2026-04-142026-04-142026-02-23SANTOS, João Vitor Sá dos. Autenticação de bagres do gênero Brachyplatystoma revela substituição fraudulenta no comércio de pescado no estado do Pará. Orientadora: Simoni Santos da Silva. 2026. 17 f. Trabalho de Curso (Licenciatura em Ciências Biológicas) – Faculdade de Ciências Biológicas. Instituto de Estudos Costeiros, Campus Universitário de Bragança, Universidade Federal do Pará, Bragança-PA, 2026. Disponível em: https://bdm.ufpa.br/handle/prefix/9454. Acesso em: .https://bdm.ufpa.br/handle/prefix/9454The authenticity of seafood products is a critical issue for the conservation of natural resources, consumer transparency, and food safety. Therefore, this study aimed to authenticate products labeled as dourada (Brachyplatystoma rousseauxii), filhote (Brachyplatystoma filamentosum), and piramutaba (Brachyplatystoma vaillantii) commercialized in supermarkets and restaurants in the state of Para, Brazil, as well as to assess the occurrence and potential motivations of species substitutions. A total of 122 frozen samples were collected from supermarket chains (62 labeled as dourada and 60 as piramutaba), and 84 ready-to-eat dishes were obtained from restaurants (45 marketed as dourada and 39 as filhote). Supermarket samples were identified at the species level using multiplex PCR targeting the mitochondrial Control Region. The results showed that 100% of the products labeled as piramutaba were authentic, as they exhibited banding patterns characteristic of B. vaillantii (451 bp and the 160 bp control band). In contrast, only 58.1% of the products labeled as dourada were authentic, displaying banding patterns characteristic of B. rousseauxii (580 bp and 160 bp), whereas 41.9% (N = 26/62) of the samples were substituted. Among the substituted samples, 23 were identified as piramutaba (451 bp and 160 bp), and three were identified by sequencing as Sciades proops. For restaurant samples, a multiplex PCR minibarcode protocol targeting the COI gene was applied. Substitution was detected in 100% (N = 39) of the dishes marketed as filhote. Among these, 17 samples were identified as dourada (88 bp and 160 bp), and three as piramutaba (254 bp and 160 bp). The remaining 19 samples sold as filhote showed only the 160 bp control band and were subsequently identified by sequencing as Brachyplatystoma platynemum (N = 18) and Brachyplatystoma juruense (N = 1). Among dishes sold as dourada, 55.6% (N = 25) were authentic, exhibiting the expected banding pattern of 88 bp and 160 bp, whereas 44.4% (N = 20/45) were substituted with piramutaba, as indicated by the presence of banding patterns of 254 bp and 160 bp. A common pattern observed in both supermarkets and restaurants was the replacement of higher-value target species with lower-value fish, indicating economically motivated commercial fraud. The results demonstrate that multiplex PCR protocols are efficient, rapid, and cost-effective tools for species authentication and can be applied in routine monitoring and certification programs. Furthermore, the findings highlight the urgent need for effective public policies to prevent fraud in the fish trade.Acesso AbertoPescadoBagres AmazônicosAutenticação molecularPCR multiplexFraude comercialFish productsAmazonian catfishesMolecular authenticationMultiplex PCRCNPQ::CIENCIAS BIOLOGICAS::GENETICATrabalho de Curso - Graduação - MonografiaAttribution-NonCommercial-NoDerivs 3.0 Brazil