Verificação da autenticidade da identificação de espécies de pescados comercializados com diferentes formas de processos em supermercados e mercados de Maceió por meio da técnica de DNA barcoding

• Autor(a) principal: Pereira, Vanessa Lessa
• Data de Publicação: 2020
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal de Alagoas (UFAL)
• Texto Completo: http://www.repositorio.ufal.br/handle/riufal/7755
• topic: Código de barras de DNA taxômico; Peixes - Identificação; Pescados - Comércio - Fraude; DNA barcoding; Fish mislabeling; Seafood fraud; Northeast; Brazil; CNPQ::CIENCIAS BIOLOGICAS::GENETICA

The seafood has a huge importance as a nutritional source for millions of people around the world, corresponding, in 2015, to 17% of the animal protein ingested. Over half of the global production of fish is sold with some kind of processing. This fact can facilitate frauds in the identification of seafood species, through substitution of species that have a high commercial value by species that have lower commercial value, on the part of the fish productive chain components or by merchants. That happens because depending on the kind of process, there’s a possibility of removing morphological characters that can promote the physical identification of the seafood, making it difficult or impossible to identify it morphologically. As many other countries, in Brazil, the fraud in seafood is present too. This practice can cause several impacts in some areas, such as: economy, conservation and human health, in addition to directly affecting consumer rights. To identify frauds, exists a extremely efficient resource: the genetic identification of species, through DNA barcoding technique, which consists on sequencing a region of approximately 655 pb of mitochondrial cytochrome oxidase subunit I (COI) gene. The present study had as aims make the genetic identification of fish species sold with some kind of processing in commercial establishments of Maceió, city of Alagoas state, and carry out the verification of the authenticity of the species informed by the seller or on the packaging. 42 samples was obtained from 17 supermarkets and markets of 11 neighborhoods of Maceió/AL city. The analysis of the samples obtained involved: (1) organic extraction of DNA process with phenol-chloroform or through Chelex method; (2) DNA amplification (PCR); (3) purification with isopropanol and ethanol; (4) sequencing with the Kit BigDye Terminator; (5) genetic identification of specie by comparison of obtained sequence with sequences deposited in NCBI GenBank database and (6) characterization or not of frauds according to official Brazilian documents that are used for seafood inspections. 37 samples of the 42 obtained samples were successful in all methodological stages of the present work. Of the 37 successful samples, 25 samples demonstrated agreement between informed specie and identified specie, but 11 of the 37 samples didn’t show agreement between labelled specie and identified scientific name. Of the 11 samples characterized as fraud, 10 of them were labeled as “Bacalhau” and were identified as Gadus chalcogrammus (“Alaska pollock”) and Pollachius virens (“Saithe”). According to the obtained results, in general, the fish mislabeling percentage on seafood sales found on commercial establishments of Maceió/AL city, demonstrate similarity when compared to majority studies in Brazil. However, when the obtained fish mislabeling percentage are compared with the most part of the results obtained for other countries, the value obtained in the present study was bigger. Analyzing specifically the “Bacalhau”, its mislabeling percentage was very high, upper the value obtained on published studies carried in several countries, including Brazil.