconic acid) (PIA), were grafted via surface-initiated aqueous atom transfer radical polymerization (SI-ATRP). Both Fourier transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) spectroscopies showed the progression of the grafting. The change in particle size as a function of temperature was measured using dynamic light scattering (DLS). Once the PIA was grafted from the Fe3O4 nanoparticles for 13 h, the PIA thickness was around 13 nm. After the PNIPAM was grafted for 6 h, the stimuli-responsive nanocomposites with a lower critical solution temperature (LCST) of 32 °C exhibited a particle size of 236 nm. Moreover, a variety of stimuli-responsive bulk block copolymers were synthesized. The stimuli-responsive nanocomposites could be good candidates as drug carriers for the targeted and controllable drug delivery.

A biodegradable alternative to synthetic plastics was explored in this study through the extrusion of a soy-based protein/fiber composite film. Two fractions of fibers with different size distributions (nano- to micro-) were isolated from soy pods and stems using a chemi-mechanical method. Fibers through successive treatments were characterized via microscopy, x-ray diffraction, and Fourier Transform infrared analysis (FTIR). The continuous extrusion of homogenous SPI film (0.08 to 0.3 mm thick) was reported for the first time. Processing window was limited by protein sensitivity to moisture and heat. With the incorporation of extracted fibers, homogenous films were obtained with a concentration below 0.5% w/w fiber/SPI. Increasing fiber content resulted in the formation of aggregates. At the optimal concentration of 0.25% w/w fiber/SPI, films exhibited mild improvements in mechanical performance most noticeable at a high RH (84%). Film properties with and without fiber addition were negatively affected by relative humidity. Titanium dioxide addition suggested mild coupling effects for SPI and fiber. / Hannam Soy Foundation / Ontario Ministry of Agricultural, Food, and Rural Affairs (OMAFRA)