http://repositorio.ufgd.edu.br/jspui/handle/prefix/854 2026-09-03T19:52:55Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/7013 Título: Desenvolvimento e caracterização de filme polimérico produzido a partir de gelatina de pele detilápia (Oreochromis niloticus) contendo lignina encapsulada Autor(es): Eberhart, Markus Rafael Carvalho Primeiro Orientador: Paz, Marcelo Fossa da Abstract: The development of biodegradable films from agro-industrial waste represents an alternative to conventional synthetic polymers. This study aimed to develop and characterize films based on gelatin obtained from Nile tilapia (Oreochromis niloticus) skin, containing lignin encapsulated by pectin (LP). The gelatin showed an extraction yield of approximately 16%. The films were produced via casting using formulation M4, composed of 5% gelatin, 1% glutaraldehyde, and 0.6% glycerin, as well as formulations M4 + LP 0.2% and M4 + LP 1.0%. Colorimetric and mechanical properties, solubility, biodegradation, and spectroscopic characteristics (UV-Vis diffuse reflectance, fluorescence, and FTIR) were evaluated. Quantitative data were analyzed using descriptive statistics, ANOVA, and Tukey's test, with a significance level of 5%. Tensile strength was 8.00 MPa for M4, 7.68 MPa for M4 + LP 0.2%, and 10.04 MPa for M4 + LP 1.0%, demonstrating an increase of approximately 25.5% in the formulation with the highest LP concentration. Conversely, elongation decreased from 87.04% to 40.88% and 16.75%, respectively, indicating increased rigidity and reduced matrix mobility. The average mass gain in the permeability test was 0.1579, 0.1549, and 0.1212 g·day⁻¹ for M4, M4 + LP 0.2%, and M4 + LP 1.0%, respectively. Water vapor permeability decreased from 4.0062 to 3.9301 and 3.0758 g·mm·m⁻²·day⁻¹·kPa⁻¹, corresponding to a reduction of approximately 23.2% for M4 + 1.0% LP. Average solubility showed a slight decrease, from 18.83 ± 1.78% to 18.27 ± 2.07% and 17.94 ± 0.83%, with no significant difference according to ANOVA (F = 0.374; p = 0.695). In the soil burial test, the films lost integrity before a complete mass curve could be obtained, with disintegration and the presence of mycelium observed by the sixth day. Regarding diffuse reflectance, the average value in the UV region dropped from 6.12% to 4.87% and 2.05%. The maximum Kubelka–Munk function increased from 9.02 to 11.22 and 28.42, representing a 214.9% increase for the formulation with 1.0% LP and indicating greater ultraviolet radiation attenuation. In fluorescence analysis, peak maxima remained between 495.5 and 497.0 nm, but intensity decreased from 3198 a.u. to 1859 and 1301 a.u., corresponding to quenching rates of 41.87% and 59.32%. The full width at half maximum (FWHM) ranged from 76.6 nm for the control to 84.1 nm for M4 + 1.0% LP. FTIR analysis confirmed characteristic bands for gelatin, lignin, and pectin without the formation of new detectable functional groups, suggesting predominantly intermolecular interactions. The pectin exhibited an estimated degree of methylation between 40% and 46%, classifying it as low-methoxyl pectin. It is concluded that M4 + 1.0% LP exhibited the best performance regarding barrier properties, mechanical strength, and optical protection, albeit with a marked loss of flexibility. Editor: Universidade Federal da Grande Dourados Tipo: Dissertação 2026-07-28T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6916 Título: Avaliação do crescimento de Limnospira platensis (Espirulina) com o uso de extratos vegetais de Camellia sinensis e Lemna minor Autor(es): Moura , Leticia Bueno de Primeiro Orientador: Paz , Marcelo Fossa da Abstract: With the aim of developing a nutritious and economical culture medium for the production of Limnospira platensis (spirulina), four culture media were prepared: one formulated solely with NPK fertilizer plus salts (medium X), two based on NPK fertilizer plus plant extracts of Lemna minor (Lentil medium) and Camellia sinensis (Green Tea medium), and one base medium (Zarrouk). After analysis, it was observed that all alternative media based on NPK fertilizer were able to sustain the growth of Limnospira platensis at biomass levels similar to or even higher than the standard Zarrouk medium, provided the cultivation period was sufficiently long. At the end of the experiment, it was observed that the Zarrouk medium presented the highest crude protein content, differing significantly from the other media; the media containing plant extracts did not differ from each other, while medium X presented the lowest value. After testing the toxicity of spirulina cultivated in different culture media, it was observed that there was lower survival in the control treatment compared to all treatments containing Limnospira platensis