TEDE Collection:

Estrutura populacional, reprodução e dieta de Gymnogeophagus taroba (Casciotta, Almirón, Piálek & Říčan, 2017), espécie endêmica de uma ecorregião Neotropical

2026-10-27T16:43:56Z

Title: Estrutura populacional, reprodução e dieta de Gymnogeophagus taroba (Casciotta, Almirón, Piálek & Říčan, 2017), espécie endêmica de uma ecorregião Neotropical Autor: Faria, Ana Elisa Campos Primeiro orientador: Makrakis, Maristela Cavicchioli Abstract: The Iguaçu River basin is considered a freshwater ecoregion due to the high degree of endemism of its ichthyofauna. Gymnogeophagus taroba is an endemic, small species and studies on its bioecology are scarce. Thus, the aim of the study was to characterize the population structure and feeding habits of G. taroba. Collections were carried out monthly from January 2010 to January 2011 and from September 2012 to December 2016, in the Lower Iguaçu River region, covering areas within the Iguaçu National Park (INP) and anthropized areas outside the INP. In all, 802 specimens were analyzed, with total length and weight ranging from 1.5 to 15 cm and from 0.02 to 51.90 g, respectively. The sex ratio did not show significant differences for the population and the largest length classes contained only male individuals. The weight-length relationship for both sexes exhibited isometric growth. The reproductive period established through the average variation of the Gonadal-Somatic Index (GSI) and frequency distribution of males and females encompassed between August and February, with reproductive peaks in September and November for females and in October for males. The size of the first gonadal maturation (L50) corresponded to 6.03 cm for males and 4.15 cm for females. The analysis of the frequency of degrees of repletion by periods (morning, afternoon and night), reveled greater feeding activity during the night. The feeding habit of the species, determined through the Index of Feeding Importance (IFI), was characterized as a benthic insectivore, with emphasis on the consumption of larvae of Chironomidae and Trichoptera. The study provides unprecedented information about certain parameters of the population structure, reproduction and feeding habits of G. taroba, which will assist in effective conservation actions for the species. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação

Prospecção de bactérias produtoras de biossurfactantes em áreas de transição (portos)

2026-10-01T18:41:06Z

Title: Prospecção de bactérias produtoras de biossurfactantes em áreas de transição (portos) Autor: Batista, Paula Frassinetti da Silva Primeiro orientador: Makrakis, Sergio Abstract: Biosurfactants, amphiphilic compounds produced by microorganisms, have attracted increasing interest due to their biodegradability, low toxicity, and effectiveness under diverse environmental conditions, making them promising alternatives to synthetic surfactants in remediation processes and industrial applications. This dissertation is structured into two complementary chapters. The first chapter presents a systematic review on the prospecting of biosurfactants in transitional ecosystems, such as mangroves, port areas, and coastal zones, with emphasis on their applications in bioremediation. Sixteen articles published between 2015 and 2025 were analyzed, selected from international databases (Scopus, Web of Science, and PubMed). The studies indicate a predominance of biosurfactants belonging to the glycolipid and lipopeptide classes, produced mainly by bacteria of the genera Pseudomonas, Bacillus, and Rhodococcus, as well as yeasts such as Candida and Starmerella. A growing trend toward the use of agro-industrial residues as substrates was also observed, reinforcing the alignment of these technologies with sustainability principles and the circular economy. The reported applications demonstrate high efficiency of biosurfactants in the solubilization and mobilization of pollutants, including hydrocarbons and heavy metals, highlighting their strategic role in the bioremediation of impacted transitional environments. In the second chapter, an experimental study was conducted to prospect biosurfactant-producing bacteria in port areas of the municipality of Piúma, Espírito Santo, Brazil, characterized by contamination from diesel oil. Sediment samples were collected from points of high vessel traffic, resulting in the isolation of seven bacterial strains. These isolates were cultivated in minimal salt medium (MSM), using diesel oil as the sole carbon source. The surfactant activity of the produced metabolites was evaluated using drop-collapse and oil-spreading tests, as well as the emulsification index (E24), employing diesel oil and gasoline as oily phases. The biosurfactants exhibited low emulsifying activity against diesel oil (E24 < 10%); however, they demonstrated moderate efficiency in the emulsification of gasoline, with indices reaching approximately 35% for some isolates, indicating greater affinity for light hydrocarbons. Taken together, the findings from the systematic review and the experimental study reinforce the potential of biosurfactants as valuable tools for the remediation of contaminated environments and highlight the importance of transitional ecosystems— such as mangroves and port areas—as reservoirs of microorganisms with biotechnological relevance. The integration of these approaches contributes to advancing knowledge on the microbial diversity involved in biosurfactant production, their applications, and the remaining challenges related to large-scale production and the economic feasibility of these bioproducts in environmental and industrial contexts. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação

Revisão sistemática a respeito de off-flavors causados por Geosmina e 2-Metilisoborneol (MIB) em produtos aquáticos

2026-10-01T18:23:02Z

Title: Revisão sistemática a respeito de off-flavors causados por Geosmina e 2-Metilisoborneol (MIB) em produtos aquáticos Autor: Santos, Osvaldo Gois Primeiro orientador: Ballester, Eduardo Luis Cupertino Abstract: This systematic review addresses the issue of sensory quality of freshwater fish farmed by aquaculture. Off-flavors are undesirable flavors and odors in farmed fish that affect the quality and acceptance of the product by the consumer, causing serious financial losses to the production chain. The PRISMA method was used to select articles related to the study theme, where 7,576 documents were analyzed, opting for recent articles, published in the last six years, obtained from the Scopus and Web of Science databases. After applying the exclusion terms (off-flavor, aquaculture, fish, articles, periods, GSM and MIB), forty-four relevant studies were obtained, in which we sought to identify the objectives of the study, the species studied, the farming system, results achieved, gaps and future studies of each investigated article, briefly reporting their objectives and results. Most studies emphasize the influence of water quality, climate issues, management, feed quality, especially the presence of cyanobacteria, algal blooms, fungi, and metabolic compounds such as GSM, MIB, among others, which contribute to the formation of unpleasant flavors and odors. The results highlight the need to improve management practices and control of altered flavors and odors in aquaculture, in addition to suggesting the need for further research to develop more effective and accessible methods. The importance of continuous monitoring of water quality is emphasized to prevent the formation of undesirable flavors. In summary, the review provides a comprehensive overview of undesirable flavors and odors in freshwater fish, identifying gaps in knowledge and proposing directions for future research, essential for the sustainability and quality of aquatic production. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação

Atratividade e palatabilidade da proteína hidrolisada de penas de aves com diferentes níveis de sulfito em rações para alevinos de tilápia do Nilo (Oreochromis niloticus)

2026-10-01T17:26:04Z

Title: Atratividade e palatabilidade da proteína hidrolisada de penas de aves com diferentes níveis de sulfito em rações para alevinos de tilápia do Nilo (Oreochromis niloticus) Autor: Marinho, Ana Rizia Nascimento Primeiro orientador: Signor, Altevir Abstract: The present study aimed to evaluate the attractiveness and palatability of six diets containing different levels of hydrolyzed feather protein, with and without sulfite addition, for Nile tilapia (Oreochromis niloticus) juveniles. The formulations tested were: SFPE (negative control, with 2% feather meal), FPE (positive control, with 2% fish meal), PHP1%S (1% hydrolyzed feather protein without sulfite), PHP2%S (2% hydrolyzed feather protein without sulfite), PHP1%C (1% hydrolyzed feather protein with sulfite), and PHP2%C (2% hydrolyzed feather protein with sulfite). Twelve juveniles (7.38 ± 0.20 g) were distributed in 20-liter aquaria and fed six times per day with 0.1889 g per feeding (35 pellets), following a completely randomized experimental design. Feeding behavior was recorded via video for three minutes during each feeding session, analyzing the following parameters: time to first pellet capture, number of rejections after capture, intake (number of pellets consumed), and time spent feeding. A significant difference was observed at 8:00 h for the attractiveness and palatability index (API) and pellet rejections after capture, while no significant differences were found for the other time points and parameters (p > 0.05). Therefore, it can be concluded that the tested diets exhibit attractiveness and palatability comparable to the control diets and may be considered for inclusion in diets for Nile tilapia. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Dissertação