extract, presenting an average of 65.5 ± 18.0%, while the extracts from media X, CV, Z, and L showed average survival rates of 97.1 ± 4.35%, 97.7 ± 4.25%, 97.1 ± 4.35%, and 100.0 ± 0.0%, respectively. Finally, it is concluded that alternative media based on NPK and plant extracts are technically viable and economically advantageous for spirulina production, with a trade-off between growth rate and final productivity defining production strategies adapted to different industrial objectives. Editor: Universidade Federal da Grande Dourados Tipo: Dissertação 2026-03-27T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6875 Título: Avaliação ambiental da aquicultura em tanques-rede em um assentamento rural: aplicação de ferramentas de sustentabilidade integrada Autor(es): Cabanha, Fernando da Silva Primeiro Orientador: Albuquerque, Daniele Menezes Abstract: Aquaculture represents an important productive activity for food supply and economic development. However, its expansion requires careful attention to environmental impacts and sustainability. In this context, this study analyzed Brazilian scientific production on aquaculture from an environmental perspective, aiming to identify patterns and trends in how research has addressed environmental impacts, monitoring, and assessment of aquatic organism farming practices. A cienciometric analysis was conducted using the Scopus database, applying the search strategy (“aquaculture” OR “fish farm*” OR “pisciculture”) AND (“environmental impact” OR “environmental assessment” OR “environmental monitoring”). After applying filters and manual validation, 203 articles published between 1996 and 2024 were selected. Analyses performed with the support of Excel, VOSviewer, and Biblioshiny indicated a significant increase in scientific output from 2010 onwards, highlighting the role of public institutions and international collaborations. The main research themes included water quality, heavy metals, sustainability, life cycle assessment, and microplastics. The results indicate that Brazilian research on aquaculture and the environment has consolidated as a multidimensional and interdisciplinary field, although gaps remain, particularly regarding small-scale aquaculture, continental systems, and socio-environmental approaches. Editor: Universidade Federal da Grande Dourados Tipo: Dissertação 2026-04-13T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6874 Título: Avaliação da viabilidade produtiva de meio alternativo à base de Lemna minor para o cultivo de Chlorella sp Autor(es): Andrade , Bruna Aparecida Mortari de Primeiro Orientador: Paz, Marcelo Fossa da Abstract: Currently, microalgae represent one of the most promising sources for generating bio-inputs, but the greatest difficulty faced is the high cost of culture media. Therefore, given the scarcity of studies on new formulations, the present work aims to evaluate the behavior of the microalga of the genus Chlorella in a medium enriched with the extract of the macrophyte Lemna minor, which is easily found in large quantities in the natural environment, to quantify the amount of protein generated by the microalga in an alternative medium, and to verify the effectiveness of cryopreservation of the species through the maintenance of its viability. The water sample was obtained from the Itá stream, in the Barra do Itá settlement, in Bela Vista – MS. Isolation was performed using the “streak plating” method, in which a sample of the obtained water was subjected to streaking using a platinum loop on a Petri dish containing a solid medium composed of agar (1%) and NPK agricultural fertilizer (10-10-10 1.0 g.L-1). After plating, the plates were kept on a bench under a 16-hour photoperiod until the first isolated colonies grew. To prepare the extract, 2.5% w/v of dried and crushed L. minor was added to distilled water, which was kept boiling for 15 minutes. Tests showed that the medium enriched with 1% and 2% Lemna minor was more nutritious for Chlorella sp. compared to the adapted BBM medium. Macronutrient analyses of the 2.5% Lemna minor extract show that this macrophyte has a high nutritional content, largely due to its ability to absorb large quantities of nutrients present in the culture medium. However, further academic research is needed on the use of this macrophyte as a nutrient source for other microorganisms and on other potential nutrient suppliers for new alternative media formulations. The study also demonstrated that the cryopreservation of Chlorella sp. At -80°C using 10% glycerol as a cryoprotectant, it is viable for short to medium term storage (up to 42 days), maintaining cell viability and recovery capacity after thawing. Editor: Universidade Federal da Grande Dourados Tipo: Dissertação 2026-02-26T00:00:00Z